Earth working machine having a rotatable working apparatus axially positionally retainable with high tightening torque by means of a central bolt arrangement, and method for establishing and releasing such retention

Abstract

A bearing component for mounting a replaceable milling drum on an earth working machine includes an annular connecting flange having a central axis. A bearing stem protrudes from the connecting flange axially in a first direction to a first axial end, the bearing stem having an outer surface including at least first and second cylindrical bearing surfaces axially spaced from each other. The bearing stem further includes a centering recess open at a second axial end opposite the first axial end, the centering recess including an opening angle decreasing in steps so that the centering recess tapers in the first direction, the centering recess forming a portion of the central opening.

Claims

1. A bearing component for mounting a replaceable milling drum on an earth working machine, comprising: an annular connecting flange having a central axis; a bearing stem protruding from the connecting flange axially in a first direction to a first axial end, the bearing stem having an outer surface including at least first and second cylindrical bearing surfaces axially spaced from each other, a furthest one of the cylindrical bearing surfaces from the connecting flange having a smaller diameter than a next furthest one of the cylindrical bearing surfaces from the connecting flange, the bearing stem having a central opening therethrough co-axial with the central axis; and the bearing stem further including a centering recess open at a second axial end opposite the first axial end, the centering recess including an opening angle decreasing in steps so that the centering recess tapers in the first direction, the centering recess forming a portion of the central opening.

2. The bearing component of claim 1, further comprising: a radial step formed on a side of the connecting flange facing away from the first direction.

3. The bearing component of claim 1, wherein: the connecting flange includes three equally spaced arc shaped recesses formed in a periphery of the connecting flange.

4. The bearing component of claim 3, wherein: the connecting flange includes a plurality of fastener openings located on a radius from the central axis which radius overlaps the arc shaped recesses, the plurality of fastener openings including three groups of fastener openings, each group being located in a circumferential direction between two adjacent ones of the arc shaped recesses, the fastener openings of each group being arranged equidistantly from one another in the circumferential direction.

5. The bearing component of claim 1, wherein: an axially tapering conformation of the outer surface of the bearing stem is such that an opening angle (α, β) of first and second notional enveloping cones (K1, K2), which respectively abut tangentially against two osculating circles (S1, S2, S3, S4) located with an axial spacing from one another on the outer surface of the bearing stem and surround an axial portion, located between the osculating circles (S1, S2, S3, S4), of the bearing stem, is smaller for the second notional enveloping cone (K2) of osculating circle pair (S3, S4) located closer to the connecting flange.

6. The bearing component of claim 5, wherein: the first axial end of the bearing stem is an axial longitudinal free end of the bearing stem located remotely from the connecting flange; and the opening angle (α) of the first notional enveloping cone (K1), whose first osculating circle (S1), located farther from the connecting flange, is located at the first axial end of the bearing stem, and whose second osculating circle (S2), located closer to the connecting flange is located axially between the first osculating circle (S1) and an axial longitudinal end of the first cylindrical bearing surface which is located closer to the first axial end of the bearing stem, is at least 1.5 times as large as the opening angle (β) of the second notional enveloping cone (K2) whose first osculating circle (S3), located farther from the connecting flange is located at the axial longitudinal end of the first cylindrical bearing surface which is located closer to the first axial end of the bearing stem.

7. The bearing component of claim 6 wherein: the opening angle (a) of the first notional enveloping cone (K1) is at least 2.5 times as large as the opening angle (β) of the second notional enveloping cone (K2).

8. The bearing component of claim 6, wherein: the opening angle (β) of the second notional enveloping cone (K2) is in a range of from about 5° to about 15°.

9. The bearing component of claim 6, wherein: the opening angle (β) of the second notional enveloping cone (K2) is in a range of from about 8° to about 13°.

10. The bearing component of claim 1, wherein: the centering recess comprises a main centering recess portion located closer to the second axial end and a pre-centering recess portion located farther from the second axial end, such that a first virtual cone (K3) that abuts respectively against the edges (R1, R2), located axially closest to the second axial end, of the main centering recess portion and of the pre-centering recess portion has a larger opening angle (γ) than a second virtual cone (K4) that abuts on the one hand against the edge (R2), located axially closest to the second axial end of the pre-centering recess portion and against an edge (R3), located closest to the second axial end, of a recess that axially follows the pre-centering recess portion in the first direction away from the second axial end and of which the centering recess is a part.

11. The bearing component of claim 10, wherein: the opening angle (γ) of the first virtual cone (K3) is in a range of from about 3 to about 6 times larger than an opening angle (δ) of the second virtual cone (K4).

12. The bearing component of claim 11, wherein: the opening angle (γ) of the first virtual cone (K3) is in a range of from about 20° to about 40°.

13. The bearing component of claim 11, wherein: the opening angle (γ) of the first virtual cone (K3) is in a range of from about 25° to about 35°.

14. The bearing component of claim 10, wherein: the opening angle (γ) of the first virtual cone (K3) is in a range of from about 4 to about 5 times larger than an opening angle (δ) of the second virtual cone (K4).

15. The bearing component of claim 10, wherein: an axially tapering conformation of the outer surface of the bearing stem is such that an opening angle (α, β) of first and second notional enveloping cones (K1, K2), which respectively abut tangentially against two osculating circles (S1, S2, S3, S4) located with an axial spacing from one another on the outer surface of the bearing stem and surround an axial portion, located between the osculating circles (S1, S2, S3, S4), of the bearing stem, is smaller for the second notional enveloping cone (K2) of the osculating circle pair (S3, S4) located closer to the connecting flange; and the opening angle (γ) of the first virtual cone (K3) is larger than the opening angle (α) of the first notional enveloping cone (K1).

16. The bearing component of claim 15, wherein: the opening angle (δ) of the second virtual cone (K4) is smaller than the opening angle (β) of the second notional enveloping cone (K2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be explained in further detail below with reference to the appended drawings, in which:

(2) FIG. 1 is a schematic side view of an embodiment according to the present invention of an earth working machine in the form of a large milling machine, in a position for rolling travel operation;

(3) FIG. 2 is a schematic longitudinal section view through the working apparatus of the earth working machine of FIG. 1 in an operational state for earth working, in which the section plane contains the rotation axis of the working apparatus;

(4) FIG. 3 is an enlarged partial longitudinal section view of the right (in FIG. 2) longitudinal end of the drive configuration and working apparatus;

(5) FIG. 4 is a perspective view of a bolting moment bracing arrangement for establishing and/or releasing axial positional retention of the milling drum on a drive configuration of the earth working machine;

(6) FIG. 5 shows, in isolation, the bolting moment bracing arrangement of FIG. 4 embodied as a tool arrangement;

(7) FIG. 6 is a partial longitudinal section view, corresponding in terms of essential constituents to FIG. 3, of the right longitudinal end region of the drive configuration and milling drum, having a bolting moment bracing arrangement according to FIGS. 4 and 5 arranged on the bolt arrangement;

(8) FIG. 7 is a longitudinal section view, corresponding to the view of FIG. 6, of an alternative embodiment of the drive configuration and milling drum;

(9) FIG. 8 shows a drive configuration and milling drum, corresponding substantially to the embodiments of FIGS. 3 and 6, having a release component for pulling the milling drum axially off the drive configuration;

(10) FIG. 9 shows the release component of FIG. 8 in isolation;

(11) FIG. 10 shows a third embodiment of the drive configuration and milling drum in a partial longitudinal section view corresponding to FIGS. 3 and 6 to 8;

(12) FIG. 11A is a side view of a preferred bearing component encompassing a connecting flange and a bearing stem, protruding therefrom, as shown in FIG. 6;

(13) FIG. 11B is a longitudinal section view of the bearing component of FIG. 11A;

(14) FIG. 12 is a plan view of the bearing component of FIGS. 11A and 11B;

(15) FIG. 13A is a side view of a bearing component alternative to the one of FIG. 11A;

(16) FIG. 13B is a longitudinal section view of the bearing component of FIG. 13A; and

(17) FIG. 14 is a plan view of the bearing component of FIGS. 13A and 13B.

