Bidirectional piston balance valve structure and gas spring

Abstract

The utility model relates to the technical field of springs, in particular to a two-way piston balance valve structure and a gas spring, and aims to solve the problem that an existing two-way piston balance valve structure occupies a large axial space. The bidirectional piston balance valve structure comprises a cylinder barrel and a valve element, the valve element is inserted into the cylinder barrel and is in sliding connection with the cylinder barrel, and a first cavity and a second cavity are formed in the two ends of the valve element respectively; the valve element comprises a piston assembly, a sliding sleeve, a first reset spring, a sliding shaft and a second reset spring. The sliding sleeve is sleeved on the piston assembly and is in sliding connection with the piston assembly. The sliding shaft is inserted into the piston assembly and is in sliding connection with the piston assembly. According to the bidirectional piston balance valve structure provided by the utility model, the two symmetrically arranged valve cores are changed into the valve core sharing the piston assembly, and the axial size of the valve core is shortened while the bidirectional residence at any position is realized through the matching of the sliding sleeve and the first reset spring and the matching of the sliding shaft and the second reset spring; and the occupation of the axial space is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of springs, in particular to a two-way piston balance valve structure and a gas spring. Background Art

[0002] An ordinary gas spring can only stop the lifted object at the end of the stroke and cannot retain the lifted object at any position except the dead zone according to needs. When applied, it is impossible to stop structures such as doors at any angle, and the usability is poor. The existing two-way piston balance valve structure can achieve retention at any position when the piston rod moves in both directions. However, due to the arrangement of two symmetrically arranged valve cores, the axial space occupied by the valve cores is relatively large, resulting in an increase in the length of the gas spring. Content of the Utility Model

[0003] The purpose of the utility model is to provide a two-way piston balance valve structure and a gas spring to improve the problem that the existing two-way piston balance valve structure occupies a relatively large axial space.

[0004] To solve the above technical problems, the technical solution provided by the utility model is as follows:

[0005] A two-way piston balance valve structure includes a cylinder barrel and a valve core. The valve core is inserted into the cylinder barrel and is slidably connected to the cylinder barrel. The two ends of the valve core are respectively a first chamber and a second chamber;

[0006] The valve core includes a piston assembly, a sliding sleeve, a first return spring, a sliding shaft and a second return spring; the sliding sleeve is sleeved on the piston assembly and is slidably connected to the piston assembly, and the sliding shaft is inserted into the piston assembly and is slidably connected to the piston assembly;

[0007] The piston assembly is provided with a first passage and a second passage. The two ends of the first passage are respectively communicated with the first chamber and the second chamber, and the two ends of the second passage are respectively communicated with the first chamber and the second chamber;

[0008] The first return spring is used to apply an elastic force to the sliding sleeve so that the sliding sleeve abuts against the piston assembly and the first passage is blocked, and the second return spring is used to apply an elastic force to the sliding shaft so that the second passage is blocked;

[0009] When the valve core moves towards the first chamber, the medium pressure in the first chamber is higher than the medium pressure in the second chamber, and then the sliding sleeve is pushed to overcome the elastic force of the first return spring so that the first passage is communicated;

[0010] When the valve core moves towards the second chamber, the medium pressure in the second chamber is higher than the medium pressure in the first chamber, and then the sliding shaft is pushed to overcome the elastic force of the second return spring so that the second passage is communicated.

[0011] Further, a communication cavity, a first radial hole, and a second radial hole are provided on the piston assembly; the communication cavity is provided with a communication port communicating with the first cavity, and the sliding shaft is inserted into the communication cavity to block the communication port; a radial communication hole is provided on the sliding sleeve;

[0012] The first passage includes the first radial hole, the communication cavity, the second radial hole, and the radial communication hole that are sequentially communicated. At this time, the first radial hole communicates with the first cavity, and the radial communication hole communicates with the second cavity; the second passage includes the communication port, the communication cavity, and the first radial hole that are sequentially communicated. At this time, the communication port communicates with the first cavity, and the first radial hole communicates with the second cavity.

