Gripping or clamping device having an actuator

Abstract

The invention relates to a gripping or clamping device having an actuator, including a drive driving the actuator, and at least one jaw that is motion-coupled with the actuator. The actuator includes a spindle having a threaded portion, wherein for the purpose of motion coupling, an active portion meshing the threaded portion is arranged on the jaw side.

Claims

1. Gripping or clamping device having an actuator, having a drive that drives the actuator, and having at least two jaws that are coupled for movement in a movement direction with the actuator and that can be moved in movement direction toward and away from one another synchronously, the actuator comprising at least one spindle having at least two threaded portions, characterized in that a working portion that meshes with the threaded portion is arranged on the jaw side in each case for the movement coupling, and further having a drive pinion and a drive transmission, the drive transmission having first and second transmission elements being provided between the drive and the actuator, the first transmission element cooperating with the drive pinion and the second transmission element cooperating with a gearwheel arranged on the spindle, wherein the diameter of each threaded portion being greater than an extent of the associated working portion transverse to the movement direction of the jaw.

2. Gripping or clamping device according to claim 1, characterized in that the working portion is formed as a toothed rod portion.

3. Gripping or clamping device according to claim 1, characterized in that two jaws that are coupled in movement with the actuator are provided and in that the actuator comprises at least one spindle having two oppositely directed thread portions that each cooperate with one jaw.

4. Gripping or clamping device according to claim 1, characterized in that the drive comprises a motor having a drive shaft, the drive shaft and the actuator having axes of rotation that extend mutually parallel.

5. Gripping or clamping device according to claim 4, characterized in that the axes of rotation of the drive shaft and of the actuator extend parallel to the movement direction of the jaw.

6. Gripping or clamping device according to claim 1, characterized in that the axis of rotation of the transmission element extends parallel to the axis of rotation of the actuator.

7. Gripping or clamping device according to claim 1, characterized in that the working portion has an oblique toothing.

8. Gripping or clamping device according to claim 7, characterized in that the pitch angles of the threaded portion and of the oblique toothing are identical.

9. Gripping or clamping device according to claim 8, characterized in that the pitch angle is between 1° and 7°.

10. Gripping or clamping device according to claim 1, characterized in that the outer contour of the oblique toothing is formed complementary to the outer contour of the threaded portion.

11. Gripping or clamping device according to claim 1, characterized in that a resiliently yielding spring element is provided between the jaw and the working portion wherein the resiliently yielding spring is arranged in grooves that are defined by the jaws on one side and by toothed rod portions on the other side.

12. Gripping or clamping device according to claim 11, characterized in that the spring element extends in a groove that extends transverse to the movement direction of the jaw and that is defined by the jaw on one side and the working portion on the other side.

13. Gripping or clamping device according to claim 1, characterized in that the jaw is guided in a jaw guide of a base housing, the actuator being arranged below the jaw guide in the base housing.

14. Gripping or clamping device according to claim 13, characterized in that the drive, the actuator and the jaw guide are arranged substantially vertically above one another in the base housing.

15. Gripping or clamping device according to claim 1, characterized in that the working portion has a straight toothing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 is a longitudinal section through a parallel gripper;

(3) FIG. 2 is a section along the line II-II of FIG. 1;

(4) FIG. 3 is a section along the line of FIG. 1;

(5) FIG. 4 is an enlarged drawing of a detail of the drawing of FIG. 3;

(6) FIG. 5a is a side view of the parallel gripper of FIG. 1;

(7) FIG. 5b is a section along the line V-V of FIG. 5a;

(8) FIG. 5c is a section along the line V-V of FIG. 5a, showing a different variant of the working portion from FIG. 5b.

DETAILED DESCRIPTION

(9) FIGS. 1 to 3 show a gripping device 2 formed as a parallel gripper. This comprises a base housing 4 having a jaw guide 8 that extends in a longitudinal direction 6 for gripper jaws 10, 12 that are insertable into the jaw guide 8 in the longitudinal direction and displaceably mounted therein. The longitudinal direction 6 also corresponds to the displacement direction 6. Mounting openings, for detachably attaching gripping finger elements in the broadest possible sense, are provided on an upper face of the gripper jaws 10, 12, and will not be described further herein.

(10) As is clear from FIG. 2, the gripper jaws 10, 12 each comprise guide webs 13 extending in the displacement direction 6 on both sides, three guide webs 13, which are arranged above one another transverse to the displacement direction 6 and extend over the entire length of the gripper jaws 10, 12, being provided on both sides. As can further be seen from FIG. 2, the jaw guide 8 in the gripper housing 4 has guide grooves that are formed complementary to the guide webs 12 and in which the guide webs 13 can engage and slide in the displacement direction 6, the guide webs 13 engaging in the guide grooves 14 substantially without play.

