Piston rod and piston embedded structure for lift cylinder of forklift truck

Abstract

The utility model discloses a fork truck lifting oil cylinder piston rod and piston embedded structure in the technical field of hydraulic cylinder, including piston piece, piston rod and cylinder barrel, piston piece has the convex end and piston end, piston rod is used for with piston piece connection, and its inner wall is provided with first groove, and the outer wall of convex end is provided with the second groove corresponding with first groove, and the steel wire baffle ring is clamped with first groove and second groove, and the piston rod end face is provided with second chamfer, to realize axial lock of piston piece and piston rod, piston piece drives piston rod reciprocating motion in cylinder barrel after being pressed, the cooperation of groove and steel wire baffle ring is embedded fixed in this application, avoids the problem of lateral load that screw connection is influenced by coaxial error, makes piston rod movement more stable, and the processing and assembly efficiency are higher, and be applicable to fork truck lifting oil cylinder and other hydraulic system.

Description

Technical Field

[0001] This utility model relates to a piston rod and piston embedded structure for a forklift lifting cylinder, belonging to the field of hydraulic cylinder technology. Background Technology

[0002] As one of the most critical actuators in a forklift lifting system, the hydraulic cylinder's performance directly affects the safety and stability of the vehicle during loading, unloading, lifting, and stacking of goods. The lifting cylinder typically consists of a cylinder barrel, piston, piston rod, and sealing components. The connection structure between the piston and piston rod plays a crucial role in maintaining the system's coaxiality, reducing lateral forces, and ensuring smooth reciprocating motion.

[0003] In existing technologies, pistons and piston rods are mostly fixed by threaded connections, supplemented by anti-loosening structures to prevent loosening during high-frequency reciprocating motion. However, since the piston rods of forklift lifting cylinders are usually long and have a small diameter, it is easy to encounter problems in ensuring coaxiality and straightness during the machining process. This makes the threaded connection susceptible to lateral loads during assembly and operation. When the piston reciprocates in the cylinder, the coaxial deviation at the threaded connection will further amplify the lateral load, causing local stress concentration, which in turn causes the slender piston rod to bend slightly, suffer long-term fatigue, or even undergo permanent deformation. In addition, the threaded structure requires a longer connection length, increasing machining costs, and the assembly process is complex, making it difficult to meet the needs of high-efficiency production. Utility Model Content

[0004] The purpose of this invention is to solve the problems of the connection method between the piston and piston rod in the existing forklift lifting cylinder, which is susceptible to lateral loads at the connection point, occupies a large structural space, and has low assembly efficiency.

[0005] To solve the above-mentioned technical problems, this utility model is implemented using the following technical solution: A piston rod and piston embedded structure for a forklift lifting cylinder is provided, comprising: a piston component, including a protruding end and a piston end; A piston rod is connected to a piston component. The inner wall of the piston rod is provided with a first groove, and the outer wall of the protruding end is provided with a second groove corresponding to the first groove. A wire retaining ring is engaged between the first groove and the second groove, and the piston rod and the piston component are connected by the wire retaining ring; a second chamfer is provided at the end face of the piston rod; The cylinder barrel, and the piston component drives the piston rod to reciprocate within the cylinder barrel.

[0006] Furthermore, the piston component and the piston rod are in a clearance fit.

[0007] Furthermore, the wire retaining ring is made of elastic steel wire and has an open annular structure.

[0008] Furthermore, the diameter of the wire retaining ring is greater than the maximum diameter of the protruding end.

[0009] Furthermore, the diameter of the wire retaining ring is equal to the maximum diameter of the protruding end.

[0010] Furthermore, the protruding end is integrally formed with the piston end.

[0011] Furthermore, the first groove and the second groove are arranged opposite each other in the axial direction.

[0012] Furthermore, the protruding end is provided with a first chamfer.

[0013] Compared with the prior art, the beneficial effects achieved by this utility model are as follows: 1. This utility model designs the piston component as a structure including a protruding end and a piston end, with the protruding end inserted into the inner cavity of the piston rod. At the same time, a first groove and a second groove are respectively provided on the inner wall of the piston rod and the outer wall of the protruding end, so that the two can be locked together by a steel wire retaining ring. This structure does not rely on traditional threaded fit, thus effectively avoiding the problem of bending caused by lateral loads during reciprocating motion due to the difficulty in ensuring coaxiality of the slender piston rod. This makes the straightness of the piston rod more stable and improves the safety and durability of the hydraulic cylinder during operation.

[0014] 2. This utility model provides a first chamfer at the front end of the protruding end, which allows for stable insertion of the piston component into the piston rod during assembly. Simultaneously, a second chamfer is provided on the end face of the piston rod, allowing the wire retaining ring to gradually enter between the two grooves and form a lock during radial elastic deformation, significantly improving the smoothness and reliability of the assembly process. The cooperation of the first and second grooves on the wire retaining ring ensures stable axial positioning of the piston component, preventing axial slippage during reciprocating motion or pressure changes, thus maintaining good sealing and smooth movement. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view of the piston rod and piston embedded structure for the forklift lifting cylinder proposed in this utility model.

