Stepless limiting stopper and automobile

Abstract

The utility model relates to the technical field of limiters, in particular to a stepless limiter and an automobile, and aims at solving the problem that an existing stepless limiter is long in starting stroke. The stepless limiter comprises a cylinder barrel, a switch valve, a piston rod and an isolation piston, the switch valve, the piston rod and the isolation piston are inserted into the cylinder barrel, the piston rod is connected with the switch valve, a second cavity is formed between the switch valve and the isolation piston, one end, away from the isolation piston, of the switch valve is a first cavity, and one end, away from the switch valve, of the isolation piston is a pressurizing cavity. The isolation piston is arranged to divide the original second cavity into the pressurization cavity, back pressure is provided through pressure provided by the pressurization cavity, when the switch valve moves towards the direction of the isolation piston, the opening pressure of the switch valve can be achieved only by moving the switch valve by a small stroke, and therefore the first cavity and the second cavity can be rapidly communicated, vacuum of the first cavity is avoided, and the service life of the switch valve is prolonged. The problem that a stepless limiting stopper needs a long stroke to be started is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of limiters, in particular to a stepless limiter and a car. Background Art

[0002] In side-opening doors and horizontal tailgates, stepless stoppers can stop the door at any position during opening and closing. After leaving the stop position, the door opens and closes smoothly with minimal resistance. However, existing stepless stoppers suffer from insufficient actuation pressure, resulting in a long actuation stroke and creating a vacuum in the rod chamber, which affects the stepless stopper's timely response. Utility Model Content

[0003] The purpose of the utility model is to provide a stepless limiter and a car, so as to solve the problem that the existing stepless limiter has a long starting stroke.

[0004] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0005] A stepless limiter comprises a cylinder and a switch valve, a piston rod and an isolation piston inserted in the cylinder, wherein the piston rod is connected to the switch valve, a second chamber is formed between the switch valve and the isolation piston, an end of the switch valve away from the isolation piston is a first chamber, and an end of the isolation piston away from the switch valve is a pressurizing chamber;

[0006] The switch valve comprises a valve sleeve, a first valve core assembly and a second valve core assembly, wherein the first valve core assembly and the second valve core assembly are respectively inserted into the valve sleeve from both ends of the valve sleeve;

[0007] When the switch valve moves toward the first chamber, the medium pressure in the first chamber increases and drives the first valve core assembly to start, thereby connecting the first chamber and the second chamber;

[0008] When the switch valve moves toward the second chamber, the medium pressure in the second chamber increases and drives the second valve core assembly to start, thereby communicating the first chamber with the second chamber.

[0009] Furthermore, the boosting chamber is filled with nitrogen and / or a boosting spring is provided, and the nitrogen and the boosting spring are used to apply a thrust to the isolation piston so that the isolation piston squeezes the second chamber.

[0010] Furthermore, the first valve core assembly and the second valve core assembly are symmetrical in structure and symmetrically arranged on both sides of the valve sleeve; the end of the first valve core assembly away from the second valve core assembly is a first cavity, and the end of the second valve core assembly away from the first valve core assembly is a second cavity;

[0011] The first valve core assembly includes a sliding sleeve unit, a return spring, and a fixed unit. One end of the sliding sleeve unit is inserted into the valve sleeve, and the other end is sleeved on the fixed unit. The return spring is used to apply elastic force to the sliding sleeve unit to make the sliding sleeve unit abut against the fixed unit.

[0012] When the switch valve moves toward the first chamber, the medium pressure in the first chamber increases and overcomes the elastic force of the return spring of the first valve core assembly to push the sliding sleeve unit away from the fixed unit, thereby connecting the first chamber and the second chamber;

[0013] When the switch valve moves toward the second chamber, the medium pressure in the second chamber increases and overcomes the elastic force of the return spring of the second valve core assembly to push the sliding sleeve unit away from the fixed unit, thereby connecting the first chamber and the second chamber.

[0014] Furthermore, the fixing unit includes a first connecting ring and a second connecting ring, and the sliding sleeve unit includes a sliding sleeve body, one end of the sliding sleeve body is inserted into the valve sleeve, and the other end is sleeved on the first connecting ring to form a first annular gap with the first connecting ring; the switch valve and the cylinder barrel form a first pressure chamber;

[0015] The first connecting ring is provided with a first axial hole, and the second connecting ring is provided with a second axial hole. The first pressure chamber, the first annular gap, the first axial hole, and the second axial hole are connected in sequence. The end of the second axial hole away from the first axial hole is connected to the first chamber or the second chamber.

[0016] The sliding sleeve unit abuts against the first connecting ring to block the first axial hole.

