DRIVE ARRANGEMENT FOR THE DISPLACEMENT OF A CONTACTING DEVICE AS WELL AS CONTACTING DEVICE AND USE THEREOF

Abstract

A drive arrangement for displacing a contacting device from a raised position to a lowered position includes a four-joint linkage having first, second and third arms interconnected such as to displace the contacting device as the first, second and third arms pivot. An actuator is connected via an actuating lever to the first arm and acted upon by a spring force which counteracts an actuating force applied by the actuator on the actuating lever. The actuating lever is pivotally connected to the first arm and supportable on the first arm via a catch when the first arm is displaced into a raised position and detachable from the first arm when the first arm is displaced into a lowered position, so that the actuating lever assumes a release position in the lowered position of the contacting device, with the contacting device maintained in the lowered position by its weight force.

Claims

1-11. (canceled)

12. A drive arrangement for displacing a contacting device from a raised position to a lowered position, said drive arrangement comprising: a four-joint linkage comprising a first arm, a second arm, and a third arm, said third arm having a free end for attachment of the contacting device, said first, second and third arms connected to one another such as to displace the contacting device as the first, second and third arms pivot; an actuator; and an actuating lever connecting the actuator to the first arm and acted upon by a spring force which counteracts an actuating force applied by the actuator on the actuating lever, said actuating lever being pivotally connected to the first arm and supportable on the first arm via a catch when the first arm is displaced into a raised position and detachable from the first arm when the first arm is displaced into a lowered position, so that the actuating lever assumes a release position in the lowered position of the contacting device, with the contacting device maintained in the lowered position by its weight force.

13. The drive arrangement of claim 12, wherein the actuating force acts on the actuating lever at a distance from the spring force.

14. The drive arrangement of claim 12, wherein the catch is arranged on the actuating lever, and further comprising: a mounting associated with the catch for support; and an adjustable spacer arranged on the catch or on the mounting to adjust a distance between the catch and the mounting.

15. The drive arrangement of claim 12, wherein the first arm includes a first end distal from the third arm, said actuating lever being connected in an articulated manner to the first arm in an area of the first end.

16. The drive arrangement of claim 15, further comprising a bearing support arranged in the area of the first end of the first arm, said actuating lever being mounted on the bearing support in an articulated manner.

17. The drive arrangement of claim 16, further comprising a mounting associated with the catch for support, said mounting being arranged on the bearing support.

18. The drive arrangement of claim 12, wherein the actuator is designed as a linear drive.

19. The drive arrangement of claim 16, wherein the actuating lever is connected to the actuator via an articulated connection, with the spring force between a pivot axis of the articulated connection of the actuating lever with the actuator and a pivot axis between the actuating lever and the bearing support acting on the actuating lever.

20. The drive arrangement of claim 12, wherein the spring force is applied in a direction which is predominantly parallel to an effective direction of the actuator.

21. A contacting device, comprising a drive arrangement, said drive arrangement comprising a four-joint linkage comprising a first arm, a second arm, and a third arm, said third arm having a free end for attachment of the contacting device, said first, second and third arms connected to one another such as to displace the contacting device as the first, second and third arms pivot, an actuator, and an actuating lever connecting the actuator to the first arm and acted upon by a spring force which counteracts an actuating force applied by the actuator on the actuating lever, said actuating lever being pivotally connected to the first arm and supportable on the first arm via a catch when the first arm is displaced into a raised position and detachable from the first arm when the first arm is displaced into a lowered position, so that the actuating lever assumes a release position in the lowered position of the contacting device, with the contacting device maintained in the lowered position by its weight force.

22. The contacting device of claim 21, wherein the actuating force acts on the actuating lever at a distance from the spring force.

23. The contacting device of claim 21, wherein the catch is arranged on the actuating lever, said drive arrangement comprising a mounting associated with the catch for support; and an adjustable spacer arranged on the catch or on the mounting to adjust a distance between the catch and the mounting.

24. The contacting device of claim 21, wherein the first arm includes a first end distal from the third arm, said actuating lever being connected in an articulated manner to the first arm in an area of the first end.

25. The contacting device of claim 24, wherein the drive arrangement comprises a bearing support arranged in the area of the first end of the first arm, said actuating lever being mounted on the bearing support in an articulated manner.

26. The contacting device of claim 25, wherein the drive arrangement comprises a mounting associated with the catch for support, said mounting being arranged on the bearing support.

27. The contacting device of claim 21, wherein the actuator is designed as a linear drive.

28. The contacting device of claim 25, wherein the actuating lever is connected to the actuator via an articulated connection, with the spring force between a pivot axis of the articulated connection of the actuating lever with the actuator and a pivot axis between the actuating lever and the bearing support acting on the actuating lever.

