FINISHING DEVICE

Abstract

A finishing device includes a finishing belt, a finishing belt holding device, a first drive configured to rotationally drive a workpiece about a workpiece axis, and a second drive configured to oscillate the workpiece and the finishing belt relative to another along the workpiece axis. The finishing belt holding device has a holding section configured to hold a portion of the finishing belt. The portion has an active area configured to finish a circumferential workpiece surface. The portion extends in a plane which is vertical when referring to the direction of gravity and extends in a horizontal direction when referring to the direction of gravity and when viewing in the running direction of the finishing belt. The finishing device includes a workpiece holding device defining a workpiece holding axis which is vertical when referring to the direction of gravity.

Claims

1. A finishing device, comprising: a finishing belt, a finishing belt holding device, a first drive configured to rotationally drive a workpiece about a workpiece axis, and a second drive configured to oscillate the workpiece and the finishing belt relative to another along the workpiece axis, wherein the finishing belt holding device has a holding section configured to hold a portion of the finishing belt, the portion having an active area configured to finish a circumferential workpiece surface, the portion extending in a plane which is vertical when referring to the direction of gravity and the portion extending in a horizontal direction when referring to the direction of gravity and when viewing in the running direction of the finishing belt, and wherein the finishing device includes a workpiece holding device defining a workpiece holding axis which is vertical when referring to the direction of gravity.

2. The finishing device according to claim 1, wherein the finishing belt holding device includes a supply of finishing belt which includes a supply roll which is rotatable about a supply roll axis which is vertical when referring to the direction of gravity.

3. The finishing device according to claim 1, wherein the finishing belt holding device includes a driving unit configured to drive the finishing belt in a driving direction which is horizontal when referring to the direction of gravity.

4. The finishing device according to claim 1, wherein the finishing belt holding device includes a holding plate extending in a holding plate plane which is horizontal when referring to the direction of gravity.

5. The finishing device according to claim 4, wherein the holding plate is pivotable between a working position and a maintenance position in a horizontal direction about a pivot axis which is vertical when referring to the direction of gravity.

6. The finishing device according to claim 5, further comprising a guiding device which—in the working position of the holding plate—compensates for at least one of a vertical misalignment or a deflection of the holding plate.

7. The finishing device according to claim 1, including multiple finishing belt holding devices with a first subset of the finishing belt holding devices being offset from a second subset of the finishing belt holding devices when referring to the circumference of the workpiece.

8. The finishing device according to claim 7, wherein the offset between the first subset and the second subset is an angle of about 180°.

9. The finishing device according to claim 7, wherein the finishing belt holding devices of the first subset are offset from the finishing belt holding devices of the second subset when referring to the workpiece axis.

10. The finishing device according to claim 1, wherein at least one finishing belt handling device is configured to finish at least one workpiece surface extending in a workpiece plane which is perpendicular to the workpiece axis.

11. The finishing device according to claim 10, wherein the at least one finishing belt handling device is offset from the finishing belt holding device when referring to the circumference of the workpiece.

12. The finishing device according to claim 11, wherein the offset is an angle of about 90° or about 180°.

13. The finishing device according to claim 10, wherein the at least one finishing belt handling device is movable between a working position and a maintenance position along an axis which is horizontal when referring to the direction of gravity.

14. The finishing device according to claim 13, further comprising a drive configured to drive the at least one finishing belt handling device along the axis.

15. The finishing device according to claim 10, wherein at least a working area of the at least one finishing belt handling device is movable along an axis which is vertical when referring to the direction of gravity.

16. The finishing device according to claim 15, wherein the finishing belt handling device is supported by a weight supporting device compensating for the weight of the finishing belt handling device.

17. The finishing device according to claim 10, further comprising a mass compensation device configured to compensate for the mass inertia of the finishing belt handling device.

18. The finishing device according to claim 1, further comprising a mass compensation device configured to compensate for the mass inertia of at least one of the first drive, the second drive, the workpiece holding device, or the workpiece.

