A piston rod connection structure capable of improving the sealing performance of a hydraulic cylinder

Abstract

The utility model discloses a kind of piston rod connecting structures capable of improving the sealing performance of hydraulic cylinder, belong to mechanical hydraulic transmission technical field, the connecting structure includes piston rod body and annular piston block, the fastening hole is opened in the inside of annular piston block, the piston rod body is fixedly installed in fastening hole;Annular piston block outer periphery is provided with several side pressure holes, pressure piece and thread top silk piece are provided in side pressure hole, the pressure piece is set in side pressure hole close to one end of fastening hole, and the pressure piece and the piston rod body abut, the pressure piece is away from the side of piston rod body and abuts the thread top silk piece, the thread top silk piece is fixedly installed in side pressure hole;By setting pressure piece and thread top silk piece in side pressure hole, when thread top silk piece is screwed, push pressure piece radial movement, exert lateral pressure to piston rod body and form the mode of lateral constraint, solve the leakage problem existing in the single sealing mode of traditional hydraulic cylinder.

Description

Technical Field

[0001] This utility model relates to the field of mechanical hydraulic transmission technology, specifically to a piston rod connection structure that can improve the sealing performance of a hydraulic cylinder. Background Technology

[0002] In mechanical equipment, hydraulic cylinders are the main components providing mechanical power. The sealing performance of a hydraulic cylinder is a core element of the hydraulic system, directly determining its working efficiency, reliability, lifespan, and the overall system performance. Its primary function is to prevent hydraulic oil from leaking from the high-pressure side to the low-pressure side (internal and external leakage).

[0003] According to the installation location and function, the sealing forms can be divided into three categories: (1) Piston seal: The most important sealing component of the hydraulic cylinder is installed on the piston to isolate the rod chamber and rodless chamber of the hydraulic cylinder and prevent the pressure oil from leaking from the high pressure chamber to the low pressure chamber; (2) Piston rod body seal: The most important anti-leakage sealing method is installed on the inside of the cylinder head to prevent the hydraulic oil from leaking to the outside of the cylinder along the piston rod body. At the same time, it scrapes off the oil film attached to the piston rod body during the return stroke to form an extremely thin lubricating oil film, which plays a lubricating role; (3) Guide support seal: The seal using low friction material is installed on the guide sleeve of the piston and cylinder head to support the piston and piston rod body, prevent direct contact between metal parts, absorb lateral force, ensure the centering and smoothness of the movement, and reduce the wear of the seal.

[0004] However, a single sealing method is insufficient to completely solve the leakage problem of hydraulic cylinders. The main issue is that the piston and piston rod rely on threads for fastening and contact, making it difficult to maintain a proper clearance. Especially during prolonged operation, wear can occur, leading to leakage. Furthermore, the fastening force between the piston and piston rod is generated axially through the threads, without lateral pressure. This can also cause them to loosen during operation, resulting in leakage. Utility Model Content

[0005] To address the problems mentioned in the background section, a piston rod connection structure that improves the sealing performance of hydraulic cylinders is proposed. The technical solution adopted by this utility model is as follows:

[0006] A piston rod connection structure for improving the sealing performance of a hydraulic cylinder includes a piston rod body and an annular piston block. The annular piston block has a through-hole for fastening, and the piston rod body is fixedly installed in the fastening hole. The annular piston block has a plurality of side pressure holes that penetrate the fastening hole on its outer periphery. A side pressure assembly is provided in the side pressure hole, and the side pressure assembly is used to provide lateral pressure to the piston rod body to enhance the connection fastening performance.

[0007] Preferably, the side pressure assembly includes a clamping member and a threaded set screw. The clamping member is disposed at one end of the side pressure hole near the fastening hole, and the clamping member abuts against the outer surface of the piston rod body. The side of the clamping member away from the piston rod body abuts against the threaded set screw, and the threaded set screw is fixedly installed in the side pressure hole.

[0008] Preferably, the threaded set screw is provided with a second thread on its outer periphery, and the inner wall of the side pressure hole is provided with a thread that matches the second thread. The threaded set screw is fixedly installed inside the side pressure hole based on the second thread.

[0009] Preferably, a sealing tape is provided on the outer periphery of the piston rod body that abuts against the annular piston block, the clamping member abuts against the sealing tape, and the clamping member is pressed against the sealing tape based on the threaded set screw.

[0010] Preferably, the annular piston block has a first thread inside the fastening hole, and the annular piston block is fixedly connected to the piston rod body based on the first thread.

[0011] Preferably, the side pressure holes are equidistantly arranged within the annular piston block, and all the side pressure holes are at the same horizontal height.