29. The contacting device of claim 21, wherein the spring force is applied in a direction which is predominantly parallel to an effective direction of the actuator.

30. A method for establishing an electrically conductive contact between a contacting device and a counterpart disposed below the contacting device, said method comprising: attaching the contacting device to a free end of a four-joint linkage; connecting an actuator to the four-joint linkage via an actuating lever; applying a spring force on the actuating lever to counteract an actuating force applied by the actuator on the actuating lever; and displacing the actuating lever into a release position, so that the counterpart is connected to the contacting device predominantly under the influence of a weight force of the contacting device and the four-joint linkage.

Description

[0031] FIG. 1 a simplified illustration of a drive arrangement in a lowered position;

[0032] FIG. 2 a detail of the drive arrangement of FIG. 1;

[0033] FIG. 3 the drive arrangement of FIG. 1 in a lowered position, with the actuating lever in a release position;

[0034] FIG. 4 a detail of FIG. 3;

[0035] FIG. 5 the drive arrangement of FIGS. 1 to 4 in a higher position;

[0036] FIG. 6: a detail of FIG. 5;

[0037] FIG. 7: the drive arrangement of FIGS. 1 to 6 in the raised position;

[0038] FIG. 8: a detail of FIG. 7.

[0039] FIG. 1 shows a side view of a drive arrangement 1 for a contacting device 2, which is displaceable from a raised position to a lowered position as shown. The drive arrangement 1 is suspended and attached to a supporting frame, which is not shown in greater detail and is located above the drive arrangement 1. It has several arms which form a four-joint linkage. A first arm 3 is the main arm and has a main bearing 5 at its first, upper end 4. The main bearing 5 is connected to the frame in a manner not shown in greater detail. A second arm 6 has at its first, upper end a bearing 7, via which the second arm 6 is connected to the frame, and at the second, lower end a lower bearing 8. The first arm 3 also has such a lower bearing 9. Both lower bearings 8, 9 are arranged at a distance from one another and connected to one another in a pivotable manner via a third arm 10. The distance between the lower bearings 8, 9 is relatively small hi relation to the overall length of the third arm 10. As a result, a lower end 11 of the third arm 10, which lower end is connected to the contacting device 2, can be pivoted over a relatively large stroke range.

[0040] The upper bearing 7 of the second arm 6 and the main bearing 5 are stationary joints. The entire drive arrangement including the contacting device 2 is supported via these two bearings 5, 7, with the main load being borne by the first arm 3, while the second arm 6 is provided for kinematic reasons to guide the third arm 10 or the contacting device 2.

[0041] The drive arrangement 1 according to the invention includes an actuator 12. It involves a linear drive. It includes an actuating cylinder 13 in which a piston rod 14 is guided. The piston rod 14 is pivotally connected with a bearing on the actuating lever 15, with the actuating lever 15 being pivotally connected to the first arm 3 via a bearing support 16 by means of a further bearing. The bearing support 16 is connected in fixed rotative engagement with a bearing sleeve 17 of the bearing support 16, in particular welded. The bearing sleeve 17 is part of the first arm 3 and rotates about the main bearing 5 as the first arm 3 pivots. Accordingly, the angular position of the bearing support 16 with respect to the first arm 3 is the same at ail times.

[0042] The actuating lever 15 is further connected to a spring 18, which exerts a spring force F1 upon the actuating lever 15. The spring 18 and the actuator 12 are supported on the frame.

[0043] The actuator 12 exerts a force F2 upon the actuating lever 15. FIG. 2 shows an enlarged view of the area of the main bearing 5 of the drive arrangement 1. The main bearing 5 with the bearing sleeve 17 defines the pivot axis A for the bearing support 16, which is fixedly connected to the first arm 3. On the bearing support 16, the actuating lever 15 is pivotally connected with the bearing support 16 in the area of a pivot axis B. The further pivot axes C, D relate to the spring 18 and the drive unit 12. In an embodiment not shown in greater detail, the pivot axis B of the bearing support 16 coincides with the pivot axis A of the main bearing 5. The position of the pivot axis B in proximity to the main bearing 5 plays a minor role.

[0044] The actuating lever 15 is in contact with the bearing support 16 via two regions. The first contact involves the articulated connection in the pivot axis B. The second contact is between a catch 19 on the actuating lever 15 and a mounting 22 on the bearing support 16. As a result of this contact, the pivotal movement capability of the bearing support 16 is restricted in one direction, namely in the direction in which the spring force F1 acts.