[0017] Furthermore, the sliding sleeve unit further comprises a sealing ring, which is inserted into the sliding sleeve body, with one end of the sealing ring abutting against the sliding sleeve body and the other end abutting against the first connecting ring;

[0018] The sealing ring is provided with a truncated cone-shaped protrusion, which is inserted into the first axial hole and has a diameter that gradually increases along a direction of exiting the first axial hole.

[0019] Furthermore, the sliding sleeve unit is provided with a first damping hole and a leakage hole, and the sliding sleeve unit and the valve sleeve form a second pressure chamber;

[0020] One end of the first damping hole is communicated with the first pressure chamber, and the other end is communicated with the second pressure chamber; one end of the leakage hole is communicated with the first pressure chamber, and the other end is communicated with the first axial hole.

[0021] Furthermore, the first valve core assembly further includes a first sealing ring, which is sleeved on the fixing unit and inserted into the cylinder, and is used to seal the annular gap between the fixing unit and the cylinder;

[0022] When the medium pressure in the first pressure chamber increases, the medium can flow from the first pressure chamber into the first chamber or the second chamber through the first sealing ring.

[0023] Furthermore, the stepless limiter further includes a guide member, which is disposed in the first cavity and connected to the switch valve;

[0024] The guide member includes a damping assembly, which includes a damping seat and a damping core. The damping core can move along its own axis and is inserted into the damping seat, thereby forming a first damping chamber with the damping seat and a second damping chamber with the switch valve.

[0025] The damping seat is provided with a second damping hole, and the first damping cavity, the second damping hole and the second damping cavity are connected in sequence;

[0026] A first communicating groove is provided on the outer side of the damping seat, and the first communicating groove is used to connect the second damping hole and the second damping cavity.

[0027] Optionally, the stepless limiter further includes a guide member, which is disposed in the first cavity and connected to the switch valve;

[0028] The guide member includes a damping assembly, which includes a damping seat and a damping core. The damping core can move along its own axis and is inserted into the damping seat, thereby forming a first damping chamber with the damping seat and a second damping chamber with the switch valve.

[0029] The inner wall of the damping seat is provided with a damping groove, and the first damping cavity, the damping groove and the second damping cavity are connected in sequence.

[0030] Another aspect of the present invention provides an automobile comprising the above-mentioned stepless limiter.

[0031] Based on the above technical solutions, the technical effects achieved by the present invention are:

[0032] The stepless limiter provided by the utility model includes a cylinder and a switch valve, a piston rod and an isolation piston inserted in the cylinder, the piston rod is connected to the switch valve, and a second chamber is formed between the switch valve and the isolation piston. The end of the switch valve away from the isolation piston is the first chamber, and the end of the isolation piston away from the switch valve is the boosting chamber; the switch valve includes a valve sleeve, a first valve core assembly and a second valve core assembly, and the first valve core assembly and the second valve core assembly are respectively inserted into the valve sleeve from both ends of the valve sleeve; when the switch valve moves toward the first chamber, the medium pressure in the first chamber increases and drives the first valve core assembly to start, thereby connecting the first chamber and the second chamber; when the switch valve moves toward the second chamber, the medium pressure in the second chamber increases and drives the second valve core assembly to start, thereby connecting the first chamber and the second chamber.

[0033] The stepless limiter provided by the present invention separates the original second chamber into a boost chamber by providing an isolation piston, and uses the pressure provided by the boost chamber to provide back pressure. When the switch valve moves toward the isolation piston, only a small movement stroke is required to reach the opening pressure of the switch valve, thereby quickly connecting the first chamber and the second chamber, avoiding the formation of a vacuum in the first chamber. This avoids the problem of the stepless limiter requiring a long stroke to start, avoids the problem of a vacuum in the first chamber, i.e., the rod chamber, and improves the response speed of the stepless limiter. In addition, when the switch valve moves away from the isolation piston, the pressure in the boost chamber can push the isolation piston toward the second chamber, thereby avoiding the formation of a vacuum in the second chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 A schematic structural diagram of a stepless limiter provided in an embodiment of the present utility model;

[0036] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0037] Figure 3 for Figure 1 Enlarged view of point B in the middle;

[0038] Figure 4 A three-dimensional diagram of a stepless limiter provided in an embodiment of the present utility model;

[0039] Figure 5 Schematic diagram of the structure of the sleeve body;

[0040] Figure 6Schematic diagram of the structure of the sealing ring;

[0041] Figure 7 is a structural diagram of the first connecting ring;

[0042] Figure 8 is a structural schematic diagram of the second connecting ring;

[0043] Figure 9 Schematic diagram of the structure of the damping core.

