Oil cylinder piston locking device

Abstract

The utility model provides an oil cylinder piston locking device which comprises a piston rod and a piston, the piston is in threaded connection with one end of the piston rod, and the oil cylinder piston locking device is characterized in that a rectangular ring groove is formed in the end of the piston rod, and the circle center of the rectangular ring groove and the circle center of the section of the piston rod are eccentrically arranged; a threaded hole is formed in the piston in the radial direction of the piston rod, a set screw is arranged in the threaded hole, and the inner end of the set screw is held in the rectangular ring groove. Before the oil cylinder piston anti-loosening device is assembled, the rectangular ring groove is machined in the piston rod in advance, the situation of secondary machining after assembly is avoided, the situation that a hydraulic system is polluted by scrap iron generated by remachining after assembly is avoided, and the oil cylinder piston anti-loosening effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic cylinder pistons, and more specifically, to a hydraulic cylinder piston anti-loosening device. Background Technology

[0002] Currently, most hydraulic cylinder pistons are connected to the piston rod via threads, and are secured with two radially cylindrical set screws. The set screws are installed by machining set screw holes in the piston after assembly, drilling blind holes in the piston rod, and finally tightening the set screws. This assembly method presents two problems: First, the metal shavings generated during blind hole drilling are difficult to clean completely, potentially clogging the hydraulic system or scratching the cylinder seals during operation. Second, the diameter of the machined blind holes is generally larger than the diameter of the set screws, rendering the set screws ineffective in preventing loosening.

[0003] For example, utility model patent CN221628552U discloses a hydraulic cylinder piston anti-loosening structure, including a hydraulic cylinder piston, a shaft retaining ring, a set screw, and a piston rod. The hydraulic cylinder piston and piston rod are threadedly connected, and a through threaded hole is provided along the radial direction of the hydraulic cylinder piston. The set screw is placed in the threaded hole, and the end of the set screw contacts the piston rod. The shaft retaining ring is clamped at the tail of the set screw, forming an anti-loosening structure composed of the set screw and the shaft retaining ring. The piston rod has a groove, and the end of the set screw is pressed into the groove. This hydraulic cylinder piston anti-loosening structure does not require punching points, does not damage the piston body structure, and has the characteristics of compact overall structure and convenient installation and adjustment. However, the disclosed structure of this hydraulic cylinder piston anti-loosening structure still uses the method of machining a groove on the piston rod to fix the set screw, which does not avoid the contamination of iron filings. Utility Model Content

[0004] To solve the problem of iron filings contamination and improve the anti-loosening effect of hydraulic cylinder pistons, the technical solution adopted by this utility model is: a hydraulic cylinder piston anti-loosening device, including a piston rod and a piston, wherein the piston is threadedly connected to one end of the piston rod, and a rectangular annular groove is provided at the end of the piston rod, and the center of the rectangular annular groove is eccentrically set with respect to the center of the cross-section of the piston rod.

[0005] The piston has a threaded hole along the radial direction of the piston rod, and a set screw is provided in the threaded hole. The inner end of the set screw is held in the rectangular annular groove.

[0006] Based on the above, the threaded hole is provided correspondingly to the rectangular annular groove.

[0007] Based on the above, in order to improve the holding force, the piston is provided with at least one pair of threaded holes, and the set screws are respectively provided in the threaded holes.

[0008] Based on the above, the piston is provided with a pair of threaded holes, and each of the threaded holes is provided with a set screw, with the pair of set screws arranged vertically in relation to each other.

[0009] Based on the above, in order to ensure that at least one set screw will tighten more and more when a loosening trend occurs, the groove depth values ​​of the rectangular annular grooves located at each of the threaded holes are different.

[0010] Based on the above, the end of the piston rod is provided with an external thread to form a piston threaded portion, and the diameter of the piston rod decreases in a stepwise manner from the piston threaded portion to the rectangular annular groove.

[0011] Based on the above, in order to achieve countersunk installation of the set screw, the threaded hole is a countersunk threaded hole.

[0012] Based on the above, the set screw is a flat-head set screw, the inner end of which is held in the rectangular annular groove, and the flat-head set screw is in contact with the side wall of the rectangular annular groove to prevent the piston from shaking along the piston rod axis.

[0013] This utility model has substantial features and advancements compared to existing technologies. Specifically, the utility model provides a hydraulic cylinder piston anti-loosening device. By providing external threads on the piston rod to form a threaded portion, the piston can be detachably mounted on the piston rod through threaded engagement with the piston rod. Simultaneously, by creating a rectangular annular groove on the piston rod, the set screw is fitted into this groove, ensuring that the set screw head is properly seated within it. The side of the rectangular annular groove holds the set screw in place, guaranteeing an anti-loosening effect. More importantly, the rectangular annular groove on the piston rod is pre-machined before assembly, eliminating the need for post-assembly machining and preventing metal shavings from contaminating the hydraulic system.

