Pressure compensation valve and hydraulic control system

Abstract

The utility model relates to the technical field of hydraulic pressure, in particular to a pressure compensation valve and a hydraulic control system. Due to the fact that the first sealing structure of the valve sleeve is provided with the first sealing part and the second sealing part, and the second sealing structure of the valve element is provided with the third sealing part and the fourth sealing part, when the valve element works, no matter the valve element is located at the first working position or the second working position, the valve element is sealed. Sealing can be achieved through linear contact of the sealing part of the valve sleeve and the sealing part of the valve element, the sealing capacity of the pressure compensation valve is guaranteed, and leakage caused by the fact that oil in the hydraulic control port flows out through the oil port is prevented. According to the hydraulic control system, the sealing effect is guaranteed, meanwhile, the overall structure of the system is more compact, and the manufacturing cost is correspondingly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic pressure, in particular to a pressure compensation valve and a hydraulic control system. Background Art

[0002] The pressure compensating valve provided in the prior art has a valve core that can slide relative to the valve sleeve, resulting in an inevitable gap between the valve core and the valve sleeve. The existence of the gap will correspond to leakage, making the pressure compensating valve in the prior art unsuitable for use in working conditions that require load maintenance.

[0003] Therefore, there is an urgent need for a pressure compensating valve to solve the above technical problems. Utility Model Content

[0004] The purpose of the utility model is to provide a pressure compensating valve and a hydraulic control system, which can avoid leakage of the compensating valve, ensure that the compensating valve can be used normally under specific working conditions, and realize load holding.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] In a first aspect, a pressure compensating valve is provided, comprising:

[0007] A valve sleeve, wherein the valve sleeve has a first sealing structure, an oil port is provided on the valve sleeve, and the first sealing structure has a first sealing portion and a second sealing portion;

[0008] a valve core, the valve core being accommodated in the valve sleeve and being capable of sliding in the valve sleeve, the valve core having a second sealing structure, the second sealing structure having a third sealing portion and a fourth sealing portion;

[0009] In which, one end of the valve sleeve has a hydraulic control port, and the valve core has a first working position and a second working position. When the valve core is in the first working position, the first sealing part is in line contact with the third sealing part to achieve sealing between the valve core and the valve sleeve. When the valve core is in the second working position, the second sealing part is in line contact with the fourth sealing part to achieve sealing between the valve core and the valve sleeve.

[0010] As a preferred technical solution of the above-mentioned pressure compensation valve, one of the first sealing structure and the second sealing structure includes a first annular protrusion and the other includes an annular groove, and at least a portion of the first annular protrusion is located in the annular groove.

[0011] As a preferred technical solution of the above-mentioned pressure compensating valve, the valve sleeve includes a main sleeve and a sub-sleeve, at least part of the sub-sleeve is located in the main sleeve and the two are connected, the side wall forming the annular groove includes part of the side wall of the main sleeve and part of the side wall of the sub-sleeve, and one of the first sealing part and the second sealing part is located in the main sleeve and the other is located in the sub-sleeve.

[0012] As an optimal technical solution for the above-mentioned pressure compensating valve, the main sleeve has an internal connecting groove, at least part of the sub-sleeve is located in the internal connecting groove and is threadedly connected to the main sleeve, and the sub-sleeve is concave on one side close to the valve core to form a limiting groove, and the side wall forming the annular groove includes the side wall of the limiting groove and part of the side wall of the internal connecting groove.

[0013] As a preferred technical solution of the above-mentioned pressure compensation valve, the first sealing portion and the second sealing portion are arranged in parallel or at an angle, and the third sealing portion and the fourth sealing portion are arranged at an angle.

[0014] As a preferred technical solution of the above-mentioned pressure compensation valve, the outer contour of the first annular protrusion is an arc surface.

[0015] As an optimal technical solution for the above-mentioned pressure compensating valve, a throttling structure is provided on the pressure compensating valve, and the oil port includes a first oil port and a second oil port. The throttling structure is used to limit the amount of oil flowing from the first oil port to the second oil port.

[0016] As a preferred technical solution of the above-mentioned pressure compensating valve, the throttling structure includes a throttling hole provided on the valve sleeve.

[0017] As an optimal technical solution of the above-mentioned pressure compensating valve, the pressure compensating valve further includes a sealing ring, the outer peripheral wall of the valve sleeve is provided with a receiving groove, the sealing ring is sleeved on the valve sleeve, and the sealing ring is partially embedded in the valve sleeve.

[0018] As an optimal technical solution for the above-mentioned pressure compensation valve, it includes a valve body and an elastic member, the other end of the valve sleeve extends into the valve body and is connected to the valve body, the elastic member is located in the valve body, and the two ends of the elastic member are respectively against the valve body and the valve core, and the valve core can slide along the axial direction of the valve sleeve under the action of the elastic member to adjust the opening size of the oil port.

[0019] In a second aspect, a hydraulic control system is provided for connecting a hydraulic cylinder, comprising:

[0020] a hydraulic pump and a one-way valve, wherein the outlet of the hydraulic pump is connected to the inlet of the one-way valve, and the outlet of the one-way valve is used to communicate with the hydraulic cylinder;

[0021] a proportional directional valve, wherein the inlet of the proportional directional valve is connected to the outlet of the one-way valve;

[0022] As described in any of the above schemes, the oil port of the pressure compensating valve includes a first oil port and a second oil port, the first oil port and the second oil port are respectively connected to the outlet of the proportional directional valve, and the hydraulic control end of the pressure compensating valve is connected to the second oil port.