[0044] Icons: 10, cylinder; 20, switch valve; 30, piston rod; 40, isolation piston; 50, guide; 100, valve sleeve; 200, first valve core assembly; 300, second valve core assembly; 400, damping assembly; 500, sealing assembly; 600, rod body; 700, connecting assembly; 800, connecting rod; 900, first baffle; 210, sliding sleeve unit; 220, return spring; 230, fixing unit; 240, first sealing ring; 211, sliding sleeve body; 212, sealing ring; 2111, first damping hole; 2112, drain hole; 2121, truncated cone protrusion; 2113, guide protrusion; 231, first connecting ring; 232, Second connecting ring; 233, limiting ring; 234, sealing sleeve; 2311, first axial hole; 2312, guide groove; 2321, second axial hole; 410, damping seat; 420, damping core; 430, choke; 510, stop sleeve; 520, second sealing ring; 710, first connecting sleeve; 720, second connecting sleeve; 730, first mounting ring; 740, second mounting ring; 101, first chamber; 102, second chamber; 103, boost chamber; 201, first pressure chamber; 202, first annular gap; 203, second pressure chamber; 401, first damping chamber; 402, second damping chamber; 403, second damping hole; 404, damping groove. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0046] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0047] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0048] The existing stepless limiter has insufficient starting pressure, which leads to a long starting stroke and generates vacuum in the rod chamber, affecting the timely response of the stepless limiter.

[0049] In view of this, the utility model provides a stepless limiter, including a cylinder 10 and a switch valve 20, a piston rod 30 and an isolation piston 40 inserted in the cylinder 10, the piston rod 30 is connected to the switch valve 20, a second chamber 102 is formed between the switch valve 20 and the isolation piston 40, the end of the switch valve 20 away from the isolation piston 40 is a first chamber 101, and the end of the isolation piston 40 away from the switch valve 20 is a boost chamber 103; the switch valve 20 includes a valve sleeve 100, a first valve core assembly 200 and a second valve core assembly 300. 00, the first valve core assembly 200 and the second valve core assembly 300 are respectively inserted into the valve sleeve 100 from both ends of the valve sleeve 100; when the switch valve 20 moves toward the first chamber 101, the medium pressure in the first chamber 101 increases and drives the first valve core assembly 200 to start, thereby connecting the first chamber 101 and the second chamber 102; when the switch valve 20 moves toward the second chamber 102, the medium pressure in the second chamber 102 increases and drives the second valve core assembly 300 to start, thereby connecting the first chamber 101 and the second chamber 102.

[0050] The stepless limiter provided by the present invention separates the original second chamber 102 into a boost chamber 103 by providing an isolation piston 40, and uses the pressure provided by the boost chamber 103 to provide back pressure. When the switch valve 20 moves toward the isolation piston 40, only a small movement stroke is required to reach the opening pressure of the switch valve 20, thereby quickly connecting the first chamber 101 and the second chamber 102, avoiding the formation of a vacuum in the first chamber 101. Therefore, the problem of the stepless limiter requiring a long stroke to start is avoided, and the problem of a vacuum in the first chamber 101, i.e., the rod chamber, is avoided, thereby improving the response speed of the stepless limiter. In addition, when the switch valve 20 moves in a direction away from the isolation piston 40, the pressure in the boost chamber 103 can push the isolation piston 40 to move toward the second chamber 102, thereby avoiding the formation of a vacuum in the second chamber 102.

[0051] The following combination Figures 1-9 The structure and shape of the stepless limiter provided in this embodiment are described in detail:

[0052] In this embodiment, the stepless limiter includes a cylinder 10 and a switch valve 20, a piston rod 30, an isolation piston 40 and a guide member 50 inserted in the cylinder 10. Figure 1As shown, the piston rod 30 is connected to the switch valve 20 and the guide member 50. A second chamber 102 is formed between the switch valve 20 and the isolation piston 40. The end of the switch valve 20 away from the isolation piston 40 is the first chamber 101. The end of the isolation piston 40 away from the switch valve 20 is the boost chamber 103. In other words, the second chamber 102 is a rodless chamber, and the first chamber 101 is a rod-mounted chamber.

[0053] In this embodiment, the switch valve 20 includes a valve sleeve 100, a first valve core assembly 200, a second valve core assembly 300 and a first sealing ring 240. The first valve core assembly 200 and the second valve core assembly 300 are structurally symmetrical and are symmetrically arranged on both sides of the valve sleeve 100; the end of the first valve core assembly 200 away from the second valve core assembly 300 is a first chamber 101, and the end of the second valve core assembly 300 away from the first valve core assembly 200 is a second chamber 102; the switch valve 20 and the cylinder 10 form a first pressure chamber 201.

