Hydraulic cylinder structure and riveting equipment applying same

Abstract

The hydraulic cylinder structure comprises a piston rod, an inner hydraulic cylinder barrel and an outer hydraulic cylinder barrel, the inner hydraulic cylinder barrel and the outer hydraulic cylinder barrel are movably connected with the piston rod, and the inner hydraulic cylinder barrel is in sliding connection with the outer hydraulic cylinder barrel; the outer hydraulic cylinder barrel comprises an outer hydraulic cylinder barrel body and a pressing ring fixedly connected with the end of the outer hydraulic cylinder barrel body. One end of the piston rod is of a ball head structure, an arc-shaped through hole is formed in the center of the pressing ring and matched with the ball head structure, the diameter of the arc-shaped through hole is matched with the diameter of the ball head so that the ball head structure can be matched with the arc-shaped through hole in the center of the pressing ring, the diameter of an outer port of the arc-shaped through hole is smaller than that of the inner side, and the ball head is limited in the through hole. The piston rod of the hydraulic cylinder adopts a ball head structure, so that force applied to the piston rod can be better transmitted, the deformation probability of the piston rod is reduced, and the working efficiency is improved; the riveting equipment transmits unbalance loading force through the matching face of the ball head structure and the locking device, the sealing failure frequency is reduced, the service life of the hydraulic cylinder is prolonged, the use efficiency of the hydraulic cylinder is improved, and the steel bar riveting quality is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of riveting and fastening, in particular to the technical field of designing and manufacturing riveting and fastening equipment, belongs to the riveting category (B21J), and specifically relates to a hydraulic cylinder structure and a riveting equipment using the structure. Background Art

[0002] Rebar riveting is a fastening process that has emerged in recent years. It is mainly used in bridges, buildings, large steel structures, reinforced concrete and other fields. At present, most rebar riveting installation tools are driven by hydraulic cylinders. Hydraulic cylinders are the core equipment for rebar riveting operations. Rebar riveting molds in the form of threads or flanges are installed on the cylinder body. Through the reciprocating motion of the cylinder body, the rebar and the sleeve are 100% connected.

[0003] During the riveting process of the existing riveting hydraulic cylinder, the reciprocating motion of the cylinder body causes the mold to generate thrust on the retaining ring on the sleeve, and then the sleeve has a reaction force on the steel bar riveting mold. This force will be transmitted to the cylinder body and the piston rod, causing the cylinder body and the piston rod to deform, resulting in seal failure. When riveting to a certain number of steel bars, the internal leakage caused by seal failure makes the hydraulic cylinder unable to reach the working pressure, resulting in the riveting work cannot be carried out normally, and the seal or even the entire cylinder body needs to be replaced, affecting the quality of steel bar riveting and the construction period. Therefore, it is necessary to design a structure that balances the off-center load force of the steel bar riveting mechanism to solve the above problems of the existing riveting hydraulic cylinder. Summary of the invention

[0004] The purpose of the present invention is to provide a hydraulic cylinder structure and a riveting device using the hydraulic cylinder structure in view of the above-mentioned problems. The present invention can effectively solve the problem of eccentric load of the equipment.

[0005] The present invention is achieved through the following technical solutions:

[0006] A hydraulic cylinder structure, comprising a piston rod, an inner hydraulic cylinder barrel and an outer hydraulic cylinder barrel respectively connected to the piston rod, wherein the inner hydraulic cylinder barrel is slidably connected to the outer hydraulic cylinder barrel; the outer hydraulic cylinder barrel comprises an outer hydraulic cylinder barrel body and a pressure ring fixedly connected to the end of the outer hydraulic cylinder barrel body;

[0007] One end of the piston rod is set as a ball head structure, and an arc-shaped through hole is set in the center of the pressure ring to adapt to the ball head structure. The diameter of the arc-shaped through hole is matched with the diameter of the ball head to make the ball head structure adapt to the arc-shaped through hole in the center of the pressure ring. The outer port diameter of the arc-shaped through hole is smaller than the inner diameter, and the ball head is limited in the through hole.

