A composite multi-claw assembly

Abstract

The utility model relates to a kind of composite multi-paw assembly, including coaxial setting clamping sleeve, composite clamping mechanism and inner sleeve, the clamping sleeve with the inner sleeve is threadedly connected and is formed in inside and surrounds the accommodation cavity of composite clamping mechanism, the composite clamping mechanism is axially fixed between the clamping sleeve with the inner sleeve;The composite clamping mechanism includes elastic rubber tube and N clamping claws on the elastic rubber tube front end face around shaft, the elastic rubber tube has the shaft hole for rivet to enter, the central angle of the clamping claw is 360 ° / N, all clamping claws are made into the conical frustum structure that axially penetrates, N is the positive integer greater than or equal to 3, the inside of each clamping claw is equipped with anti-skid tooth, and the tail of each clamping claw is equipped with the embedded part that is tightly surrounded by the elastic rubber tube.The utility model can reduce wear, improve convenience and enhance clamping stability.

Description

Technical Field

[0001] This utility model relates to the field of riveting technology, and in particular to a composite multi-claw assembly. Background Technology

[0002] As a high-efficiency riveting tool, the core workflow of a rivet gun is "clamping → pulling → breaking," with the "clamping" action completed by the clamping mechanism. In existing technology, the rivet gun locking mechanism mainly consists of a chuck, a push rod, and a spring. The chuck, as the actuating component for the clamping action, is primarily a two-piece structure, with some employing a three-piece structure. It clamps the rivet through radial contraction. The push rod, through its inclined surface structure, changes the direction of force transmission, driving the chuck to radially open and hold the rivet in place. The spring provides the restoring force, driving the clamping mechanism to reset and release the chuck after the riveting action is complete. This structure has the following drawbacks: 1. Poor clamping stability: Two-piece jaws can only provide clamping force in two directions. The asymmetrical force makes the rivet slip easily, affecting the riveting accuracy; although three-piece jaws distribute the force more evenly, the problem of coordination and optimization with other components has not been solved. 2. Short component lifespan: The chucks are subjected to concentrated loads for a long time, resulting in severe wear; the springs are prone to fatigue failure under high-frequency and low-frequency use scenarios, requiring frequent replacement; moreover, it is impossible to make a quick and reasonable judgment on spring failure, leading to installation failure. 3. Poor ease of replacement: Whether it is a two-piece or traditional three-piece chuck, they are all independent components, making positioning difficult during installation and replacement cumbersome, which affects work efficiency.

[0003] Therefore, it is necessary to improve the locking mechanism of the rivet gun to solve the above problems. Utility Model Content

[0004] The main objective of this invention is to provide a composite multi-jaw assembly that can reduce wear, improve replacement convenience, and enhance clamping stability.

[0005] This utility model achieves the above-mentioned objective through the following technical solution: a composite multi-jaw assembly, comprising a clamping sleeve, a composite clamping mechanism, and an inner sleeve arranged coaxially, wherein the clamping sleeve is threadedly connected to the inner sleeve and forms a receiving cavity surrounding the composite clamping mechanism inside, and the composite clamping mechanism is axially fixed between the clamping sleeve and the inner sleeve; the composite clamping mechanism includes an elastic rubber tube and N jaws evenly distributed around the front end face of the elastic rubber tube, wherein the elastic rubber tube has a shaft hole for rivets to pass through, the central angle of the jaws is 360° / N, all jaws are assembled into an axially penetrating frustum structure, N is a positive integer greater than or equal to 3, each jaw has anti-slip teeth on its inner side, and each jaw has an embedding part tightly surrounded by the elastic rubber tube at its tail.

[0006] Specifically, there are three chucks, and the central angle of each of the three chucks is 120°.

[0007] Specifically, the hardness of the elastic rubber tube is Shore A 85-95 degrees.

[0008] Specifically, each jaw has a conical surface on its outer side, the clamping sleeve extends axially and has an inner conical surface that is thinner on the outside and thicker on the inside at the front of the receiving cavity, the rear outer circumference of the clamping sleeve has an internal thread, the inner sleeve includes an external thread portion, the external thread portion engages with the internal thread, and the inner conical surface generates a radial clamping force on the rivet by pressing the conical surface of the jaw.

[0009] Furthermore, the sleeve also includes a coarse shank located at the rear of the external thread portion, and when the inner sleeve is fully tightened with the clamping sleeve, the rear edge of the clamping sleeve abuts against the front surface of the coarse shank.