[0012] The beneficial effects of this utility model's piston rod connection structure, which improves the sealing performance of hydraulic cylinders, are as follows:

[0013] This solution optimizes the stability and sealing of the hydraulic cylinder piston rod body connection through a multi-level constraint mechanism. Using an annular piston block as the core carrier, its fastening holes are threaded to fix the piston rod body, providing axial constraint. The threaded set screw in the side pressure hole drives the clamping component to apply radial pressure, forming lateral constraint. Under compression, the sealing tape forms a dynamic sealing layer, solving the technical problems of the traditional single-seal method in hydraulic cylinders mentioned in the background. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view of an embodiment of a piston rod connection structure that can improve the sealing performance of a hydraulic cylinder according to the present invention.

[0015] Figure 2 This is a three-dimensional structural diagram of the annular piston block in an embodiment of the present invention.

[0016] Among them, 1. Piston rod body; 2. Annular piston block; 201. Fastening hole; 202. Side pressure hole; 211. Sealing tape; 212. First thread; 221. Clamping part; 222. Threaded set screw; 223. Second thread. Detailed Implementation

[0017] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0018] like Figure 1-2 As shown, a piston rod connection structure that can improve the sealing performance of a hydraulic cylinder includes a piston rod body 1 and an annular piston block 2. The annular piston block 2 has a through fastening hole 201 inside, and the piston rod body 1 is fixedly installed in the fastening hole 201. The annular piston block 2 has a plurality of side pressure holes 202 through the fastening hole 201 on its outer periphery. A side pressure component is provided in the side pressure hole 202, and the side pressure component is used to provide lateral pressure to the piston rod body 1 to enhance the connection fastening performance.

[0019] In this embodiment, through-hole fastening holes 201 are provided at both ends of the annular piston block 2. The piston rod body 1 is fixedly installed in the fastening holes 201. This structure achieves axial constraint of the piston rod body 1 through the distribution of multiple holes, distributing the load to avoid stress concentration. At the same time, the through-hole design simplifies the assembly process and ensures quick positioning and installation of the piston rod body 1 and the piston block. This not only ensures that the annular piston block 2 and the piston rod body 1 of the hydraulic cylinder have good locking force, but also ensures a tight fit without loosening during movement, avoiding leakage and thus preventing the sealing performance of the hydraulic cylinder from being affected.

[0020] In one embodiment, the side pressure assembly includes a clamping member 221 and a threaded set screw member 222. The clamping member 221 is disposed at one end of the side pressure hole 202 near the fastening hole 201, and the clamping member 221 abuts against the outer surface of the piston rod body 1. The side of the clamping member 221 away from the piston rod body 1 abuts against the threaded set screw member 222, and the threaded set screw member 222 is fixedly installed in the side pressure hole 202.

[0021] In this embodiment, side pressure holes 202 are evenly arranged around the outer periphery of the annular piston block 2. A clamping member 221 and a threaded setter 222 are installed within these holes. When the threaded setter 222 is tightened, it pushes the clamping member 221 to move radially, applying lateral pressure to the piston rod body 1. This design generates a continuous lateral preload through a mechanical self-locking principle, compensating for gaps caused by vibration or thermal deformation. Furthermore, after the clamping member 221 contacts the piston rod body 1, its elastic deformation capability can adapt to the microscopic roughness of the piston rod body 1 surface, forming a dynamic contact interface. The tightening action of the threaded setter locks the position through the frictional resistance of the threaded pair, preventing the clamping member 221 from retracting due to vibration, thereby maintaining a stable lateral constraint force.

[0022] In one embodiment, the threaded set screw 222 is provided with a second thread 223 on its outer periphery, and the inner wall of the side pressure hole 202 is provided with a thread that matches the second thread 223. The threaded set screw 222 is fixedly installed inside the side pressure hole 202 based on the second thread 223.

[0023] In this embodiment, the threaded set screw 222 is matched and fixed with the second thread 223, and the lateral pressure of the clamping member 221 is converted into a permanent constraint force through the self-locking characteristic.

[0024] In one embodiment, a sealing tape 211 is provided on the outer periphery of the piston rod body 1 that abuts against the annular piston block 2. The clamping member 221 abuts against the sealing tape 211, and the clamping member 221 is pressed against the sealing tape 211 based on the threaded set screw 222.

[0025] In this embodiment, a sealing tape 211 is provided on the outer periphery of the piston rod body 1, and the clamping member 221 squeezes the tape to form a dynamic sealing layer.

[0026] In one embodiment, the annular piston block 2 has a first thread 212 inside the fastening hole 201, and the annular piston block 2 is fixedly connected to the piston rod body 1 based on the first thread 212.

[0027] In this embodiment, a first thread 212 is provided inside the fastening hole 201 of the annular piston block 2, and the piston rod body 1 is fixedly connected to the annular piston block 2 through the thread, providing a high load-bearing and high-reliability axial fixing solution for the hydraulic cylinder.

[0028] In one embodiment, the side pressure holes 202 are equidistantly arranged within the annular piston block 2, and all the side pressure holes 202 are at the same horizontal height.