[0013] Further, the valve core further includes a first sealing ring, the first sealing ring is sleeved on the piston assembly, and the piston assembly and the sliding sleeve enclose a first annular groove for installing the first sealing ring;

[0014] When the first passage is communicated, the first sealing ring abuts against the sliding sleeve to block the annular gap between the sliding sleeve and the cylinder barrel; when the second passage is communicated, the first sealing ring abuts against the piston assembly to block the annular gap between the piston assembly and the cylinder barrel.

[0015] Further, in the structure of the two-way piston balance valve, the valve core further includes a second sealing ring, the second sealing ring is sleeved on the piston assembly and inserted into the sliding sleeve;

[0016] The two second sealing rings are arranged on both sides of the radial communication hole to cut off the communication between the second radial hole and the radial communication hole.

[0017] Further, the valve core further includes a first retaining sleeve, one end of the first return spring abuts against the first retaining sleeve, and the other end abuts against the sliding sleeve.

[0018] Further, the piston assembly includes a piston body and a second retaining sleeve, the second retaining sleeve is inserted into the piston body and encloses a communication cavity with the piston body, and the sliding shaft is inserted into the second retaining sleeve to block the communication cavity;

[0019] One end of the second return spring abuts against the second retaining sleeve, and the other end abuts against the sliding shaft.

[0020] Further, the valve core further includes a piston rod, the piston rod is inserted into the piston body and connected to the piston body;

[0021] The inner hole of the second sleeve is the communication port, and the sliding shaft is arranged as a variable-diameter shaft and inserted into the communication port to close and open the communication port.

[0022] In another aspect of the present invention, a gas spring is proposed, which includes the above-mentioned two-way piston balance valve structure.

[0023] Furthermore, the gas spring further includes an isolation piston, and the isolation piston is inserted into the cylinder barrel and slidably connected to the cylinder barrel;

[0024] Between the isolation piston and the valve core is a rodless cavity, one end of the valve core away from the rodless cavity is a rod cavity, and one end of the isolation piston away from the rodless cavity is a pressure cavity;

[0025] The pressure cavity, the rod cavity and the rodless cavity are all filled with a medium.

[0026] Furthermore, the inner wall of the cylinder barrel is provided with a communication groove extending axially, and the communication groove is used to communicate the first cavity and the second cavity.

[0027] Combining the above technical solutions, the technical effects that the present invention can achieve are as follows:

[0028] The two-way piston balance valve structure provided by the present invention includes a cylinder barrel and a valve core. The valve core is inserted into the cylinder barrel and slidably connected to the cylinder barrel. The two ends of the valve core are respectively a first cavity and a second cavity; the valve core includes a piston assembly, a sliding sleeve, a first return spring, a sliding shaft and a second return spring; the sliding sleeve is sleeved on the piston assembly and slidably connected to the piston assembly, and the sliding shaft is inserted into the piston assembly and slidably connected to the piston assembly; the piston assembly is provided with a first passage and a second passage. Both ends of the first passage are communicated with the first cavity and the second cavity respectively, and both ends of the second passage are communicated with the first cavity and the second cavity respectively; the first return spring is used to apply an elastic force to the sliding sleeve so that the sliding sleeve abuts against the piston assembly and blocks the first passage, and the second return spring is used to apply an elastic force to the sliding shaft so that the second passage is blocked; when the valve core moves towards the first cavity, the medium pressure in the first cavity is higher than the medium pressure in the second cavity, and then the sliding sleeve is pushed to overcome the elastic force of the first return spring to connect the first passage; when the valve core moves towards the second cavity, the medium pressure in the second cavity is higher than the medium pressure in the first cavity, and then the sliding shaft is pushed to overcome the elastic force of the second return spring to connect the second passage.

[0029] The two-way piston balance valve structure provided by the present invention changes two symmetrically arranged valve cores into one valve core with a common piston assembly. While realizing two-way arbitrary position retention through the cooperation of the sliding sleeve and the first return spring, and the cooperation of the sliding shaft and the second return spring, the axial dimension of the valve core is shortened, and the occupation of the axial space is reduced. Description of the Drawings

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 Schematic diagram of the structure of the two-way piston balance valve provided by the embodiment of the present invention;

[0032] Figure 2 For Figure 1 The enlarged view of part A in

[0033] Figure 3 Schematic diagram of the structure during compression;

[0034] Figure 4 Schematic diagram of the structure during stretching;

[0035] Figure 5 Schematic diagram of the structure of the gas spring.