DETAILED DESCRIPTION

(18) In FIG. 1, an embodiment according to the present invention of an earth working machine in the form of a ground milling or road milling machine is labeled 10 in general. It encompasses a machine frame 12 that constitutes the basic framework for a machine body 13. Machine body 13 encompasses machine frame 12 and the components of machine 10 which are connected to the machine frame and are optionally movable relative thereto.

(19) Machine body 13 encompasses front lifting columns 14 and rear lifting columns 16, which are connected at one end to machine frame 12 and at the other end respectively to front drive units 18 and to rear drive units 20. The distance of machine frame 12 from drive units 18 and 20 is modifiable by way of lifting columns 14 and 16.

(20) Drive units 18 and 20 are depicted by way of example as crawler track units. In a departure therefrom, individual, or all, drive units 18 and/or 20 can also be wheel drive units.

(21) The viewer of FIG. 1 is looking toward the earth working machine (or simply “machine”) 10 in transverse machine direction Q that is orthogonal to the drawing plane of FIG. 1. A longitudinal machine direction orthogonal to transverse machine direction Q is labeled L and extends parallel to the drawing plane of FIG. 1. A vertical machine direction H likewise extends parallel to the drawing plane of FIG. 1 and orthogonally to longitudinal and transverse machine directions L and Q. The arrowhead of longitudinal machine direction L in FIG. 1 points in a forward direction. Vertical machine direction H extends parallel to the yaw axis of machine 10, longitudinal machine direction L extends parallel to the roll axis, and transverse machine direction Q extends parallel to pitch axis Ni.

(22) Earth working machine 10 can comprise an operator's platform 24 from which a machine operator can control machine 10 via a control panel 26.

(23) Arranged below machine frame 12 is a working assembly 28, here constituting, for example, a milling assembly 28 having a milling drum 32, received in a milling drum housing 30, that is rotatable around a milling axis R extending in transverse machine direction Q so that substrate material can be removed therewith during an earth working operation, starting from contact surface AO of substrate U to a milling depth determined by the relative vertical position of machine frame 12. Milling drum 32 is therefore a working apparatus within the meaning of the present Application.

(24) The vertical adjustability of machine frame 12 by way of lifting columns 14 and 16 also serves to set the milling depth, or generally working depth, of machine 10 in the context of earth working. Earth working machine 10 depicted by way of example is a large milling machine, for which the placement of milling assembly 28 between the front and rear drive units 18 and 20 in longitudinal machine direction L is typical. Large milling machines of this kind, or indeed earth-removing machines in general, usually comprise a transport belt so that removed earth material can be transported away from machine 10. In the interest of better clarity, a transport belt that is also present in principle in the case of machine 10 is not depicted in FIG. 1.

(25) It is not apparent from the side view of FIG. 1 that machine 10 comprises, in both its front end region and its rear end region, two respective lifting columns 14 and 16 each having a drive unit 18, 20 connected to it. Front lifting columns 14 are respectively connected to drive units 18, in a manner also known per se, by means of a drive unit connecting structure 34, for example a connecting fork fitting around drive unit 18 in transverse machine direction Q. Rear lifting columns 16 are connected to their respective drive unit 20 via a drive unit connecting structure 36 constructed identically to drive unit connecting structure 34. Drive units 18 and 20 are of substantially identical construction, and constitute propelling unit 22 of the machine. Drive units 18 and 20 are motor-driven, as a rule by a hydraulic motor (not depicted).

(26) The drive energy source of machine 10 is constituted by an internal combustion engine 39 received on machine frame 12. In the exemplifying embodiment depicted, milling drum 32 is rotationally driven by it. The output of internal combustion engine 39 furthermore makes available on machine 10 a hydraulic pressure reservoir by means of which hydraulic motors and hydraulic actuators on the machine can be operated. Internal combustion engine 39 is thus also a source of the propulsive power of machine 10.

(27) In the example depicted, drive unit 18, having a travel direction indicated by double arrow D, comprises a radially internal receiving and guidance structure 38 on which a circulating drive track 40 is arranged and is guided for circulating movement.

(28) Lifting column 14, and with it drive unit 18, is rotatable around a steering axis S by means of a steering apparatus (not further depicted). Preferably additionally, but also alternatively, lifting column 16, and with it drive unit 20, can be rotatable by means of a steering apparatus around a steering axis parallel to steering axis S.

(29) FIG. 2 is a longitudinal section view of milling drum 32 of FIG. 1 in a section plane containing rotation axis R of the milling drum.

(30) Milling drum 32 encompasses a substantially cylindrical milling drum tube 42 on whose radially outer side bit holders or quick-change bit holders, having milling bits in turn received replaceably therein, are provided in a manner known per se. A dot-dash line 44 indicates the effective diameter (cutting cylinder) of milling drum 32, defined by the milling bit tips of the milling bits (not depicted). Milling drum 32 is in an operational condition ready for earth-removing work. Milling drum 32 is connected for that purpose in torque-transferring fashion to a drive configuration 46. Milling drum 32 radially externally surrounds drive configuration 46.

(31) A planetary gearset that steps speed down and steps torque up is received in a transmission housing 52. A right (in FIG. 2) part 52a of transmission housing 52 is coupled to the ring gear of the planetary gearset for rotation together. A left (in FIG. 2) part 52b of transmission housing 52 is a machine frame-mounted part of machine body 13.

(32) Drive configuration 46 encompasses an internal tube 48, a support cone 50, and part 52a, rotatable relative to machine frame 12, of transmission housing 52. Support cone 50 and internal tube 48 are connected to one another, and are connected as an assembly to transmission housing part 52a for rotation together around drive axis A of drive configuration 46. With milling drum 32 in the operational state, drive axis A of drive configuration 46 and rotation axis R of milling drum 32 are coaxial.

(33) Milling drum tube 42 is braced against support cone 50 of drive configuration 46 by a negatively conical counterpart support cone 51.

(34) Drive configuration 46 is furthermore connected to a drive torque-transferring arrangement 54 that, in the example depicted, encompasses inter alia a belt pulley 55. Belt pulley 55 is connected to an input shaft (not depicted in FIG. 2) of the planetary gearset in transmission housing 52. The input shaft, connected to belt pulley 55 for rotation together, extends through a shaft tunnel 56 that is machine frame-mounted in the exemplifying embodiment depicted and is rigidly connected to transmission housing part 52b.

(35) Drive configuration 46 forms, with the machine frame-mounted assembly made up of transmission housing part 52b and shaft tunnel 56, a drive assembly 47 that projects axially into milling drum 32 from a drive axial end 32a of milling drum 32. Milling drum 32 preferably protrudes axially on both sides beyond drive configuration 46, constituting that part of drive assembly 47 which is rotatable relative to machine frame 12.

(36) Drive assembly 47, and with it drive configuration 46, is mounted on machine body 13 in the region of shaft tunnel 56. The mounting of drive configuration 46 in the region of the rotatable transmission housing part 52a constitutes a locating bearing of drive configuration 46. Axial longitudinal end 46a, located closer to belt pulley 55, of drive configuration 46 is therefore also referred to as the “locating bearing-side” longitudinal end 46a.

(37) Milling drum 32 extends axially, along its rotation axis (milling axis) R that coincides with drive axis A in the operational state, between drive axial end 32a located closer to drive torque-transferring arrangement 54 in FIG. 2 and a retention axial end 32b, located oppositely from the drive axial end, that is located closer to the axial positional retention point of milling drum 32 in the operational state.