[0008] The pressure ring is provided with a through hole adapted to the ball head structure, and the ball head structure can be adapted in the hole but cannot pass through the hole, that is, the diameter of the end surface of the pressure ring away from the ball head structure is smaller than the diameter of the ball head structure.

[0009] The arc surface of the pressure ring is adapted to the ball head structure, so that when the piston rod is subjected to an eccentric load, the two will rotate slightly to offset the eccentric load, making the bending deformation of the piston rod as small as possible, ensuring the integrity of the seal and further improving the quality of steel bar riveting and the life of the steel bar riveting installation tools.

[0010] The diameter of the arc surface through hole is matched with the diameter of the ball head so that the ball head structure is adapted to the arc surface through hole in the center of the pressure ring. The diameters of the two are set to be adapted and sealed, so that the two can be tightly matched. If the diameter of the arc surface is too large, the ball head structure and the arc surface cannot form a good surface contact, and the eccentric load force cannot be transmitted well, and the bending deformation of the piston rod cannot be minimized, and the integrity of the seal cannot be guaranteed, and the purpose of improving the quality of steel bar riveting and the life of steel bar riveting installation tools cannot be achieved.

[0011] The outer hydraulic cylinder also includes an outer hydraulic cylinder end cover abutting against the end surface of the outer hydraulic cylinder body, and a locking end cover detachably connected to the outer diameter of the outer hydraulic cylinder body, the outer hydraulic cylinder end cover is fixed between the outer hydraulic cylinder body and the locking end cover, and holes are provided on the locking end cover and the outer hydraulic cylinder end cover, the holes of the locking end cover allow the ball head structure to pass through, the hole on the outer hydraulic cylinder end cover is adapted to the ball head structure, and the pressure ring is arranged in the hole of the locking end cover and fixedly connected to the outer hydraulic cylinder end cover.

[0012] The hole opened on the end cover of the outer hydraulic cylinder is divided into two parts, one part is a straight cylindrical hole, and the other part is a hole adapted to the ball head structure, the inner circular surface of which is arc-shaped and the diameter is adapted to the ball head structure.

[0013] The size of the hole of the locking end cover allows the installation of the pressure ring, the shape of the inner surface of the hole of the pressure ring matches the corresponding position of the ball head structure, the inner circular surface of the hole of the pressure ring is adapted to the ball head structure, and the diameter of the end away from the ball head structure is smaller than the diameter of the ball head structure, thereby preventing the ball head structure from detaching from the pressure ring.

[0014] The ball head structure is arranged between the pressure ring and the outer hydraulic cylinder end cover.

[0015] The outer hydraulic cylinder body is detachably connected to the locking end cover. The outer hydraulic cylinder body and the locking end cover are connected together in a detachable connection manner, and the outer hydraulic cylinder end cover is fixed between the outer hydraulic cylinder body and the locking end cover.

[0016] The inner hydraulic cylinder comprises an inner hydraulic cylinder body and an inner hydraulic cylinder end cover, wherein the inner hydraulic cylinder end cover is fixedly connected to the inner hydraulic cylinder body, and the inner hydraulic cylinder end cover is provided with a hole adapted to the diameter of the piston rod.

[0017] The inner hydraulic cylinder body is detachably connected to the inner hydraulic cylinder end cover.

[0018] Further, the piston rod includes the ball head structure, a piston rod body fixedly connected to the ball head structure, and a piston rod stopper fixedly connected to the piston rod body in a detachable manner, the piston rod stopper abuts against the inner hydraulic cylinder end cover, and the piston rod body is fixedly connected to the piston rod stopper after passing through the hole opened in the inner hydraulic cylinder end cover; channel one and channel two are provided in the piston rod body, the piston rod stopper and the bottom of the inner hydraulic cylinder form cavity one, cavity two is formed between the piston rod stopper and the inner hydraulic cylinder end cover, the channel one connects the cavity one and the conversion joint, and the channel two connects the cavity two and the conversion joint; the conversion joint is detachably connected to the end face of the ball head structure.

