CN114474131B

CN114474131B - Clamping gripper

Info

Publication number: CN114474131B
Application number: CN202210108123.1A
Authority: CN
Inventors: 江励; 赖根; 汤健华
Original assignee: Wuyi University
Current assignee: Wuyi University
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2024-05-07
Anticipated expiration: 2042-01-28
Also published as: CN114474131A

Abstract

The invention discloses a clamping gripper, and relates to the field of manipulators. Wherein, the centre gripping tongs includes: a mounting base; a plurality of guide rails fixedly connected with the mounting seats; the clamping jaw comprises at least two clamping jaws, wherein each clamping jaw comprises a sliding piece, a connecting piece and a clamping assembly, one end of each sliding piece is in sliding connection with the guide rail, and the other end of each sliding piece is fixedly connected with the connecting piece; the clamping assembly comprises a plurality of cams and a plurality of rotating shafts, the plurality of rotating shafts are arranged at intervals along the length direction of the connecting piece, the plurality of cams are in one-to-one corresponding rotation connection with the rotating shafts, the cams comprise abutting parts protruding out of the connecting piece towards the clamping direction, and the distance from the end parts of the peripheral edges of the abutting parts to the rotating shafts is gradually increased along the upward direction; and the driving device is fixedly connected with the mounting seat or the guide rail. The cam arranged on the clamping jaw is protruded out of the connecting piece to be abutted with the clamped object so as to limit the position of the clamped object. When the clamping force is overlarge, the cam can rotate in the direction away from the clamped object, and the damage to the clamped object caused by overlarge clamping force can be reduced.

Description

Clamping gripper

Technical Field

The invention relates to the field of manipulators, in particular to a clamping gripper.

Background

In the production process of modern manufacturing industry, mechanical holders are widely used in automatic production lines to replace people to carry out large-scale and high-quality conveying work. In the related art, there is a clamping jaw which can be used for clamping and carrying objects, the clamping jaw comprises a connecting seat and two clamping arms, the two clamping arms are controlled to be close to or far away from each other, and the objects can be clamped or released. However, such jaws typically hold the object in rigid contact, with the holding force being improperly controlled, and the object being easily damaged.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, the invention provides the clamping handle which can reduce damage to the object in the process of clamping the object.

According to an embodiment of the present invention, a grip handle includes:

A mounting base;

The guide rails are fixedly connected with the mounting seats;

the clamping jaw comprises at least two clamping jaws, wherein each clamping jaw comprises a sliding piece, a connecting piece and a clamping assembly, one end of each sliding piece is in sliding connection with the corresponding guide rail, and the other end of each sliding piece is fixedly connected with the corresponding connecting piece; the clamping assembly comprises a plurality of cams and a plurality of rotating shafts, the plurality of rotating shafts are arranged at intervals along the length direction of the connecting piece, the plurality of cams are in one-to-one corresponding rotation connection with the rotating shafts, the cams comprise abutting parts protruding out of the connecting piece towards the clamping direction, and the distance from the end parts of the peripheral edges of the abutting parts to the rotating shafts is gradually increased along the upward direction;

The driving device is fixedly connected with the mounting seat or the guide rail and is used for driving at least two clamping jaws to mutually approach or separate along the linear direction.

The clamping gripper provided by the embodiment of the invention has at least the following beneficial effects:

In the clamping process, the driving device drives at least two clamping jaws to mutually approach along the extending direction of the guide rail so as to clamp an object. The abutting part of the cam abuts against the clamped object to limit the position of the clamped object. When the clamping force is overlarge, the cam can rotate in the direction away from the clamped object, so that the condition that the clamped object is damaged due to overlarge clamping force is reduced. The clamped object has a downward falling tendency under the action of gravity, and the cam can rotate towards the direction close to the clamped object under the action of friction force. The cam has a plurality of objects that can adapt to the centre gripping difference, improves the commonality and the stability of centre gripping tongs.