(38) At non-locating bearing-side longitudinal end 46b located axially oppositely from locating bearing-side longitudinal end 46a, drive configuration 46 comprises a support ring 58 and an end-located cover 60 connected to support ring 58. In the exemplifying embodiment depicted, support ring 58 is connected to internal tube 48 by welding. Cover 60 can likewise be welded, or also bolted, onto support ring 58. It is connected to support ring 58 and to internal tube 48 for rotation together around drive axis A.

(39) Support ring 58 can be embodied in a variety of ways. Its conformation is not of essential importance. In the depictions of the present Application it is shown in a slightly differing form in each case, but this has no influence at all on the present invention.

(40) The same is true of the radially external regions of cover 60 which interact with support ring 58 to constitute a nonrotatable connection.

(41) In the first exemplifying embodiment depicted in FIG. 2, a hydraulic cylinder 62, which is arranged with its hydraulic cylinder axis coaxial with drive axis A of drive configuration 46, is received in interior 49 of drive configuration 46. Hydraulic cylinder 62 can be supplied with hydraulic fluid by means of a hydraulic connector line 64 through an energy passthrough opening 66 in cover 60.

(42) Hydraulic connector line 64 ends, at its longitudinal end located remotely from hydraulic cylinder 62, in a coupling configuration 68 that is connectable, in order to supply hydraulic cylinder 62, to a counterpart coupling configuration of a supply line (not depicted) so that piston rod 63 can be extended from hydraulic cylinder 62 and retracted back into it. Two hydraulic connector lines 64 can be provided in order to operate a preferred double-acting hydraulic cylinder, one for each movement direction of piston rod 63.

(43) Once axial positional retention, as shown in FIG. 2, of milling drum 32 on drive configuration 46 has been released, milling drum 32 can be axially pushed away from drive configuration 46 for deinstallation using piston rod 63, or pulled onto drive configuration 46 for installation.

(44) A connecting ring 70 is arranged radially internally on milling drum tube 42 in a region located closer to retention axial end 32b, and is connected, by way of a welded join in the example depicted, to milling drum tube 42 for rotation together.

(45) Milling drum tube 42 is rigidly connected to a connecting flange 74 via a connecting ring 70 by means of threaded studs 72.

(46) Provided on connecting flange 74, preferably in one piece therewith, is a bearing stem 74a that protrudes axially in a first direction toward retention axial end 32b from a connecting region of connecting flange 74 with connecting tube 70.

(47) With milling drum 32 in the operational state, a non-locating bearing 76 that braces drive configuration 46 is arranged on bearing stem 74a. Non-locating bearing 76, arranged at an axial distance from the locating bearing, can be pulled off axially from bearing stem 74a.

(48) Non-locating bearing 76 can be received, for example, in a side plate or side door 30a (see FIGS. 3, 4, 6, 7, and 10) that is part of milling drum housing 30 and is end-located axially oppositely from milling drum 32 at retention axial end 32b. All that is shown in FIG. 2 is a component 30b, rigidly connected to such a side wall 30a, constituting a bearing surface for the outer bearing ring of non-locating bearing 76.

(49) Side wall 30a, constituting side door 30a, is preferably provided pivotably on machine frame 12 so that drive configuration 46 and/or milling drum 32 in the interior of milling drum housing 28 can be made accessible by simply pivoting open and closed. Side door 30a is preferably pivotable around a pivot axis parallel to vertical machine direction H, since the pivoting of side door 30a then does not need to occur against gravity in any pivoting direction. Non-locating bearing 76, constituting non-locating assembly 85, is preferably mounted on side door 30a together with auxiliary component 86 (explained below) in such a way that the non-locating bearing, in particular constituting non-locating bearing assembly 85, is pivotable together with side door 30a. Opening side door 30a causes non-locating bearing 76, in particular non-locating bearing assembly 85, to be pulled axially off the bearing stem mounted by non-locating bearing 76. As is preferred, this can be bearing stem 74a that is connected to connecting flange 74. It can also be bearing stem (centering stem) 160a, described below in conjunction with the second exemplifying embodiment shown in FIG. 7, which protrudes axially from cover 160 of drive configuration 146 and passes through connecting flange 174.

(50) Also preferably, the distance of the side door pivot axis from side door 30a is greater than the radius of the cutting cylinder, shown in FIG. 2, of milling drum 32, so that the circular path of non-locating bearing 76 or of non-locating bearing assembly 85 when pivoting together with side door 30a has the largest possible radius and thus the least possible curvature. This makes it easier to pull non-locating bearing 76, in particular non-locating bearing assembly 85, off the bearing stem that mounts milling drum 32 for rotation around its rotation axis R, or to pull it onto said bearing stem.

(51) As will be explained in more detail with reference to the enlarged depiction in FIG. 3 of functional longitudinal end 46b of the drive configuration, milling drum 32 is retained in its axial position on drive configuration 46 only by a single central retaining bolt 78. Retaining bolt 78 constitutes a bolt arrangement of the present Application.

(52) Milling drum 32 is thus braced on drive configuration 46, coaxially with drive axis A, against counterpart support cone 51 and against connecting flange 74.

(53) In FIG. 3, support ring 58, cover 60, and connecting flange 74 have conformations that deviate slightly from what is depicted in FIG. 2. The conformations of the aforesaid components do not, however, differ sufficiently from what is depicted in FIG. 2 for those differences to have an influence on the implementation of the present invention.

(54) Hydraulic cylinder 62, with its piston rod 63, is omitted from FIG. 3 in the interest of clarity. Threaded studs 72 for connecting connecting flange 74 to connecting ring 70 are also not depicted in the interest of clarity.

(55) Embodied on cover 60, preferably in one piece therewith, is a centering configuration 60a in the form of a centering stem which protrudes from cover 60, in a direction away from the locating bearing-side longitudinal end of drive configuration 46, toward retention axial end 32b of milling drum 32. Centering stem 60a projects into a counterpart centering configuration 74b, embodied as a centering recess, on connecting flange 74, and thereby centers milling drum tube 42, connected rigidly to connecting flange 74, with respect to drive axis A. Connecting flange 74 is therefore a centering component recited in the introductory part of the description. The connecting flange 74 can be described as an annular connecting flange 74 having a central axis coincident with the drive axis A. Cover 60 comprises a central recess 60b, passing axially through it, through which piston rod 63 in FIG. 2 and FIG. 3 can pass axially.

(56) At the end region facing toward retention axial end 32b of centering stem 60a, recess 60b in centering stem 60a is equipped with an internal thread into which the central retaining bolt 78 is threaded.

(57) Although the bolt arrangement can also be embodied in several parts, for example by way of a threaded rod and a retaining nut optionally with a washer, rather than as a one-piece retaining bolt 78, the one-piece bolt arrangement in the form shown in FIG. 3 is preferred because of its simple and reliable handling and stowing capability. The central retaining bolt 78 encompasses a threaded shank 78a having an external thread, and a bolt head 78b projecting radially beyond threaded shank 78a and having a tool engagement configuration 78c known per se, for example in the form of a hex head polyhedron. Embodied between threaded shank 78a and tool engagement configuration 78c is an abutment portion 78d constituting an axially narrow but radially protruding cylinder. This abutment portion 78d is embodied in the present example in one piece with threaded shank 78a and tool engagement configuration 78c, but alternatively can also be provided as a separate washer.

(58) Bolt head 78b thus clamps bearing stem 74a, and with it connecting flange 74 and with that in turn connecting ring 70 and milling drum tube 42, axially against support cone 50 of drive configuration 46.

(59) When milling drum 32 is arranged axially at a distance from its operating position but still with a certain prepositioning, for example such that that longitudinal end of centering stem 60a which is located remotely from support ring 58 is already projecting into centering recess 74b of connecting flange 74, it is thus possible to move milling drum 32 with centering bolt 78 axially into its operating position. Care must simply be taken that pins 80 provided on cover 60 at a radial distance from drive axis A can travel into recesses 74c, provided for that purpose, of connecting flange 74, so as thereby to couple cover 60 to connecting flange 74 in order to transfer torque between drive configuration 46 and milling drum 32.

