Double-piston lockable gas spring

Abstract

The utility model provides a double-piston lockable gas spring, which belongs to the technical field of gas springs and comprises a cylinder barrel, a first piston and a second piston are arranged in the cylinder barrel, the ends of the first piston and the second piston are fixed, a rod cavity and a rodless cavity are formed by the two pistons, extending edges extend from the peripheries of the two pistons, and a second flow cavity is formed by the two extending edges. The first piston forms a first flow cavity through the extending edge, the valve rod is inserted into the middle of the first piston, the middle of the valve rod is concaved inwards to form a piston flow channel, and the piston flow channel is communicated with the first flow cavity. A control rod used for jacking up the valve rod to communicate the piston runner with the rodless cavity is arranged in the piston rod, the head end of the control rod abuts against the tail end of the valve rod, the tail end of the control rod extends out of the tail end of the piston rod, and pressing is convenient to achieve control. Axial displacement of the two pistons is achieved based on the pressure difference between the rod cavity and the rodless cavity, double-flow-channel control is formed through the arrangement of the through hole and the gap, and the problem of high resistance of low-flow and low-speed products is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas springs, and particularly relates to a double-piston type lockable gas spring. Background Technique

[0002] A gas spring is a general component. In a conventional lockable gas spring, since the pistons move in oil, during the movement process, the two chambers are connected through an opening valve rod and then the movement occurs, and it stops after closing. Since the size of the flow rate in this process has only one channel, it is impossible to separately control the flow rates during compression and extension, resulting in the inability to control the flow rate bidirectionally, and further leading to the problem of high resistance in low-flow and low-speed products. Content of the Utility Model

[0003] The purpose of the utility model is to provide a double-piston type lockable gas spring, which is characterized in that it includes a cylinder barrel, the two ends of the cylinder barrel are sealed, and a piston rod is inserted into its tail end. A control rod is arranged inside the piston rod, and both ends of the control rod extend out of the two ends of the piston rod. Among them, the head end of the control rod is clamped with the head end of the piston rod;

[0004] A first piston and a second piston fixed to each other through their ends are arranged inside the cylinder barrel. Both pistons are provided with through holes in the middle. The second piston is arranged on the outer periphery of the end of the piston rod. A valve rod is inserted in the middle of the first piston. The tail end of the valve rod abuts against the head end of the control rod. The head end of the valve rod is clamped on the head end surface of the first piston and is sealed. A rod chamber and a rodless chamber are formed inside the cylinder barrel through the first piston and the second piston. The rod chamber is located below the second piston, and the rodless chamber is located between the second piston and the plug;

[0005] First extensions, second extensions and third extensions respectively extend outwards from the outer periphery of the head end of the first piston, the head end and the tail end of the second piston. The outer peripheries of the first extension and the third extension are both in contact with the inner wall of the cylinder barrel. A gap is formed between the second extension and the inner wall of the cylinder barrel. A first flow chamber is formed below the first extension, a second flow chamber is formed between the second extension and the third extension. The third extension is provided with an annular through hole communicating the second flow chamber and the rod chamber. The second extension is provided with a first through hole communicating the second flow chamber and the first flow chamber. The outer periphery of the middle part of the valve rod is concavely arranged to form a piston flow channel with the inner wall of the middle part of the first piston. A second through hole communicating the first flow chamber and the piston flow channel is also arranged in the middle part of the first piston. When the control rod jacks up the valve rod, the rodless chamber, the piston flow channel, the first flow chamber, the gap, the first through hole, the second flow chamber, the annular through hole and the rod chamber are communicated with each other;

[0006] An O-ring for blocking the gap is also arranged inside the second flow chamber.

[0007] Furthermore, when the control rod jacks up the valve rod, the first piston and the second piston perform axial displacement based on the pressure difference between the rod chamber and the rodless chamber;

[0008] When the first piston and the second piston move towards the rodless cavity, the gap communicates with the second flow cavity; when the first piston and the second piston move towards the rod cavity, the O-ring blocks the gap.

[0009] Furthermore, a first counterbore is provided inwardly at the head end of the piston rod, a fourth circumferential extension extends outwardly from the outer periphery of the head end of the control rod, and the control rod is clamped in the first counterbore through the fourth circumferential extension.

[0010] A second counterbore is provided at the head end of the first piston, a fifth circumferential extension extends from the outer periphery of the head end of the valve rod, and the valve rod abuts against the bottom surface of the counterbore through the bottom surface of the fifth circumferential extension.

