Pneumatic hydraulic core-pulling riveting gun

Abstract

The invention relates to the technical field of riveting, in particular to a pneumatic hydraulic core-pulling riveting gun. The pneumatic hydraulic core-pulling riveting gun comprises a gun body, the gun body comprises an oil tank, a pressure cylinder communicated with the oil tank and a pull head assembly, the pull head assembly comprises an outer cylinder body connected with the oil tank, an inner cylinder body is movably installed in the outer cylinder body, a tension piston is installed in the inner cylinder body, and a piston cavity in the front side of the tension piston is communicated with the pressure cylinder. A thrust piston is installed at the rear end of the outer cylinder body, a tension piston communicating hole penetrating front and back is formed in the tension piston, a self-sealing connector is installed on the tension piston, a matched connector is installed on the thrust piston and comprises an ejector rod used for triggering the self-sealing connector, and a communicating channel leading to the rear side of the thrust piston is formed in the ejector rod. The front end of the push rod is provided with a sealing structure in sealing compression joint with the self-sealing joint. According to the pneumatic hydraulic core-pulling riveting gun, pushing force for pushing the locking ring can be provided while pulling force for pulling rivets is provided, and the requirement for riveting aviation rivets can be met.

Description

Technical Field

[0001] The invention relates to the technical field of riveting machines, in particular to a pneumatic hydraulic core-pulling rivet gun. Background Art

[0002] Blind rivets are widely used in aviation, aerospace, automobiles, ships and other fields. When using blind rivets, a rivet gun is usually required to complete the riveting. The shell of a commonly used rivet gun is usually a plastic shell. When facing harsh environments such as the aerospace field, the plastic shell is prone to deformation and aging, and is prone to oil and gas leakage, resulting in reduced pulling force, which can easily cause problems such as slow rivet pulling speed and incomplete rivet forming.

[0003] A Chinese invention patent application with application publication number CN118905143A and application publication date November 8, 2024 discloses a rivet gun, which includes a gun body and a pulling head assembly. The gun body includes a cylinder, a booster cylinder and a reversing structure. A button is also provided on the gun body. A booster piston is provided in the booster cylinder, and a cylinder piston is provided in the cylinder. The booster piston and the cylinder piston are fixedly connected by a piston rod. The area of ​​the cylinder piston is larger than the area of ​​the booster piston to form a boost ratio. The pulling head assembly includes a pulling head housing, and a piston shaft for pulling rivets is provided inside the pulling head housing. The piston shaft provides pulling force for pulling rivets under the action of hydraulic pressure. At the same time, the outer shell of the rivet gun is an aluminum alloy housing, which can better cope with harsh working environments. In the aerospace field, aviation rivets are widely used. The structure of aviation rivets is different from that of ordinary blind rivets. Ordinary blind rivets usually include a mandrel, a nut and a shell, while aviation rivets also have a locking ring. When riveting aviation rivets, the locking ring needs to be pushed out to cooperate with the shell and the nut to lock the workpiece. Therefore, when riveting, in addition to the pulling force of the rivet, a pushing force of the locking ring is also required. The above-mentioned rivet gun can only provide the pulling force of the rivet, which is not suitable for riveting aviation rivets. Summary of the invention

[0004] The purpose of the present invention is to provide a pneumatic hydraulic core-pulling rivet gun to solve the problem that the existing rivet gun cannot provide the thrust of the push lock ring required for riveting aviation rivets.

[0005] A pneumatic hydraulic core-pulling rivet gun comprises a gun body, which comprises an oil tank, a booster cylinder connected to the oil tank, and a pulling head assembly. The pulling head assembly comprises an outer cylinder body connected to the oil tank, an inner cylinder body movably installed in the outer cylinder body, a tension piston is installed at the front end of the inner cylinder body, the piston chamber on the front side of the tension piston is connected to the booster cylinder, a thrust piston fixedly connected to the inner cylinder body is installed at the rear end of the outer cylinder body, a tension piston communicating hole which passes through the tension piston from front to back is provided on the tension piston, a self-sealing joint is installed in the tension piston communicating hole, a mating joint matching the self-sealing joint is installed on the thrust piston, the mating joint comprises a push rod for triggering the self-sealing joint, a connecting channel leading to the rear side of the thrust piston is provided in the push rod, and a sealing structure which is sealed and crimped with the self-sealing joint is provided at the front end of the push rod.

