CLAMPING OR GRIPPING DEVICE WITH EXTENDED STROKE

Abstract

Clamping or gripping device with a main body, with guide portions provided on the main body, with jaws which are movable along the guide portions in a direction of movement, which can be moved between an inner stroke position and an outer end-of-stroke position, the jaws each having a row-of-teeth portion with, in each case, a length extending in the direction of movement, and with multiple pinions, the axes of rotation of which lie in a plane lying parallel to the respective row-of-teeth portions, the pinions interacting with the respective row-of-teeth portion to drive the jaws.

Claims

1. Clamping or gripping device with a main body, with guide portions provided on the main body, with jaws which are movable along the guide portions in a direction of movement, which can be moved between an inner stroke position and an outer end-of-stroke position, the jaws each having a row-of-teeth portion with, in each case, a length extending in the direction of movement, and with multiple pinions (21, 22, 23; 51, 52), the axes of rotation of which lie in a plane lying parallel to the respective row-of-teeth portions, the pinions interacting with the respective row-of-teeth portion to drive the jaws, the axes of rotation of the pinions being spaced apart at a distance from one another, characterized in that the lengths of the guide portions, the lengths of the row-of-teeth portions and the distance a between the adjacent pinions being chosen such that, in the outer end-of-stroke position, one pinion interacts with only one row-of-teeth portion and another pinion interacts with only the other row-of-teeth portion, and in that at least two pinions interact with one row-of-teeth portion in one of the inner stroke positions.

2. Clamping or gripping device according to claim 1, characterized in that the length of the row-of-teeth portions is in the range of 1.0 to 2.0 times the distance a between the axes of rotation of adjacent pinions.

3. Clamping or gripping device according to claim 1, characterized in that the length of the guide portions is in the range of 2 to 6 times the length l of the row-of-teeth portions.

4. Clamping or gripping device according to claim 1, characterized in that two pinions are provided with the row-of-teeth portions in the inner stroke position interacting with both pinions.

5. Clamping or gripping device according to claim 1, characterized in that three pinions are provided with the row-of-teeth portions in the inner stroke position interacting only the middle pinion.

6. Clamping or gripping device according to claim 1, characterized in that each pinion is provided on a shaft and that each shaft comprises a gear which protrudes from the associated pinion in the radial direction.

7. Clamping or gripping device according to claim 1, characterized in that two adjacent gear wheels are coupled to one another in terms of movement via a coupling gear.

8. Clamping or gripping device according to claim 6, characterized in that a drive shaft (42) is provided with a drive pinion (44) which interacts with a gear or a coupling gear for driving the shafts.

9. Clamping or gripping device according to claim 1, characterized in that the guide portions are designed as guide strips with guide surfaces provided on two side walls facing away from one another, with the side walls with the guide surfaces being arranged to run parallel to a plane spanned by the axes of rotation of the pinions.

10. Clamping or gripping device according to claim 1, characterized in that the guide portions are designed as guide strips with guide surfaces provided on two side walls facing away from one another, with the side walls with the guide surfaces being arranged to run perpendicular to a plane spanned by the axes of rotation of the pinions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the drawings:

[0020] FIG. 1 is a gripping device viewed obliquely from below;

[0021] FIG. 2 is a cross section through the gripping device, according to FIG. 1, in a plane running through the jaws in the middle position or the inner stroke position of the jaws;

[0022] FIG. 3 is the section according to FIG. 2 in an intermediate stroke position;

[0023] FIG. 4 is the section according to FIG. 2 in an outer end-of-stroke position;

[0024] FIG. 5 is a cross section through the gripping device, according to FIG. 1, in a plane lying under the jaws;

[0025] FIG. 6 is a cross section through a second embodiment of a gripping device in a plane running through the jaws in the middle position or inner stroke position and

[0026] FIG. 7 is a cross section corresponding to FIG. 6 in an outer end-of-stroke position.