(60) Axially “pulling” or clamping milling drum 32 onto drive configuration 46 by means of retaining bolt 78 requires only a comparatively low level of torque that can be introduced via tool engagement configuration 78c into retaining bolt 78 using conventional torque wrenches or also mechanized torque wrenches.

(61) As an alternative to pulling or clamping milling drum 32 onto drive configuration 46 by means of retaining bolt 78, milling drum 32 can also be slid through the pivotable side door 30a onto drive configuration 46. During this sliding-on operation, not only is counterpart centering configuration 74b slid onto centering stem 60a, but non-locating bearing 76, in particular non-locating bearing assembly 85, is preferably also slid onto bearing stem 74a.

(62) In order to facilitate the conveying, mentioned in the preceding paragraph, of milling drum 32 into an operational position simply by pivoting side door 30a into its closed position shown in FIGS. 3, 6, 7, and 10 in which it closes off milling drum housing 30, earth working machine 10 preferably comprises an actuator that assists the pivoting of side door 30a at least in a movement direction, and at least in a movement region containing the closed position. Particularly preferably, this is a final movement region in the context of the movement of side door 30a into the closed position. The force needed in order to slide milling drum 32 onto drive configuration 46, and also the force needed to slide non-locating bearing 76 or non-locating bearing assembly 85 onto bearing stem 74a, can thus be applied entirely or at least partly by the actuator. Such an actuator can comprise, for example, one or several piston/cylinder arrangements. The cylinder is preferably pivot-mounted on machine frame 12. When side door 30a has been brought sufficiently close to an engagement configuration of the piston rod and when the piston rod is extended, side door 30a can be brought into engagement with the engagement configuration of the piston rod, preferably into a positive engagement transferring a particularly large amount of force, so that the one or several piston/cylinder arrangements can then at least assist, preferably independently execute, the remainder of the closing movement of side door 30a.

(63) Preferably the actuator can also assist or in fact execute the pivoting movement of side door 30a, together with non-locating bearing 76 or with non-locating bearing assembly 85, in an initial movement region of the pivoting movement of side door 30a out of the closed position toward the access position, non-locating bearing 76, in particular non-locating bearing assembly 85, being pulled off bearing stem 74a over that region. The actuator can also be an electromechanical actuator.

(64) A retaining moment for axial positional retention of milling drum 32 on drive configuration 46 by way of retaining bolt 78 is, however, orders of magnitude greater. This is introduced into retaining bolt 78, in accordance with the present invention, as depicted in FIG. 4.

(65) FIGS. 4 and 5 depict a bolting moment bracing arrangement 82 used to establish and release axial positional retention of milling drum 32 on drive configuration 46. Bolting moment bracing arrangement 82 extends along a component axis SA that is coaxial with drive axis A when bolting moment bracing arrangement is placed onto retaining bolt 78.

(66) Bolting moment bracing arrangement 82 is embodied as a fitover tool having an engagement region 82a (see FIG. 5) that is embodied, in the example depicted, as a recess having a shape complementary to tool engagement configuration 78c of retaining bolt 78, i.e. in this case as a hex socket polyhedron. Bolting moment bracing arrangement 82 can thus be placed axially, with its engagement region 82a, onto bolt head 78b of retaining bolt 78. A torque can thus be transferred in positively engaging fashion between bolt 78 and bolting moment bracing arrangement 82.

(67) Tool engagement configuration 78c of retaining bolt 78 thus constitutes a counterpart engagement region of engagement region 82a.

(68) Engagement region 82a is provided on an engagement portion 82b of bolting moment bracing arrangement 82. Two projections 82c and 82d, for example, project from that engagement portion 82b radially (with reference to component axis SA) in diametrical opposition.

(69) With bolting moment bracing arrangement 82 in the state, shown in FIG. 4, of being placed onto the central retaining bolt 78, bolting moment bracing arrangement 82 is radially externally surrounded by a counterpart bracing component 84 that is fixedly connected to side plate 30a of milling drum housing 30, for example by bolting. In the exemplifying embodiment depicted, counterpart bracing component 84 is arranged permanently on side plate 30a.

(70) Counterpart bracing component 84 comprises a central recess 84a through which head 78b of retaining bolt 78 is axially accessible externally, i.e. from outside machine body 13, in order to place bolting moment bracing arrangement 82 thereonto and pull it off therefrom.

(71) Recess 84a is (slightly) radially and (substantially) circumferentially larger than the corresponding respective radial and circumferential dimensions of engagement portion 82b having projections 82c and 82d. As a result, bolting moment bracing arrangement 82 can always be placed onto the retaining bolt regardless of the current rotational position of retaining bolt 78 that co-rotates with milling drum 32 during operation. Because, in the case of a hex head tool engagement configuration, the individual flat surfaces of tool engagement configuration are each rotated 60° with respect to their closest engagement surface in a circumferential direction, recess 84a preferably extends over at least 60° in the circumferential region that accommodates projections 82c and 82d.

(72) Surfaces 82e, facing in a circumferential direction, of projection 82c, and surfaces 82f, facing in a circumferential direction, of projection 82d form bracing regions of bolting moment bracing arrangement 82; of these, surfaces 82e can come into abutment against flanks 84b and surfaces 82f can come into abutment against flanks 84c, which delimit in a circumferential direction those regions of recess 84a in which projections 82c and 82d are received when bolting moment bracing arrangement 82 is in place. The two flanks 84b facing in a circumferential direction, and the two flanks 84c facing in a circumferential direction, of recess 84a thus form counterpart bracing regions of counterpart bracing component 84.

(73) It is thus possible, as necessary, to place bolting moment bracing arrangement 82 axially onto bolt head 78 without further preparatory handling, and to cause drive configuration 46 to rotate around drive axis A. This can occur either by way of internal combustion engine 39 and drive torque-transferring arrangement 54, or by way of a rotational drive (not depicted in the Figures) that can be coupled via coupling configuration 57 onto belt pulley 55 and thus indirectly onto drive configuration 46 for torque transfer. Merely for the sake of completeness, be it noted that coupling configuration 57 can be provided at any point on drive torque-transferring arrangement 54, so long as the drive configuration can be caused to rotate around drive axis A by actuating coupling configuration 57. The rotational drive that can be coupled to coupling configuration 57 can also be a manual rotational drive.

(74) Thanks to the planetary gearset arranged between drive torque-transferring arrangement 54 or coupling configuration 57 on the one hand, and cover 60 or its centering stem 60a in transmission housing 52 on the other hand, because of the large torque step-up ratio of the planetary gearset a torque of more than 2500 Nm or even more than 3000 Nm can be achieved with a comparatively low input-side torque, for example in the range from 250 to 300 Nm, at centering stem 60a that carries the internal thread for retaining bolt 78.

(75) After bolting moment bracing arrangement 82 is placed onto retaining bolt 78, a rotation of drive configuration 46 causes flanks 82e and 82f to come into abutment, depending on the direction of the rotational movement of drive configuration 46, against flanks 84b, 84c, facing in a circumferential direction, of recess 84a of counterpart bracing component 84. As a result of the positive engagement of engagement region 82a with bolt head 78b of the retaining bolt, a drive torque introduced into drive configuration 46 on the locating-bearing side of drive configuration 46 is braced by positively engaging abutment between projections 82c and 82d and counterpart bracing component 84 on the non-locating-bearing side of drive configuration 46. This ensures that as rotational driving of drive configuration 46 continues, a relative rotation occurs between retaining bolt 78 and drive configuration 46, and a helical movement of retaining bolt 78 relative to drive configuration 46 (in the example depicted, relative to centering stem 60a) thus occurs. Retaining bolt 78 can thus be tightened or loosened with an extremely high torque as a result of the bracing effect of bolting moment bracing arrangement 82 in interaction with counterpart bracing component 84.