[0036] Icon: 10, cylinder barrel; 20, valve core; 30, first chamber; 40, second chamber; 50, isolation piston; 100, piston assembly; 200, sliding sleeve; 300, first return spring; 400, sliding shaft; 500, second return spring; 600, first sealing ring; 700, second sealing ring;

[0037] 800, first retaining sleeve; 900, piston rod; 1000, fifth sealing ring; 1100, limiting ring;

[0038] 110, piston body; 120, second retaining sleeve; 130, retaining ring; 140, third sealing ring;

[0039] 150, fourth sealing ring; 111, communication chamber; 112, first radial hole; 113, second radial hole; 210, radial communication hole; 201, first annular groove. Specific embodiments

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the accompanying drawings here can be arranged and designed in various different configurations.

[0041] Accordingly, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts fall within the scope of protection of the present invention.

[0042] The following will describe in detail some embodiments of the present invention with reference to the drawings. Without conflict, the following embodiments and the features in the embodiments may be combined with each other.

[0043] The existing two-way piston balance valve structure can achieve dwelling at any position when the piston rod moves bidirectionally. However, due to the arrangement of two symmetrically arranged valve cores, the axial space occupied by the valve cores is relatively large, resulting in an increase in the length of the gas spring.

[0044] In view of this, the present invention provides a two-way piston balance valve structure, including a cylinder barrel 10 and a valve core 20. The valve core 20 is inserted into the cylinder barrel 10 and is slidably connected to the cylinder barrel 10. The two ends of the valve core 20 are respectively a first chamber 30 and a second chamber 40. The valve core 20 includes a piston assembly 100, a sliding sleeve 200, a first return spring 300, a sliding shaft 400, and a second return spring 500. The sliding sleeve 200 is sleeved on the piston assembly 100 and is slidably connected to the piston assembly 100. The sliding shaft 400 is inserted into the piston assembly 100 and is slidably connected to the piston assembly 100. The piston assembly 100 is provided with a first passage and a second passage. The two ends of the first passage are respectively communicated with the first chamber 30 and the second chamber 40, and the two ends of the second passage are respectively communicated with the first chamber 30 and the second chamber 40. The first return spring 300 is used to apply an elastic force to the sliding sleeve 200 so that the sliding sleeve 200 abuts against the piston assembly 100 and the first passage is blocked. The second return spring 500 is used to apply an elastic force to the sliding shaft 400 so that the second passage is blocked. When the valve core 20 moves towards the first chamber 30, the medium pressure in the first chamber 30 is higher than the medium pressure in the second chamber 40, thereby pushing the sliding sleeve 200 and overcoming the elastic force of the first return spring 300 to connect the first passage. When the valve core 20 moves towards the second chamber 40, the medium pressure in the second chamber 40 is higher than the medium pressure in the first chamber 30, thereby pushing the sliding shaft 400 and overcoming the elastic force of the second return spring 500 to connect the second passage.

[0045] The two-way piston balance valve structure provided by the present invention changes the two symmetrically arranged valve cores 20 into a valve core 20 sharing a piston assembly 100. While achieving dwelling at any bidirectional position through the cooperation of the sliding sleeve 200 and the first return spring 300, and the cooperation of the sliding shaft 400 and the second return spring 500, the axial dimension of the valve core 20 is shortened, and the occupation of the axial space is reduced.

[0046] The following will be combined withFigures 1 - 5 The structure and shape of the two-way piston balance valve structure provided in this embodiment will be described in detail:

[0047] In an alternative solution of this embodiment, the two-way piston balance valve structure further includes a first sealing ring 600, a second sealing ring 700, a first retaining sleeve 800, a piston rod 900, a fifth sealing ring 1000, and a limit ring 1100; the piston assembly 100 includes a piston body 110, a second retaining sleeve 120, a retaining ring 130, a third sealing ring 140, and a fourth sealing ring 150, as Figure 2 shown.