[0054] Taking the second valve core assembly 300 as an example for structural description, the second valve core assembly 300 includes a sleeve unit 210, a return spring 220 and a fixed unit 230. The sleeve unit 210 includes a sleeve body 211 and a sealing ring 212. The fixed unit 230 includes a limit ring 233, a first connecting ring 231, a second connecting ring 232 and a sealing sleeve 234. Figure 2 As shown, one end of the return spring 220 abuts the sleeve body 211, and the other end abuts the valve sleeve 100, thereby pressing the sleeve unit 210 against the fixed unit 230. Specifically, a partition is provided in the middle of the valve sleeve 100 to separate the inner bore of the valve sleeve 100 into two independent accommodating chambers, each of which accommodates the two sleeve units 210. A retaining ring 233 is inserted between the sleeve body 211 and the valve sleeve 100, and the sleeve body 211 is inserted into the accommodating chamber of the valve sleeve 100, thereby enclosing the second pressure chamber 203 with the valve sleeve 100, the retaining ring 233, and the sleeve body 211.

[0055] In this embodiment, one end of the limiting ring 233 abuts the valve sleeve 100, and the other end abuts the first connecting ring 231. The end of the first connecting ring 231, away from the limiting ring 233, abuts the second connecting ring 232. The sealing sleeve 234 is sleeved onto the second connecting ring 232 and inserted into the first connecting ring 231. The sealing sleeve 234 defines an annular groove on its outer side and is fitted with a sealing ring to seal the annular gap between the sealing sleeve 234 and the first connecting ring 231. The first connecting ring 231, the sealing sleeve 234, and the second connecting ring 232 form an annular groove for mounting a first sealing ring 240. The first sealing ring 240 is sleeved onto the fixing unit 230 and inserted into the cylinder 10 to seal the annular gap between the fixing unit 230 and the cylinder 10. The two first sealing rings 240 seal the annular gaps between the first valve core assembly 200, the second valve core assembly 300, and the cylinder 10, thereby forming a first pressure chamber 201 enclosed by the on-off valve 20 and the cylinder 10. When the medium pressure in the first pressure chamber 201 increases, the medium can flow from the first pressure chamber 201 into the first chamber 101 or the second chamber 102 through the first sealing ring 240. In this embodiment, the first sealing ring 240 can be a Y-shaped sealing ring to facilitate one-way opening.

[0056] In this embodiment, the sealing ring 212 is inserted into the end of the sleeve body 211 away from the valve sleeve 100. Figure 2 、 Figure 6 、 Figure 7 As shown, a truncated cone-shaped protrusion 2121 is provided on the end of the sealing ring 212 away from the sleeve body 211. A first axial hole 2311 is provided on the first connecting ring 231. The truncated cone-shaped protrusion 2121 is inserted into the first axial hole 2311 and its diameter gradually increases as it exits the first axial hole 2311. As the truncated cone-shaped protrusion 2121 exits the first axial hole 2311, the flow cross-section gradually increases, thereby gradually reducing the pressure difference between the two sides, which promotes smooth operation and reduces shock.

[0057] In this embodiment, the inner wall of the sleeve body 211 is provided with a guide protrusion 2113 extending along the axial direction, and the first connecting ring 231 is provided with a corresponding guide groove 2312 extending along the axial direction. The guide protrusion 2113 is engaged and slidably connected with the guide groove 2312 to prevent the sleeve body 211 and the first connecting ring 231 from relative rotation, thereby ensuring the cooperation between the conical protrusion 2121 and the first axial hole 2311.

[0058] In this embodiment, the sleeve body 211 and the first connecting ring 231 form a first annular gap 202. The sleeve body 211 is provided with a first damping hole 2111 and a drain hole 2112. One end of the first damping hole 2111 communicates with the first pressure chamber 201, and the other end communicates with the second pressure chamber 203. The first connecting ring 231 is provided with a first axial hole 2311, and the second connecting ring 232 is provided with a second axial hole 2321. The first pressure chamber 201, the first annular gap 202, the first axial hole 2311, and the second axial hole 2321 are sequentially connected. The end of the second axial hole 2321, remote from the first axial hole 2311, communicates with the first chamber 101 or the second chamber 102. The drain hole 2112 is connected to the first axial hole 2311 at one end and to the first pressure chamber 201 at the other end. During low-speed operation, liquid flows out of the drain hole 2112, preventing back pressure from forming.

[0059] In this embodiment, the sleeve body 211 is inserted into the outer side of the valve sleeve 100 and is installed with a sealing ring. The outer circular surface of the limiting ring 233 that cooperates with the sleeve body 211 is installed with a sealing ring. The sealing ring is set according to the sealing requirements to ensure the correct flow direction of the medium.