[0019] A hole matching the diameter of the piston rod body is formed in the inner hydraulic cylinder end cover, and a hole matching the piston rod is formed in the piston rod stopper. The piston rod body and the piston rod stopper are fixedly connected together in a detachable manner to prevent the piston rod body and the piston rod stopper from detaching.

[0020] The conversion joint is connected to an external hydraulic system to provide hydraulic oil for the hydraulic structure. By setting the channel one and the channel two, the pressure in the chamber one and the chamber two is kept balanced during the sliding process of the inner hydraulic cylinder.

[0021] The diameter of the ball head structure is larger than the diameter of the piston rod body. Only when the diameter of the ball head structure is larger than the diameter of the piston rod body can the ball head structure and the arc surface be well matched, thereby completing the transmission of the eccentric load.

[0022] The present invention also discloses a riveting device, including a sleeve structure and a riveting die structure, which adopts the above hydraulic cylinder structure; the sleeve structure is detachably connected to the outer circle of the outer hydraulic cylinder barrel, and the riveting die is detachably connected to the other end of the inner hydraulic cylinder barrel.

[0023] The sleeve structure is detachably connected to the outer circle of the outer hydraulic cylinder, and the riveting die is detachably connected to the other end of the inner hydraulic cylinder.

[0024] The sleeve structure is detachably connected to the outer circle of the outer hydraulic cylinder barrel, and the sleeve structure is firmly fixed on the outer circle of the outer hydraulic cylinder barrel.

[0025] The riveting die structure comprises a riveting die and a load-bearing U-shaped structure. The riveting die is threadedly connected to the other end of the inner hydraulic cylinder barrel, and the load-bearing U-shaped structure is fixedly connected to the riveting die.

[0026] The riveting die structure is firmly connected to the inner hydraulic cylinder barrel through the detachable connection between the riveting die and the inner hydraulic cylinder barrel.

[0027] The beneficial effects of the present invention are:

[0028] The piston rod of the hydraulic cylinder of the present invention adopts a ball head structure, which can better transmit the force applied to the piston rod by the outside world, thereby reducing the deformation probability of the piston rod and further improving the working efficiency of the hydraulic cylinder; the riveting equipment of the present invention adopts the hydraulic cylinder with the above-mentioned ball head structure, and uses the matching surface of the ball head structure and the locking device to transmit the eccentric load force, thereby reducing the sealing failure frequency of the hydraulic cylinder, improving the service life and use efficiency of the hydraulic cylinder, and further improving the quality of the steel bar riveting work and the life of the steel bar riveting installation tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a front cross-sectional schematic diagram of the hydraulic cylinder structure of the present invention;

[0030] Figure 2 is a front cross-sectional schematic diagram of the riveting device of the present invention;

[0031] Figure 3 is a three-dimensional diagram of the riveting device of the present invention;

[0032] Figure 4 It is another stereoscopic view of the riveting device of the present invention.

[0033] In the figure: 1- hydraulic cylinder, 2- sleeve structure, 3- riveting die structure, 4- rotary joint;

[0034] 11-piston rod, 111-piston rod stopper, 1111-third internal thread, 112-piston rod body, 1121-third external thread, 113-ball head structure, 12-inner hydraulic cylinder barrel, 121-inner hydraulic cylinder body, 1211-second internal thread, 1212-fifth external thread, 122-inner hydraulic cylinder end cover, 1221-second external thread, 123-chamber one, 124-chamber two, 13-external hydraulic cylinder barrel, 131-external hydraulic cylinder barrel body, 1311-first external thread, 1312-fourth external thread, 132-locking end cover, 1321-first internal thread, 133-pressing ring, 134-external hydraulic cylinder barrel end cover;