[0011] Furthermore, O-rings for sealing are provided on the inner circumference of the first counterbore, at the position where the middle through-hole of the first piston is close to the second counterbore, on the outer periphery of the first circumferential extension, and on the inner circumference of the head end of the second piston.

[0012] Furthermore, a guide sleeve is provided. The guide sleeve is located inside the tail end of the cylinder barrel and is provided on the outer periphery of the piston rod. A W-ring for sealing is also provided at the head end of the guide sleeve, and the W-ring is provided on the outer periphery of the piston rod.

[0013] Furthermore, a limit groove for restricting the moving stroke of the piston is provided between the piston and the W-ring, and the limit groove is integrally provided with the inner wall of the cylinder.

[0014] An O-ring for realizing the seal between the through-hole in the middle and the piston rod is fixed at the tail end of the second piston.

[0015] Compared with the prior art, the beneficial effects of the present utility model are mainly reflected in that the present utility model forms a dual-flow control by setting a dual-piston form, and solves the problem of high resistance of low-flow and low-speed products. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. is a schematic structural diagram of a dual-piston type lockable gas spring of the present utility model when it is about to move in the compression direction.

[0017] Figure 2 is Figure 1 a partially enlarged flow direction schematic diagram of the medium flowing from the rodless cavity to the rod cavity during compression in FIG.

[0018] Figure 3 FIG. is a schematic structural diagram of a dual-piston type lockable gas spring of the present utility model when it is about to move in the extension direction.

[0019] Figure 4 is Figure 3 a partially enlarged flow direction schematic diagram of the medium flowing from the rod cavity to the rodless cavity during extension in FIG.

[0020] Among them, 1. cylinder barrel; 2. plug; 3. guide sleeve; 4. W-ring; 5. piston rod; 6. control rod; 7. first piston; 8. second piston; 9. valve rod; 10. O-ring; 11. partition plate; 12. rodless cavity; 13. rod chamber; 14. first flow chamber; 15. second flow chamber; 16. piston flow channel; 17. annular through hole; 18. first through hole; 19. gap; 20. second through hole. Detailed implementation

[0021] The following will describe in more detail a double-piston lockable gas spring of the present invention with reference to the schematic diagram, which shows the preferred embodiments of the present invention. It should be understood that those skilled in the art can modify the present invention described herein while still achieving the advantageous effects of the present invention. Therefore, the following description should be understood as a broad guidance for those skilled in the art and not as a limitation to the present invention.

[0022] As Figure 1 shown, a double-piston lockable gas spring includes a cylinder barrel 1. Plug 2 and a mutually cooperating W-shaped sealing ring and guide sleeve 3 are respectively arranged at both ends of the cylinder barrel 1 to achieve sealing. Among them, the guide sleeve 3 and the W-shaped sealing ring are both arranged inside the tail end of the cylinder barrel 1 and are arranged on the outer periphery of the piston rod 5 inserted into the cylinder barrel 1.

[0023] Two pistons are also arranged inside the cylinder barrel 1, namely the first piston 7 and the second piston 8. The two pistons are fixedly connected to each other at the ends. The first piston 7 is close to the plug 2, and the second piston 8 is close to the W-ring 4. The middle parts of both pistons are provided with through holes and are interconnected. Among them, the second piston 8 is arranged on the outer periphery of the head end of the piston rod 5. A valve rod 9 is arranged in the middle of the first piston 7. The head end of the valve rod 9 extends outwards with a circumferential edge, which is clamped inside the counterbore arranged in the middle of the head end of the first piston 7 through the circumferential edge. The tail end of the valve rod 9 passes through the first piston 7 and extends into the piston rod 5, and abuts against the head end of the control rod 6 preset inside the piston rod 5. Similarly, the head end of the control rod 6 is provided with a circumferential edge outwards, and a counterbore is arranged in the middle of the head end of the piston rod 5. The control rod 6 is limited in the counterbore at the head end of the piston rod 5 through the circumferential edge. The tail end of the control rod 6 extends out of the tail end of the piston rod 5. By pressing the tail end of the control rod 6, the head end of the control rod 6 can lift the valve rod 9, so that the circumferential edge at the head end of the valve rod 9 is away from the counterbore.