19. The finishing device according to claim 1, further comprising a machine housing including housing parts which are movable between a working position and a maintenance position, and a drive for moving the housing parts.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0031] Embodiments of the invention are described hereinafter relative to the drawings, wherein:

[0032] FIG. 1 is a perspective view of an embodiment of a finishing device having a machine housing and interior parts;

[0033] FIG. 2 is a perspective view of some of the interior parts of the finishing device of FIG. 1, including finishing belt holding devices;

[0034] FIG. 3 is a perspective view of two subsets of finishing belt holding devices, the subsets being positioned in a maintenance position;

[0035] FIG. 4 is a perspective view of the subsets of FIG. 3, the subsets being positioned in a working position;

[0036] FIG. 5a is a perspective view of a finishing belt handling device of the device of FIG. 1, the finishing belt handling device being designed for the machining thrust faces of a workpiece, the finishing belt handling device being shown in its working position;

[0037] FIG. 5b is a perspective view corresponding to FIG. 5a, the finishing belt handling device being shown in its maintenance and loading position;

[0038] FIG. 6 is a perspective view of the two subsets of finishing belt holding devices and the finishing belt handling device; and

[0039] FIG. 7 is a perspective view of a large scale detail of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

[0040] In the drawings, reference sign 10 designates a machine tool in the form of a finishing device. The device 10 includes a machine frame 12 which is set up on a floor 14 and has a horizontal upper surface 16 delimiting the lower end of a workspace 18.

[0041] The workspace 18 is further limited towards the sides and towards the top by means of a machine housing 20. The housing 20 may include stationary housing elements 22 and movable housing parts 24. The movable housing parts 24 may be positioned in a maintenance position (FIG. 1) allowing for an easy access to the workspace 18. The movable housing parts 24 may also be positioned in a working position, in which the housing parts delimit a box-shaped workspace 18 and provide protection for an environment 26 of the device 10. For moving the housing parts 24, they may be mounted in a pivotable manner and handled manually or driven by means of a drive which may for example be electric.

[0042] When using the expressions “horizontal” and “vertical” in the context of the present invention, these expressions relate to the direction of gravity which is indicated in the drawing by means of an arrow 28. Thus, “vertical” means an orientation which is parallel to the direction of gravity 28 and “horizontal” means an orientation which is perpendicular to the direction of gravity 28. In a typical production environment, the floor 14 for setting up the device 10 will be horizontal such that the floor extends in a perpendicular direction with respect to the direction of gravity 28.

[0043] The workspace 18 accommodates a workpiece 30 (FIG. 2) which is to be finished. The workpiece 30 extends along a vertical workpiece axis 32 (FIGS. 1 and 2). During a finishing operation of the device 10, the workpiece 30 rotates around the axis 32 in a continuous manner and—at the same time—moves in an oscillating manner back and forth along the axis 32.

[0044] The device 10 includes parts shown in FIG. 2. When referring to the direction of the vertical axis 32, first parts 34 are arranged at a lower end and within machine frame 12. Middle parts 36 and upper parts 38 are arranged above the upper surface 16 and within the workspace 18 (FIG. 1).

[0045] First parts 34 include a first drive 40 for rotationally driving the workpiece 30 about the workpiece axis 32. First parts 34 also include a second drive 42 for oscillating the workpiece 30 back and forth along the workpiece axis 32.

[0046] The first drive 40 includes a workpiece holding element 44 which interacts with a lower end of the workpiece 30. At an upper end of the workpiece 30, the workpiece 30 is held by means of another workpiece holding element 46. In a particularly preferred embodiment, workpiece holding element 44 is part of head stock 48, and workpiece holding element 46 is part of a tail stock 50. Workpiece holding elements 44 and 46 together constitute a workpiece holding device 44, 46.

[0047] Head stock 48 and tail stock 50 may be mounted to a common carrier which oscillates back and forth by means of the second drive 42. It is also possible that the second drive 42 only acts on head stock 48 (and the associated drive 40) and that tail stock 50 follows the oscillating movement of head stock 48 and workpiece 30 by means of a pneumatic actor 52. Independent of the head stock 48 and the tail stock 50 being mounted on a common or on separate carriers, the workpiece holding device 44, 46 defines a workpiece holding axis 54 which is identical with the workpiece axis 32 when the workpiece 30 is mounted and held by means of the workpiece holding device 44, 46.

[0048] Middle parts 36 include a plurality of finishing belt holding devices 56. These holding devices 56 are arranged such that they include a first subset 56a of at least one finishing belt holding device 56, for example four or six finishing belt holding devices, and a second subset 56b also comprising at least one finishing belt holding device 56, for example four or six finishing belt holding devices 56. The subsets 56a and 56b are offset from one another when referring to the circumference of the workpiece 30. In the working position of the finishing belt holding devices 56, the angular offset between the first subset 56a and the second subset 56b is 180°, (FIG. 2).

[0049] Each finishing belt holding device 56 includes a holding plate 58 for holding parts explained in greater detail hereinafter. The holding plates 58 of each subset 56a, 56b are pivotably mounted about stationary pivot axes 60a, 60b, these axes each being defined by means of a column 62a, 62b.