[0060] In this embodiment, the guide member 50 is disposed in the first cavity 101 and includes a damping assembly 400 and a sealing assembly 500. The damping assembly 400 includes a damping seat 410, a damping core 420 and a choke 430. Figure 3 As shown, the damping seat 410 is inserted into and connected to the cylinder 10. The damping core 420 can move along its own axis and be inserted into the damping seat 410, thereby forming a first damping chamber 401 with the damping seat 410 and a second damping chamber 402 with the switch valve 20. The damping seat 410 is provided with a second damping hole 403, and the first damping chamber 401, the second damping hole 403, and the second damping chamber 402 are sequentially connected. The flow blocker 430 is mounted on the damping core 420 and installed in an annular groove outside the damping core 420. The damping core 420 is used to seal the annular gap between the damping seat 410 and the damping core 420. Specifically, the flow blocker 430 is made of wear-resistant plastic and is floatingly installed in the annular groove outside the damping core 420 to achieve reliable sealing. A sealing ring is installed on the outer wall of the damping seat 410 to seal the annular gap between the damping seat 410 and the cylinder 10. The sealing ring is a static seal.

[0061] In this embodiment, a first communicating groove is provided on the outer side of the damping seat 410 , and the first communicating groove is used to connect the second damping hole 403 and the second damping cavity 402 .

[0062] Optionally, the inner wall of the damping seat 410 is provided with a damping groove 404, interconnecting the first damping chamber 401, the damping groove 404, and the second damping chamber 402 in sequence. Specifically, the cross-sectional size of the damping groove 404 can be adjusted to suit different loads, and the cross-sectional area of ​​the damping groove 404 can be configured to gradually change for smoother operation. The flow control ring 430 forms an interference fit with the inner wall of the damping seat 410, ensuring that the medium is discharged only through the second damping hole 403 or the damping groove 404, thereby providing damping. Either the second damping hole 403 or the damping groove 404 can be used.

[0063] In this embodiment, the sealing assembly 500 includes a baffle 510 and a second sealing ring 520, which is mounted on the baffle 510. The baffle 510 is inserted into the end of the damping seat 410 away from the damping core 420 and forms an annular groove with the damping core 420 for mounting the second sealing ring 520. The piston rod 30 is inserted into the guide member 50, thereby sealing the annular gap between the piston rod 30, the baffle 510, and the damping seat 410 via the second sealing ring 520 to prevent medium leakage. The second sealing ring 520 is configured as a dynamic seal.

[0064] In this embodiment, the piston rod 30 includes a rod body 600, a connecting assembly 700, a connecting rod 800 and a first baffle 900. Figure 2 、 Figure 3 As shown, the rod body 600 is sequentially inserted into the stopper sleeve 510, the second sealing ring 520, the damping seat 410, and the damping core 420, and is slidably connected to the stopper sleeve 510, the second sealing ring 520, and the damping seat 410. The connecting assembly 700 is used to connect the rod body 600 and the connecting rod 800. The connecting rod 800 is sequentially inserted into the second connecting ring 232, the first connecting ring 231, and the retaining ring 233 of the first valve core assembly 200, as well as the valve sleeve 100 and the retaining ring 233, the first connecting ring 231, and the second connecting ring 232 of the second valve core assembly 300. The first baffle 900 is sleeved onto the connecting rod 800 and abuts against the second valve core assembly 300 by being tightened with a nut, which is threadedly connected to the connecting rod 800. The first baffle 900 can also be fixed to the connecting rod 800 by other means, such as welding or crimping.

[0065] Specifically, the connecting assembly 700 includes a first connecting sleeve 710, a second connecting sleeve 720, a first mounting ring 730 and a second mounting ring 740. Figure 3As shown. The first connecting sleeve 710 is mounted on the rod body 600 and disposed at the end of the damping core 420 away from the damping seat 410. The first connecting sleeve 710 presses the damping core 420 against the step of the rod body 600, thereby fixing the rod body 600 and the damping core 420. The first mounting ring 730 is mounted on the rod body 600 and abuts the first connecting sleeve 710 to limit the position of the first connecting sleeve 710. In this embodiment, the damping core 420, the first connecting sleeve 710, and the first mounting ring 730 can all be connected to the rod body 600 by riveting, crimping, or other methods. One end of the second connecting sleeve 720 is mounted on the first connecting sleeve 710 and the first mounting ring 730 and abuts the damping core 420. The other end is mounted on the connecting rod 800 and abuts the second connecting ring 232 of the first valve core assembly 200. The second connecting sleeve 720 is connected to the first connecting sleeve 710 and the connecting rod 800, thereby integrally connecting the rod body 600 and the connecting rod 800. The second mounting ring 740 is sleeved on the connecting rod 800 and abuts against the steps of the second connecting sleeve 720 and the connecting rod 800, thereby cooperating with the first baffle 900 to fix the second connecting sleeve 720, the first valve core assembly 200, the valve sleeve 100 and the second valve core assembly 300 on the connecting rod 800.