[0024] On the outer periphery of the head end of the first piston 7, and on the outer peripheries of the head end and the tail end of the second piston 8, there are outwardly extending flanges. Among them, the flange at the head end of the first piston 7 and the flange at the tail end of the second piston 8 are both in contact with the inner wall of the cylinder barrel 1. The flange at the head end of the second piston 8 is arranged close to the inner wall of the cylinder barrel 1, leaving a gap 19. In the utility model, a rodless cavity 12 and a rod cavity 13 are formed inside the cylinder barrel 1 by the first piston 7 and the second piston 8. Among them, the rodless cavity 12 is located between the first piston 7 and the plug 2, and the rod cavity 13 is located between the second piston 8 and the W-shaped ring 4. Specifically, a limiting groove 11 is also provided inside the cylinder barrel 1. The limiting groove 11 is integrally arranged with the inner wall of the cylinder barrel 1 and is used to limit the stroke of the second piston 8 moving towards the W-shaped ring 4. Among them, an O-ring is fixedly arranged in the middle of the tail end of the second piston 8. The O-ring is fixed at the end of the tail end of the second piston 8 and is used to realize the seal between the inner wall of the second piston 8 and the piston rod 5.

[0025] A first flow cavity 14 is formed between the flange at the head end of the first piston 7 and the flange at the head end of the second piston 8. A second flow cavity 15 is formed between the flanges at both ends of the second piston 8. The outer periphery in the middle of the valve rod 9 is recessed, and a piston flow channel 16 is formed on the inner periphery of the through hole in the middle of the first piston 7. A second through hole 20 for communicating the first flow cavity 14 and the piston flow channel 16 is provided inside the first piston 7. A second through hole 20 for communicating the first flow cavity 14 and the second flow cavity 15 is provided at the head end flange of the second piston 8. The first flow cavity 14 and the second flow cavity 15 are also communicated through the gap 19. A ring-shaped through hole is also provided at the tail end flange of the second piston 8 for communicating the second flow cavity 15 and the rod cavity 13.

[0026] In order to achieve sealing, O-rings are provided on the inner periphery of the counterbore of the first piston 7, on the outer periphery of the head end flange, on the inner periphery of the second counterbore, on the inner periphery of the internal through hole of the second piston 8, and at the bottom of the tail end flange.

[0027] When the control rod 6 does not lift the valve rod 9, the bottom of the flange at the head end of the valve rod 9 abuts against the O-ring, realizing the disconnection between the rodless cavity 12 and the piston flow channel 16, and further realizing the seal.

[0028] When the control rod 6 lifts the valve rod 9, the bottom of the flange at the head end of the valve rod 9 moves away from the O-ring and is not sealed. The rodless cavity 12 is communicated with the piston flow channel 16 and the first flow cavity 14, and further the rodless cavity 12 is communicated with the rod cavity 13, so that the first piston 7 and the second piston 8 perform axial displacement based on the pressure difference between the rod cavity 13 and the rodless cavity 12.

[0029] An O-ring 10 is provided in the second flow chamber 15. The O-ring 10 does not block the first through-hole 18, and its outer diameter is the same as the inner diameter of the cylinder barrel 1. When a movement in the compression direction is required, after the valve rod 9 is lifted, the pressure difference between the rod chamber 13 and the rodless chamber 12 drives the first piston 7 and the second piston 8 to move towards the plug 2. This O-ring 10 does not block the gap 19, and the medium flows from the rodless chamber 12 through the counterbore of the first piston 7, the piston flow channel 16, the second through-hole 20, the first flow chamber 14, the first through-hole 18 and the gap 19, the second flow chamber 15, and the annular through-hole 17 to the rod chamber 13.

[0030] When a movement in the extension direction is required, after the valve rod 9 is lifted, when the pressure difference between the rod chamber 13 and the rodless chamber 12 drives the first piston 7 and the second piston 8 to move towards the partition 11, this O-ring 10 blocks the gap 19, and the medium in the rod chamber 13 flows through the annular through-hole 17, the second flow chamber 15, the first through-hole 18, the first flow chamber 14, the second through-hole 20, the piston flow channel 16 and the counterbore of the first piston 7 to the rodless chamber 12 in sequence.

[0031] The present utility model realizes opening the communication switch between the piston flow channel 16 and the rodless chamber 12 by squeezing the tail end of the control rod 6 extending from the bottom end of the piston rod 5, realizes the communication between the rodless chamber 12 and the rod chamber 13, thereby causing the displacement of the first piston 7 and the second piston 8, and finally realizes the locking function of the gas spring.