[0050] The finishing belt holding devices 56 of a particular subset 56a or 56b are pivotable about the associated pivot axis 60a or 60b, either independently of one another or being connected to one another and thus being pivotable as a unit of a plurality of finishing belt holding devices 56.

[0051] By pivoting one or a plurality of finishing belt holding devices 56 about an associated pivot axis 60a, 60b, a finishing belt holding device 56 is movable between a maintenance position (FIG. 3) and a working position (FIGS. 2 and 4).

[0052] In FIG. 4, portions of the finishing belt holding devices 56 of the second subset 56b are not shown to better illustrate the design and functionality of a guiding device 64. It is preferred that the finishing device 10 includes one guiding device for each finishing belt holding device 56. Each guiding device 64 includes a receptacle 66 which interacts with a protrusion 68. One of the elements 66 and 68 is mounted in a stationary manner, for example a receptacle 66. The other element, for example the protrusion 68, is mounted in a movable manner and is stationary with respect to the holding plate 58 of a particular finishing belt holding device 56. In the maintenance position of a finishing belt holding device 56, the protrusion 68 and the receptacle 66 are separate from one another (FIG. 3). In the working position of a finishing belt holding device 56, the protrusion 68 interacts with the receptacle 66 in a form engaging manner such that a vertical position of the holding plate 58 is defined by means of the guiding device 64.

[0053] The protrusion 68 may have the shape of a wedge; the receptacle 66 may have a corresponding v-shaped notch.

[0054] The finishing device 10 may optionally include a finishing belt handling device 70 which is shown in greater detail in FIGS. 5a and 5b. The finishing belt handling device 70 includes a supply 72 for a finishing belt 74 which is guided such that in a working area 76 the abrasive, active side of the finishing belt 74 is orientated in two parallel planes which are perpendicular to the workpiece axis 32, such that corresponding workpiece surfaces such as thrust faces can be machined by means of finishing belt 74.

[0055] The finishing belt handling device 70 also includes a drive 78 for driving (pulling) finishing belt 74. The supply 72 and the drive 78 are mounted to a frame 80.

[0056] The working area 76 of the finishing belt 74 is defined by a front tip of a slide 81. The slide 81 is guided by means of a linear bearing 82 and thus movable along a vertical axis 83 with respect to the frame 80.

[0057] The weight of the frame 80 and the parts connected with it is supported by a base 84 which is supported and guided by a linear guiding 85. The linear guiding 85 is fixed with respect to the machine frame 12 and defines a horizontal axis 86 along which frame 80 is movable between a working position (FIG. 5a) and a retracted maintenance and unloading position (FIG. 5b) by means of a drive 87.

[0058] The drive 87 which may for example be a pneumatic cylinder 88 having a piston 89 which is connected to a connecting part 90 which is coupled to the base 84.

[0059] The slide 81 is guided along an axis 91 which is parallel to the horizontal axis 86 and which is defined by a stationary column 92. The slide 81 includes a bushing 93 which slidably engages column 92.

[0060] The finishing belt handling device 70 also includes a drive 94 for oscillating frame 80 and in particular slide 81 and its working area 76 in a horizontal direction along an oscillation axis 95. The drive 94 is fixed to base 84 and acts on an excenter unit 96 having a rod 97 which is connected to the frame 80. The frame 80 is movable along a horizontal axis 98 by means of a linear guiding 99 (FIG. 5b) which is effective between the base 84 and the frame 80.

[0061] The column 92 is connected to the head stock 48 by means of a connector 100. Due to this connection, a vertical oscillating movement of the head stock 48 (for example by means of second drive 42) is transferred the head stock 48 to column 92 and to the bushing 93 and to the slide 81 and to the working area 76, thereby driving the working area 76 in a vertical oscillating manner, as indicated with a double arrow (FIG. 5a). Because of the vertical linear bearing 82 effective between the slide 81 and the frame 80, the working area 76 can be driven in an oscillating manner along the horizontal axis 95 at the same time and independent of the vertical oscillating movement of the slide 81 and the associated working area 76.

[0062] When making use of the optional finishing belt handling device 70 it is preferred that this device is arranged such that it is offset from the finishing belt holding devices 56 of both subsets 56a and 56b when referring to the circumference of the workpiece 30. In a particularly preferred embodiment, the angular offset between the finishing belt handling device 70 and each of the subsets 56a, 56b is 90°, (FIG. 6).

[0063] As described above, each finishing belt holding device 56 includes a holding plate 58. Each finishing belt holding device 56 includes a supply 101 of finishing belt 102, in particular a supply roll 104 which is rotatable about a supply roll axis 106. The supply roll axis 106 is vertical and associated to the holding plate 58.

