Boom working device and method for detecting loads acting on the boom

Abstract

In order to know the loads acting on the boom, the load measuring unit, in particular only one, is either on or in the boom, in particular fixed, or between the arm end of the boom and the head end of the working head facing it.

Claims

1. A boom working device (1) for attachment to a carrier vehicle (7), comprising: at least one boom (3, 4), a rear end (3b, 4b) of said at least one boom capable of being attached to the carrier vehicle (7), an arm end (18a) as a front end (3a, 4a) of the at least one boom (3, 4), a working head (2) attached to an arm end (18a) with a head end (18b) of said working head facing the arm end (18a), a load measuring unit (50) with at least one load sensor (51) capable of detecting loads acting on the at least one boom (3, 4), where the load measuring unit (50) is arranged at one of the following of: a location on the boom (3, 4), a location in the boom (3, 4), or, a location between the head end (18b) and the arm end (18a).

2. The boom working device according to claim 1, where the arm end (18a) is pivotable relative to a rest of the at least one boom (3, 4), by a Z-joint (12) about a Z-axis (Z) and/or by an X-joint (27) about an X-axis (Z), and/or the boom working device (1) comprises only one load measuring unit (50).

3. The boom working device according to claim 1, where the load measuring unit (50) can detect forces acting on the at least one boom (3, 4) in more than one direction, the load measuring unit (50) can measure forces and/or moments acting on the at least one boom (3, 4) in the X, Y and Z directions, and/or the load measuring unit (50) comprises a plurality of load sensors (51a, b) for detecting loads acting on the boom (3, 4).

4. The boom working device according to claim 1, where the load measuring unit (50) is arranged either: at the arm end (18a); in the arm end; or at a rest of the at least one boom (3, 4) either: behind a Z-joint (12) between the Z-joint (12) and an X-joint (27); behind the X-joint (27); or in the X-joint.

5. The boom working device according to claim 1, where the at least one boom (3, 4) is positively connected to the working head (2) via a removable connecting element (58), and the load measuring unit (50) is either: present on the connecting element (58), or is the connecting element (58).

6. The boom working device according to claim 1, where the head end (18b) is attached to the arm end (18a) so that the head end (18b) cannot rotate.

7. The boom working device according to claim 1, further comprising: at least one recognition sensor (52) for detecting the working head (2) where the at least one recognition sensor (52) is located: at the boom (3, 4), in the boom (3, 4), or between the head end (18b) and the arm end (18a).

8. The boom working device according to claim 1, where the boom working device further comprises at least one detection sensor (52) and the at least one detection sensor (52) and the one load sensor (51) are functionally adjusted, and/or the load measuring unit (50) comprises at least one detection sensor (52).

9. The boom working device according to claim 1, where the at least one load sensor (51) of the load measuring unit (50) is an electrical sensor capable of measuring a change in an electrical voltage and/or an electrical resistance, the load measuring unit (50) further comprises a strain gauge (57), and the strain gauge (57) is arranged in a recess in the arm end (18a) or in a remainder of the boom (3, 4).

10. The boom working device according to claim 1, further comprising: a plurality of strain gauges (57), where each individual strain gauge (57) is oriented differently from every other strain gauge (57), the plurality of strain gauges (57) are connected to each other by an electrical bridge circuit, and at least one pair of strain gauges (57) measures a bending load of the arm end (18a) and/or at least one other pair of strain gauges (57) measures a torsional load of the arm end (18a).

11. The boom working device according to claim 1, where the load measuring unit (50) further comprises: at least one load measuring bolt (53) which measures and outputs a force applied to the load measuring bolt (53) in at least one of the transverse directions to a direction of extension (53) of the at least one load measuring bolt (53) and/or in the direction of extension (53) thereof.

12. The boom working device according to claim 1, where the head end (18b) is attached to the arm end (18a) by a locking bolt (15) fixed to the arm end (18a), where the locking bolt (15) is a load measuring bolt (53).

13. The boom working device according to claim 1, where the head end (18b) is attached to the arm end (18a) by a removable connecting element (58) provided between the arm end (18a) and the head end (18b), where: the arm end (18a) has a bearing support (54, 56) with a first through opening (54a, 56a) on a surface of the bearing support (54, 56) directed towards the head end (18b), the head end (18b) has a bearing block (55) with a second through opening (55a) on a surface of the bearing block (55) directed towards the arm end (18a), a removable load measuring bolt (53) extends through the first through opening (54a, 56a) and the second through opening (55a).

14. The boom working device according to claim 1, further comprising: at least two load measuring bolts (53) extending in different transverse directions (X, Y) to a Z-direction.