DETAILED DESCRIPTION

[0027] FIG. 1 is an illustration of a gripping device 10 comprising a main body 12 on which two guide portions 14 running parallel to one another are provided. The main body 12 is only indicated by dashed lines, and only one guide portion 14 is identified with a jaw 16 that is movable along the guide portion 14.

[0028] The guide portions 14, which run parallel to one another, and the two jaws 16, 17 can be clearly seen in FIGS. 2 to 4. According to the invention, three jaws can also be provided, which are then arranged so that they can be moved centrally toward or away from one another.

[0029] In the illustration according to FIG. 1, top jaws 18 are shown which can be fastened to the jaws 16, 17. With the top jaws 18, components not shown in the figures can be gripped or clamped directly or with the interposition of gripping fingers.

[0030] The jaws 16, 17 are movably arranged on the guide portions 14 between a middle position or inner stroke position, as shown in FIG. 2, and two outer end-of-stroke positions, one of which is shown in FIG. 4. Starting from the middle position, the jaws 16, 17 can consequently, on the one hand, move in the respective direction of movement 19.1. into the outer end-of-stroke position shown in FIG. 4 and, on the other hand, in the respective movement direction 19.2 into a second, outer end-of-stroke position.

[0031] The two jaws 16, 17 each have row-of-teeth portions 20 on the sides facing each other. The row-of-teeth portions 20 each have a length l extending in the direction of movement 19. The guide portions 14 have a length s that is likewise extending in the direction of movement 19.

[0032] As is clear from FIGS. 1 to 4, the gripping device 10 has a total of three pinions 21, 22 and 23, the axes of rotation 24 of which are arranged in a center plane E lying parallel to the row-of-teeth portions 20 and also between the row-of-teeth portions 20. The axis of rotation 24 of the adjacent pinions 21, 22 and 23 each have a distance a. The jaws 16, 17 are ultimately moved from the middle position into the respective outer end-of-stroke position via an interaction of the pinions 21, 22 and 23 with the row-of-teeth portions 20.

[0033] As is clear from FIGS. 2, 3 and 4, the length l of the row-of-teeth portions 20 is selected such that it is in the range of 1.2 to 1.5 times the distance a. Furthermore, the length s of the guide portions is selected such that it is in the range of 2 to 6 times and preferably in the range of 3 to 4 times, the length l of the row-of-teeth portions 20. This means that, in the inner middle position shown in FIG. 2, only the middle pinion 22 interacts with both row-of-teeth portions 20 of the two jaws 16, 17. When the jaws 16, 17 are displaced in the direction of the one outer end-of-stroke position, the jaw 16 therefore first moves to the left in the direction of movement 19.1, and the jaw 17 moves to the right in the direction of movement 19.2, as shown in FIG. 3. In this intermediate stroke position, the pinions 21 and 22 interact with the row-of-teeth portion 20 of the jaw 16. The pinions 22 and 23 interact with the row-of-teeth portion 20 of the jaw 17. If the jaws 16 or 17 are moved further in the direction of movement 19.1 or 19.2, the middle pinion 22 is pulled out of the row-of-teeth portions 20 of the two jaws 16, 17.

[0034] The position of the pinions 21, 22, 23, their spacing a and the length l of the rows of teeth are advantageously selected such that the row-of-teeth portions 20 are then in engagement with two pinions 21, 22 or 22, 23 when the respective jaw 16, 17 is in the nominal gripping range. The nominal gripping range is the range in which the jaws 16, 17 are regularly located in order to grip objects. In this respect, it is ensured that, in this range, each row-of-teeth portion 20 and thus each jaw 16, 17 interacts reliably with two pinions 21, 22 and 22, 23 so that high gripping forces can be reliably transmitted as well.