[0006] Furthermore, a return spring is mounted between the rear side of the tension piston and the inner cylinder body.

[0007] Furthermore, the sealing structure at the front end of the push rod is a tapered through hole, and the through hole is sealed with the self-sealing joint.

[0008] Furthermore, the self-sealing joint includes a rod seat and a plug rod installed in the rod seat, the plug rod and the rod seat are clearance-matched, a liquid flow channel is provided in the plug rod, a plug rod connecting hole connected to the liquid flow channel is provided on the outer wall of the plug rod, and the rod seat and the rear end of the plug rod are sealed by a sealing ring.

[0009] Furthermore, the rear end of the plug rod is provided with a conical end for sealingly cooperating with the ejector rod.

[0010] Furthermore, a hollow shift adjustment shaft is arranged in the mating joint, a connecting hole is opened on the shift adjustment shaft and is connected with the connecting channel, and an adjusting bolt, an adjusting knob and an adjusting indicator ring are arranged at the rear end of the outer cylinder body.

[0011] Furthermore, a reversing mechanism and a cylinder are also provided in the gun body, and the reversing mechanism is communicated with the cylinder.

[0012] Furthermore, a cylinder piston is provided in the cylinder, a booster piston is provided in the booster cylinder, and the booster piston and the cylinder piston are fixedly connected via a piston rod.

[0013] Furthermore, a gas-liquid isolation ring is provided between the piston rod and the booster cylinder.

[0014] Furthermore, a connecting head is provided on the boosting piston, and the piston rod and the connecting head are connected via threads.

[0015] Beneficial effects: The pneumatic hydraulic core-pulling rivet gun of the present invention is an improved invention. The hydraulic oil in the pneumatic hydraulic core-pulling rivet gun of the present invention enters the piston cavity on the front side of the tension piston through the oil circuit. The tension piston moves backward under the action of the hydraulic pressure to provide the required tension for the pull rivet. The self-sealing joint provided on the tension piston cooperates with the matching joint on the thrust piston to make the hydraulic oil on the front side of the tension piston flow into the cavity on the rear side of the thrust piston. The inner cylinder moves forward under the action of the hydraulic oil to provide the aviation rivet with the thrust required for pushing the lock ring during riveting. The aviation rivet completes riveting under the tension provided by the tension piston and the thrust provided by the inner cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the gun body structure of an embodiment of a pneumatic hydraulic blind rivet gun of the present invention; Figure 2 The pneumatic hydraulic core-pulling rivet gun of the present invention Figure 1 A cross-sectional view of the reversing mechanism of the embodiment along the line AA; Figure 3 It is a schematic diagram of the gun head structure of the pneumatic hydraulic blind rivet gun of the present invention; Figure 4 The present invention is a schematic diagram of the assembly of the gun head and the gun head of the pneumatic hydraulic blind rivet gun.

[0017] In the figure: 1, gun body; 2, cylinder; 3, cylinder piston; 4, booster cylinder; 5, booster piston; 6, piston rod; 7, anti-loosening nut; 8, cylinder lower end cover; 9, base ring; 10, outer cylinder body; 11, front end cover; 12, rear end cover; 13, inner cylinder body; 14, thrust shaft; 15, thrust piston; 16, tension piston; 17, rod seat; 18, plug rod; 19, return spring; 20, gun head adapter; 21, push rod; 22, shift adjustment shaft; 23, adjustment bolt; 24, adjustment knob; 25, adjustment indicator ring; 26, indexing washer; 27, limit retaining spring; 28, feed Air head; 29, reversing valve body; 30, reversing valve core; 31, valve core filter; 32, reversing return spring; 33, reversing control rod; 34, valve core limit plug; 35, exhaust filter; 36, housing; 37, thrust sleeve; 38, anvil; 39, anvil connecting sleeve; 40, plunger housing; 41, tail seat; 42, buffer spring; 43, plunger; 44, jaw clamp; 45, pull head fixing ring; 46, limit pin; 47, gas-liquid isolation ring; 48, connector; 49, button valve core; 50, button valve seat; 51, limit retaining ring; 52, support ring; 53, plunger spring. DETAILED DESCRIPTION