According to some embodiments of the invention, the clamping jaw comprises a torsion spring, the torsion spring is sleeved on the rotating shaft, and the torsion spring is used for resetting the cam.

According to some embodiments of the invention, the connecting piece is provided with a first limit groove, the cam is provided with a second limit groove, the torsion spring comprises a first radial arm and a second radial arm, the first radial arm is arranged in the first limit groove, and the second radial arm is arranged in the second limit groove.

According to some embodiments of the invention, the outer circumference of the abutment is provided in an involute shape along the contour line in which it is located.

According to some embodiments of the invention, the part of the cam protruding from the connecting piece is provided with a plurality of grooves, the grooves are arranged at intervals along the periphery of the cam, the cam further comprises an anti-slip piece, one part of the anti-slip piece is fixedly connected with the grooves, and the other part of the anti-slip piece protrudes from the grooves towards the clamping direction.

According to some embodiments of the invention, the groove comprises a first clamping groove and a second clamping groove, the first clamping groove is communicated with the second clamping groove, and an included angle a is formed between the lower bottom surface of the first clamping groove and the lower bottom surface of the second clamping groove, so that 0 ° < a <180 ° is satisfied.

According to some embodiments of the invention, the driving device comprises motors and screw rods, wherein the number of the motors corresponds to that of the clamping jaws, the motors are fixedly connected to the mounting seat, the output ends of the motors are fixedly connected to one end of the screw rods, and the screw rods are in threaded connection with the sliding piece.

According to some embodiments of the invention, the connecting piece comprises at least three connecting plates, at least three connecting plates are arranged at intervals along the width direction of the guide rail, and at least two groups of clamping assemblies are respectively arranged between adjacent connecting plates.

According to some embodiments of the invention, the cam portion extends outwards to form a first limiting part, the connecting piece is provided with a first limiting part, the first limiting part can be abutted with the first limiting part to limit the rotation angle of the cam in a first direction, the cam portion protrudes outwards to form a second limiting part, the connecting piece is provided with a second limiting part, the second limiting part can be abutted with the second limiting part to limit the rotation angle of the cam in a second direction, and the first direction is opposite to the second direction.

According to some embodiments of the invention, the mounting seat comprises a fastener, a guide member and a moving member, wherein the moving member is sleeved on the guide member, the moving member can move along the length direction of the guide member so as to adjust the whole length of the mounting seat, a plurality of connecting holes are formed in the length direction of the moving member and the guide member, and the fastener penetrates through the connecting holes so as to fix the relative positions of the moving member and the guide member.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention is further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a schematic view of the overall structure of a gripping grip provided by an embodiment of the present invention;

FIG. 2 is a schematic exploded view of a jaw according to one embodiment of the present invention;

FIG. 3 is an enlarged schematic view at A in FIG. 2;

FIG. 4 is an exploded view of a jaw from another perspective provided by one embodiment of the present invention;

FIG. 5 is a schematic illustration of a cam provided by an embodiment of the present invention;

Fig. 6 is a schematic view of a portion of a gripping handle according to an embodiment of the present invention.

Reference numerals:

A grip 1000;

mount 100, moving member 110, connecting hole 111, guide 120, and fastener 130;

a guide rail 200 and a limit structure 210;

Jaw 300, slider 310, nut 311, connector 320, connecting plate 321, first limit groove 3211, spindle 322, first limit 323, second limit 324, cam 330, first limit 331, second limit 332, second limit 333, tooth 334, abutment 335, groove 336, first slot 3361, second slot 3362, bearing 335, torsion spring 340, first radial arm 341, second radial arm 342;

a driving device 400, a motor 410 and a screw 420.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

In the description of the present invention, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present invention and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present invention can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.

Referring to fig. 1 and 2, a schematic diagram of a gripping gripper 1000 according to an embodiment of the present invention is shown. The clamping grip 1000 can be used in an automatic production line to replace a person to complete a large-scale and high-quality carrying work. In some cases, the gripping hand 1000 may have a holding force greater than the maximum pressure that the gripping object can bear due to improper control or abnormal conditions, while the gripping hand 1000 of the present invention can reduce damage to the object caused by excessive holding force, and can better protect the object being handled.