[0014] Furthermore, by arranging a pair of set screws evenly along the piston circumference and setting the rectangular annular groove eccentrically to the piston thread, when a loosening tendency occurs, at least one set screw will tighten more and more, thereby improving the anti-loosening effect. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of a hydraulic cylinder piston anti-loosening device provided by this utility model.

[0016] Figure 2 This is a schematic diagram of the end structure of an anti-loosening device for a hydraulic cylinder piston provided by this utility model.

[0017] In the diagram: 1. Piston rod; 2. Piston; 3. Piston threaded section; 4. Upper threaded hole; 5. Upper set screw; 6. Lower set screw; 7. Lower threaded hole; 8. Rectangular annular groove; 9. Piston rod head. Detailed Implementation

[0018] The technical solution of this utility model will be further described in detail below through specific embodiments.

[0019] Example 1

[0020] This embodiment provides a hydraulic cylinder piston anti-loosening device, such as... Figure 1 , Figure 2 As shown, the device includes a piston rod 1 and a piston 2, with the piston 2 threadedly connected to one end of the piston rod 1. A rectangular annular groove 8 is provided at the end of the piston rod 1, and the center of the rectangular annular groove 8 is eccentrically located to the center of the cross-section of the piston rod 1. Specifically, the end where the piston is located can be referred to as the piston rod head 9.

[0021] The piston 2 has a threaded hole along the radial direction of the piston rod 1, and a set screw is provided in the threaded hole. The inner end of the set screw is held in the rectangular annular groove 8.

[0022] Specifically, the threaded hole is correspondingly provided with the rectangular annular groove. To improve the holding force, a pair of threaded holes are provided on the piston, and a set screw is provided in each of the threaded holes, with the pair of set screws arranged vertically corresponding to each other.

[0023] Based on their location, a pair of threaded holes can be designated as upper threaded hole 4 and lower threaded hole 7. A pair of set screws can be designated as upper set screw 5 and lower set screw 6.

[0024] The piston rod has an external thread at its end, forming a piston threaded portion 3. The diameter of the piston rod decreases in a stepped manner from the piston threaded portion to the rectangular annular groove.

[0025] Example 2

[0026] This embodiment provides a hydraulic cylinder piston anti-loosening device. The main difference from Embodiment 1 is that, in this embodiment, in order to ensure that at least one set screw will tighten more and more when a loosening trend occurs, the groove depth values ​​of the rectangular annular grooves located at each of the threaded holes are different along the radial direction of the piston rod 1.

[0027] Example 3

[0028] This embodiment provides a hydraulic cylinder piston anti-loosening device. The main difference from Embodiment 1 is that, in this embodiment, in order to achieve countersunk installation of the set screw, the threaded hole is a countersunk threaded hole.

[0029] Example 4

[0030] This embodiment provides a hydraulic cylinder piston anti-loosening device. The main difference from Embodiment 1 is that in this embodiment, the set screw is a flat-head set screw. The inner end of the flat-head set screw is held in the rectangular annular groove, and the flat-head set screw is in contact with the side wall of the rectangular annular groove to prevent the piston from shaking along the piston rod axis.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A hydraulic cylinder piston anti-loosening device, comprising a piston rod and a piston, wherein the piston is threadedly connected to one end of the piston rod, characterized in that: The piston rod has a rectangular annular groove at its end, and the center of the rectangular annular groove is eccentrically located to the center of the cross-section of the piston rod. The piston has a threaded hole along the radial direction of the piston rod, and a set screw is provided in the threaded hole. The inner end of the set screw is held in the rectangular annular groove.

2. The hydraulic cylinder piston anti-loosening device according to claim 1, characterized in that: The threaded hole is provided in correspondence with the rectangular annular groove.

3. The hydraulic cylinder piston anti-loosening device according to claim 1, characterized in that: The piston has at least one pair of threaded holes, and each threaded hole contains a set screw.

4. The hydraulic cylinder piston anti-loosening device according to claim 1, characterized in that: The piston has a pair of threaded holes, and a set screw is respectively installed in the threaded holes. The pair of set screws are arranged vertically and vertically.

5. A hydraulic cylinder piston anti-loosening device according to claim 3 or 4, characterized in that: The groove depth values ​​of the rectangular annular grooves located at each of the threaded holes are different.

6. A hydraulic cylinder piston anti-loosening device according to claim 1, 2, 3, or 4, characterized in that: The piston rod has an external thread at its end, forming a piston threaded portion. The diameter of the piston rod decreases in a stepped manner from the piston threaded portion to the rectangular annular groove.

7. The hydraulic cylinder piston anti-loosening device according to claim 6, characterized in that: The threaded hole is a countersunk threaded hole.

8. The hydraulic cylinder piston anti-loosening device according to claim 7, characterized in that: The set screw is a flat-head set screw, the inner end of which is held in the rectangular annular groove, and the flat-head set screw is in contact with the side wall of the rectangular annular groove to prevent the piston from shaking along the piston rod axis.

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