[0018] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0019] The pneumatic hydraulic core-pulling rivet gun of the present invention is provided with an inner cylinder body and a self-sealing joint in the pulling head assembly of the gun body, and the hydraulic oil on the front side of the inner cylinder body flows into the cavity on the rear side of the inner cylinder body through the self-sealing joint and the matching mating joint. The inner cylinder body moves forward under the action of the hydraulic oil to provide the thrust required for pushing the locking ring of the aviation rivet during riveting, thereby meeting the requirement of the aviation rivet to push the locking ring out of the workpiece for locking during riveting.

[0020] In a basic embodiment, Figure 1 As shown, a cylinder 2 is arranged below the gun body 1, a cylinder piston is arranged in the cylinder 2, a booster cylinder 4 is arranged at the position of the handle of the gun body 1, the booster cylinder 4 is connected to the oil tank, a booster piston 5 is arranged in the booster cylinder 4, the booster piston 5 and the cylinder piston are fixedly connected by a piston rod 6, a locking nut 7 is installed at the connection between the lower end of the piston rod 6 and the cylinder piston, a cylinder lower end cover 8 is installed at the bottom of the cylinder 2, and a base ring 9 is installed below the cylinder lower end cover 8. The pulling head assembly is arranged at the upper end of the gun body 1, and the left and right sides of the outer cylinder body 10 are respectively provided with a front cover 11 and a rear cover 12, an inner cylinder body 13 is installed in the outer cylinder body 10, the left side of the inner cylinder body 13 is connected with a thrust shaft 14, and the right side of the inner cylinder body 13 is installed with a thrust piston 15, and a pulling piston 16 is installed inside the inner cylinder body 13, and the piston cavity on the front side of the pulling piston 16 is connected with the boosting cylinder 4, a middle through hole is opened on the pulling piston 16, and a self-sealing joint is arranged in the through hole, and a mating joint matching the self-sealing joint is arranged on the thrust piston 15, and a push rod 21 is arranged on the mating joint, and a sealing structure that can be sealed with the self-sealing joint is arranged at the front end of the push rod 21, and the self-sealing joint cooperates with the mating joint to make the hydraulic oil on the front side of the pulling piston flow into the rear side of the thrust piston 15, so that the inner cylinder body 13 can move forward under the action of the hydraulic oil. A limit pin 46 is provided between the front end cover and the inner cylinder body 13, and one end of the limit pin 46 is inserted into the inner cylinder body 13 to limit the displacement of the inner cylinder body 13 and the thrust shaft 14. A gun head adapter 20 is provided at the front end of the tension piston 16, and the gun head adapter 20 is fixedly connected to the tension piston 16. The gun head installed on the gun head adapter 20 can increase the pulling force required for the rivet under the action of the tension piston 16, and is suitable for installing aviation rivets of almost all diameters; in other embodiments, the corresponding gun head adapter 20 can be replaced according to the gun head used, and the pulling head assembly on the gun body 1 can be used to install other types of rivets.

[0021] In a preferred embodiment, a reset spring 19 is provided between the tension piston 16 and the inner cylinder body 13, and the tension piston 16 and the inner cylinder body 13 can be reset under the action of the reset spring 19 after riveting is completed; in other embodiments, a hydraulic channel can be provided in the inner cylinder body to reset the tension piston and the inner cylinder body under the action of hydraulic oil, and after the reset is completed, the hydraulic oil can return to the oil tank along the original path.