Referring to fig. 1 and 2, the grip handle 1000 includes a mounting base 100, a guide rail 200, a jaw 300, and a driving device 400. The mounting seat 100 is provided with a mounting position for mounting the guide rail 200 so that the guide rail 200 is fixedly connected with the mounting position, and the mounting position can be a threaded hole or an area which can facilitate welding of the guide rail 200. The mounting base 100 is provided with a plurality of mounting positions, so that the number of the clamping jaws 300 and the guide rails 200 can be increased according to actual requirements to replace different clamping modes. For example, three clamping jaws 300 can clamp a large round object with better stability than two modes.

Referring to fig. 2, there are at least two jaws 300 such that at least two jaws 300 cooperate to grip an object. The clamping jaw 300 comprises a sliding piece 310, a connecting piece 320 and a clamping assembly, one end of the sliding piece 310 is in sliding connection with the guide rail 200, and the other end of the sliding piece 310 is fixedly connected with the connecting piece 320 so as to drive the connecting piece 320 to move along the guide rail 200. The clamping assembly comprises a plurality of cams 330 and a plurality of rotating shafts 322, wherein the rotating shafts 322 are arranged at intervals along the length direction of the connecting piece 320, and the cams 330 are in one-to-one corresponding rotation connection with the rotating shafts 322. The cam 330 includes an abutting portion 335 protruding from the connector 320 in the clamping direction, and the abutting portion 335 abuts against the object during clamping of the object, so as to fix the position of the clamped object. The distance from the end of the abutment peripheral edge to the rotation shaft gradually increases in the upward direction. The cam 330 has a plurality of functions to accommodate different objects to be clamped, thereby improving versatility and stability of clamping the grip 1000.

The gripping direction refers to the moving direction of the gripping jaw 300 when gripping an object. It should be noted that, the rotating shaft 322 may be a bolt, or may be a structure formed by protruding the connecting piece 320 outwards. For example, in some embodiments, when the bolt is used as the rotating shaft 322 of the cam 330 and the connecting member 320 includes a plurality of connecting plates 321, the bolt can serve to connect the plurality of connecting plates 321 in addition to the rotating shaft 322 of the cam 330, thereby improving the utilization rate of the bolt.

Referring to fig. 1, the driving device 400 is disposed at a mounting position of the mounting base 100 and is fixedly connected to the mounting base 100. The driving device 400 is used to drive at least two clamping jaws 300 towards or away from each other to clamp or release an object. It should be noted that the driving device 400 may also be fixedly connected to the guide rail 200, and an appropriate scheme is selected according to practical situations, and the present invention is not particularly limited herein.

It can be appreciated that, in the process of clamping an object, the driving device 400 drives the clamping jaws 300 to approach each other, the abutting portion 335 of the cam 330 contacts the object to be clamped first, when the clamping force gradually increases, the cam 330 rotates in a direction away from the object to be clamped, so as to achieve the buffering effect and reduce the damage to the clamped object caused by the excessive clamping force. The clamped object tends to drop downwards, and the cam 330 rotates in a direction approaching the clamped object under the action of friction force, and the distance from the end of the peripheral edge of the abutting part 335 to the rotating shaft gradually increases, so that the cam 330 can be self-locked to clamp the object.

In some embodiments, as described with reference to fig. 2, 3 and 5, the clamping jaw 300 further includes a torsion spring 340, where the torsion spring 340 is sleeved on the rotating shaft 322, and the torsion spring 340 can buffer and reset the cam 330. Resetting refers to the position in which the torsion spring 340 drives the cam 330 to a non-gripping position. It can be appreciated that when the holding force is greater than the elastic force of the torsion spring 340 during holding an object, the cam 330 can rotate away from the object to be held against the elastic force of the torsion spring 340, so that damage to the object to be held due to excessive holding force can be reduced. When the clamped object is released, the cam 330 can be reset to the position when the clamped object is not clamped under the elastic force of the torsion spring 340.