(76) Axial positional retention of milling drum 32 relative to drive configuration 46 can be established and released without tools with the exception of bolting moment bracing arrangement 82.

(77) Counterpart bracing component 84 can remain permanently on machine body 13, more precisely on the end-located side wall 30a of milling drum housing 30.

(78) FIG. 4 is a view of the so-called “idle” side of earth working machine 10, i.e. that side of machine 10 which faces away from the viewer in FIG. 1. In FIG. 1 the viewer is looking at the oppositely located so-called “drive” side of machine 10. With machine 10 in the operational state, drive axial end 32a of milling drum 32 is located closer to the drive side of machine 10, and retention axial end 32 is closer to the idle side. The idle side of earth working machine 10 is usually the right side in a forward travel direction.

(79) Once axial positional retention has been established, drive configuration 46 can be driven a little way in the opposite rotation direction in order to release the abutment between flanks 82e, 82f of projections 82c and 82d of bolting moment bracing arrangement 82 and flanks 84b, 84c of counterpart bracing component 84, so that bolting moment bracing arrangement 82 can be manually pulled off axially from retaining bolt 78 with little force.

(80) In FIG. 5, dashed line 83 shows a possible physical separation between engagement portion 82b comprising projections 82c and 82d, and a radially inner core portion 82g comprising engagement region 82a. Engagement portion 82b and core portion 82g can be connected by a test apparatus, concealed by the aforesaid portions, that is embodied to allow a torque that is transferred between engagement portion 82b and core portion 82g to be capable of being checked. For example, the test apparatus can be a slip coupling that permits a torque transfer between engagement portion 82b and core portion 82g only up to a predetermined limit torque or a limit torque predeterminable by an adjustment action, and/or the test apparatus can output a signal, for example a sound, for example a click that is known from mechanical torque wrenches, when the limit torque is reached.

(81) The bolting moment bracing arrangement can, however, also be embodied in one piece.

(82) FIG. 6 depicts what is shown in FIGS. 2 and 3, with bolting moment bracing arrangement 82 placed onto bolt head 78b. Bolting moment bracing arrangement 82 is not sectioned.

(83) Projection 82d extends orthogonally to the drawing plane of FIG. 6 toward the viewer. Projection 82c is located behind the drawing plane in FIG. 6 and is concealed by engagement portion 82b. The counterpart bracing component is not shown in FIG. 6.

(84) FIG. 7 shows a second embodiment of working assembly 28.

(85) Components and component portions identical and functionally identical to those in the first embodiment are labeled in the second embodiment with the same reference characters but incremented by 100. The second embodiment of FIG. 7 is explained below only insofar as it differs from the first embodiment to an extent essential in terms of the invention.

(86) An essential modification of the second embodiment as compared with the previously described first embodiment is the conformation of centering stem 160a, which both acts as a centering configuration with respect to connecting flange 174 of milling drum 132 and serves as a bearing stem with respect to non-locating bearing 176.

(87) Counterpart centering configuration 174b is thus once again embodied as a recess. In contrast to the first embodiment, in the second exemplifying embodiment centering stem 160a not only projects axially into connecting flange 174 but passes axially completely through it.

(88) The result, as a consequence of the design, is that retaining bolt 178 can no longer impinge upon connecting flange 174 directly with axial force and displace it into the operating position, or retain milling drum 132 axially in the operating position via connecting flange 174. In the second embodiment, an axial force transfer between retaining bolt 178 and connecting flange 174 connected rigidly to milling drum 132 occurs with interposition of an auxiliary component 186 between bolt head 178b and connecting flange 174. Auxiliary component 186 is advantageously part of non-locating bearing 176, and serves in that context as a bracing component for the inner ring of the rolling bearing of non-locating bearing 176. Auxiliary component 186 is braced firstly against bolt head 178b, and then against connecting flange 174.

(89) What is stated above in conjunction with the sliding of non-locating bearing 76 or non-locating bearing assembly 85 onto bearing stem 74a and in conjunction with the pulling of non-locating bearing 76 or non-locating bearing assembly 85 off bearing stem 74a, by way of a pivoting movement of non-locating bearing 76 or non-locating bearing assembly 85 together with side door 30a, also applies to such sliding or pulling of non-locating bearing 176, in particular of non-locating bearing subassembly 185, respectively onto and off centering stem 160a, which interacts with auxiliary component 186 for rotational mounting of milling drum 132 in the same way as bearing stem 74a of the first embodiment.

(90) In addition, in the second embodiment a central hydraulic cylinder is not provided; instead several, for example three, hydraulic cylinders 162 are arranged with a (preferably equidistant) distribution around drive axis A in a circumferential direction and with a (preferably identical) radial spacing from drive axis A. Because each of the hydraulic cylinders 162 now needs to supply only a third of the force originally to be applied by central hydraulic cylinder 162 alone, each of the hydraulic cylinders 162 can advantageously end up being smaller than central hydraulic cylinder 162 of the first embodiment. There are, however, more of them.

(91) With hydraulic cylinders 162, milling drum 132 can again be moved axially in a direction toward the operating position, preferably into the operating position, with corresponding rear engagement components being arranged at the free longitudinal end of piston rod 163 (not depicted). Milling drum 132 can likewise be hydraulically moved axially out of the operating position.

(92) FIG. 8 shows, once again with reference to the first exemplifying embodiment, the advantageous use of a release component 88. With the aid of release component 88, milling drum 32 can be released axially out of its operating position from the locating bearing-side longitudinal end 46a of drive configuration 46, and pulled off, by way of a single central force engagement. Release component 88 can therefore be used, alternatively to hydraulic cylinder or cylinders 62 and 162, to move milling drum 32 out of the operating position.

(93) In FIG. 8, milling drum tube 42 and thus milling drum 32 have already been moved axially out of the operating position by the use of release component 88 so that centering stem 60a, constituting a centering configuration, no longer centers counterpart centering configuration 74b on connecting flange 74. Milling drum tube 42 is therefore no longer coaxial with drive axis A of drive configuration 46.

(94) The use of release component 88 on the drive assembly or milling assembly of FIG. 8 will be described not only with reference to FIG. 8 but also with reference to release component 88 shown in isolation in FIG. 9.

(95) As is evident from FIG. 9, release component 88 extends along a release component axis LA that, when utilization of release component 88 begins, is preferably coaxial with drive axis A of drive configuration 46 and with rotation axis R of milling drum 32.

(96) Release component 88 comprises a cooperating configuration 88a, for example in the form of an external thread, that can be bolted into bearing stem 74a of connecting flange 74. Bearing stem 74a has for that purpose a passthrough opening 74d, passing axially through it, through which counterpart centering configuration 74b in the form of a centering recess is reachable. At the longitudinal end region located remotely from centering recess 74b, bearing stem 74a has, in passthrough opening 74d, internal thread 74e that can be brought into bolting engagement with external thread 88a (cooperating configuration) of release component 88 so that release component 88 on the one hand can be secured on a component connected rigidly to milling drum 32, and on the other hand can be advanced axially relative thereto in defined fashion.

(97) At its longitudinal end that is located remotely from drive configuration 46 in the utilization state, i.e. when cooperating configuration 88a is bolted into internal thread 74e, release component 88 comprises a torque-transferring configuration 88b, for example in the form of a hex head tool engagement configuration and/or a hex socket tool engagement configuration. Preferably both tool engagement configurations are implemented on torque-transferring configuration 88b. Torque can be introduced into release component 88 at this torque-transferring configuration 88b while release component 88 is in use on earth working machine 10, in order to move said component axially relative to milling drum 32 with the aid of cooperating configuration 88a. A torque wrench or a mechanized torque wrench can engage onto torque-transferring configuration 88b.