15. The boom working device according to claim 1, further comprising a load measuring bolt (53), where: forces acting on the load measuring bolt (53) are measured in two radial planes of the load measuring bolt (53) axially spaced apart in a direction of extension (53), if the load measuring bolt (53) is used as a connecting element (58), then a first bearing supports (54) and a second bearing support (56) with aligned first and second through-openings (54a, 56a) are arranged between which a third bearing support (55) with a third through opening (55a) fits such that the first, second, and third through-openings (54a, 56a, 55a) are aligned to form a total through opening, the load measuring bolt (53) extends through the total through opening.

16. The boom working device according to claim 1, further comprising: at least one load sensor (51) arranged at the arm end (18a) of the boom (3, 4) without contact to the head end (18b) of the working head.

17. The boom working device according to claim 1, where the load measuring unit (50) further comprises: a cylindrical, ring-shaped force transducer (61), where the force transducer (61) is capable of measuring at least forces in an axial direction (61) of the force transducer (61) and/or torques about one of the transverse directions of said axial direction (61), and the force transducer is arranged with said axial direction (61) running in a longitudinal direction (10), between the arm end (18a) and the head end (18b).

18. A method for detecting loads acting on a boom (3, 4) of a boom working device (1) according to claim 1, the method comprising the steps of: measuring a load, where the load is acting: on the boom (3, 4), in the boom (3, 4), or between a head end (18b) of a working head (2) and an arm end (18a) of the boom (3, 4).

19. A self-propelled working machine comprising: a carrier vehicle (7), a boom working device (1), the boom working device (1) comprising: at least one boom (3, 4), comprising a plurality of positioning elements (60) capable of positioning any of a plurality of arm parts (3.1, 3.2, 3.3 or, 4.1, 4.2, 4.3, 4.4) relative to one another, a working head (2) attached to a free front end (3a, 4a) of the multi-part boom (3, 4), the at least one boom capable of coming into contact with the environment away from the carrier vehicle (7) during use, a load measuring unit (50) for measuring loads acting on the at least one boom (3, 4), and a control (1*) capable of controlling a plurality of actuators, where the control (1*) of the boom working device (1) controls the plurality of actuators according to signals received by the load measuring unit (50).

Description

c) Exemplary Embodiments

(1) Types of embodiments according to the invention are described in more detail below as examples. It shows:

(2) FIG. 1a, b: a known way of attaching a working head to the free end of a boom on a boom working unit in two different side views,

(3) FIG. 2a, b: a carrier vehicle with two boom mowers in front view and in top view,

(4) FIG. 3: one of the two mowing heads in enlarged single view in front view,

(5) FIG. 4a, b: a first embodiments of a load measuring unit at the boom of a boom working device in two different side views analogous to FIGS. 1a, b,

(6) FIG. 5: further designs of a load measuring unit at or in the boom of a boom working device in a side view analogous to FIG. 1a,

(7) FIG. 6a, b: a first embodiment of a load measuring unit between boom and working head for a boom working unit in side view as well as in top view on FIG. 6a,

(8) FIG. 7a, b: a second embodiment of a load measuring unit between boom and working head at a boom working unit in side view and in the view of FIG. 7a from below.

d) Detailed Description of the Invention

(9) FIGS. 1a, b show a common way of attaching an exchangeable working head 2 to the free end of an boom 4 of an extension working device:

(10) For attachmentseen in direction ofvof the working head 2 to be attached, shown in dashed line, is pushed towards the arm end 18a from the right as viewed in the direction of FIG. 1a in such a way that the locking pins 15 protruding on both sidessee FIG. 1bof the arm end 18a in one side area of the arm end enter a locking recess 26, which are formed by hook-shaped curved locking elements 20, which are formed at the head end 18b of the working head 2 facing the arm end 18a of the boom 4 and positioned accordingly.

(11) Arm end 18a and head end 18b must not yet be in the position with their surfaces facing each other, as the working head 2 can still be pivoted around the locking pins 15 in this state.

(12) The working head 2 is only positioned and fixed positively and in a fixed position to the boom 4 by screw connection 25 between arm end 18a and head end 18b, preferably on the other side of the arm end 18a facing away from the locking pin 15.

(13) FIGS. 1a, b also show a Z-joint 12 in the end area of the boom 4, with which the foremost arm part 4.3 of the jib arm 4 facing the working head 2 is mounted as joint part 12b opposite a joint part 12a non-rotatably attached to the arm end 18a about a Z-axis corresponding to the direction of extension of this arm part 4.3 and/or mostly perpendicular to the parting plane or contact surface between arm end 18a and head end 18b.