[0022] In a preferred embodiment, the sealing structure at the front end of the push rod 21 is a conical through hole, the conical surface of the through hole can be sealed with the plug rod 18, a liquid flow channel is provided in the plug rod 18, and a plug rod connecting hole connected to the liquid flow channel is also provided on the outer wall of the plug rod 18. The plug rod 18 and the rod seat 17 are clearance-matched to ensure that when the plug rod 18 is pushed open, the hydraulic oil can flow from the plug rod connecting hole into the liquid flow channel; a sealing ring is provided between the rear end of the plug rod 18 and the rod seat 17, so that the hydraulic oil can only flow to the rear side of the thrust piston through the liquid flow channel in the plug rod 18, which can To prevent the hydraulic oil from leaking from the contact surface between the rod seat 17 and the push rod 21 and filling the inner cylinder body, making the rivet gun unusable, the hydraulic oil on the front side of the tension piston can enter the mating joint through the liquid flow channel in the plug rod 18, and then flow into the rear side of the thrust piston 15, pushing the thrust piston and the inner cylinder body forward; in other embodiments, the rear end face of the rod seat 17 can be sealed with the front end face of the push rod, so that the hydraulic oil flows into the rear side of the thrust piston through the plug rod 18 and the gap between the plug rod and the rod seat 17, pushing the thrust piston and the inner cylinder body forward.

[0023] In a preferred embodiment, the push rod 21 can be used to limit the tension piston 16 and trigger the self-sealing joint composed of the plug rod and the rod seat. A hollow shift adjustment shaft 22 is installed in the push rod 21 of the mating joint. A connecting hole is opened on the shift adjustment shaft 22 to communicate with the connecting channel in the push rod 21. The hydraulic oil at the front end of the tension piston 16 can flow into the cylinder body on the rear side of the thrust piston 15 through the shift adjustment shaft 22. An adjusting bolt 23 is provided on the rear end cover 12, and a dividing washer 26 is installed between the rear end cover 12 and the adjusting bolt 23. An adjusting knob 24, an adjusting indicator ring 25 and a limiting retaining spring 27 are provided on the outside of the rear end cover 12. The gear position of the pull head assembly can be adjusted by cooperating between the shift adjustment shaft 22, the adjusting bolt 23 and the adjusting knob 24, and the corresponding riveting speed can be adjusted according to different gears of different rivets. In other embodiments, only a mating joint can be provided in the pull head assembly, and the hydraulic oil only flows into the closed cavity surrounded by the thrust piston and the outer cylinder body through the push rod, which does not affect the performance of the rivet gun.

[0024] In a preferred embodiment, a reversing mechanism is provided on the right side of the cylinder 2, and the reversing mechanism is connected to the cylinder 2. Figure 2As shown, the reversing mechanism is connected to an air inlet head 28, and the reversing mechanism includes a reversing valve body 29, a reversing valve core 30 is arranged in the reversing valve body 29, a reversing return spring 32 is arranged between the reversing valve core 30 and the reversing valve body 29, a valve core filter 31 is arranged at the lower end of the reversing valve core 30, a reversing control rod 33 and a valve core limit plug 34 are also arranged at the lower end of the reversing valve body 29, and an exhaust filter 35 is also installed at the lower end of the valve core limit plug 34 to filter the gas entering the cylinder 2; in other embodiments, the air inlet head 28 can adopt a rotating air inlet head 28 with adjustable angle, and the angle of the air inlet head 28 can be adjusted according to the specific usage conditions to facilitate the use of the rivet gun.

[0025] In a preferred embodiment, a connector 48 is provided below the booster piston 5, and the piston rod 6 is connected to the connector 48 by a thread, so that when it is necessary to inject hydraulic oil into the booster cylinder 4 of the rivet gun, the piston rod 6 can be easily installed and disassembled, and the operation is convenient. At the same time, a limiting retaining ring 51 is provided between the piston rod 6 and the booster piston 5 to prevent the piston rod 6 from wearing the booster piston 5. At the same time, a support ring 52 is provided at the connection between the upper end of the cylinder piston and the piston rod, which supports and guides the piston rod and prevents the piston rod from tilting. In other embodiments, the piston rod 6 and the booster piston 5 can be an integrated structure, which does not affect the overall performance of the rivet gun and the pulling force and thrust provided to the rivet during riveting.