[0010] The beneficial effects of this utility model's technical solution are: 1. Multi-piece jaws optimize force distribution and reduce wear; elastic rubber tubes replace traditional springs to improve fatigue life in high-frequency use scenarios; adopting a lifespan design, when replacing jaws, the entire multi-jaw assembly is replaced to ensure the effectiveness of installation function; 2. Through the composite structure design, the chuck and the elastic drive component are integrated into a single unit, enabling quick installation and ensuring a one-step installation, thus avoiding installation failures caused by chuck misalignment and damage to the chuck; 3. By fixing multiple claws with elastic rubber tubes, precise positioning can be achieved. The symmetrical structure ensures that the rivet is subjected to uniform force, avoids slippage, and improves the success rate of riveting. Attached Figure Description

[0011] Figure 1 This is a perspective view of the composite multi-claw assembly in the embodiment; Figure 2 An exploded view of the composite multi-claw assembly in the embodiment; Figure 3 This is a cross-sectional view of the composite multi-claw assembly in the embodiment; Figure 4 This is an exploded view of the compound clamping mechanism.

[0012] The numbers in the image represent: 1-Clamping sleeve, 11-Receiving cavity, 12-Inner conical surface, 13-Internal thread; 2-Composite clamping mechanism, 21-Elastic rubber tube, 211-Shaft hole, 22-Claw, 221-Conical surface, 222-Anti-slip teeth, 223-Embedded part; 3-Inner sleeve, 31-External threaded part, 32-Rough shank part. Detailed Implementation

[0013] The present invention will be further described in detail below with reference to specific embodiments.

[0014] Example: like Figure 1 and Figure 2 As shown, a composite multi-jaw assembly of this utility model includes a clamping sleeve 1, a composite clamping mechanism 2, and an inner sleeve 3 arranged coaxially. The clamping sleeve 1 and the inner sleeve 3 are threadedly connected and form a receiving cavity 11 inside that surrounds the composite clamping mechanism 2. The composite clamping mechanism 2 is axially fixed between the clamping sleeve 1 and the inner sleeve 3.

[0015] Both the clamping sleeve 1 and the inner sleeve 3 are made of rigid materials. The material of the composite clamping mechanism 2 is elastic. The clamping sleeve 1 and the inner sleeve 3 can lock the composite clamping mechanism 2 in the receiving cavity 11 and use its local elasticity to clamp the rivet.

[0016] like Figure 3 and Figure 4 As shown, the composite clamping mechanism 2 includes an elastic rubber tube 21 and three jaws 22 evenly distributed around the front end face of the elastic rubber tube 21. The elastic rubber tube 21 has a shaft hole 211 for rivets to pass through. The central angle of the jaws 22 is 120°. The three jaws 22 are assembled into an axially continuous frustum structure. Each jaw 22 has a conical surface 221 on the outer side and anti-slip teeth 222 on the inner side. Each jaw 22 has an embedded part 223 tightly surrounded by the elastic rubber tube 21 at its tail.

[0017] The elastic rubber tube 21 is a thick-walled cylindrical elastic component, which can be made of polyurethane elastomer (PU) or nitrile rubber (NBR). The elastic rubber tube 21 replaces the traditional metal spring, avoiding fatigue fracture under high-frequency use and increasing service life by 3-5 times. The rubber material also has cushioning properties, reducing vibration and impact, ensuring both elastic return requirements and sufficient structural strength to transmit driving force. The jaws 22 are designed to have the same lifespan as the elastic rubber tube 21. When replacing the jaws, the entire multi-jaw assembly is replaced, ensuring the effectiveness of the installation function. The jaws 22 are made of rigid materials (such as high-strength wear-resistant alloy steel processed by heat treatment). All jaws 22 form a petal-shaped splicing structure, evenly distributed along the circumference, used to clamp rivets that partially penetrate the shaft hole 211, ensuring symmetrical force during clamping. The elastic rubber tube 21 is used to fix all jaws 22. Because the elastic rubber tube 21 has good elasticity, it allows each jaw 22 to move slightly inside the clamping sleeve 1. The number of jaws 22 is not limited to three, but can be N, where N is a positive integer greater than or equal to 3, and the central angle of each jaw 22 is 360° / N. This solves the rivet slippage problem caused by the asymmetrical force distribution of traditional two-piece jaws, while also distributing the load and reducing wear on a single jaw. The conical surface 221 can cooperate with the clamping sleeve 1 to generate radial clamping force. The anti-slip teeth 222 are used to contact the rivet. When the composite multi-jaw assembly tightens the rivet, they can engage with the rivet surface to transmit pull-out force, thus enabling it to complete the riveting smoothly. The insert 223 is the part that is embedded in the elastic rubber tube 21. As long as the outer end is slightly larger than the inner end, it can avoid detachment from the elastic rubber tube 21, so its structure is not necessarily limited to a spherical shape. The jaws 22 and the elastic rubber tube 21 are bonded or secondary injection molded into an integrated component. During installation, no separate positioning is required; they can be directly inserted into the gun head, improving replacement efficiency by more than 80%. The hardness of the elastic rubber tube 21 is set to Shore A 85-95 degrees, which takes into account both elastic recovery capability and structural strength, and ensures stable transmission of driving force.