[0048] Specifically, the piston body 110 is provided with a hole penetrating along its own axial direction. The second retaining sleeve 120 and the piston rod 900 are respectively inserted into the piston body 110 from both ends of the piston body 110 and enclose a communication cavity 111 with the piston body 110. The inner hole of the second retaining sleeve 120 is set as a communication port. One end of the communication port is communicated with the first cavity 30, and the other end is communicated with the communication cavity 111. The sliding shaft 400 is inserted into the second retaining sleeve 120 to block the communication port, thereby cutting off the communication state between the communication cavity 111 and the first cavity 30.

[0049] In this embodiment, a step is provided on the inner wall of the piston body 110. The second retaining sleeve 120 abuts against the step. The retaining ring 130 is arranged at one end of the second retaining sleeve 120 away from the step for fixing the second retaining sleeve 120 to prevent its axial displacement. The retaining ring 130 and the piston body 110 can be connected by means such as threaded connection, welding, and press-fitting. The third sealing ring 140 is installed in the groove at the end of the second retaining sleeve 120 for sealing the annular gap between the second retaining sleeve 120 and the sliding shaft 400. The retaining ring 130, the second retaining sleeve 120, and the sliding shaft 400 enclose an annular groove for installing the third sealing ring 140. The fourth sealing ring 150 is sleeved on the second retaining sleeve 120 and installed in the annular groove formed by the second retaining sleeve 120 and the piston body 110 for sealing the annular gap between the second retaining sleeve 120 and the piston body 110.

[0050] In this embodiment, the fifth sealing ring 1000 is sleeved on the piston rod 900 and inserted into the piston body 110. Specifically, the fifth sealing ring 1000 is snap-fitted into the annular groove provided on the piston rod 900 to seal the annular gap between the piston rod 900 and the piston body 110.

[0051] In this embodiment, one end of the second return spring 500 abuts against the second retaining sleeve 120, and the other end abuts against the sliding shaft 400, for applying a thrust force to the sliding shaft 400 so that the sliding shaft 400 abuts against the end of the piston rod 900. The first retaining sleeve 800 is sleeved on the piston body 110 and the piston rod 900; one end of the first return spring 300 abuts against the first retaining sleeve 800, and the other end abuts against the sliding sleeve 200, for applying a thrust force to the sliding sleeve 200 so that the sliding sleeve 200 abuts against the piston body 110. The limit ring 1100 is arranged at one end of the first retaining sleeve 800 away from the first return spring 300, for restricting the axial displacement of the first retaining sleeve 800. Specifically, the limit ring 1100 is clamped in the annular groove formed on the piston rod 900.

[0052] In this embodiment, a first radial hole 112 and a second radial hole 113 that communicate with the communication cavity 111 are further arranged on the piston body 110; the communication cavity 111 communicates with the first cavity 30 through a communication port, the sliding shaft 400 is inserted into the communication cavity 111 to block the communication port, and a radial communication hole 210 is arranged on the sliding sleeve 200, as Figure 2 , Figure 3 shown.

[0053] In this embodiment, the first sealing ring 600 is sleeved on the piston body 110 and abuts against the inner wall of the cylinder barrel 10, and a first annular groove 201 is formed between the piston body 110 and the sliding sleeve 200 for installing the first sealing ring 600. When the first passage is communicated, the first sealing ring 600 abuts against the sliding sleeve 200 to block the annular gap between the sliding sleeve 200 and the cylinder barrel 10, as Figure 3 shown; when the second passage is communicated, the first sealing ring 600 abuts against the piston assembly 100 to block the annular gap between the piston assembly 100 and the cylinder barrel 10, as Figure 4 shown.

[0054] Specifically, the first passage includes the first radial hole 112, the communication cavity 111, the second radial hole 113, and the radial communication hole 210 that are sequentially communicated, as Figure 3 shown. At this time, the first radial hole 112 communicates with the first cavity 30 through the annular gap between the piston body 110 and the cylinder barrel 10, and the radial communication hole 210 communicates with the second cavity 40 through the annular gap between the sliding sleeve 200 and the cylinder barrel 10; the second passage includes the communication port, the communication cavity 111, and the first radial hole 112 that are sequentially communicated. At this time, the communication port communicates with the first cavity 30, and the first radial hole 112 communicates with the second cavity 40 through the annular gap between the sliding sleeve 200 and the cylinder barrel 10.