[0026] A gas-liquid isolation ring 47 is also provided at the lower end of the booster cylinder 4. The sliding seal between the gas-liquid isolation ring 47 and the piston rod 6 can prevent the cylinder 2 from being connected to the booster cylinder 4, and prevent the hydraulic oil from flowing into the cylinder 2, resulting in a reduction of the hydraulic oil in the booster cylinder 4, thereby causing insufficient pulling force during riveting, thereby affecting the riveting quality; in other embodiments, multiple gas-liquid isolation rings 47 can be set between the booster cylinder 4 and the piston rod 6 to further improve the sealing effect between the cylinder 2 and the booster cylinder 4.

[0027] A button assembly is also provided on the gun body 1, and the button assembly includes a button valve core 49 and a button valve seat 50. The button assembly cooperates with the reversing mechanism in the gun body 1 to realize the up and down movement of the cylinder piston and the booster piston 5, thereby driving the pull head assembly to complete the riveting of the rivet.

[0028] like Figure 3As shown, the rivet gun of the present invention also includes a gun head, which includes a shell 36. When in use, the shell 36 of the gun head has one end of a mounting structure installed in the pull head assembly. A thrust sleeve 37 is arranged in the shell 36 of the gun head. The thrust sleeve 37 cooperates with the thrust shaft 14 in the pull head assembly. An anvil 38 and an anvil connecting sleeve 39 are arranged in the thrust sleeve 37. A plunger housing 40 is arranged in the anvil connecting sleeve 39. A tailstock 41 is fixedly connected to the left side of the plunger housing 40. The tailstock 41 cooperates with the gun head adapter 20 in the pull head assembly. The left end of the tailstock 41 is provided with a buffer spring 42, a plunger 43 is installed in the plunger housing 40, the right end of the plunger 43 extends out of the plunger housing 40, a plunger spring 53 is provided between the tailstock 41 and the plunger 43, a jaw clamp 44 is provided between the plunger housing 40 and the anvil 38, the jaw clamp 44 can be used to clamp the core of the blind rivet, the right end of the plunger 43 extends into the cavity surrounded by the jaw clamp 44, the plunger spring can tighten the rivet during riveting, and after the riveting is completed, the plunger can push out the discarded core rod under the action of the plunger spring. Figure 4 As shown, a pull head fixing ring 45 is provided on the outer side of the front end cover, and the pull head fixing ring 45 is connected to the front end cover by threads. A spring is provided between the pull head fixing ring 45 and the front end cover, and the gun head can be fixed by the pull head fixing ring 45 when the gun head is installed on the gun body 1; in other embodiments, corresponding threads can be provided on the gun head and the gun head adapter 20, and the gun head can be directly connected to the gun body 1 by threads.

[0029] The working principle of the pneumatic hydraulic core-pulling rivet gun of the present invention is: Install the gun head on the gun body 1, connect the compressed air to the air inlet head 28, the compressed air enters the reversing mechanism in the gun body 1 and enters the cylinder 2 below the cylinder piston through the reversing mechanism, drives the cylinder piston upward to the highest position and maintains it, presses the button to control the reversing of the reversing mechanism, and the compressed air enters the top of the cylinder piston through the reversing mechanism to drive the cylinder piston to move downward, and the cylinder piston drives the booster piston 5 to move downward so that the hydraulic oil enters the piston cavity in front of the tension piston 16 in the pull head assembly along the oil channel. The tension piston 16 moves to the right under the action of the hydraulic oil to generate a pulling force, and the tension piston 16 pulls the anvil connecting sleeve 39 of the gun head to make the jaw clamping flap 44 contract to clamp the rivet core rod and pull it backward to form the rivet tail, and at the same time, the tension piston 16 moves to the right to make the plug rod 18 contact with the push rod 21. At this time, the tension piston 16 is limited by the push rod 21, and the push rod makes the rod seat 17 and When the self-sealing joint formed by the plug rod 18 is opened, the hydraulic oil in the closed cavity at the front end of the pulling piston 16 will flow into the cylinder body on the rear side of the thrust piston 15 along the liquid flow channel of the plug rod 18 through the matching joint, thereby pushing the inner cylinder body 13 to move left. The thrust shaft 14 generates a thrust on the anvil 38 under the action of the inner cylinder body 13, pushing the locking ring on the rivet core rod until the end of the anvil 38 is flush with the end of the gun head shell 36. The locking ring is pushed out and cooperates with the nail cap of the rivet to lock the workpiece, completing the riveting work. The broken core rod will be pushed out of the gun head through the plunger 43 under the action of the plunger spring 53 to facilitate the next riveting work. Release the button and the cylinder piston will reset to the top of the cylinder 2. At the same time, the pulling piston 16 and the inner cylinder body 13 will complete the reset under the action of the reset spring 19. The hydraulic oil on the front side of the pulling piston returns to the booster cylinder 4 along the original path, and the hydraulic oil on the rear side of the thrust piston flows into the oil tank through the outer cylinder body.