[0045] In this exemplary embodiment, the mounting 22 is oriented parallel to a straight line G(AB) through the pivot axes A and B. Parallelism is not necessary required, however the position of the mounting 22 is such that the catch 19 can rest on it when the actuating lever 15 is pivoted.

[0046] A torque M(A)G acts on the arm 3 in the pivot axis A of the main bearing 5 due to the weight force G of the contacting device 2. This torque M(A)G is so great that the mounting 22 is pushed against catch 19.

[0047] A spacer 20 in the form of a screw bolt is arranged on the catch 19 to adjust the distance between the catch 19 and the mounting 22. When the distance is increased, the arm 3 can no longer pivot downwards to the extent as shown in FIG. 2. The spacer 20 can be used to determine the lower and upper end positions or the maximum lowered and raised positions.

[0048] When the piston rod 14 is retracted, the catch 19 forces the bearing support 16 into a counterclockwise rotational movement via the pressure on the mounting 22 and via the pull in the area of the pivot bearing B. The connection between the bearing support 16 and the bearing sleeve 17 causes the arm 3 to pivot counterclockwise and as a result the contacting device 2 is raised.

[0049] FIG. 3 shows the state of the drive arrangement 1 in the lowered position, but with the difference to FIG. 1, that the contacting device 2 rests against a counterpart 21. The contacting device 2 is therefore in a slightly raised position compared to FIG. 1. The third arm 10 is not pivoted quite as far as in the exemplary embodiment in FIG. 1. As a result, there are also different angular positions for the first arm 3 and the second arm 6. This in turn has an influence on the position of the actuating lever 15, as explained with reference to the enlarged illustration of FIG. 4.

[0050] Compared to FIG. 2, the piston rod 14 has not been extended any further. However, since the counterclockwise movement of arm 3 has also caused the bearing support 16 to pivot counterclockwise, the mounting 22 is no longer in contact with the catch 19. As a result, the straight line G(AB) between the two pivot bearings A and B is at a greater angle W1 in relation to the direction of the spring force F1 than in FIG. 1. However, the spring force F1 is not so great that the torque of the weight force M(A)G could be overcome to thereby lift the arm 3. This is due, i.a., to the very small distance between the pivot axes A and B and to the acute angle W1, which is less than 45°, The release position of the actuating lever 15, as illustrated in FIGS. 3 and 4, enables upon the counterpart 21 a contact force which is determined predominantly by the weight force.

[0051] FIGS. 5 and 6 show a situation in which the first arm 3 has been raised even further. The actuator 12 has not been extended or retracted any further, but has the same position as in FIG. 4, This illustration makes it clear that even when the contacting device 2 has been displaced almost completely upwards, it is still possible to generate a sufficient weight force G to ensure an electrical connection with a counterpart.

[0052] At the same time, these Figures can be used to explain the situation that can arise in the event of a failure of the supply energy for the actuator 12. In this case, the piston rod 14, as shown in the enlarged illustration of FIG. 6, is blocked. After the blockage has been released, the spring force F1 pulls the piston rod 14 back so that the angle W1 indicated in FIG. 6 is reduced to such an extent that the catch 19 on the actuating lever 15 is pivoted upwards in the drawing plane and comes to rest again upon the mounting 22 in order to maintain the arm 3 in the raised position.

[0053] FIGS. 7 and 8 finally show the fully raised position, in which the catch 19 again acts against the mounting 22. It is apparent that the piston rod 14 is now retracted, in the raised position, the entire drive arrangement 1 is extremely compact and provides a high clearance height below the drive arrangement 1.

REFERENCE SIGNS

[0054] 1—drive arrangement [0055] 2—contacting device [0056] 3—first arm [0057] 4—first end of 3 [0058] 5—main bearing [0059] 6—second arm [0060] 7—upper bearing of 6 [0061] 8—lower bearing of 6 [0062] 9—lower bearing of 3 [0063] 10—third arm [0064] 11—lower end of 10 [0065] 12—actuator [0066] 13—actuating cylinder of 12 [0067] 14—piston rod of 12 [0068] 15—actuating lever [0069] 16—bearing support [0070] 17—bearing sleeve of 5 [0071] 18—spring [0072] 19—catch on 15 [0073] 20—spacer on 19 [0074] 21—counterpart [0075] 22—mounting [0076] F1—spring force [0077] F2—actuating force [0078] G—weight force [0079] G(AB)—straight line through A and B [0080] M1—torque by F1 [0081] M(A)G m torque by G [0082] A—pivot axis of 5 [0083] B—pivot axis between 15 and 16 [0084] C—pivot axis between 15 and 18 [0085] D—pivot axis between 12 and 15 [0086] W1—angle between G (weight force) and F1