[0055] In this embodiment, the second sealing ring 700 is sleeved on the piston assembly 100 and inserted into the sliding sleeve 200; two second sealing rings 700 are arranged on both sides of the radially communicating hole 210 to cut off the communication between the second radial hole 113 and the radially communicating hole 210. Specifically, the second sealing ring 700 can be installed on the piston body 110 or the sliding sleeve 200, and an annular groove or an axially extending communicating groove can be formed on the inner wall of the sliding sleeve 200 to increase the communication cross-sectional area between the radially communicating hole 210 and the second radial hole 113.

[0056] In this embodiment, the sliding shaft 400 is arranged as a variable-diameter shaft and inserted into the communication port to realize the closing and opening of the communication port. Specifically, an annular boss is arranged on the sliding shaft 400 for abutting against the second return spring 500. The sliding shaft 400 is divided into a large-diameter section and a small-diameter section. When the large-diameter section cooperates with the third sealing ring 140, the communication hole is closed. When the small-diameter section cooperates with the third sealing ring 140, the communication port is opened. Further, to improve the reliability of opening, a communicating groove extending along the axis is arranged on the small-diameter section to increase the flow cross-sectional area. To ensure the smooth movement of the sliding shaft 400, a transition section is also arranged between the large-diameter section and the small-diameter section to prevent the stepped shaft from affecting the movement. When the transition section cooperates with the third sealing ring 140, the communication port starts to open.

[0057] The working process of the two-way piston balance valve structure provided in this embodiment is as follows:

[0058] In the initial state, the first chamber 30 and the second chamber 40 are communicated through the annular gap between the cylinder barrel 10 and the valve core 20 to achieve the pressure balance between the two, as Figure 2 shown.

[0059] When the piston rod 900 is pushed by an external force to move the valve core 20 towards the first chamber 30, the first sealing ring 600 is kept stationary by the frictional resistance of the inner wall of the cylinder barrel 10 and thus approaches the end of the sliding sleeve 200. The first sealing ring 600 presses the sliding sleeve 200 and seals the annular gap between the sliding sleeve 200 and the cylinder barrel 10, so that the first chamber 30 and the second chamber 40 are separated by the valve core 20 and the two chambers are no longer communicated. As the space of the first chamber 30 decreases and the space of the second chamber 40 increases, a pressure difference is generated.

[0060] As the pressure difference increases, the first sealing ring 600 pushes the sliding sleeve 200 to move rightward to compress the first return spring 300. As the communicating groove on the inner wall of the sliding sleeve 200 passes over the second sealing ring 700, the second radial hole 113 is communicated with the radially communicating hole 210, as Figure 3As shown in the figure. The media in the first chamber 30 and the second chamber 40 are connected through the annular gap between the piston body 110 and the cylinder barrel 10, the first annular groove 201, the first radial hole 112, the communication chamber 111, the second radial hole 113 and the radial communication hole 210 in sequence. The pressure difference between the two chambers remains basically unchanged, and the resistance to the movement of the valve core 20 remains basically unchanged. That is, the first return spring 300 generates a tendency to push the sliding sleeve 200 to move to the left. This tendency will generate a tendency to compress the space of the first chamber 30 and increase the space of the second chamber 40, thereby generating a pressure difference between the first chamber 30 and the second chamber 40. This pressure difference acts on the sliding sleeve 200 and balances the elastic force of the first return spring 300 to prevent the communication between the first chamber 30 and the second chamber 40 from being cut off due to the reset of the sliding sleeve 200.

[0061] At the same time, this pressure difference acts on the inner cross-section of the cylinder barrel 10 to generate an external compressive force, so as to balance the load and produce the effect of staying at any position. After the valve core 20 moves to the required position, removing the external force to stop pushing the valve core 20 can achieve stopping at any position.

[0062] When the external force pushes the valve core 20 to move towards the second chamber 40, the first sealing ring 600 is kept stationary by the frictional resistance of the inner wall of the cylinder barrel 10 and approaches the step of the piston body 110. The first sealing ring 600 presses the piston body 110 and seals the annular gap between the piston body 110 and the cylinder barrel 10, so that the first chamber 30 and the second chamber 40 are separated by the valve core 20 and the two chambers are no longer connected. As the space of the first chamber 30 increases and the space of the second chamber 40 decreases, a pressure difference is generated. At this time, the second chamber 40 is connected to the communication chamber 111 through the annular gap between the sliding sleeve 200 and the cylinder barrel 10, the first annular groove 201 and the first radial hole 112 in sequence.