[0018] like Figure 2 and Figure 3 As shown, the clamping sleeve 1 extends axially and has an inner conical surface 12 with a thinner outer surface and a thicker inner surface at the front of the receiving cavity 11. The outer circumference of the rear part of the clamping sleeve 1 is provided with an internal thread 13. The inner conical surface 12 generates a radial clamping force on the rivet by squeezing the conical surface 221 of the jaw 22.

[0019] like Figure 2 and Figure 3 As shown, the inner sleeve 3 includes an external threaded portion 31 and a coarse shank portion 32 located behind the external threaded portion 31. The external threaded portion 31 engages with the internal thread 13, thereby causing the front end face of the external threaded portion 31 to abut against the rear of the compound clamping mechanism 2. When the inner sleeve 3 and the clamping sleeve 1 are fully tightened, the rear edge of the clamping sleeve 1 abuts against the front surface of the coarse shank portion 32.

[0020] The working process of this composite multi-jaw assembly is as follows: 1. Clamping stage: After the rivet is inserted into the shaft hole 211, the inner sleeve 3 moves axially, and the three jaws 22 are driven to contract radially through the inner conical surface 12 of the inner sleeve 3, thus symmetrically clamping the rivet. 2. Pull-out stage: The anti-slip teeth 222 engage with the rivet surface, transmitting the pull-out force and completing the riveting; 3. Reset stage: After the riveting is completed, the inner sleeve 3 moves in the opposite direction, the elastic rubber tube 21 releases elastic potential energy, drives the claw 22 to radially open and reset, and loosens the rivet.

[0021] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A composite multi-claw assembly, characterized in that: The device includes a clamping sleeve, a composite clamping mechanism, and an inner sleeve arranged coaxially. The clamping sleeve is threadedly connected to the inner sleeve and forms a receiving cavity inside that surrounds the composite clamping mechanism. The composite clamping mechanism is axially fixed between the clamping sleeve and the inner sleeve. The composite clamping mechanism includes an elastic rubber tube and N claws evenly distributed around the front end face of the elastic rubber tube. The elastic rubber tube has a shaft hole for rivets to pass through. The central angle of the claws is 360° / N. All the claws are assembled into an axially continuous frustum-shaped structure. N is a positive integer greater than or equal to 3. Each claw has anti-slip teeth on its inner side and an embedding part tightly surrounded by the elastic rubber tube at its tail.

2. The composite multi-jaw assembly according to claim 1, characterized in that: The chuck has three claws, and the central angle of each claw is 120°.

3. The composite multi-jaw assembly according to claim 1, characterized in that: The hardness of the elastic rubber tube is Shore A 85-95 degrees.

4. The composite multi-jaw assembly according to claim 1, characterized in that: Each jaw has a conical surface on its outer side. The clamping sleeve extends axially and has an inner conical surface that is thinner on the outside and thicker on the inside at the front of the receiving cavity. The rear outer circumference of the clamping sleeve has an internal thread. The inner sleeve includes an external thread portion that mates with the internal thread. The inner conical surface generates a radial clamping force on the rivet by pressing the conical surface of the jaw.

5. The composite multi-jaw assembly according to claim 4, characterized in that: The sleeve also includes a coarse shank located at the rear of the external thread portion. When the inner sleeve is fully tightened with the clamping sleeve, the rear edge of the clamping sleeve abuts against the front surface of the coarse shank.

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