[0064] Each finishing belt holding device 56 also includes a driving unit 108 for driving (pulling) finishing belt 102 in a driving direction 109.

[0065] The finishing belt 102 is supplied by supply roll 104 and then guided to a pressing device 110 which includes a pressing head 112 which is movable with respect to a housing 114 along a horizontal moving axis 116 and which is also pivotable about a vertical axis in order to be able to follow a pin bearing which upon rotation of the workpiece 30 moves along an orbit around the workpiece axis 32.

[0066] In particular referring to FIG. 7, the finishing belt 102 of each finishing belt holding device 56 includes a holding section 118 for holding a portion 120 of a finishing belt 102, wherein an active area 122 of portion 120 is exposed to a circumferential workpiece surface 124 of the workpiece 30.

[0067] The portion 120 of finishing belt 102 extends in a vertical plane and, when referring to a running direction 126 of the finishing belt 102, in a horizontal direction. The running direction 126 of the finishing belt 102 is horizontal, corresponding to the vertical orientation of the supply roll axis 106.

[0068] During operation of the finishing device 10, the workpiece 30 is driven in a rotational direction 128 about workpiece axis 32, (FIG. 7). This rotational movement is caused by first drive 40 (FIG. 2). A linear oscillating movement 130 (FIG. 7) is imposed on the rotational movement 128. In particular, the oscillating movement 130 is a back and forth movement along workpiece axis 32 and caused by second drive 42 (FIG. 2).

[0069] During the machining of workpiece 30, the active area 122 of a portion 120 of a finishing belt 102 contacts a circumferential surface 124 of the workpiece 30. The circumferential surface 124 may for example be a pin bearing surface 132 (FIG. 7) or a main bearing surface 134.

[0070] It is preferred that a first subset 56a of finishing belt holding devices 56 is associated with a particular type of circumferential workpiece surfaces 124, for example with pin bearing surfaces 132. Accordingly, a second subset 56b of finishing belt holding devices 56 is associated with another type of circumferential workpiece surfaces 124, for example with main bearing surfaces 134.

[0071] The first subset 56a of finishing belt holding devices 56 may be associated with a first further drive (not shown) for oscillating the first subset 56a of finishing belt holding devices 56 in a vertical direction. Similarly, the second subset 56b of finishing belt holding devices 56 may be associated with a second further drive for oscillating the second subset 56b of finishing belt holding devices 56 in a vertical direction. Therefore, the handling devices 56 of a particular subset 56a and/or 56b may be driven in an oscillating manner and independently of second drive 42.

[0072] It is preferable that the first further drive and/or the second further drive provide for an oscillating movement of the handling devices 56 of subsets 56a and/or 56b, this movement having a lower frequency and a higher amplitude than the movement of the workpiece 30 caused by the second drive 42 which may take place at a higher frequency and a lower amplitude. However, it is also possible that the first further drive and/or the second further drive provide for an oscillating movement of the handling devices 56 of subsets 56a and/or 56b, this movement having a higher frequency and a lower amplitude than the movement of the workpiece 30 caused by the second drive 42 which may take place at a lower frequency and a higher amplitude.

[0073] When making use of an optional finishing belt handling device 70, exterior, abrasive sides of the finishing belt 74 of the finishing belt handling device 70, namely a lower side 136 and an upper side 138 of the working area 76, contact workpiece surfaces 140 which extend in planes perpendicular to the workpiece axis 32. The workpiece surfaces 140 may be thrust faces of a crankshaft. The lower side 136 and an upper side 138 are driven by drive 94 (FIGS. 5a and 5b) and move in an oscillating manner along the horizontal axis 95 as indicated by a double arrow in FIG. 7.

[0074] Since the active area 76 of the finishing belt handling device 70 is movable along a vertical axis 83 (FIGS. 5a and 5b) the active area 76 of the finishing belt handling device 70 can at least passively follow the oscillating movement 130 of the workpiece 30. When using a connector 100 (FIGS. 5a and 5b), the active area 76 is actively driven in a vertical oscillating manner and synchronously with the workpiece 30. In both cases, i.e. independent of a connector 100 being used or not, the active area 76 can machine workpiece surfaces 140 at the same time as the finishing of the circumferential workpiece surfaces 124 takes place by means of the finishing belts 102 of finishing belt holding devices 56.

[0075] Due to the vertical concept of the device 10, the footprint of the machine frame 12 and all parts of the device which are arranged on top of the machine frame 12 is small compared to conventional horizontal concepts known from prior art.