[0035] 21-sleeve, 22-sleeve mounting seat, 221-fourth internal thread, 23-handle;

[0036] 31-riveting die, 311-fifth internal thread, 32-load-bearing U-shaped structure. DETAILED DESCRIPTION

[0037] The present invention is further described below in conjunction with specific implementation methods. The specific implementation methods are further descriptions of the principles of the present invention and do not limit the present invention in any way. Technologies that are the same or similar to the present invention do not exceed the scope of protection of the present invention.

[0038] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0039] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0040] Example 1

[0041] The hydraulic cylinder structure of this embodiment is as follows: Figure 1 As shown, the hydraulic cylinder includes a piston rod 11, an inner hydraulic cylinder barrel 12 and an outer hydraulic cylinder barrel 13 which are respectively movably connected to the piston rod 11, the inner hydraulic cylinder barrel 12 and the outer hydraulic cylinder barrel 13 are slidably matched, the outer hydraulic cylinder barrel 13 includes an outer hydraulic cylinder barrel body 131 and a pressure ring 133 fixedly connected to the outer hydraulic cylinder barrel body 131, one end of the piston rod 11 is set as a ball head structure 113, and the pressure ring 133 is adapted to the ball head structure 113.

[0042] The pressure ring 133 is provided with an arc-surface through hole adapted to the ball head structure 113 , and the ball head structure 113 can be adapted in the hole but cannot pass through the hole, that is, the diameter of the end surface of the pressure ring 133 away from the ball head structure 113 is smaller than the diameter of the ball head structure 113 .

[0043] The arc-shaped through hole set in the center of the pressure ring 133, its arc-shaped surface can be an arc-shaped concave surface, and the joint part of the ball head structure 113 is set to a matching arc-shaped convex surface, the arc-shaped convex surface and the arc-shaped concave surface are rotatably matched, and the diameter of the arc-shaped concave through hole away from the outer end is smaller than the inner diameter of the through hole, and the ball head will not protrude from the through hole.

[0044] The compression ring 133 is provided with an arc surface adapted to the ball head structure 113. When the piston rod 11 is subjected to an eccentric load, the two can rotate slightly to offset the eccentric load, so as to minimize the bending deformation of the piston rod 11, thereby ensuring the integrity of the seal and further improving the quality of the steel bar riveting and the life of the steel bar riveting installation tools.

[0045] In this embodiment, the diameter of the arc surface is the same as the matching diameter of the ball head structure 113 .

[0046] Setting the diameters of the two to be the same can make the two fit closely. If the diameter of the aforementioned arc surface is too large, the ball head structure 113 cannot form a good surface contact with the aforementioned arc surface, and the eccentric load force cannot be transmitted well, the bending deformation of the piston rod 11 cannot be minimized, and the integrity of the seal cannot be guaranteed, and the purpose of improving the quality of steel bar riveting and the life of the steel bar riveting installation tools cannot be achieved.

[0047] Example 2

[0048] Based on Example 1, as shown in FIG. Figure 1 and Figure 2 As shown, the outer hydraulic cylinder 13 also includes an outer hydraulic cylinder end cover 134 abutting against the end surface of the outer hydraulic cylinder body 131, and a locking end cover 132 detachably connected to the outer diameter of the outer hydraulic cylinder body 131. The outer hydraulic cylinder end cover 134 is fixed between the outer hydraulic cylinder body 131 and the locking end cover 132. The locking end cover 132 and the outer hydraulic cylinder end cover 134 are both provided with holes. The hole of the locking end cover 132 allows the ball head structure 113 to pass through. The hole on the outer hydraulic cylinder end cover 134 is adapted to the ball head structure 113. The pressure ring 133 is arranged in the hole of the locking end cover 132 and is fixedly connected to the outer hydraulic cylinder end cover 134.

