A hydraulic riveting machine with top-feeding nails

Abstract

The present invention discloses a hydraulic riveting machine with top-feeding rivets. The machine frame is equipped with a hydraulic cylinder and a female mold base. The cylinder contains a piston, a composite piston rod, and a return spring. The lower end of the cylinder base is equipped with a connecting seat. A rivet box is provided on one side of the connecting seat. The lower end of the composite piston rod extends into the hollow chamber of the connecting seat and abuts against the rivet inside it, thereby pushing the rivet. The female mold base is provided with a first stepped hole, the small diameter section of which is slidably connected to the mold core. The upper end of the mold core is an integrally formed lower ejector rod. A ejector rod spring is provided between the top of the cavity in the mold core and the bottom end of the first stepped hole. An opening and closing female mold tray is installed on the step of the first stepped hole. A four-petal opening and closing female mold with a combined spring is placed on the tray. An opening and closing female mold shield is installed on the top of the female mold base. The present invention can solve the problem of existing riveting machines that when the angle iron hole diameter is too large, the iron sheet is stretched and the rivet cannot be smoothly passed through the angle iron hole. The processing precision requirements of the angle iron hole are reduced, the riveting efficiency is improved, and it is convenient for industrial application.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical processing, in particular to a hydraulic riveting machine for feeding nails from above. Background Art

[0002] Hydraulic riveting machines with top-feed rivets are also known as hydraulic riveting machines, hydraulic riveting machines, and sheet metal riveting machines. They utilize hydraulic press equipment and specialized connecting dies to create a sudden, intense, and high-pressure process. Based on the cold extrusion deformation (upsetting) of the rivet material, they can connect two or more layers of sheet metal of varying materials and thicknesses. They are suitable for connecting steel, stainless steel, aluminum, and non-metallic interlayers. Traditional riveting machines operate in five steps: insertion, alignment, piercing, displacement, and riveting. Each rivet requires the hydraulic rod to retract and retract twice, resulting in low riveting efficiency.

[0003] Chinese patent CN111390097A discloses an improved hydraulic riveting machine with bottom-feeding. By setting a floating base at the bottom of the machine body, nail feeding, perforation and riveting are completed in one hydraulic feed without the need for shift adjustment, which greatly simplifies the riveting process and improves riveting efficiency.

[0004] However, the hydraulic rivet machine that feeds nails from the bottom feeds nails upward through the rivet seat on the bracket, and has high requirements for the dimensional accuracy of the angle iron holes. Since the angle iron holes are generally processed by punching and the punching dies used have no unified standards, it is not easy to ensure that the dimensional tolerance of the angle iron holes meets the use requirements of the rivet machine. When the angle iron hole is too large, the pure shearing process cannot be achieved when the rivet is pierced through the iron sheet, resulting in punching failure; when the angle iron hole is too small (often caused by punch wear), the rivet cannot be pierced through the iron sheet and becomes stuck, causing the riveting process to be interrupted or even damage to the riveting machine components. Summary of the Invention

[0005] The present invention aims to provide a hydraulic riveting machine with top-feeding nails, so as to solve the problem that the existing hydraulic riveting machine with bottom-feeding nails has high requirements on the dimensional accuracy of diagonal iron holes.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The cam is secured to the upper edge of the hydraulic cylinder to allow the cam to move forward and backward, and the cam is secured to the lower edge of the hydraulic cylinder to allow the cam to move forward and backward. A push rod spring is connected between the inner bottoms, an opening and closing female mold tray is installed on the step surface of the first step hole, a four-petal opening and closing female mold is placed on the opening and closing female mold tray, the opening and closing female mold includes an integrated rotating center joint at the bottom, a vertical arm in the middle and an end head at the top, an opening and closing female mold shield is installed on the top of the female mold base, the opening and closing female mold shield is provided with a second step hole that passes through from top to bottom, the second step hole is divided into a small diameter section, a middle diameter section and a large diameter section from top to bottom, the end head of the opening and closing female mold is located in the small diameter section of the second step hole, the end heads of the four-petal opening and closing female mold are surrounded by the lower push rod to form a channel, the shoulder formed by the vertical arm and the end head of the opening and closing female mold is located in the middle diameter section of the second step hole, and a merging spring is connected between the side wall of the large diameter section of the second step hole and the opening and closing female mold.