[0063] As the pressure difference increases, the pressure acts on the large diameter section and the transition section of the sliding shaft 400, thereby pushing the sliding shaft 400 to overcome the thrust of the second return spring 500 and compress the second return spring 500. When the transition section of the sliding shaft 400 cooperates with the third sealing ring 140, the communication chamber 111 is connected to the first chamber 30, so as to realize the communication between the first chamber 30 and the second chamber 40, as Figure 3 shown. The second return spring 500 generates a tendency to push the sliding shaft 400 to move to the right. This tendency will generate a tendency to compress the second space and increase the space of the first chamber 30, thereby generating a pressure difference between the first chamber 30 and the second chamber 40. This pressure difference acts on the sliding shaft 400 and balances the elastic force of the second return spring 500 to prevent the communication between the first chamber 30 and the second chamber 40 from being cut off due to the reset of the sliding shaft 400.

[0064] Meanwhile, this pressure difference acts on the inner cross-section of the cylinder barrel 10 to generate an external compressive force, thereby balancing the load and achieving the effect of staying at any position. After the spool 20 moves to the desired position, the external force is removed to stop pushing the spool 20, thus realizing the stop at any position.

[0065] Based on the two-way piston balance valve structure provided in this embodiment, a gas spring is proposed, which includes the above two-way piston balance valve structure and also includes an isolation piston 50. The isolation piston 50 is inserted into the cylinder barrel 10 and is slidably connected to the cylinder barrel 10. Specifically, as Figure 1 shown, the cavity between the isolation piston 50 and the spool 20 is the rodless cavity, the end of the spool 20 away from the rodless cavity is the rod cavity, and the end of the isolation piston 50 away from the rodless cavity is the pressure cavity. The pressure cavity, the rod cavity, and the rodless cavity are all filled with a medium, such as nitrogen, oil-gas mixture, hydraulic oil, etc. Among them, the media in the rod cavity and the rodless cavity are the same.

[0066] In this embodiment, a communication groove extending axially is provided on the inner wall of the cylinder barrel 10. The communication groove is used to communicate the first chamber 30 and the second chamber 40. When the spool 20 is located at the communication groove, the first chamber 30 and the second chamber 40 are always communicated by the communication groove and will not be blocked by the spool 20. The gas spring generates a thrust through the cross-sectional area difference between the rod cavity and the rodless cavity, so that the effect of staying at any position is not generated. Specifically, multiple sections of communication grooves can be arranged at intervals along the axial direction of the cylinder barrel 10 to realize the segmented opening of the gas spring. At this time, the piston rod 900 can move a certain distance by itself in the section covered by the communication groove. After leaving the area covered by the communication groove, the two-way piston balance valve structure comes into effect and the spool 20 stops moving. If further movement is required, additional force needs to be applied, thus realizing segmented stop.

[0067] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-way piston balancing valve structure, characterized in that: It comprises a cylinder (10) and a valve core (20), wherein the valve core (20) is inserted into the cylinder (10) and is slidably connected to the cylinder (10), and the two ends of the valve core (20) are respectively a first cavity (30) and a second cavity (40); The valve core (20) comprises a piston assembly (100), a sliding sleeve (200), a first return spring (300), a sliding shaft (400) and a second return spring (500); the sliding sleeve (200) is sleeved on the piston assembly (100) and is slidably connected to the piston assembly (100); the sliding shaft (400) is inserted into the piston assembly (100) and is slidably connected to the piston assembly (100); The piston assembly (100) is provided with a first passage and a second passage, wherein two ends of the first passage are respectively communicated with the first chamber (30) and the second chamber (40), and two ends of the second passage are respectively communicated with the first chamber (30) and the second chamber (40); The first return spring (300) is used to apply an elastic force to the sliding sleeve (200) so that the sliding sleeve (200) abuts against the piston assembly (100) and blocks the first passage, and the second return spring (500) is used to apply an elastic force to the sliding shaft (400) so that the second passage is blocked; When the valve core (20) moves toward the first chamber (30), the medium pressure in the first chamber (30) is higher than the medium pressure in the second chamber (40), thereby pushing the sliding sleeve (200) and overcoming the elastic force of the first return spring (300) to connect the first passage; When the valve core (20) moves toward the second chamber (40), the medium pressure in the second chamber (40) is higher than the medium pressure in the first chamber (30), thereby pushing the sliding shaft (400) and overcoming the elastic force of the second return spring (500) to connect the second passage.