(11) For displacing the jaws 10, 12, an actuator 16 is coupled in movement with the jaws 10, 12, the actuator 16 having a spindle 18 having two oppositely directed thread portions 20, 22, which can be seen particularly clearly in FIGS. 1 and 3. For the movement coupling, a toothed rod portion 24, 26 that meshes with the thread portion 20, 22 is arranged on the jaws 10, 12 on the jaw side in each case (cf. FIG. 1). By contrast with the prior art, there is direct movement coupling between the toothed rod portions 24, 26 arranged on the jaw side and the threaded portions 20, 22 of the spindle. A spindle nut that fully surrounds the spindle is entirely superfluous. The gripping device 2 can thus in particular be of a narrower construction. Further, this brings about a reduction in weight and a reduction in the complexity of production and assembly. Further, synchronous movement of the two jaws 10, 12 by means of the actuator 16 is made possible.

(12) As can be seen from FIG. 1, the actuator 16 is driven by a drive 27 that comprises an electric motor 28 and a drive shaft 30 having a gearwheel 32.

(13) As can be seen from FIG. 2, a drive transmission 34 formed as a spur wheel transmission is provided with two transmission elements 36, 38 between the drive 27 and the actuator 16. The first transmission element 36 cooperates with the drive pinion 32, whilst the second transmission element 38 cooperates with a gearwheel 40 arranged on the spindle 18.

(14) As can be seen from FIGS. 1 and 2, the axes of rotation 42, 44 of the drive shaft 30 and of the actuator 16 extend parallel to the movement direction 6 of the jaw. The axes of rotation 46, 48 of the transmission elements 36, 38 also extend parallel thereto. Further, the axes of rotation 42, 44, 48 of the drive shaft 30, of the actuator 16 and of the second transmission element 38 lie in a shared plane that forms a central longitudinal plane of the parallel gripper 2. Further, the drive 27, the actuator 16 and the jaw guide 8 are arranged vertically above one another.

(15) The electric motor 28 is controllable via a circuit board 52, the circuit board 52 being connected to the motor 28 via a wired connection 50. The circuit board 52 is positioned on the side of the motor 28 facing away from the drive shaft 30 in the displacement direction 6.

(16) As can be seen from FIGS. 5b and 5c, the diameter d of the threaded portion 20, 22 is greater than the extent e of the toothed rod portion 24, 26 transverse to the movement direction 6 of the jaws 10, 12, the actuator 16 being arranged below the jaw guide 8 in the base housing 4. As can be seen in particular from FIG. 1, the jaw guide 8 has an open lower face.

(17) In FIGS. 1, 3 and 4 it can further be seen that the threaded portion 20, 22 is formed as a screw having a plurality of screw threads, the pitch angle being approximately 3.5°. The toothed rod portions 24, 26 also have an inclined toothing having this same pitch angle.

(18) As can be seen from FIG. 1, the toothed rod portions 24, 26, each having two rods 54, 56 extending transverse to the displacement direction 6, are arranged on the jaws 10, 12, in such a way that the rods 54, 56 form a suspension for the toothed rod portions 24, 26.

(19) The toothed rod portions 24, 26 each have two mutually opposing narrow faces that extend transverse to the movement direction 6 of the jaws 10, 12. On each narrow face, as can be seen in FIG. 1, two spring elements 60, 62 are provided, between which, as seen in the movement direction 6 of the jaws 10, 12, a toothed rod portion 24, 26 is provided in each case. The spring elements 60, 62 are arranged in grooves that are defined by the jaws 10, 12 on one side and by the toothed rod portions 24, 26 on the other side. As can be seen from FIG. 1, the narrow faces of the toothed rod portions 24, 26 are spaced apart slightly from the jaws 10, 12.

(20) The spring elements 60, 62 are formed in particular as resilient elastomer blocks. In this case, the actuator can be fixed by a braking unit (not shown) in particular when the maximum deformation or at least almost the maximum deformation of the spring elements 60, 62 is reached. In addition, the self-inhibition between the toothed rod portions 24, 26 and the threaded portions 20, 22 may also be sufficient to fix the jaws, in such a way that no braking unit need be used. As a result, gripping force can be almost fully maintained, or a gripping force can be provided that is greater than a gripping force supplied purely by the drive 27.

(21) As a result of the actuator 16 comprising a spindle 18 having two oppositely directed thread portions 20, 22 that each cooperate with a jaw 10, 12, the jaws 10, 12 can be moved toward and away from one another synchronously.

(22) FIG. 5c shows a variant of the working portion 240. The working portion 240 is formed as a spindle nut portion that extends over a circumferential portion and that has straight toothing. As a result, an enlarged contact area between the threaded portion 20 and the working portion 240 is provided.

(23) Overall, with the invention a gripping or clamping device of a compact construction can be provided that is comparatively simple to manufacture and of comparatively low weight, the jaws 10, 12 being moved synchronously.