[0008] The cam is provided with a third groove which is provided with a groove for sliding the cam into the groove, and the cam is provided with a third groove which is provided with a groove for sliding the cam into the groove.

[0009] Preferably, a rivet box for loading rivets is provided on one side of the connecting seat, a rivet push plate for pushing rivets is provided on the side of the rivet box away from the connecting seat, the rivet push plate is connected to the rivet box through a thrust spring, and a clamping mechanism is provided on the connecting seat that can ensure the coaxiality of the rivets in the hollow cavity.

[0010] Preferably, the connecting seat is provided with a second radial through groove, and the side walls of the second radial through groove are provided with a pair of rivet supporting arms and a pair of limiting columns, the limiting columns are located on the inner side of the rivet supporting arms, and the rivet supporting arms and the limiting columns form a clamping mechanism, and the supporting arms rely on the torsion spring on their rotating shaft to achieve the clamping positioning of the rivet and the giving way when the rivet is pressed down.

[0011] Preferably, a compressed air inlet interface is provided at the bottom of the frame, and the compressed air inlet interface is connected to the small diameter section of the first stepped hole. A circle of ventilation grooves is provided on the top of the mold core, and air blowing and chip removal holes are provided between the ventilation grooves and the cavity of the mold core. An exhaust gap is left between the lower push rod and the end of the opening and closing female mold.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention, through the design of an upper nail feeding mechanism and a lower four-petal opening and closing female die, and the use of rivets customized for the riveting machine, can ensure that the aperture of the opening and closing female die end and the rivet form an optimal shear, greatly reducing the dimensional deviation requirements for the angle iron hole. It only requires that the angle iron hole diameter be larger than the rivet diameter. The upper deviation of the angle iron hole between 0.1 and 1 does not affect the riveting speed and quality, greatly reducing the processing accuracy requirements and usage conditions of the angle iron hole, which is conducive to industrial application. At the same time, the opening and closing female die can rotate about the center of rotation cylindrical surface, facilitating the withdrawal of the rivet head after upsetting. The entire riveting process only requires one reciprocating motion of the piston, without the need for shifting and adjustment, thereby improving riveting efficiency. The limiting groove and limiting steel ball designed in the present invention, in conjunction with the locking pawl and the locking groove, complete the early downward push of the rivet during the piston reset process. In conjunction with the use of the clamping mechanism, the coaxiality of the rivet push rod, rivet and angle iron hole is guaranteed, ensuring the convenience of riveting machine operation, riveting speed and riveting quality. In addition, the design of the air-blowing chip removal holes and exhaust gaps can allow the discs produced by shearing the iron sheet to be blown off after the lower push rod is pushed out, and prevent the iron chips and iron sheets produced by riveting from falling into the female mold base, affecting the operation of the device, thereby improving the working stability of the riveting machine and the service life of its components. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the structure of a hydraulic riveting machine with top-feeding provided by an embodiment of the present invention pushing rivets to a preparatory position;

[0015] Figure 2 A schematic structural diagram of a rivet in a hydraulic riveting machine with top feeding provided by an embodiment of the present invention before the rivet is pushed out of the hollow cavity;

[0016] Figure 3 A schematic structural diagram of a rivet box provided in an embodiment of the present invention;

[0017] Figure 4A front sectional view and a top view of the opening and closing female mold provided in an embodiment of the present invention;

[0018] Figure 5 A schematic structural diagram of a composite piston rod provided in an embodiment of the present invention;

[0019] Figure 6 A schematic diagram of the structure of the connection between the piston rod body and the rivet push rod provided in an embodiment of the present invention when the steel ball slides out of the upper groove after the engagement of the locking pawl.