[0066] In this embodiment, the boost chamber 103 is filled with nitrogen and / or a boost spring is provided. The nitrogen and boost spring are used to apply thrust to the isolation piston 40 so that the isolation piston 40 squeezes the second chamber 102, thereby providing back pressure. When the switch valve 20 moves toward the isolation piston 40, only a small stroke is required to reach the opening pressure of the switch valve 20, thereby quickly connecting the first chamber 101 and the second chamber 102, thereby preventing a vacuum in the first chamber 101. This avoids the problem of the stepless limiter requiring a long stroke to activate, avoids the problem of a vacuum in the first chamber 101, i.e., the rod chamber, and improves the response speed of the stepless limiter. In addition, when the switch valve 20 moves away from the isolation piston 40, the pressure in the boost chamber 103 can push the isolation piston 40 toward the second chamber 102, thereby preventing a vacuum in the second chamber 102.

[0067] In this embodiment, the medium in the first cavity 101 and the second cavity 102 can be gas or liquid.

[0068] The working process of the stepless limiter provided in this embodiment is as follows:

[0069] In the initial state, the medium pressures in the first chamber 101 and the second chamber 102 are balanced. One side of the sealing ring 212 is subject to the medium pressure in the second pressure chamber 203 and the elastic force of the return spring 220, while the other side is subject to the medium pressure in the first chamber 101 or the second chamber 102. The medium pressure acts on the sealing ring 212 through the first axial hole 2311, and the force-bearing area is equal to the cross-sectional area of ​​the first axial hole 2311.

[0070] When an external force is applied to the piston rod 30, causing the on-off valve 20 to move toward the second chamber 102, the medium pressure in the first chamber 101 decreases, while the medium pressure in the second chamber 102 increases, and the compression resistance output by the piston rod 30 continuously increases. Because the isolation piston 40 causes the pressure in the second chamber 102 to rise rapidly, the medium pressure in the second chamber 102 overcomes the elastic force of the return spring 220 of the second valve core assembly 300 within a relatively short stroke, pushing the sleeve unit 210 away from the fixed unit 230, thereby connecting the second chamber 102 and the first pressure chamber 201. As the medium pressure in the second chamber 102 continues to increase, the medium pressure in the first pressure chamber 201 increases to the point where it overcomes the first sealing ring 240 of the first valve core assembly 200, allowing the medium to flow into the first chamber 101. At this point, the compression resistance output by the piston rod 30 is the locking force. At this point, the return spring 220 tends to push the sealing ring 212 to re-press the first connecting ring 231, thereby generating a pressure difference on both sides of the sealing ring 212. The cross section of the pressure difference is the cross section of the first axial hole 2311, and this pressure is balanced by the return spring 220. At the same time, this pressure difference acts on the inner cross section of the cylinder 10 to generate an outward compressive force. When the external force is removed, locking can be achieved at any position.

[0071] When the medium pressure within the second chamber 102 pushes the sleeve unit 210 of the second valve core assembly 300 away from the first connecting ring 231, the medium within the second chamber 102 flows sequentially through the second axial hole 2321, the first axial hole 2311, the first annular gap 202, and the first pressure chamber 201. Due to the decompression effect of the first annular gap 202, a pressure differential is generated across it. As the sleeve body 211 moves away from the first connecting ring 231, the length of the first annular gap 202 gradually decreases, the decompression effect gradually decreases, and the pressure in the first pressure chamber 201 and the connected first chamber 101 gradually increases until the pressure difference between the first chamber 101 and the second chamber 102 stabilizes. At this point, the compression resistance output by the piston rod 30 is the operating force in the compression direction. That is, when the switch valve 20 starts to move, the larger decompression effect of the first annular gap 202 causes a larger pressure difference between the first chamber 101 and the second chamber 102, so that the movement resistance of the switch valve 20 is larger; after the pressure difference stabilizes, the length of the first annular gap 202 is shortened, the decompression effect is reduced, and the movement resistance of the switch valve 20 is correspondingly reduced. When applied to a car door, it can achieve high resistance when leaving the stop position and low resistance to opening and closing the door after leaving the stop position.