In some embodiments, referring to fig. 3 and 5, the connector 320 is provided with a first limiting groove 3211, the cam 330 is provided with a second limiting groove 333, the torsion spring 340 includes a first radial arm 341 and a second radial arm 342, the first radial arm 341 is disposed in the first limiting groove 3211, and the second radial arm 342 is disposed in the second limiting groove 333. The first limiting groove 3211 and the second limiting groove 333 are used for limiting the position of the torsion spring 340, preventing the torsion spring 340 from separating, improving the reliability of the clamping grip 1000, and simultaneously, in the rotation process of the cam 330, the first radial arm 341 can be elastically deformed by abutting against the wall surface of the first limiting groove 3211, and the second radial arm 342 can be elastically deformed by abutting against the wall surface of the second limiting groove 333, so as to limit the position of the cam 330. It should be noted that, the limiting torsion spring 340 may also be provided with limiting protrusions at both the connecting member 320 and the cam 330, and both ends of the torsion spring 340 respectively abut against the limiting protrusions, which may also play a role in limiting the position of the torsion spring 340.

In some embodiments, referring to fig. 5, the cam 330 includes an abutting portion 335, the abutting portion 335 protrudes from the connector 320, and an outer periphery of the abutting portion 335 is disposed along a contour line of the connecting portion and extends upwards. Wherein the involute is a base circle involute of the rotation center of the cam 330. As can be appreciated, the beneficial effect of the peripheral edge of the abutment 335 being an involute is as follows:

Since the cam 330 can rotate under the abutment of the clamped object, in order to ensure that a part of the cam 330 can always abut against the clamped object during rotation, the outer circumferential edge of the abutting part 335 is arc-shaped, so that the abutting of a part of side wall with the clamped object can be kept to limit the position of the clamped object, and the loosening condition of the clamped object is reduced.

In the clamping process, the clamped object has a downward falling trend, so that the cam 330 can be given a rotating force in a direction close to the clamped object, and the distance from a point to the circle center along the extending direction of the involute is gradually increased, so that the cam 330 can rotate in a direction close to the clamped object to clamp the clamped object when the clamped object has a falling trend, thereby self-locking is achieved, and the falling risk of the clamped object is reduced.

Because the normal line of any point on the involute is always tangent to the base circle, when the clamped object is abutted to the abutting part 335, a component force can always be tangent to the base circle at the abutting part, and when the component force is large, the cam 330 can be driven to rotate, the situation that the cam 330 is not rotated due to the fact that the resultant force crosses the center of a circle is avoided, and the situation that the clamped object is damaged can be reduced.

In order to reduce the risk of dropping the object during gripping of the object, it is necessary to provide an anti-slip structure on the cam 330. With continued reference to fig. 5, in some embodiments, the portion of the cam 330 protruding from the connector 320 includes a plurality of teeth 334, the plurality of teeth 334 being spaced along the circumference of the cam 330, with grooves 336 formed between adjacent teeth 334. Cam 330 also includes an anti-slip member (not shown) disposed partially within recess 336 and partially protruding from recess 336 in the clamping direction. It will be appreciated that in some embodiments, the anti-slip member may be initially a liquid silicone or rubber, for example, by pouring the liquid silicone into the grooves 336 formed by adjacent teeth 334, waiting for it to solidify to form an anti-slip member that wraps around a portion of cam 330. Thus, the groove 336 primarily functions as a fixed cleat. The antiskid piece adopts silica gel to make, and silica gel can increase the frictional force between cam 330 and the quilt clamp thing, and silica gel nature is soft simultaneously, has elasticity, and the quilt clamp thing of protection that can be better reduces its surface damage.