[0016] Figure label: 1. Piston rod; 2. Wire retaining ring; 3. Piston assembly; 4. Cylinder; 5. First chamfer; 6. Second chamfer. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0018] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0019] like Figure 1 As shown, this embodiment provides a piston rod and piston embedded structure for a forklift lifting cylinder, including a piston part 3, a piston rod 1 and a cylinder 4. The piston part 3 is composed of a protruding end and a piston end, which are integrally formed. The protruding end is located on the front side of the piston part 3 and is used to embed with the piston rod 1.

[0020] The front end of the protrusion is provided with a first chamfer 5. The first chamfer 5 can be an arc-shaped structure or a beveled structure. The purpose is to provide guidance when the piston rod 1 is inserted into the piston part 3.

[0021] The piston rod 1 has a first groove on its inner wall and a second groove on its outer wall at the protruding end. The first groove and the second groove are arranged opposite to each other to form a locking area for the steel wire retaining ring 2 to engage. The piston component 3 and the piston rod 1 are fitted with a clearance to prevent the slender piston rod 1 from bending.

[0022] The piston rod 1 is also provided with a second chamfer 6 at its end face. The function of the second chamfer 6 is to provide guidance when the wire retaining ring 2 is installed and the piston 3 is pushed into the piston rod 1, so that the wire retaining ring 2 does not interfere during the radial elastic deformation process.

[0023] The steel wire retaining ring 2 is made of elastic steel wire and has an open ring structure. It has good radial elasticity and restoring force, and radial expansion and contraction during installation is achieved through its open end.

[0024] In a preferred embodiment, the diameter of the wire retaining ring 2 is larger than the maximum diameter of the protruding end. In this way, the wire retaining ring 2 is engaged in the second groove when it is first fitted, and the wire retaining ring is in a non-expanded state, which makes it easy to engage in the first groove when the piston rod is pushed in. In another preferred embodiment, the diameter of the wire retaining ring 2 is equal to the maximum diameter of the protruding end. The wire retaining ring 2 does not need to be expanded when it is fitted. Compared with the above-mentioned wire retaining ring 2 structure, the thickness of the wire retaining ring 2 needs to be greater than the above-mentioned wire retaining ring 2 thickness, so as to engage in the first groove and the second groove.

[0025] The installation process in this embodiment is as follows: First, the wire retaining ring 2 is fitted onto the outer periphery of the protruding end. Due to the elastic structure of the wire retaining ring 2, when it is snapped onto the surface of the protruding end, the inner part of the wire retaining ring 2 quickly enters the entrance area of ​​the second groove. However, at this time, the wire retaining ring 2 is in an unexpanded state, thus only achieving preliminary positioning. Then, the piston 3 is pushed along the first chamfer 5 and gradually inserted into the inner cavity of the piston rod 1 in the axial direction. As the protruding end gradually enters the interior of the piston rod 1, the wire retaining ring 2 contacts the inner wall of the piston rod 1 under the guidance of the second chamfer 6 and is subjected to... Radial compression causes the wire retaining ring 2 to gradually press into the second groove and slide radially. As the piston 3 continues to move forward, the wire retaining ring 2 is forced into the first groove, thus releasing space. The outer side of the wire retaining ring 2 eventually enters the first groove of the piston rod 1, and the inner side enters the second groove of the protruding end. The wire retaining ring 2 then returns to its original position, achieving a double-groove engagement. As the wire retaining ring 2 falls completely into the relative area of ​​the two grooves, an axial anti-reverse structure is formed between the protruding end and the piston rod 1, thereby securing the piston 3 firmly inside the piston rod 1 and preventing any relative axial displacement.

[0026] After installation, the piston 3 and piston rod 1 reciprocate inside the cylinder 4. The piston end bears the hydraulic action and transmits the pressure to the piston rod 1. The embedded structure of the wire retaining ring 2 between the first and second grooves ensures a firm connection and will not loosen due to reciprocating impact or hydraulic pulsation. At the same time, the clearance fit structure allows for a certain small deviation, further avoiding the risk of bending caused by lateral loads and improving the operational stability and life of the entire hydraulic cylinder.

[0027] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A piston rod and piston embedded structure for a forklift lifting cylinder, characterized in that, include: Piston component (3), including a protruding end and a piston end; Piston rod (1), the piston rod (1) is connected to piston (3), the inner wall of the piston rod (1) is provided with a first groove, and the outer wall of the protruding end is provided with a second groove corresponding to the first groove; A wire retaining ring (2) is engaged between the first groove and the second groove, and the piston rod (1) and the piston component (3) are connected by the wire retaining ring (2); a second chamfer (6) is provided at the end face of the piston rod (1). The cylinder (4) and the piston (3) drive the piston rod (1) to reciprocate in the cylinder (4).

2. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The piston (3) and piston rod (1) are in clearance fit.

3. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The wire retaining ring (2) is made of elastic steel wire and has an open ring structure.

4. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The diameter of the wire retaining ring (2) is greater than the maximum diameter of the protruding end.

5. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The diameter of the wire retaining ring (2) is equal to the maximum diameter of the protruding end.

6. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The protruding end is integrally formed with the piston end.

7. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The first groove and the second groove are arranged opposite each other in the axial direction.

8. The piston rod and piston embedded structure for a forklift lifting cylinder according to claim 1, characterized in that, The protruding end is provided with a first chamfer (5).

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