2. The bidirectional piston balancing valve structure according to claim 1 is characterized in that: The piston assembly (100) is provided with a communication cavity (111), a first radial hole (112) and a second radial hole (113); the communication cavity (111) is provided with a communication port communicating with the first cavity (30), and the sliding shaft (400) is inserted into the communication cavity (111) to block the communication port; the sliding sleeve (200) is provided with a radial communication hole (210); The first passage comprises the first radial hole (112), the connecting cavity (111), the second radial hole (113), and the radial connecting hole (210) which are connected in sequence. At this time, the first radial hole (112) is connected to the first cavity (30), and the radial connecting hole (210) is connected to the second cavity (40); the second passage comprises the connecting port, the connecting cavity (111), and the first radial hole (112) which are connected in sequence. At this time, the connecting port is connected to the first cavity (30), and the first radial hole (112) is connected to the second cavity (40).

3. The bidirectional piston balancing valve structure according to claim 2 is characterized in that: The valve core (20) further comprises a first sealing ring (600), wherein the first sealing ring (600) is sleeved on the piston assembly (100), and the piston assembly (100) and the sliding sleeve (200) form a first annular groove (201) for mounting the first sealing ring (600); When the first passage is connected, the first sealing ring (600) abuts against the sliding sleeve (200) to seal the annular gap between the sliding sleeve (200) and the cylinder (10); when the second passage is connected, the first sealing ring (600) abuts against the piston assembly (100) to seal the annular gap between the piston assembly (100) and the cylinder (10).

4. The bidirectional piston balancing valve structure according to claim 3 is characterized in that: The valve core (20) further comprises a second sealing ring (700), wherein the second sealing ring (700) is sleeved on the piston assembly (100) and inserted into the sliding sleeve (200); Two second sealing rings (700) are arranged on both sides of the radial communication hole (210) to cut off the communication between the second radial hole (113) and the radial communication hole (210).

5. The bidirectional piston balancing valve structure according to claim 4 is characterized in that: The valve core (20) further comprises a first stop sleeve (800); one end of the first return spring (300) abuts against the first stop sleeve (800), and the other end abuts against the sliding sleeve (200).

6. The bidirectional piston balancing valve structure according to claim 5, characterized in that: The piston assembly (100) comprises a piston body (110) and a second stopper sleeve (120); the second stopper sleeve (120) is inserted into the piston body (110) and forms a communicating cavity (111) with the piston body (110); the sliding shaft (400) is inserted into the second stopper sleeve (120) to block the communicating cavity (111); One end of the second return spring (500) abuts against the second stop sleeve (120), and the other end abuts against the sliding shaft (400).

7. The bidirectional piston balancing valve structure according to claim 6, characterized in that: The valve core (20) further comprises a piston rod (900), wherein the piston rod (900) is inserted into the piston body (110) and connected to the piston body (110); The inner hole of the second stop sleeve (120) is the communication port, and the sliding shaft (400) is configured as a variable diameter shaft and is inserted into the communication port to achieve closing and opening of the communication port.

8. A gas spring, characterized in that: It comprises a bidirectional piston balancing valve structure as described in any one of claims 1-7.

9. The gas spring according to claim 8, characterized in that It also includes an isolation piston (50), wherein the isolation piston (50) is inserted into the cylinder barrel (10) and is slidably connected to the cylinder barrel (10); A rodless cavity is formed between the isolation piston (50) and the valve core (20), an end of the valve core (20) away from the rodless cavity is a rod cavity, and an end of the isolation piston (50) away from the rodless cavity is a pressure cavity; The pressure chamber, the rod chamber and the rodless chamber are all filled with medium.

10. The gas spring according to claim 8, characterized in that The inner wall of the cylinder (10) is provided with a communication groove extending in the axial direction, and the communication groove is used to connect the first chamber (30) and the second chamber (40).

Images