(98) With a correspondingly axially protruding conformation of the counterpart bracing component or at least of a counterpart bracing region interacting with a bracing region of the bolting moment bracing arrangement, the bolting moment bracing arrangement can also be employed for torque bracing of the release component. The working apparatus can then be pushed off the drive configuration without tools, except for a release component and bolting moment bracing arrangement. At the least, the torque required for pushing it off does not necessarily have to be applied manually by an operator. Advantageously, the release component therefore comprises a tool engagement configuration (here: torque-transferring configuration 88b) identical to the bolt component of the bolt arrangement (here: retaining bolt 78), so that the engagement region of the bolting moment bracing arrangement also fits onto the tool engagement configuration of the release component.

(99) A shank portion 88c is adjacent to cooperating configuration 88a at the latter's longitudinal end located oppositely from torque-transferring configuration 88b. To reduce the weight of release component 88, shank portion 88c is preferably embodied in tubular fashion, i.e. is radially internally hollow. At that longitudinal end of shank portion 88c which is located oppositely from cooperating configuration 88a, release component 88 comprises an abutment portion 88d that can be embodied, for example, as a disk, in particular an annular disk, projecting radially beyond shank portion 88c. By advancing, release component 88 can be brought into abutting engagement at abutment portion 88d with drive configuration 46, here in particular into abutting engagement with a longitudinal end region of centering stem 60a of cover 60. Internal thread 74e is thus a fastening and/or advancing configuration within the meaning of the introductory part of the description.

(100) Once abutting engagement has been established between abutment portion 88d and drive configuration 46, connecting flange 74 that comprises fastening and/or advancing configuration 74e, and is fixedly connected to milling drum 32 or to milling drum tube 42, can be caused to move axially relative to drive configuration 46 by further introduction of torque into torque-transferring configuration 88b.

(101) Depending on the transfer of movement and force between cooperating configuration 88a and fastening and/or advancing configuration 74e, for example as a function of the pitch of the thread that is used, a large axial force, with which even a dirt-caked milling drum 32 can be axially released from drive configuration 46, can be generated at the site of the abutting engagement of abutment portion 88d against drive configuration 46.

(102) Once such a dirt jam has been released, i.e. once milling drum 32 has been made axially movable relative to drive configuration 46, the applied force necessary for axial removal of milling drum 32 from drive configuration 46 can be reduced to the usual level known for moving the massive components, and can be managed with usual methods known per se.

(103) As is evident from FIG. 8, release component 88 can also be embodied to be continuously hollow, i.e. as a tubular release component, so that drive configuration 46, or at least components thereof, can be accessible, even during utilization of release component 88, through an opening that passes through release component 88 along its release component axis LA. Like bolting moment bracing arrangement 82, release component 88 is preferably embodied in one piece.

(104) Lastly, FIG. 10 depicts a third embodiment that is intended simply to show that central retaining bolt 278 can also be bolted to piston rod 263 of hydraulic cylinder 262 for axial positional retention of milling drum 32 on drive configuration 46.

(105) Components and component portions identical and functionally identical to those of the first embodiment are labeled in the third embodiment with the same reference characters but incremented by 200. The third embodiment of FIG. 10 will be explained here only insofar as it differs from the first embodiment to an extent essential in terms of the invention.

(106) The third embodiment depicted in FIG. 10, having retaining bolt 278 threaded into piston rod 263, is of course also applicable to the design of the second embodiment in which centering stem 60a and bearing stem 74a are implemented in a single component. All that is then necessary is for bolt head 278b to brace against an auxiliary component that transfers force from bolt head 278b onto a component rigidly connected to milling drum 232, as is the case in FIG. 7 with auxiliary component 186. A component that is present in any case, for example a portion of non-locating bearing 276, is once again preferably used as an auxiliary component.

(107) The approach in accordance with the third embodiment as shown in FIG. 10 has the advantage that milling drum 232 can be pulled axially onto the drive configuration and conveyed into the operating position, and also pushed axially off drive configuration 246 and removed from the operating position, using hydraulic cylinder 262. For both installation and deinstallation of milling drum 232, the axial forces required for the axial movement of milling drum 232 are furnished by hydraulic cylinder 262. Axial positional retention with the aforementioned very high torque is once again accomplished, as described in conjunction with FIGS. 4 to 7, thanks to bolting moment bracing arrangement 82, 182 that interacts with counterpart bracing component 84, and with an introduction of torque on the locating bearing side of drive configuration 246 either by internal combustion engine 39 or by a separate rotational drive (including a manual one, if desired) that, as has already been described above, can be temporarily couplable to a coupling configuration 57 (see FIG. 2) of the drive torque-transferring arrangement for torque transfer.

(108) A preferred embodiment of a bearing component 90 which makes it easier to slide a non-locating bearing 76, 176, 276, in particular a non-locating bearing assembly 85, 185, 285, onto a bearing stem 74a, 160a, 274a and to pull it off therefrom, by a pivoting movement together with a side door 30a, 130a, 230a, will be described below in conjunction with FIGS. 11A to 14.

(109) A bearing component 90 having a bearing stem 74a is shown by way of example. The statements made below for bearing stem 74a also apply to the conformation, interacting with bearing assembly 185, of centering stem 160a.

(110) FIG. 11A depicts a separately handleable bearing component 90 and shows in isolation, in a side view, connecting flange 74 already depicted in FIG. 6 having bearing stem 74a protruding therefrom. FIG. 11B shows the same bearing component 90 in a longitudinal section view that contains central bearing stem axis Z of bearing stem 74a. With milling drum 32 in the operational position, bearing stem axis Z ideally coincides collinearly with rotation axis R and with drive axis A.

(111) Bearing component 90, preferably embodied in one piece, radially externally comprises a plurality of passthrough openings 74f into which the aforementioned threaded studs 72 can be threaded in order to connect connecting flange 74, and thus bearing component 90, nonrotatably to connecting ring 70 and thus to milling drum tube 42. Passthrough openings 74, which alternatively but not preferably can also be blind openings, are preferably all located at the same radial distance from bearing stem axis Z, and are preferably at the same angular distance from one another (see FIG. 12).

(112) Three recesses 74c, for positively engaging torque-transferring reception as described above of pins 80 nonrotatably connected to cover 60, are preferably also embodied equidistantly in terms of angle but at a shorter distance from bearing stem axis Z than passthrough openings 74f.

(113) Bearing component 90 comprises, on its side having stem 74a, a circumferential projection 74i that is interrupted only by recesses 74c. As is evident from FIG. 6, this projection 74i serves to center bearing component 90 with reference to connecting ring 70. A comparatively small projection distance for projection 74i, as compared with the protrusion distance of stem 74a, is therefore sufficient.

(114) Bearing stem 74a comprises two cylindrical bearing surfaces 74g and 74h against which hollow-cylindrical counterpart bearing surfaces of non-locating bearing assembly 85, more precisely of auxiliary component 86, circumferentially abut when milling drum 32 is in the operational state. A first cylindrical bearing surface 74g is farther from connecting flange 74, which constitutes an exemplifying protrusion structure from which bearing stem 74a protrudes, than second cylindrical bearing surface 74h. With these two cylindrical bearing surfaces, milling drum 32 can be mounted with sufficient accuracy for rotation around rotation axis R. To make it easier to pull non-locating bearing assembly 85 off bearing stem 74a, and to slide it thereonto, by means of a pivoting movement of non-locating bearing assembly 85 together with side door 30a, first cylindrical bearing surface 74g has a smaller diameter than second cylindrical bearing surface 74h.

(115) As a very general principle, the two cylindrical bearing surfaces can have different axial lengths, the smaller-diameter cylindrical bearing surface, in this instance bearing surface 74g, then preferably being the axially longer one.