[0032] The present utility model forms two flow channels through the setting of the gap 19, and realizes the separate control of the flow rates during compression and extension through the setting of the O-ring 10, thereby realizing the two-way control of the flow rate and solving the problem of high resistance of low-flow and low-speed products.

[0033] The above is only the preferred embodiment of the present utility model and does not impose any limitation on the present utility model. Any person skilled in the art within the technical field, without departing from the technical solution of the present utility model, any equivalent replacement or modification and other changes made to the technical solution and technical content disclosed by the present utility model are all within the content of the technical solution of the present utility model and still belong to the protection scope of the present utility model.

Claims

1. A double-piston lockable gas spring, characterized in that: It comprises a cylinder, both ends of which are sealed, and a piston rod is inserted into the rear end of the cylinder, a control rod is arranged inside the piston rod, and both ends of the control rod extend out of the two ends of the piston rod, wherein the head end of the control rod is clamped with the head end of the piston rod; The cylinder is provided with a first piston and a second piston fixed to each other through the ends, and both pistons are provided with a central through-hole, the second piston is provided at the outer periphery of the end of the piston rod, a valve rod is inserted in the middle of the first piston, the tail end of the valve rod abuts against the head end of the control rod, the head end of the valve rod is clamped on the head end surface of the first piston and is sealed, and a rod chamber and a rodless chamber are formed in the cylinder through the first piston and the second piston, the rod chamber is located below the second piston, and the rodless chamber is located between the second piston and the plug; The outer periphery of the head end of the first piston, the outer periphery of the head end and the tail end of the second piston respectively extend outward with a first extension, a second extension and a third extension, the outer peripheries of the first extension and the third extension are both in contact with the inner wall of the cylinder, a gap is formed between the second extension and the inner wall of the cylinder, a first flow chamber is formed below the first extension, and a second flow chamber is formed between the second extension and the third extension, the third extension is provided with an annular through hole connecting the second flow chamber and the rod chamber, the second extension is provided with a first through hole connecting the second flow chamber and the first flow chamber, the outer periphery of the middle part of the valve rod is concavely arranged and a piston flow channel is formed on the inner wall of the middle part of the first piston, the middle part of the first piston is also provided with a second through hole connecting the first flow chamber and the piston flow channel, when the control rod lifts the valve rod, the rodless chamber, the piston flow channel, the first flow chamber, the gap, the first through hole, the second flow chamber, the annular through hole and the rod chamber are connected to each other; An O-ring for blocking the gap is also arranged inside the second flow cavity.

2. The double-piston lockable gas spring according to claim 1, characterized in that: When the control rod lifts the valve rod, the first piston and the second piston are axially displaced based on the pressure difference between the rod chamber and the rodless chamber; When the first piston and the second piston move toward the rodless chamber, the gap is communicated with the second flow chamber; when the first piston and the second piston move toward the rod chamber, the O-ring blocks the gap.

3. The double-piston lockable gas spring according to claim 1, characterized in that: A first countersunk hole is provided inwardly at the head end of the piston rod, a fourth edge is extended outwardly from the outer periphery of the head end of the control rod, and the control rod is clamped in the first countersunk hole through the fourth edge; A second countersunk hole is disposed at the head end of the first piston, a fifth extended edge extends from the periphery of the head end of the valve rod, and the valve rod abuts against the bottom surface of the countersunk hole through the bottom surface of the fifth extended edge.

4. The double-piston lockable gas spring according to claim 3, characterized in that: The inner periphery of the first counterbore, the through hole in the first piston close to the second counterbore, the outer periphery of the first edge and the inner periphery of the first end of the second piston are all provided with O-rings for sealing.

5. The double-piston lockable gas spring according to claim 1, characterized in that: A guide sleeve is also provided, which is located inside the rear end of the cylinder and arranged on the periphery of the piston rod. A W-shaped ring for sealing is also provided at the front end of the guide sleeve, and the W-shaped ring is arranged on the periphery of the piston rod.

6. The double-piston lockable gas spring according to claim 5, characterized in that: A limiting groove for limiting the piston's travel is also provided between the piston and the W-shaped ring, and the limiting groove is integrally provided with the inner wall of the cylinder; An O-ring is fixed to the tail end of the second piston for sealing between the through-hole and the piston rod.

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