[0049] It also includes a conversion joint 4 that is detachably connected to the end surface of the ball head structure 113 .

[0050] The hole on the outer hydraulic cylinder end cover 134 is divided into two parts, one part is a straight cylindrical hole, and the other part is a hole adapted to the ball head structure 113 , the inner circular surface of which is arc-shaped, and the diameter matches the ball head structure 113 .

[0051] The size of the hole of the locking end cover 132 should allow the installation of the pressure ring 133. The inner surface of the hole of the pressure ring 133 is set to be circular. The inner circular surface of the hole of the pressure ring 133 is adapted to the ball head structure 113. The diameter of the hole at the end away from the ball head structure is smaller than the diameter of the ball head structure 113 to prevent the ball head structure 113 from detaching from the pressure ring 133.

[0052] In this embodiment, the detachable connection between the outer hydraulic cylinder body 131 and the locking end cover 132 is a threaded connection. A first external thread 1311 is processed on the outer circle of one end of the outer hydraulic cylinder body 131, and a first internal thread 1321 is processed inside the locking end cover 132. The first external thread 1311 is adapted to the first internal thread 1321.

[0053] The outer hydraulic cylinder body 131 and the locking end cover 132 are connected together by threaded connection, and the outer hydraulic cylinder end cover 134 is fixed between the outer hydraulic cylinder body 131 and the locking end cover 132. The threaded connection structure is simple, does not require additional equipment, does not occupy space, and can achieve lightweight equipment.

[0054] Example 3

[0055] Based on Example 1 or Example 2, Figure 1 and Figure 2 As shown, the inner hydraulic cylinder 12 includes an inner hydraulic cylinder body 121 and an inner hydraulic cylinder end cover 122 . The inner hydraulic cylinder end cover 122 is detachably connected to the inner hydraulic cylinder body 121 , and the inner hydraulic cylinder end cover 122 is provided with a hole adapted to the diameter of the piston rod 11 .

[0056] In this embodiment, the inner hydraulic cylinder end cover 122 and the inner hydraulic cylinder body 121 are detachably connected by a threaded connection. A second inner thread 1211 is processed inside the end of the inner hydraulic cylinder body 121 close to the outer hydraulic cylinder body 131, and a second outer thread 1221 is processed on the outer circle of the inner hydraulic cylinder end cover 122. The second inner thread 1211 is adapted to the second outer thread 1221. The threaded connection structure is simple, does not require additional equipment, does not occupy space, and can achieve lightweight equipment.

[0057] Example 4

[0058] Based on Example 1 or 2 or 3, Figure 1 and Figure 2 As shown, the piston rod 11 includes a ball head structure 113, a piston rod body 112 fixedly connected to the ball head structure 113, a piston rod stopper 111 detachably connected to the piston rod body 112, the piston rod stopper 111 abuts against the inner hydraulic cylinder end cover 122, and the piston rod body 112 is detachably connected to the piston rod stopper 111 after passing through the hole opened in the inner hydraulic cylinder end cover 122; a channel one and a channel two are provided in the piston rod body 112, the piston rod stopper 111 and the bottom of the inner hydraulic cylinder body 121 form a cavity one 123, and a cavity two 124 is formed between the piston rod stopper 111 and the inner hydraulic cylinder end cover 122, the channel one respectively connects the cavity one 123 and the conversion joint 4, and the channel two respectively connects the cavity two 124 and the conversion joint 4.

[0059] A hole matching the diameter of the piston rod body 112 is provided in the inner hydraulic cylinder end cover 122. In the present embodiment, the piston rod body 112 is preferably connected to the piston rod stopper 111 in a detachable manner through the hole provided in the inner hydraulic cylinder end cover 122 by a threaded connection. A third external thread 1121 is provided at the other end of the piston rod body 112, and a hole matching the piston rod body 112 is provided in the piston rod stopper 111. A third internal thread 1111 is machined in the hole. The third internal thread 1111 matches the third external thread 1121 to form a firm connection to prevent the piston rod body 112 from detaching from the piston rod stopper 111.