[0020] Among them, the figure marks include: 1. frame; 2. cylinder seat; 3. female mold base; 4. hydraulic cylinder; 5. piston; 6. piston rod body; 7. rivet push rod; 8. return spring; 9. connecting seat; 10. upper limit groove; 11. lower limit groove; 12. nail feeding spring; 13. compression spring; 14. limiting steel ball; 15. positioning pawl; 16. slot; 17. rivet box; 18. rivet support arm; 19. limiting column; 20. mold core; 21. lower push rod; 22. push rod spring; 23. opening and closing female mold tray; 24. opening and closing female mold; 25. opening and closing female mold shield; 26. merging spring; 27. compressed air inlet interface; 28. ventilation groove; 29. ​​air blowing and chip removal hole; 30. exhaust gap. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0022] like Figure 1 and Figure 2 As shown, a hydraulic riveting machine with top-feeding rivets includes a frame 1, with a cylinder base 2 and a die base 3 mounted at the upper and lower ends of the frame 1, respectively. A hydraulic cylinder 4 is detachably connected to the cylinder base 2. A piston 5 and a composite piston rod are disposed within the hydraulic cylinder 4. A piston seal is mounted on the piston 5. The tail end of the composite piston rod is fixed to the piston 5. A return spring 8 is disposed between the inner bottom wall of the hydraulic cylinder 4 and the piston 5. The return spring 8 is sleeved on the composite piston rod. During operation, hydraulic oil enters the hydraulic cylinder 4, pushing the piston 5 and the composite piston rod downward, compressing the return spring 8 to subsequently reset the piston 5 and the composite piston rod.

[0023] refer to Figure 5 and Figure 6The composite piston rod includes a piston rod body 6 and a rivet push rod 7. A third stepped hole opening downward is provided at the bottom of the piston rod body 6. The third stepped hole includes a small diameter section at the top and a large diameter section at the bottom. The large diameter section of the third stepped hole is provided with an upper limit groove 10 and a lower limit groove 11. The rivet push rod 7 is slidably connected to the large diameter section of the third stepped hole. A circular hole is also provided at the top center of the rivet push rod 7. A nail feeding spring 12 is connected between the bottom of the circular hole and the top end of the small diameter section of the third stepped hole. The rivet push rod 7 is provided with a transverse through hole. A compression spring 13 is placed in the transverse through hole. Limiting steel balls 14 that cooperate with the limiting grooves are provided at both ends of the compression spring 13.

[0024] A hollow connecting seat 9 is fixed to the bottom of the cylinder body of the hydraulic oil cylinder 4. The connecting seat 9 is provided with a first radial through groove. The side wall of the first radial through groove is provided with a pair of locking pawls 15. The locking pawl 15 relies on the torsion spring on its rotating shaft to make the inner side of its lower end always contact the outer side of the rivet push rod 7. The rivet push rod 7 is provided with a slot 16 that cooperates with the locking pawl 15. During the reset process of the composite piston rod, the locking pawl 15 is clamped into the slot 16, the rivet push rod 7 stops moving up, and the piston rod body 6 continues to reset, so that the limiting steel ball 14 exits the upper limit groove 10, and the nail feeding spring 12 pushes the rivet push rod 7 downward. Finally, the limiting steel ball 14 is clamped into the lower limit groove 11, completing the pushing of the rivet. Figure 3 A rivet box 17 for loading rivets is provided on one side of the connecting seat 9. A rivet push plate for pushing rivets is provided on the side of the rivet box 17 away from the connecting seat 9. The rivet push plate is connected to the rivet box 17 via a thrust spring to automatically push the rivets to the bottom of the hollow chamber of the connecting seat 9. The connecting seat 9 is provided with a second radial through-slot. The sidewalls of the second radial through-slot are provided with a pair of rivet support arms 18 and a pair of limiting posts 19. The limiting posts 19 are located inside the rivet support arms 18. The rivet support arms 18 and the limiting posts 19 form a clamping mechanism. The support arms 18 rely on the torsion spring on their rotating shaft to clamp the rivet in place and give way when the rivet is pressed down, thereby ensuring the coaxiality of the rivet in the hollow chamber. The head end of the rivet push rod 7 extends into the hollow chamber of the connecting seat 9 and abuts against the rivet in the hollow chamber.