Referring to fig. 5, the groove 336 includes a first card slot 3361 and a second card slot 3362, the first card slot 3361 communicates with the second card slot 3362, and an angle a between a lower bottom surface of the first card slot 3361 and a lower bottom surface of the second card slot 3362 satisfies 0 ° < a <180 °. It can be appreciated that the first slot 3361 and the second slot 3362 can further improve the anti-falling effect and reduce the falling of the anti-sliding member. In some embodiments, the width of the second slot 3362 on the side far from the rotation center is smaller than the width of the second slot 3362 on the side near the rotation center, so as to further reduce the falling-off situation of the anti-slip member.

Referring to fig. 6, in some embodiments, the driving apparatus 400 includes a motor 410 and a screw 420, and the number of motors 410 and screws 420 is the same as the number of jaws 300. Wherein, the motor 410 is fixedly connected to the mounting base 100, the output end of the motor 410 is fixedly connected to one end of the screw 420 to drive the screw 420 to rotate, the screw 420 is in threaded connection with the slider 310, when the screw 420 rotates, the slider 310 can be driven to slide along the guide rail 200, the screw 420 is in threaded connection with the slider 310, the rotational movement can be changed into linear movement, and the motor 410 is used for driving the clamping jaws 300 to approach or separate from each other. The screw 420 may be directly screwed to the slider 310, or the slider 310 may include the nut 311, and the screw 420 may be screwed to the nut 311. It should be further noted that, the motor 410 may be replaced by a hydraulic cylinder or an air cylinder, and an appropriate scheme is selected according to practical situations.

It will be appreciated that the clamping jaw 300 is clamped in a linear drive manner, taking into account that the screw 420 may be self-locking in some circumstances. For example, a self-locking screw 420 is required, the helix angle of which should be smaller than the friction angle of the screw pair material, i.e. the tangent of the helix angle is smaller than the friction coefficient. In the process of clamping and carrying objects, the clamping jaw 300 has a tendency of being propped open towards two sides by the clamped objects, so that the clamping jaw 300 is limited to be propped open by the self-locking screw, the driving pressure of the motor 410 is reduced, and the requirement on the motor 410 is further reduced.

Referring to fig. 1 and 2, in some embodiments, the connector 320 includes at least three connection plates 321, at least three connection plates 321 are disposed at intervals along the width direction of the guide rail 200, and at least two clamping assemblies are disposed between adjacent connection plates 321. For example, the connecting piece 320 includes three connecting plates 321, two clamping assemblies are arranged, two gaps are formed when the three connecting plates 321 are arranged at intervals, and the two clamping assemblies are respectively arranged between the two gaps and connected with the connecting plates 321. It can be appreciated that the arrangement of multiple groups of clamping assemblies can improve the stability of clamping and reduce the loosening phenomenon of the clamped objects.

Referring to fig. 2,3 and 5, the cam 330 is partially extended outwards to form a first limiting part 331, and the connector 320 is provided with a first limiting part 323, so that the first limiting part 331 can abut against the first limiting part 323 to limit the rotation angle of the cam 330 in the first direction and prevent the cam 330 from rotating excessively after the cam 330 is extruded by an object in the process of clamping the object. In other embodiments, the cam 330 is partially protruded outwards to form a second limiting part 332, and the connecting piece 320 is provided with a second limiting part 324, and after the object is released, the second limiting part 332 can abut against the second limiting part 324 to limit the rotation angle of the cam 330 in the second direction, so that the safety is improved. It should be noted that, the first direction is opposite to the second direction, and the first limiting member 323 and the second limiting member 324 may be welded on the connecting member 320 or formed by bolts.

Referring to fig. 5, in some embodiments, the outer circumferential edge of the first limiting portion 331 is a circular arc. It can be appreciated that the first limiting portion 331 may also abut against the clamped object when clamping some objects, so as to limit the position of the clamped object.

Referring to fig. 1, both ends of the guide rail 200 are provided with a limiting structure 210, and the limiting structure 210 may be plate-shaped, strip-shaped, or protruding structures. The limiting structure 210 is used for limiting displacement of the clamping jaw 300, preventing the clamping jaw 300 from being separated from the guide rail 200, and improving safety. In other embodiments, the limit structure 210 may also be a limit sensor, which can send a signal to control the driving device 400 to stop driving when the clamping jaw 300 is out of the stroke, and also indicate the over stroke.