[0035] In the outer end-of-stroke position shown in FIG. 4, the pinion 21 only interacts with the row-of-teeth portion 20 of the jaw 16, and the pinion 23 only interacts with the other row-of-teeth portion 20 of the jaw 17. The row-of-teeth portions 20 of the jaws 16 and 17 are consequently handed over to the outer pinions 21, 23 before the outer end-of-stroke position is reached. Overall, this results in an expansion of the maximum stroke and, at the same time, a compact gripping device.

[0036] FIG. 5 is an illustration of a cross section through the gripping device 10 in a plane which lies below the jaws 16, 17 or their row-of-teeth portions 20. The three pinions 21, 22 and 23, which, as is also clear from FIG. 1, are each provided on a shaft 31, 32 and 33, can be clearly seen. Each of the shafts 31, 32 and 33 not only has a respective pinion portion for the respective pinion 21, 22, 23 but also a gear portion on which one gear 38 each is provided. The gears 38 protrude from the respective pinions 21, 22, 23 in the radial direction. Coupling gears 40 are provided for the synchronous movement coupling of the shafts 31, 32, 33. As FIG. 1 makes clear, a drive shaft 42, which has a drive pinion 44 shown in FIG. 5, which interacts with the pinion 22, is provided to drive the pinions 21, 22, 23. The drive shaft 42 is driven, in particular, by an electric motor, not shown in the figures, and it is possible for one or more gear units to be provided between the drive shaft 42 and the driven shaft of the electric motor.

[0037] In an embodiment that is not shown, it is conceivable that the coupling gears 40 do not engage in a gear 38 formed separately from the respective pinion 21, 22, 23 but instead interact directly with the respective pinion 21, 22, 23. The axes of rotation of the coupling gears 40 can, in particular, also lie in the plane E.

[0038] In FIGS. 6 and 7, a gripping device 50 is shown which, in contrast to the gripping device 10 according to FIGS. 1 to 5, has only two pinions 51 and 52. Components corresponding to the gripping device 10 are provided with corresponding reference numerals.

[0039] As in the case of the gripping device 10, the pinions 51, 52 are each located on a shaft on which a larger gear 38 is provided in addition to the respective pinion 51, 52. The two gears 38 mesh with the drive pinion 44.

[0040] As is clear from FIG. 6, the arrangement in the middle position or inner stroke position is such that the row-of-teeth portions 20 of both jaws 16, 17 are in engagement with the respective pinion 51, 52. The length l of the row-of-teeth portions 20 is typically in the range from 1.2 to 1.5 times the distance a between the axes of rotation 24 of the two pinions 51, 52.

[0041] In the one outer end-of-stroke position shown in FIG. 7, the arrangement is such that only one pinion 51, 52 interacts in each case with only one of the row-of-teeth portions 20. Furthermore, the arrangement is such that the pinions 51, 52 are only in engagement with the last, inner teeth of the row-of-teeth portions 20. In the other end-of-stroke position, not shown, the respective other pinion 50, 51 is in operative connection with the respective other row-of-teeth portion 20.

[0042] As is clear from FIG. 1, the guide portions 14 are designed as guide strips with guide surfaces 54 provided on two side walls facing away from one another. The side walls with the guide surfaces 54 are arranged such that they run perpendicular to the plane E in the embodiment shown. In this way, a vertical guide is realized, which makes it possible to save space in the radial direction. However, it can also be provided that the side walls with the guide surfaces 54 are arranged such that they run parallel to the plane E, which causes a horizontal guide to be realized which is comparatively slim in the axial direction.

[0043] The gripping devices 10 and 50 have the advantage that they have a significantly larger jaw stroke compared to known gripping devices, whereby the row-of-teeth portions 20 each interact with one different number of pinions when the jaws 16, 17 are moved from the middle position or inner stroke position into the respective outer end-of-stroke position. Adjacent pinions 21, 22, 23 or 51, 52 consequently hand over the respective row-of-teeth portion 20 to the next pinion until the outer end-of-stroke is reached. In the respective outer end-of-stroke position, only one pinion 21, 23 or 51, 52 interacts with only one row-of-teeth portion 20.