[0072] The speed at which the piston rod 30 is pressed by the external force varies, and the flow rate through the first annular gap 202 also varies. As the speed increases, the flow rate increases, and the pressure differential increases. The further the sleeve unit 210 moves away from the first connecting ring 231, the shorter the length of the first annular gap 202 becomes, and the smaller the pressure differential becomes.

[0073] At the same time, the medium can flow from the first axial hole 2311 into the first pressure chamber 201 via the leak hole 2112. When the on-off valve 20 moves at a low speed, the medium flow rate is low, and the pressure-reducing effect of the first annular gap 202 is insignificant. At this time, the pressure difference between the first chamber 101 and the second chamber 102 is small, and there is no need to increase the switching resistance to prevent malfunction. Therefore, the operating resistance is lower than the resistance when the on-off valve 20 moves at a high speed. When the on-off valve 20 moves at a high speed, the flow rate through the first annular gap 202 increases, and the first annular gap 202 has a significant pressure-reducing effect, increasing the pressure difference between the first chamber 101 and the second chamber 102, thereby increasing the resistance to the initial movement of the on-off valve 20. As the length of the first annular gap 202 decreases and the pressure differential decreases, the movement resistance also decreases, thereby achieving a lower opening and closing resistance after leaving the stop position. When the on-off valve 20 moves at a high speed, the medium flow rate is large, and the leak hole 2112's connection between the first axial hole 2311 and the first pressure chamber 201 has little effect on the pressure difference formed in the first annular gap 202.

[0074] As the sliding sleeve unit 210 moves away from the first connecting ring 231, the volume of the second pressure chamber 203 decreases, forcing the medium therein to flow out only through the first damping orifice 2111. The resulting medium resistance hinders the rapid movement of the sliding sleeve unit 210 away from the first connecting ring 231, thereby smoothing the pressure change through the first damping orifice 2111. Simultaneously, as the annular boss exits the first axial hole 2311, its flow cross-section gradually increases, reducing the pressure relief effect and correspondingly decreasing the pressure differential across the first axial hole 2311. These two combined effects ensure that the compression resistance applied to the piston rod 30 decreases steadily from high to low, minimizing impact.

[0075] When the switch valve 20 moves toward the first chamber 101 , the working principle and process are the same.

[0076] When the damping core 420 moves along with the piston rod 30 in the direction away from the second chamber 102, the space of the first damping chamber 401 of the damping core 420 decreases, and the space of the second damping chamber 402 increases. The medium pressure in the first damping chamber 401 increases and flows into the second damping chamber 402 through the second damping hole 403 or the damping groove 404. The generated medium pressure hinders the movement of the damping core 420 to reduce the movement speed and impact, thereby ensuring smooth operation.

[0077] Based on the stepless limiter provided in this embodiment, an automobile is proposed, comprising the stepless limiter.

[0078] 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A stepless limiter, characterized in that: The invention comprises a cylinder (10), an on-off valve (20), a piston rod (30) and an isolating piston (40) inserted in the cylinder (10), wherein the piston rod (30) is connected to the on-off valve (20), a second chamber (102) is formed between the on-off valve (20) and the isolating piston (40), an end of the on-off valve (20) away from the isolating piston (40) is a first chamber (101), and an end of the isolating piston (40) away from the on-off valve (20) is a pressurizing chamber (103); The switch valve (20) comprises a valve sleeve (100), a first valve core assembly (200) and a second valve core assembly (300), wherein the first valve core assembly (200) and the second valve core assembly (300) are respectively inserted into the valve sleeve (100) from both ends of the valve sleeve (100); When the switch valve (20) moves toward the first chamber (101), the medium pressure in the first chamber (101) increases and drives the first valve core assembly (200) to start, thereby connecting the first chamber (101) and the second chamber (102); When the switch valve (20) moves toward the second chamber (102), the medium pressure in the second chamber (102) increases and drives the second valve core assembly (300) to start, thereby connecting the first chamber (101) and the second chamber (102).

2. The stepless limiter according to claim 1, characterized in that: The boosting chamber (103) is filled with nitrogen and / or a boosting spring is provided. The nitrogen and the boosting spring are used to apply a thrust to the isolation piston (40) so that the isolation piston (40) squeezes the second chamber (102).