Referring to fig. 2 and 4, the cam 330 is provided with a mounting hole, the clamping assembly includes a bearing 335, and the bearing 335 is disposed in the mounting hole and sleeved on the rotating shaft 322, so that the cam 330 can be rotatably connected to the rotating shaft 322. It can be appreciated that the bearing 335 is used to reduce the friction coefficient between the cam 330 and the rotating shaft 322, improve the rotation precision, prevent the cam 330 from seizing and lose the buffering effect.

Referring to fig. 2 and 4, in some embodiments, the mounting base 100 includes a guide 120 and a moving member 110, and the moving member 110 is sleeved on the guide 120, where the moving member 110 can move along the length direction of the guide 120 to adjust the overall length of the mounting base 100 to adapt to different working requirements. In other embodiments, the guide member 120 and the moving member 110 are provided with a plurality of connecting holes 111, the connecting holes 111 are arranged at intervals along the length direction of the guide member 120 and the moving member 110, and after the position between the moving member 110 and the guide member 120 is adjusted, the position between the moving member 110 and the guide member 120 can be fixed by penetrating the connecting holes 111 through the fastener 130. The position between the moving member 110 and the guide member 120 can be adjusted to accommodate different clamping requirements.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present invention.

Claims

1. A gripping gripper, comprising:

A mounting base;

The guide rails are fixedly connected with the mounting seats;

The driving device is fixedly connected with the mounting seat or the guide rail and is used for driving at least two clamping jaws to mutually approach or separate along the linear direction;

The cam part outwards extends to form a first limiting part, the connecting piece is provided with a first limiting part, the first limiting part can be abutted with the first limiting part to limit the rotation angle of the cam in the first direction, the cam part outwards protrudes to form a second limiting part, the connecting piece is provided with a second limiting part, the second limiting part can be abutted with the second limiting part to limit the rotation angle of the cam in the second direction, and the first direction is opposite to the second direction.

2. The grip of claim 1, wherein the jaws include torsion springs that are nested about the shaft and that are used to reset the cam.

3. The grip of claim 2, where the connector is provided with a first limit slot, the cam is provided with a second limit slot, the torsion spring includes a first radial arm and a second radial arm, the first radial arm is disposed in the first limit slot, and the second radial arm is disposed in the second limit slot.

4. The grip of claim 1, wherein the outer circumference of the abutment is involute along the contour line in which it is located.

5. The grip of claim 1, wherein the portion of the cam protruding from the connector is provided with a plurality of grooves spaced along the periphery of the cam, the cam further comprising an anti-slip member, a portion of the anti-slip member being fixedly connected to the grooves, and another portion of the anti-slip member protruding from the grooves in the grip direction.

6. The grip of claim 5, wherein the recess includes a first slot and a second slot, the first slot being in communication with the second slot, a lower bottom surface of the first slot forming an angle a with a lower bottom surface of the second slot, satisfying 0 ° < a <180 °.

7. The grip of claim 1, wherein the drive means includes motors and screws corresponding to the number of the jaws, the motors being fixedly coupled to the mounting base, the output ends of the motors being fixedly coupled to one end of the screws, the screws being threadably coupled to the slide.

8. The clamping grip of claim 1, wherein the connector includes at least three connector plates spaced apart along the width of the rail, and at least two sets of clamping assemblies are disposed between adjacent connector plates.

9. The grip of claim 1, wherein the mounting block includes a fastener, a guide member, and a moving member, the moving member is sleeved on the guide member, the moving member is movable along a length direction of the guide member to adjust an overall length of the mounting block, the moving member and the guide member are each provided with a plurality of connection holes along the length direction, and the fastener is inserted through the connection holes to fix a relative position of the moving member and the guide member.