[0029] In this embodiment, lateral pressure is provided by the lateral pressure component in the lateral pressure hole 202, thereby ensuring that the annular piston block 2 of the hydraulic cylinder and the piston rod body 1 have a good locking force.

[0030] The specific working principle of the piston rod connection structure of this utility model, which can improve the sealing performance of a hydraulic cylinder, is as follows: During installation, the piston rod body 1 is first inserted into the through-fastening hole 201 inside the annular piston block 2. Axial fixation is achieved through the first thread 212 on the inner side of the annular piston block 2 and the thread on the outer circumference of the piston rod body 1, ensuring a tight fit between the two. Subsequently, side pressure components are installed in the side pressure holes 202 evenly distributed on the outer circumference of the annular piston block 2. Each side pressure hole 202 is provided with a clamping member 221 and a threaded set screw 222. One end of the clamping member 221 contacts the outer surface of the piston rod body 1, and the other end abuts against the threaded set screw 222. After assembly, the clamping member 221 is pushed to move radially by tightening the threaded set screw 222, applying lateral pressure to the piston rod body 1. The self-locking characteristic of the threaded pair forms a continuous lateral preload, thereby enhancing the connection and tightness between the piston rod body 1 and the annular piston block 2.

[0031] During operation, when the hydraulic cylinder is working, the side pressure assembly continuously applies lateral pressure through the mechanical self-locking action of the threaded set screw, compensating for gap changes caused by vibration or thermal deformation. Simultaneously, the clamping member 221 and the sealing tape 211 on the outer periphery of the piston rod body 1 form a dynamic sealing layer, effectively preventing internal and external leakage of high-pressure oil. This structure achieves axial constraint on the piston rod body 1 through the multi-hole distribution of fastening holes 201, distributing the load and avoiding stress concentration. The equidistant layout of the side pressure holes 202 ensures uniform pressure transmission. The threaded connection between the annular piston block 2 and the piston rod body 1 provides high load-bearing capacity, while the elastic deformation capability of the clamping member 221 can adapt to the microscopic roughness of the piston rod body 1 surface, forming a dynamic contact interface. The self-locking characteristic of the threaded set screw 222 further locks the position of the clamping member 221, preventing lateral pressure back due to vibration and maintaining stable sealing performance. Ultimately, the synergistic effect of mechanical constraint and dynamic sealing significantly improves the overall sealing reliability of the hydraulic cylinder.

[0032] The present invention and its embodiments have been described above. This description is not restrictive. The accompanying drawings are only one embodiment of the present invention. The actual structure is not limited to this. In short, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the inventive spirit of the present invention, such design should fall within the protection scope of the present invention.

Claims

1. A piston rod connection structure that improves the sealing performance of a hydraulic cylinder, characterized in that: The device includes a piston rod body (1) and an annular piston block (2). The annular piston block (2) has a through fastening hole (201) inside, and the piston rod body (1) is fixedly installed in the fastening hole (201). The annular piston block (2) has several side pressure holes (202) through the fastening hole (201) on its outer periphery. A side pressure component is provided in the side pressure hole (202), and the side pressure component is used to provide lateral pressure to the piston rod body (1) to enhance the connection fastness. The side pressure assembly includes a clamping member (221) and a threaded set screw member (222). The clamping member (221) is disposed at one end of the side pressure hole (202) near the fastening hole (201), and the clamping member (221) abuts against the outer surface of the piston rod body (1). The side of the clamping member (221) away from the piston rod body (1) abuts against the threaded set screw member (222), and the threaded set screw member (222) is fixedly installed in the side pressure hole (202).

2. The piston rod connection structure for improving the sealing performance of a hydraulic cylinder according to claim 1, characterized in that: The outer periphery of the threaded set screw (222) is provided with a second thread (223), and the inner wall of the side pressure hole (202) is provided with a thread that matches the second thread (223). The threaded set screw (222) is fixedly installed inside the side pressure hole (202) based on the second thread (223).

3. The piston rod connection structure for improving the sealing performance of a hydraulic cylinder according to claim 1, characterized in that: A sealing tape (211) is provided on the outer periphery of the piston rod body (1) that abuts against the annular piston block (2). The clamping member (221) abuts against the sealing tape (211), and the clamping member (221) is pressed against the sealing tape (211) based on the threaded set screw (222).

4. The piston rod connection structure for improving the sealing performance of a hydraulic cylinder according to claim 1, characterized in that: The annular piston block (2) has a first thread (212) inside the fastening hole (201), and the annular piston block (2) is fixedly connected to the piston rod body (1) based on the first thread (212).

5. The piston rod connection structure for improving the sealing performance of a hydraulic cylinder according to claim 1, characterized in that: The side pressure holes (202) are equidistantly arranged within the annular piston block (2), and all the side pressure holes (202) are at the same horizontal height.

Images