3. The stepless limiter according to claim 1, characterized in that: The first valve core assembly (200) and the second valve core assembly (300) are symmetrical in structure and are symmetrically arranged on both sides of the valve sleeve (100); the end of the first valve core assembly (200) away from the second valve core assembly (300) is a first cavity (101), and the end of the second valve core assembly (300) away from the first valve core assembly (200) is a second cavity (102); The first valve core assembly (200) comprises a sliding sleeve unit (210), a return spring (220) and a fixing unit (230); one end of the sliding sleeve unit (210) is inserted into the valve sleeve (100), and the other end is sleeved on the fixing unit (230); the return spring (220) is used to apply elastic force to the sliding sleeve unit (210) so that the sliding sleeve unit (210) abuts against the fixing unit (230); When the switch valve (20) moves toward the first chamber (101), the medium pressure in the first chamber (101) increases and overcomes the elastic force of the return spring (220) of the first valve core assembly (200) to push the sliding sleeve unit (210) away from the fixed unit (230), thereby connecting the first chamber (101) and the second chamber (102); When the switch valve (20) moves toward the second chamber (102), the medium pressure in the second chamber (102) increases and overcomes the elastic force of the return spring (220) of the second valve core assembly (300) to push the sliding sleeve unit (210) away from the fixed unit (230), thereby connecting the first chamber (101) and the second chamber (102).

4. The stepless limiter according to claim 3, characterized in that: The fixing unit (230) includes a first connecting ring (231) and a second connecting ring (232); the sleeve unit (210) includes a sleeve body (211); one end of the sleeve body (211) is inserted into the valve sleeve (100), and the other end is sleeved on the first connecting ring (231) and forms a first annular gap (202) with the first connecting ring (231); the switch valve (20) and the cylinder barrel (10) form a first pressure chamber (201); The first connecting ring (231) is provided with a first axial hole (2311), and the second connecting ring (232) is provided with a second axial hole (2321); the first pressure chamber (201), the first annular gap (202), the first axial hole (2311), and the second axial hole (2321) are sequentially connected; and an end of the second axial hole (2321) away from the first axial hole (2311) is connected to the first chamber (101) or the second chamber (102); The sliding sleeve unit (210) abuts against the first connecting ring (231) to block the first axial hole (2311).

5. The stepless limiter according to claim 4, characterized in that: The sliding sleeve unit (210) further comprises a sealing ring (212), which is inserted into the sliding sleeve body (211), with one end of the sealing ring abutting against the sliding sleeve body (211) and the other end abutting against the first connecting ring (231); A truncated cone-shaped protrusion (2121) is provided on the sealing ring (212), and the truncated cone-shaped protrusion (2121) is inserted into the first axial hole (2311) and has a diameter that gradually increases in a direction of exiting the first axial hole (2311).

6. The stepless limiter according to claim 5, characterized in that: The sliding sleeve unit (210) is provided with a first damping hole (2111) and a leakage hole (2112), and the sliding sleeve unit (210) and the valve sleeve (100) enclose a second pressure chamber (203); One end of the first damping hole (2111) is connected to the first pressure chamber (201), and the other end is connected to the second pressure chamber (203); one end of the leakage hole (2112) is connected to the first pressure chamber (201), and the other end is connected to the first axial hole (2311).

7. The stepless limiter according to claim 6, characterized in that: The first valve core assembly (200) further includes a first sealing ring (240), which is sleeved on the fixing unit (230) and inserted into the cylinder (10) for sealing the annular gap between the fixing unit (230) and the cylinder (10); When the medium pressure in the first pressure chamber (201) increases, the medium can flow from the first pressure chamber (201) through the first sealing ring (240) into the first chamber (101) or the second chamber (102).

8. The stepless limiter according to claim 1, characterized in that: It also includes a guide member (50), wherein the guide member (50) is disposed in the first chamber (101) and connected to the switch valve (20); The guide member (50) includes a damping assembly (400), the damping assembly (400) including a damping seat (410) and a damping core (420), the damping core (420) being movable along its own axis and inserted into the damping seat (410), thereby forming a first damping chamber (401) with the damping seat (410) and a second damping chamber (402) with the switch valve (20); The damping seat (410) is provided with a second damping hole (403), and the first damping cavity (401), the second damping hole (403), and the second damping cavity (402) are sequentially connected; A first communicating groove is provided on the outer side of the damping seat (410), and the first communicating groove is used to connect the second damping hole (403) and the second damping chamber (402).

9. The stepless limiter according to claim 1, characterized in that: It also includes a guide member (50), wherein the guide member (50) is disposed in the first chamber (101) and connected to the switch valve (20); The guide member (50) includes a damping assembly (400), the damping assembly (400) including a damping seat (410) and a damping core (420), the damping core (420) being movable along its own axis and inserted into the damping seat (410), thereby forming a first damping chamber (401) with the damping seat (410) and a second damping chamber (402) with the switch valve (20); The inner wall of the damping seat (410) is provided with a damping groove (404), and the first damping cavity (401), the damping groove (404), and the second damping cavity (402) are sequentially connected.

10. An automobile, characterized in that: It comprises the stepless limiter as described in any one of claims 1 to 9.

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