(116) Also preferably, the axial spacing ab between first cylindrical bearing surface 74g and second cylindrical bearing surface 74h is greater than the radial spacing rb between those surfaces.

(117) Bearing stem 74a preferably tapers toward its free longitudinal end 74k located remotely from protrusion structure 74, as a rule in steps because of cylindrical bearing surfaces 74g and 74h, the degree of taper preferably increasing with increasing distance from protrusion structure 74. The free longitudinal end 74k may be referred to as a first axial end 74k. An opposite end of the bearing component 90 from the first axial end 74k may be referred to as a second axial end. In the preferred embodiment of bearing component 90 or 90′ depicted in FIGS. 11 and 13, this becomes evident in the axial portion, relevant for sliding non-locating bearing assembly 85 on together with side door 30a during a pivoting movement, that extends from longitudinal end 74h1, located axially closer to protrusion structure 74, of second cylindrical bearing surface 74h to free longitudinal end 74k of bearing stem 74a. The bearing stem can be embodied in such a way that the degree of taper firstly decreases with increasing distance from protrusion structure 74 in a region located closer to protrusion structure 74 than to longitudinal end 74k, and increases, as the free axial longitudinal end 74k is approached, in a region located closer to longitudinal end 74k than to protrusion structure 74.

(118) This axial portion is embodied in such a way that a first notional cone K1, constituting a first osculating circle S1, comprises an outer circumferential line of free longitudinal end 74k. Cone K1 abuts tangentially against this first osculating circle S1, and extends from there toward first cylindrical bearing surface 74g. Cone K1 abuts tangentially against a second osculating circle S2 on the outer surface of bearing stem 74a. Osculating circle S2 is located axially between first osculating circle S1 and axial end 74g2, located closer to free longitudinal end 74k, of first cylindrical bearing surface 74g. First notional cone K1 has an opening angle α.

(119) A second notional cone K2 proceeds from axial end 74g2, located closer to free longitudinal end 74k, of first cylindrical bearing surface 74g, constituting its first osculating circle or starting circle S3, and extends to a second osculating circle S4 on the outer surface of bearing stem 74a, against which cone K2 abuts tangentially. This osculating circle S4 is located axially between axial end 74g2 and axial end 74h2, located closer to free longitudinal end 74k, of second cylindrical bearing surface 74h. Second notional cone K2 abuts tangentially against osculating circle S4 but not against osculating circle or starting circle S3, and has an opening angle β.

(120) Bearing stem 74a is embodied in such a way that the opening angle α of first notional cone K1 is larger than the opening angle β of second notional cone K2.

(121) First cylindrical bearing surface 74g extends axially from axial end 74g1 located closer to the protrusion structure, to axial end 74g2 located closer to free longitudinal end 74k. The distance between axial end 74g2, located closer to free longitudinal end 74k, of first cylindrical bearing surface 74g and free longitudinal end 74k can itself be shorter than the distance between the two axial ends 74h2 and 74g2 located closer to free longitudinal end 74k.

(122) A similar design is selected for the conformation of the counterpart centering configuration in the form of counterpart centering recess 74b. Counterpart centering recess 74b preferably has two recess portions 74b1 and 74b2 located axially one behind another in a protrusion direction of bearing stem 74a, i.e. the direction in which centering stem 60a penetrates into counterpart centering recess 74b.

(123) With milling drum 32 in the operational state, the larger-diameter main centering recess portion 74b1, which is located closer to drive axial end 32a of milling drum 32, provides the main centering, relative to drive configuration 46, of bearing configuration 90 and thus of that axial portion of milling drum 32 which is located closer to retention axial end 32b. The smaller-diameter pre-centering recess portion 74b2, located farther from drive axial end 32a, likewise provides pre-centering of milling drum 32 relative to drive configuration 46 before milling drum 32 reaches its operating position, for example in the preparation position located axially remotely from the operating position.

(124) Centering stem 60a preferably also comprises two axial portions having diameters of different sizes, the larger-diameter one of which, constituting main centering stem portion, is in abutment against the circumferential wall of main centering recess portion 74b1 when milling drum 32 is in the operating position. The smaller-diameter axial portion of centering stem 60a, constituting a pre-centering stem portion, has already begun to enter pre-centering recess portion 74b2 before the main centering stem portion is introduced into main centering recess portion 74b1. A larger radial clearance exists between the smaller-diameter pre-centering stem portion of centering stem 60a and the circumferential wall of pre-centering recess portion 74b2 than between the larger-diameter main centering stem portion of centering stem 60a and the circumferential wall of main centering recess portion 74b1. Centering recess 74b can thus be securely and reliably centered on centering stem 60a even if, at the beginning of a sliding-on movement of milling drum 32 onto drive configuration 46, a large positional discrepancy exists between bearing stem axis Z and a central longitudinal axis of centering stem 60a.

(125) To allow even a large positional discrepancy of this kind to be managed at the beginning of the sliding-on movement, pre-centering recess portion 74b2 is preferably embodied to be axially longer than main centering recess portion 74b1. Pre-centering recess portion 74b2 is preferably axially longer than main centering recess portion 74b1 by an amount that is greater than the difference value of the radial spacing sb between the two circumferential walls of centering recess portions 74b1 and 74b2. The axial spacing ib of the two centering recess portions 74b1 and 74b2 from one another is also preferably smaller than the radial spacing sb between their circumferential walls.

(126) Centering recess 74b therefore also tapers from its longitudinal end, located closer to drive axial end 32a, toward internal thread 74e. The degree of taper of centering recess 74b decreases with increasing axial distance from its opening located closer to drive axial end 32a.

(127) In accordance with a preferred embodiment depicted in FIGS. 11A and 11B, the taper of centering recess 74b is preferably such that a first virtual cone K3, which abuts respectively against the edges, located axially closest to drive axial end 32a, R1 of main centering recess portion 74b1 and R2 of pre-centering recess portion 74b2, has a larger opening angle γ than a second virtual cone K4 that abuts on the one hand against edge R2, located axially closest to drive axial end 32a, of pre-centering recess portion 74b2, and on the other hand against an edge R3, located closest to drive axial end 32a, of a radial shoulder 74d1, following pre-centering recess portion 74b2 axially in a penetration direction of centering stem 60a, of centering recess 74b or of passthrough opening 74d of which centering recess 74b is a part. The opening angle of second virtual cone K4 is labeled δ in FIG. 11b.

(128) In the exemplifying embodiment depicted, the opening angle γ of first virtual cone K3 is slightly (between approximately 2° and 7°) larger than the opening angle α of first notional cone K1 described above. The opening angle δ of second virtual cone K4 is furthermore slightly (approximately 2° to 4°) smaller than the opening angle β of second notional cone K2 described above.

(129) FIGS. 13 and 14 depict a modified embodiment of bearing component 90. Components and component portions identical and functionally identical to those in FIGS. 11 and 12 have the same reference characters in FIGS. 13 and 14 but with an apostrophe added. The modified embodiment of FIGS. 13 and 14 will be explained below only insofar as it differs from the embodiment of FIGS. 11 and 12, to the description of which reference is otherwise additionally made for an explanation of the embodiment of FIGS. 13 and 14.

(130) In the axial portion that extends from longitudinal end 74h1′, located closer to the drive axial end, of second cylindrical bearing surface 74h′ to free axial longitudinal end 74k′, bearing stem 74a′ of bearing component 90′ has qualitatively the same external conformation as bearing stem 74a of bearing component 90. The statements made with regard to bearing stem 74a of bearing component 90 of FIGS. 11 and 12 therefore also apply to bearing stem 74a′ of bearing component 90′ of FIGS. 13 and 14.

(131) Centering recess 74b′ also has qualitatively the same conformation as centering recess 74b of bearing component 90 of FIGS. 11 and 12. Here as well, the statements made with regard to bearing component 90 apply without modification to bearing component 90′.