(14) In this case, the pivoting is effected by means of two positioning elements 60 in the form of hydraulic cylinders, one end of which acts on the arm part 4.3, joint part 12.b, at different points of the circumference.

(15) FIGS. 2a, b as well as FIG. 3 show a typical application of such a mounting on the basis of a mowing vehicle in the form of a carrier vehicle 7 with two mowing heads 2a, b as working heads during operation, each supported by a boom 3, 4 at its free front end:

(16) Each mowing head 2a or 2b is driven by a mowing head motor 22 mounted on it.

(17) Both booms 3, 4 are attached with their rear end to a stem 8 attached to the front of the carrier vehicle 7, in that the stem 8 carries a transverse offset rail 5 on its front side, along each of which a sliding shoe 23, 24 can be moved in transverse direction 19 and can be moved in a controlled manner during operation. One of the booms 4, 3 is attached to each sliding shoe 23, 24.

(18) The booms 3, 4 each consist of several arm parts:

(19) For example, the boom 4 consists of an arm part 4.1, which rises from the sliding shoe 23 approximately in the direction of vertical 11 and can be rotated around a vertical axis and from the free end of which another arm part 4.2 projects and can be rotated around a transverse axis and, analogously, another arm part 4.3.

(20) The angular position of the arm parts to each other is controlled by hydraulic cylinders arranged in between, whereby the respective mowing heads 2a, b, which are additionally articulated around a Z-joint 12 at the front end of the boom 4, can be adjusted to any desired position with regard to direction of travel 10 (X-direction), horizontal cross direction 19 (Y-direction) here towards, as well as rotational position around the Z-axis. By means of a usually existing further X-joint in the boom 3, 4 near its free end, each mowing head 2a, b is additionally pivotable around the direction of travel 10, the X-axis, and can thus be pivoted around all three spatial directions and positioned in all 3 spatial directions as far as the dimensions of the boom 3, 4 allow.

(21) As best shown in FIG. 2a, the operator sitting in the driver's cab 6 of the carrier vehicle 7 controls the mowing heads 2a, b in such a way that the mowing head 2a mows an edge strip area immediately next to the carrier vehicle 7 and is positioned in front of the front end 8 of the carrier vehicle 7, while the mowing head 2b mows the edge area adjacent to it on the side, which is further outwards in relation to the carrier vehicle 7, and is positioned behind the first mowing head 2a in direction of travel 10.

(22) Due to this division, obstacles 9, which are in the area between the mowing widths of the two mowing heads 2a, b, such as road marker posts, can also be mowed around on both sides.

(23) For this purpose, there is usually a feeler bar 21 on the front edge of the front mower head 2a, which is swivelled towards the mower head 2a when striking such an obstacle 9 and thus causes this mower head 2a to fold in around the Z-joint located on the vehicle-side face of this mower head 2a in relation to the boom 3 carrying it.

(24) FIGS. 2a, b also show a display element 13 in the driver's cab 6 in the operator's field of vision, on which the measured loads can be output.

(25) FIG. 3 shows the mower head 2b working further outwards in an enlarged individual view, including the Z-joint 12b, whereby the necessary positioning elements 60 are not shown:

(26) This mowing head 2b has a housing 16, which is attached in the transverse center via this Z-joint 12 to the free end of the boom 4 so that it can swivel around the Z-axis, which is usually a vertical axis.

(27) Inside the housing 16, which is open at the bottom, a blade shaft 17 is mounted with each of its two ends around a blade shaft axis 17 in a front flange of the housing 16.

(28) FIGS. 4a, b show a 1st design and arrangement of a load measuring unit 50 for measuring the loads on the boom 4 when the working head 2 is attached to the boom 4 according to FIGS. 1a, b, with the measuring unit 50 arranged on the boom 4:

(29) The two locking pins 15or even just oneare embodied as load measuring bolts 53 and measure the loads acting on these pins.

(30) On or in each of the load-measuring bolts 53, preferably strain gauges 57 are arranged for this purpose, preferably distributed over the circumference, preferably several, in particular in each case in the axial length region, in that the locking elements 20 rest against the locking pin 15, which is designed as a load-measuring bolt 53, so that each of the load-measuring bolts 53 can measure loads occurring on it in the two transverse directions to its longitudinal direction 53.

(31) By appropriate electronic interconnection of the signals of the strain gages 57, not only forces in these two transverse directions can be measured, but also moments around these two transverse directions and/or around its longitudinal direction 53 if required.