[0025] The female mold base 3 is provided with a first stepped hole with a top opening, and the small diameter section at the bottom of the first stepped hole is slidably connected to the mold core 20, and the upper end of the mold core 20 is integrally formed with a lower ejector rod 21. A cavity opening downward is provided in the mold core 20, and an ejector spring 22 is connected between the inner top of the cavity and the inner bottom of the first stepped hole. An opening and closing female mold tray 23 is installed on the step surface of the first stepped hole, and a four-petal opening and closing female mold 24 is installed on the opening and closing female mold tray 23. The opening and closing female mold 24 includes a rotary center joint integrated at the bottom, a vertical arm in the middle and an end head at the top. The rotary center joint is a horizontal cylinder, the vertical arm is set at 90 degrees longitudinally, and the end head is aligned with the vertical arm. A vertically connected cylinder, an opening and closing mold shield 25 is installed on the top of the mold base 3, and the opening and closing mold shield 25 is provided with a second stepped hole that passes through from top to bottom. The second stepped hole is divided into a small diameter section, a medium diameter section and a large diameter section from top to bottom. The end of the opening and closing mold 24 is located in the small diameter section of the second stepped hole, and the end of the opening and closing mold 24 is flush with the upper end surface of the opening and closing mold shield 25 when it is closed. The end of the four-petal opening and closing mold 24 is surrounded by the lower push rod 21 to form a channel. The shoulder formed by the vertical arm and the end of the opening and closing mold 24 is located in the medium diameter section of the second stepped hole. A merging spring 26 is connected between the side wall of the large diameter section of the second stepped hole and the opening and closing mold 24. During the downward pressing process of the rivet ejector pin 7, the rivet contacts the iron sheet in the iron hole, and a shear is formed between the end of the opening and closing female die 24 and the rivet. After the iron sheet is penetrated, the rivet continues to be pressed down, and the ejector spring 22 is compressed by the lower ejector pin 21, and the upsetting of the rivet is finally completed. At this time, the opening and closing female die 24 can rotate around its rotary center joint, and the four-petal opening and closing female die 24 opens to facilitate the withdrawal of the rivet after upsetting. After the rivet is withdrawn, the four-petal opening and closing female die 24 closes under the action of the merging spring 26. Figure 4 .

[0026] A compressed air inlet interface 27 is provided at the bottom of the frame 1, and the compressed air inlet interface 27 is connected to the small diameter section of the first stepped hole. A circle of ventilation grooves 28 is provided on the top of the core 20, and a blowing and chip removal hole 29 is provided between the ventilation groove 28 and the cavity of the core 20. An exhaust gap 30 is left between the lower push rod 21 and the end of the opening and closing female mold 24 to prevent iron filings and iron sheets generated during the riveting process from falling into the female mold base 3 and affecting the operation of the device.

[0027] The specific implementation process is as follows:

[0028] The row of rivets is placed in the rivet box 17, and the rivet push plate sends the rivets into the connecting seat 9 through elastic force, and the front end rivet is just below the rivet push rod 7; hold the frame 1, insert the exposed rivet into the angle iron hole pre-punched by the angle iron, and make the angle iron and the iron sheet basically parallel to the upper end surface of the opening and closing female mold shield 25; operate the hydraulic switch, and the hydraulic oil enters the hydraulic cylinder 4 from the oil inlet to push the piston 5 downward, the piston rod body 6 moves downward, and the iron sheet and the opening and closing female mold shield 25 are basically parallel. The hydraulic oil in the hydraulic cylinder 4 is discharged, and the piston 5 returns to its original position under the action of the return spring 8, and the piston rod body 6 drives the rivet push rod 7 to move up, and the rivet push rod 7 is pushed upward. The rod spring 22 causes the mold core 20 to move upward and reset, while the lower push rod 21 pushes out the disc produced by the rivet punching the iron sheet. After the rivet push rod 7 moves up a certain distance, the positioning pawl 15 is engaged with the card slot 16 to prevent the rivet push rod 7 from moving up. The piston rod body 6 continues to move up, causing the limiting steel ball 14 to exit the upper limit slot 10. The previously compressed nail feeding spring 12 pushes the rivet push rod 7 downward, and finally the limiting steel ball 14 is engaged with the lower limit slot 11, completing the pushing of the rivet. During the operation of the entire device, compressed air is connected to the compressed air inlet interface 27. The compressed air mainly blows off the iron chips and iron sheets produced during the riveting process along the path of the small diameter section of the first stepped hole, the cavity of the mold core 20, the air blowing and chip removal hole 29, the ventilation groove 28 and the exhaust gap 30.