[0030] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A pneumatic hydraulic blind rivet gun, comprising a gun body, wherein the gun body comprises an oil tank, a booster cylinder connected to the oil tank, and a pull head assembly, characterized in that: The pulling head assembly includes an outer cylinder body connected to the oil tank, an inner cylinder body is movably installed in the outer cylinder body, a pulling piston is installed at the front end of the inner cylinder body, the piston chamber on the front side of the pulling piston is connected with the boosting cylinder, a thrust piston fixedly connected to the inner cylinder body is installed at the rear end of the outer cylinder body, a pulling piston communicating hole which passes through the pulling piston from front to back is provided on the pulling piston, a self-sealing joint is installed in the pulling piston communicating hole, a mating joint matching the self-sealing joint is installed on the thrust piston, the mating joint includes a push rod for triggering the self-sealing joint, a connecting channel leading to the rear side of the thrust piston is provided in the push rod, and a sealing structure which is sealed and crimped with the self-sealing joint is provided at the front end of the push rod.

2. The pneumatic hydraulic blind rivet gun according to claim 1, characterized in that: A return spring is mounted between the rear side of the tension piston and the inner cylinder body.

3. The pneumatic hydraulic blind rivet gun according to claim 1 or 2, characterized in that: The sealing structure at the front end of the push rod is a conical through hole, and the through hole is sealed with the self-sealing joint.

4. The pneumatic hydraulic blind rivet gun according to claim 3, characterized in that: The self-sealing joint includes a rod seat and a plug rod installed in the rod seat. The plug rod and the rod seat are clearance-matched. A liquid flow channel is provided in the plug rod. A plug rod connecting hole connected to the liquid flow channel is provided on the outer wall of the plug rod. The rod seat and the rear end of the plug rod are sealed by a sealing ring.

5. The pneumatic hydraulic blind rivet gun according to claim 4, characterized in that: The rear end of the plug rod is provided with a conical end head for sealingly cooperating with the ejector rod.

6. The pneumatic hydraulic blind rivet gun according to claim 1 or 2, characterized in that: A hollow shift adjustment shaft is arranged in the mating joint, a connecting hole is opened on the shift adjustment shaft and is connected with the connecting channel, and an adjusting bolt, an adjusting knob and an adjusting indicator ring are arranged at the rear end of the outer cylinder body.

7. The pneumatic hydraulic blind rivet gun according to claim 1 or 2, characterized in that: A reversing mechanism and a cylinder are also arranged in the gun body, and the reversing mechanism is communicated with the cylinder.

8. The pneumatic hydraulic blind rivet gun according to claim 7, characterized in that: A cylinder piston is arranged in the cylinder, a booster piston is arranged in the booster cylinder, and the booster piston and the cylinder piston are fixedly connected via a piston rod.

9. The pneumatic hydraulic blind rivet gun according to claim 8, characterized in that: A gas-liquid isolation ring is arranged between the piston rod and the booster cylinder body.

10. The pneumatic hydraulic blind rivet gun according to claim 8 or 9, characterized in that: A connecting head is arranged on the boosting piston, and the piston rod and the connecting head are connected via threads.

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