(32) In a side view, FIG. 5 shows further positions where a load measuring unit 50 can be arranged on or in the outrigger arm 4, in which case an X-joint 27 is shown upstream, i.e. on the side of the Z-joint 12 facing away from the working head 2, by means of which two interconnected arm parts 4.3 and 4.4 can be swivelled relative to each other about the X-direction in the end area of the outrigger arm 4, and thus also the working head 2:

(33) The load measuring unit 50 may consist of one or preferably several strain gauges 57then electronically connected to each other via an evaluation circuitor may comprise one or several load measuring bolts 53no matter according to which functional principle they functionor may be embodied in any other way, in particular as shown in Figures Ga, b or FIGS. 7a, b, but with a different positioning, and in particular may have any type of load sensors 51.

(34) Possible positions for arranging such a load measuring unit 50individually or in totalare shown: at or in the arm end 18a, thus before, so to speak downstream, of the Z-joint 12, at or in the remaining boom 4 behind, so to speak upstream of the Z-joint 12, especially downstream and/or upstream of the X-joint 27, for example also between Z-joint 12 and X-joint 27.

(35) FIGS. 6a, b and 7a, b, on the other hand, show an arrangement of the load measuring unit 50 between boom 4 and working head 2, i.e. especially between arm end 18a and head end 18b:

(36) According to Figures Ga, b, the load measuring unit 50 in the form of a solution that is simple in terms of handling consists of using a so-called ring-shaped force transducer 61 instead of individual load sensors and fixing it between the arm end 18a and the head end 18b, in particular by screwing it down.

(37) This is amostly cylindrical and/or plate-shapedcomponent 61 available on the market, which can measure forces, depending on the design, mostly in its axial direction and/or also in at least one of its two transverse directions to this, but above all can also measure torques around its longitudinal axis 61.

(38) In this case, such a ring-shaped force transducer 61 must only be screwed between the e.g. plate-shaped arm end 18a and the e.g. also mostly plate-shaped head end 18b, and the signal line 61a leading away from the ring-shaped force transducer 61 must be connected to the control 1* of the boom working device 1.

(39) FIGS. 7a, b show another design of the load measuring unit 50 arranged between the boom 4 and working head 2, here between arm end 18a and head end 18b:

(40) The load measuring unit comprises 50 load measuring bolts 53, which are pushed through alternate through-holes of bearing supports, whereby in this case three bearing supports 54, 55, 56 are arranged in series.

(41) As FIG. 7a shows, the two bearing supports 54, 56 are attached to the arm end 18a of the boom 4 and project from there towards the head end 18b of the working head 2, while the bearing support 55 is attached inversely to the head end 18b, on the side facing the arm end 18a.

(42) The bearing support 55 projects between the other two bearing supports 54, 56 in such a way that the through-openings 54a, 55a, 56a in each of the bearing pedestals are aligned with each other, so that the load bolt 53, which fits exactly in there, extends through all three and thus connects the arm end 18a to the arm end 18b at one point.

(43) In the axial direction, axial spacer rings 59 are arranged between the bearing supports 54, 55, 56, which position the bearing blocks and thus the arm end 18a and head end 18b against each other in the axial direction of the load measuring bolts 53.

(44) With only one such connection, this would be a still pivoting connection.

(45) For this reasonas especially shown in the view of FIG. 7btwo such load measuring bolts 53 are arranged as described between the arm end 18a and the head end 18b, whereby their longitudinal extensions 53 are not aligned with each other but cross each other, especially at right angles.

(46) The load measuring bolts 53 thus also serve here as positive-locking connecting elements 58 between head end 18b and arm end 18a.

LIST OF REFERENCE SIGNS

(47) 1 boom working device 1* control 2, 2a, b working head, mowing head 3, 4 boom 3a front end 3b back end 3.1/.2/.3 arm piece 4a front end 4b back end 4.1/.2/.3/.4 arm piece 5 cross offset rail 6 driver's cab 7 carrier vehicle 8 stem 9 obstacle 10 direction of travel 11 vertical 12 z-joint 12a, 12b hinge part 13 feeler roller 14 feeler roller 15 locking pin 16 housing 17 blade shaft 17 blade shaft axis 18a arm end 18b head end 19 cross direction 20 locking element 21 feeler bar 22 mowing head motor 23 sliding shoe 24 sliding shoe 25 screw connection 26 locking recess 27 x-joint 50 load measuring unit 51 load sensor 52 detection sensor 53 load measuring bolt 53 longitudinal direction 54 bearing support 54a through opening 55 bearing support 55a through opening 56 bearing support 56a through opening 57 strain gauges 58 connecting element 59 spacer ring 60 positioning element 61 ring-shaped force transducer 61a signal line