(132) An essential difference between bearing components 90 and 90′ is that connecting flange 74′ of bearing component 90′ has a smaller diameter and a radial step 74m′.

(133) Radial step 74m′ is functionally similar to protrusion 74i of bearing component 90, but differs appreciably in terms of where it is arranged. A protrusion 74i is therefore not embodied on bearing component 90′ between connecting flange 74′ and bearing stem 74a′ that protrudes from it.

(134) As a result of radial step 74m′ embodied on that side of connecting flange 74′ which is located closer to drive axial end 32a, bearing component 90′ can be inserted, as depicted in FIG. 13A, into a complementarily stepped recess of connecting ring 70′ in such a way that the end face, located closer to retention axial end 32b, of connecting flange 74′, from which bearing stem 74a′ axially protrudes, can be arranged flush with an end face, facing in the same direction, of connecting ring 70′. Radial step 74m′ can furthermore be axially dimensioned in such a way that that longitudinal end of bearing component 90′ which is located closer to drive axial end 32a is also arranged flush with that end face of connecting ring 70 which faces in the same direction.

(135) Because of the smaller radial extent of connecting flange 74′, recesses 74c′ are not embodied entirely in bearing component 90′ but instead are apparent there only as arc-shaped sub-recesses that form a complete recess 74c, into which a pin 80 of drive configuration 46 can penetrate in torque-transferring fashion, only when supplemented with corresponding complementary sub-recesses in connecting ring 70′.

(136) Again because of the smaller radial extent of connecting flange 74′, passthrough openings 74f for fastening bearing component 90′ on connecting ring 70′ are located radially farther inward, so that they are only in portions arranged equidistantly from one another in a circumferential direction. No passthrough openings 74f′ are provided where sub-recesses 74c′ are embodied.

(137) Leaving aside the earth working machine claimed later on, the subject matters disclosed below, relating to a replaceable milling drum for an earth working machine, are also of interest to the Applicant as being worthy of protection. The Applicant reserves the right to claim one or several of the subject matters defined below at a later point in time:

(138) 1. A replaceable milling drum (32; 232) for an earth working machine (10) such as a road milling machine, recycler, stabilizer, or surface miner, which extends between a drive axial end (32a) and a retention axial end (32b; 232b) located oppositely from the drive axial end (32a) and is embodied to radially externally surround a drive configuration (46; 246) of the earth working machine (10) in the operationally mounted state, the milling drum (32; 132; 232) being retainable in its operational position, against axial displacement, by a central bolt arrangement (78; 278), accessible in the region of its retention axial end (32b; 232b), having a bolt axis collinear with the central apparatus axis (R) of the milling drum (32; 232),

(139) a bearing stem (74a; 74a′; 274a) located in a region closer to the retention axial end (32b; 232b) than to the drive axial end (32a) being provided, which stem protrudes from a protrusion structure (74; 74′; 274) carrying it and extends in an axial direction taperingly in a direction away from the drive axial end (32a), the bearing stem (74a; 74a′; 274a) comprising at least two cylindrical bearing surfaces (74g, 74h; 74g′, 74h′) at an axial distance from one another with respect to the central apparatus axis (R), which, with the milling drum (32; 232) in the operational state, are surrounded with zero clearance by hollow-cylindrical counterpart bearing surfaces of an earth working machine-side non-locating bearing (76; 276), the cylindrical bearing surface (74g; 74g′) located axially farther from the protrusion structure (74; 74′; 274) having a smaller diameter than the cylindrical bearing surface (74h; 74h′) located axially closer to the protrusion structure (74; 74′; 274), and/or

(140) the milling drum (32; 232) comprising, at a region located closer to the retention axial end (32b; 132b; 232b) than to the drive axial end (32a), a centering recess (74b; 74b′; 274), embodied for positive centering engagement and connected rigidly to the milling drum (32; 132; 232), which tapers in a direction away from the drive axial end (32a), the centering recess (74b; 74b′; 274) being embodied with an opening angle (γ, δ) that decreases in steps along its taper.

(141) 2. The replaceable milling drum (32; 232) according to subject matter 1, refined in that the centering recess (74b; 74b′; 274) is embodied on the bearing stem (74a; 74a′; 274a).

(142) 3. The replaceable milling drum (32; 232) according to subject matter 1 or 2, refined in that the axially tapering conformation of the bearing stem (74a; 74a′) is such that the opening angle (α, β) of two notional enveloping cones (K1, K2), which respectively abut tangentially against two osculating circles (S1, S2, S3, S4) located with an axial spacing from one another on the surface of bearing stem (74a; 74a′) and surround an axial portion, located between the osculating circles (S1, S2, S3, S4), of the bearing stem (74a′ 74a′), is smaller for cones (K2) of osculating circle pairs (S3, S4) located closer to the protrusion structure (74, 74′).

(143) 4. The replaceable milling drum (32; 232) according to subject matter 3, refined in that the opening angle (a) of a first notional cone (K1), whose first osculating circle (S1), located farther from the protrusion structure (74; 74′), is located at the axial longitudinal end (74k; 74k′) located remotely from the protrusion structure (74; 74′), and whose second osculating circle (S2), located closer to the protrusion structure (74; 74′), is located axially between the first osculating circle (S1) and that axial longitudinal end (74g2; 74g2′) of the first cylindrical surface (74g; 74g′) which is located closer to the free bearing stem longitudinal end (74k; 74k′), is at least 1.5 times, preferably at least 2.5 times as large as the opening angle (β) of a second notional cone (K2) whose first osculating circle (S3), located farther from the protrusion structure (74; 74′), is located at that axial longitudinal end (74g2; 74g2′) of the first cylindrical bearing surface (74g; 74g′) which is located closer to the free bearing stem longitudinal end (74k; 74k′).

(144) 5. The replaceable milling drum (32; 232) according to subject matter 4, refined in that the opening angle of the second notional cone is equal to 5° to 15°, particularly preferably 8° to 13°.

(145) 6. The replaceable milling drum (32; 232) according to one of the preceding subject matters, refined in that the centering recess (74b; 74b′; 274) comprises a main centering recess portion (74b1; 74b1′) located closer to the drive axial end (32a) and a pre-centering recess portion (74b2; 74b2′) located farther from the drive axial end (32a), such that a first virtual cone (K3) that abuts respectively against the edges (R1, R2), located axially closest to the drive axial end (32a), of the main centering recess portion (74b1; 74b1′) and of the pre-centering recess portion (74b2; 74b2′) has a larger opening angle (γ) than a second virtual cone (K4) that abuts on the one hand against the edge (R2), located axially closest to the drive axial end (32a), of the pre-centering recess portion (74b2; 74b2′) and on the other hand against an edge (R3), located closest to the drive axial end, of a recess (74d; 74d′) that axially follows the pre-centering recess portion (74b2; 74b2′) in a direction away from the drive axial end (32a) and of which the centering recess (74b; 74b′) is a part.

(146) 7. The replaceable milling drum (32; 232) according to subject matter 6, refined in that the opening angle (γ) of the first virtual cone (K3) is approximately 3 to 6 times, particularly preferably 4 to 5 times, larger than the opening angle (δ) of the second virtual cone (K4).

(147) 8. The replaceable milling drum (32; 232) according to subject matter 6 or 7, refined in that the opening angle (γ) of the first virtual cone (K3) is equal to between 20° and 40°, particularly preferably between 25° and 35°.

(148) 9. The replaceable milling drum (32; 232) according to one of subject matters 6 to 8, including subject matter 4, refined in that the opening angle (γ) of the first virtual cone (K3) is larger than the opening angle (α) of the first notional cone (K1) described above.

(149) 10. The replaceable milling drum (32; 232) according to one of subject matters 6 to 9, including subject matter 4, wherein the opening angle (δ) of the second virtual cone (K4) is smaller than the opening angle (3) of the second notional cone (K2) described above.