[0060] The conversion joint 4 is connected to the external hydraulic system to provide hydraulic oil to the chamber 1 123 and the chamber 2 124 of the hydraulic cylinder. By setting the channel 1 and the channel 2, the pressure in the chamber 1 123 and the chamber 2 124 is balanced during the sliding process of the inner hydraulic cylinder barrel.

[0061] In this embodiment, the diameter of the ball head structure 113 is greater than the diameter of the piston rod body 112 .

[0062] Only when the diameter of the ball head structure 113 is larger than the diameter of the piston rod body 112 , can the ball head structure 113 and the arc surface be well matched, thereby completing the transmission of the eccentric load force.

[0063] Example 5

[0064] The riveting equipment of this embodiment is as follows Figures 2 to 4 As shown, it includes a sleeve structure 2 and a riveting mold structure 3, and any hydraulic cylinder structure of the aforementioned embodiments 1-4 is applied. The sleeve structure 2 is detachably connected to the outer circle of the outer hydraulic cylinder barrel 13, and the riveting mold structure 3 is detachably connected to the other end of the inner hydraulic cylinder barrel 12.

[0065] The sleeve structure 2 includes a sleeve 21 , a sleeve mounting seat 22 detachably connected to the sleeve 21 , and a handle 23 fixedly connected to the sleeve mounting seat 22 .

[0066] In this embodiment, the sleeve structure 2 is detachably connected to the outer circle of the outer hydraulic cylinder 13 by a threaded connection. A fourth external thread 1312 is processed on the outer circle of the other end of the outer hydraulic cylinder 13, and a fourth internal thread 221 is processed on the inner circle surface of the sleeve mounting seat 22. The fourth external thread 1312 is adapted to the fourth internal thread 221.

[0067] Through the adaptation of the fourth external thread 1312 and the fourth internal thread 221 , the sleeve structure 2 is firmly fixed on the outer circle of the outer hydraulic cylinder body 131 .

[0068] The riveting die structure 3 includes a riveting die 31 and a load-bearing U-shaped structure 32 . The riveting die 31 is detachably connected to the other end of the inner hydraulic cylinder 12 , and the load-bearing U-shaped structure 32 is fixedly connected to the riveting die 31 .

[0069] In this embodiment, the detachable connection between the riveting mold structure 31 and the other end of the inner hydraulic cylinder 12 is a threaded connection. The inner surface of the riveting mold structure 31 is processed with a fifth internal thread 311, and the other end of the inner hydraulic cylinder 12 is processed with a fifth external thread 1212. The fifth internal thread 1212 is adapted to the fifth external thread 311.

[0070] The riveting die structure 31 and the inner hydraulic cylinder barrel 12 are firmly connected by threaded connection between the riveting die structure 31 and the inner hydraulic cylinder barrel 12 .

[0071] The detachable connection method in the aforementioned embodiment is not limited to threaded connection, but may also be other connection methods that can achieve a stable connection between two components, such as bolt connection, screw connection, interference fit or other methods to achieve a stable connection.

Claims

1. A hydraulic cylinder structure, characterized in that: It comprises a piston rod, an inner hydraulic cylinder and an outer hydraulic cylinder respectively connected to the piston rod, wherein the inner hydraulic cylinder is slidably connected to the outer hydraulic cylinder; the outer hydraulic cylinder comprises an outer hydraulic cylinder body and a pressure ring fixedly connected to the end of the outer hydraulic cylinder body; One end of the piston rod is set as a ball head structure, and an arc-shaped through hole is set in the center of the pressure ring to adapt to the ball head structure. The diameter of the arc-shaped through hole is matched with the diameter of the ball head to make the ball head structure adapt to the arc-shaped through hole in the center of the pressure ring. The outer port diameter of the arc-shaped through hole is smaller than the inner diameter, and the ball head is limited in the through hole.