[0029] The above is only an embodiment of the present invention, and the common knowledge such as the specific technical solutions and / or characteristics in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. A hydraulic riveting machine for feeding nails from above, comprising a frame (1), wherein a cylinder seat (2) and a female die base (3) are respectively mounted on the upper and lower ends of the frame (1), a hydraulic cylinder (4) is mounted on the cylinder seat (2), the hydraulic cylinder (4) is provided with a piston (5) and a composite piston rod, the tail end of the composite piston rod is fixed on the piston (5), and a return spring (8) is provided between the inner bottom wall of the hydraulic cylinder (4) and the piston (5), characterized in that: The bottom of the oil cylinder seat (2) is fixedly connected with a hollow connecting seat (9), and the head end of the composite piston rod extends into the hollow chamber of the connecting seat (9) and abuts against the rivet in the hollow chamber; the female mold base (3) is provided with a first stepped hole with a top opening, and the small diameter section at the bottom of the first stepped hole is slidably connected with a mold core (20), and the upper end of the mold core (20) is integrally formed with a lower push rod (21), and a cavity opening downward is provided in the mold core (20), and a push rod spring (22) is connected between the inner top of the cavity and the inner bottom of the first stepped hole, and an opening and closing female mold tray (23) is installed on the step surface of the first stepped hole, and a four-petal opening and closing female mold (24) is placed on the opening and closing female mold tray (23). The opening and closing female mold (24) includes an integrated rotary center joint at the bottom, a vertical arm in the middle and an end at the top. An opening and closing female mold shield (25) is installed at the top of the female mold base (3). The opening and closing female mold shield (25) is provided with a second stepped hole that passes through from top to bottom. The second stepped hole is divided into a small diameter section, a medium diameter section and a large diameter section from top to bottom. The end of the opening and closing female mold (24) is located in the small diameter section of the second stepped hole. The end of the four-petal opening and closing female mold (24) is surrounded by the lower push rod (21) to form a channel. The shoulder formed by the vertical arm and the end of the opening and closing female mold (24) is located in the medium diameter section of the second stepped hole. A merging spring (26) is connected between the side wall of the large diameter section of the second stepped hole and the opening and closing female mold (24).

2. The hydraulic riveting machine with top-feeding according to claim 1, characterized in that: The composite piston rod comprises a piston rod body (6) and a rivet push rod (7), the piston rod body (6) is provided with a third stepped hole opening downward, the third stepped hole comprises a small diameter section at the top and a large diameter section at the bottom, the large diameter section of the third stepped hole is provided with an upper limit groove (10) and a lower limit groove (11), the rivet push rod (7) is slidably connected to the large diameter section of the third stepped hole, a circular hole is provided at the top of the rivet push rod (7), a nail feeding spring (12) is connected between the bottom of the circular hole and the inner top of the small diameter section of the third stepped hole, the rivet push rod (7) is provided with a circular hole, and a nail feeding spring (12) is connected between the bottom of the circular hole and the inner top of the small diameter section of the third stepped hole. A transverse through hole is provided on the upper part of the rivet push rod (7), a compression spring (13) is placed in the transverse through hole, and limiting steel balls (14) are provided at both ends of the compression spring (13) to cooperate with the limiting groove. The connecting seat (9) is provided with a first radial through groove, and a pair of locking pawls (15) are provided on the side wall of the first radial through groove. The locking pawls (15) rely on the torsion spring on the rotating shaft to make the inner side of the lower end always contact with the outer side of the rivet push rod (7), and the rivet push rod (7) is provided with a locking groove (16) to cooperate with the locking pawl (15).

3. The hydraulic riveting machine with top-feeding according to claim 2, characterized in that: A rivet box (17) for loading rivets is provided on one side of the connecting seat (9), and a rivet push plate for pushing rivets is provided on the side of the rivet box (17) away from the connecting seat (9). The rivet push plate is connected to the rivet box (17) through a thrust spring, and a clamping mechanism capable of ensuring the coaxiality of the rivets in the hollow cavity is provided on the connecting seat (9).

4. The hydraulic riveting machine with top-feeding according to claim 3, characterized in that: The connecting seat (9) is provided with a second radial through groove, and the side wall of the second radial through groove is provided with a pair of rivet supporting arms (18) and a pair of limiting columns (19), wherein the limiting columns (19) are located on the inner side of the rivet supporting arms (18), and the rivet supporting arms (18) and the limiting columns (19) form a clamping mechanism, wherein the supporting arms (18) rely on the torsion spring on the rotating shaft to achieve the clamping and positioning of the rivet and the giving way when the rivet is pressed down.

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