2. The hydraulic cylinder structure according to claim 1, characterized in that: The outer hydraulic cylinder also includes an outer hydraulic cylinder end cover abutting against the end surface of the outer hydraulic cylinder body, and a locking end cover detachably connected to the outer diameter of the outer hydraulic cylinder body; the outer hydraulic cylinder end cover is fixed between the outer hydraulic cylinder body and the locking end cover, and holes are provided on the locking end cover and the outer hydraulic cylinder end cover, the holes of the locking end cover allow the ball head structure to pass through, the hole on the outer hydraulic cylinder end cover is adapted to the ball head structure, and the pressure ring is arranged in the hole of the locking end cover and fixedly connected to the outer hydraulic cylinder end cover.

3. The hydraulic cylinder structure according to claim 2, characterized in that: The hole opened on the end cover of the outer hydraulic cylinder barrel includes two parts, the front part is a cylindrical hole with equal diameter, and the rear part is an arc-shaped hole adapted to the ball head structure, the inner circular surface of which is arc-shaped and the diameter is adapted to the ball head structure.

4. The hydraulic cylinder structure according to claim 2, characterized in that: The inner hydraulic cylinder comprises an inner hydraulic cylinder body and an inner hydraulic cylinder end cover, wherein the inner hydraulic cylinder end cover is fixedly connected to the inner hydraulic cylinder body, and the inner hydraulic cylinder end cover is provided with a hole adapted to the diameter of the piston rod.

5. The hydraulic cylinder structure according to claim 4, characterized in that: The inner hydraulic cylinder body is detachably connected to the inner hydraulic cylinder end cover.

6. The hydraulic cylinder structure according to any one of claims 2 to 5, characterized in that: The piston rod includes the ball head structure, a piston rod body fixedly connected to the ball head structure, and a piston rod stopper fixedly connected to the piston rod body in a detachable manner; the piston rod stopper abuts against the inner hydraulic cylinder end cover; the piston rod body is fixedly connected to the piston rod stopper after passing through the hole opened in the inner hydraulic cylinder end cover; channel one and channel two are provided in the piston rod body, the piston rod stopper and the bottom of the inner hydraulic cylinder form cavity one, cavity two is formed between the piston rod stopper and the inner hydraulic cylinder end cover, the channel one connects the cavity one and the conversion joint detachably connected to the end face of the connecting ball head structure, and the channel two connects the cavity two and the conversion joint detachably connected to the end face of the connecting ball head structure.

7. The hydraulic cylinder structure according to claim 6, characterized in that: The diameter of the ball head structure is greater than the diameter of the piston rod body; the ball head structure is limitedly arranged between the pressure ring and the end cover of the outer hydraulic cylinder barrel.

8. A riveting device, comprising a sleeve structure and a riveting die structure, characterized in that: The hydraulic cylinder structure according to any one of claims 1 to 7 is adopted; the sleeve structure is detachably connected to the outer circle of the outer hydraulic cylinder barrel of the hydraulic cylinder structure, and the riveting die is detachably connected to the other end of the inner hydraulic cylinder barrel of the hydraulic cylinder structure.

9. The riveting device according to claim 8, characterized in that: The sleeve structure comprises a sleeve, a sleeve mounting seat detachably connected to the sleeve, and a handle fixedly connected to the sleeve mounting seat, and the sleeve mounting seat is detachably connected to the outer circle of the outer hydraulic cylinder.

10. The riveting device according to claim 8, characterized in that: The riveting die structure comprises a riveting die and a load-bearing U-shaped structure. The riveting die is detachably connected to the other end of the inner hydraulic cylinder barrel, and the load-bearing U-shaped structure is fixedly connected to the riveting die.

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