[0023] As a preferred technical solution of the above hydraulic control system, the hydraulic control system includes a first throttle valve, which is used to limit the amount of oil flowing from the one-way valve to the pressure compensation valve.

[0024] The utility model has at least the following beneficial effects:

[0025] The pressure compensating valve provided by the utility model has a first sealing structure of the valve sleeve having a first sealing portion and a second sealing portion, and a second sealing structure of the valve core having a third sealing portion and a fourth sealing portion. When the valve core is working, no matter whether the valve core is in the first working position or the second working position, sealing can be achieved through the sealing portion of the valve sleeve and the sealing portion of the valve core, thereby ensuring the sealing ability of the pressure compensating valve and preventing leakage caused by the oil in the hydraulic control port flowing out through the oil port.

[0026] Since the valve sleeve and valve core of the pressure compensating valve cooperate with each other through the first sealing structure and the second sealing structure to achieve the purpose of sealing, it can prevent the oil in the hydraulic control port from flowing out of the pressure compensating valve through the oil port, and prevent the pressure compensating valve from being unstable during operation. Compared with the hydraulic control system in the prior art that adds a reversing valve, the hydraulic control system can ensure the sealing effect while making the overall structure of the system more compact, and the manufacturing cost is also reduced accordingly. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0028] Figure 1 A cross-sectional view of a pressure compensating valve provided in an embodiment of the present utility model;

[0029] Figure 2 for Figure 1 Schematic diagram of a partial state of the medium pressure compensation valve when the valve core is in the first working position;

[0030] Figure 3 for Figure 1Schematic diagram of the partial state of the medium pressure compensation valve when the valve core is in the second working position;

[0031] Figure 4 A schematic diagram of a hydraulic control system provided in the prior art;

[0032] Figure 5 This is a schematic diagram of the hydraulic control system provided in an embodiment of the present utility model.

[0033] In the picture:

[0034] 1. Valve sleeve; 11. Main sleeve; 12. Sub-sleeve; 13. First sealing structure; 131. First sealing part; 132. Second sealing part; 14. First oil port; 15. Second oil port; 16. Orifice; 2. Valve core; 21. Second sealing structure; 211. Third sealing part; 212. Fourth sealing part; 3. Valve body; 4. Elastic member; 5. Hydraulic control port; 6. Sealing ring;

[0035] 100, one-way valve; 200, proportional directional valve; 300, second throttle valve; 400, overflow valve; 500, descent compensation valve; 600, two-position two-way solenoid valve; 700, pressure compensation valve; 800, first throttle valve. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0037] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0038] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0039] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0040] The utility model provides a pressure compensating valve, which can solve the problem of leakage.

[0041] like Figures 1 to 3 As shown, the pressure compensating valve includes a valve sleeve 1 and a valve core 2, wherein the valve sleeve 1 has a first sealing structure 13, and an oil port is provided on the valve sleeve 1. The first sealing structure 13 includes a first sealing portion 131 and a second sealing portion 132. The valve core 2 is accommodated in the valve sleeve 1 and can slide in the valve sleeve 1. The valve core 2 has a second sealing structure 21, and the second sealing structure 21 has a third sealing portion 211 and a fourth sealing portion 212. One end of the valve sleeve 1 has a hydraulic control port 5, and oil passes through the hydraulic control port 5 to push the valve core 2. The valve core 2 has a first working position and a second working position. When the valve core 2 is in the first working position, the first sealing portion 131 and the third sealing portion 211 can be in line contact to achieve sealing between the valve core 2 and the valve sleeve 1. When the valve core 2 is in the second working position, the second sealing portion 132 and the fourth sealing portion 212 can be in line contact to achieve sealing between the valve core 2 and the valve sleeve 1. The provision of the first sealing structure 13 and the second sealing structure 21 can prevent the oil in the hydraulic control port 5 from flowing out of the oil port.

[0042] The pressure compensating valve provided by the present invention has the first sealing structure 13 of the valve sleeve 1 having the first sealing portion 131 and the second sealing portion 132, and the second sealing structure 21 of the valve core 2 having the third sealing portion 211 and the fourth sealing portion 212. When the valve core 2 is working, no matter whether the valve core 2 is in the first working position or the second working position, the sealing portion of the valve sleeve 1 and the sealing portion of the valve core 2 can be in line contact to achieve sealing to ensure the sealing ability of the pressure compensating valve, and prevent leakage caused by the oil in the hydraulic control port 5 flowing out through the oil port. Compared with the sealing by the sealing ring 6 in the prior art, the mutual friction between the sealing parts can be avoided, and the problem of wear and leakage will not occur during use.

[0043] In some embodiments, one of the first sealing structure 13 and the second sealing structure 21 includes a first annular protrusion and the other includes an annular groove, with the first annular protrusion at least partially located within the annular groove. Thus, the two sealing portions of the first annular protrusion cooperate with the two sealing portions of the annular groove to achieve sealing. For example, the second sealing structure 21 includes a first annular protrusion disposed on the outer peripheral wall of the valve core 2, the first annular protrusion having a third sealing portion 211 and a fourth sealing portion 212 disposed in opposite directions. The first sealing structure 13 includes an annular groove disposed on the inner peripheral wall of the valve sleeve 1, the annular groove having a first sealing portion 131 and a second sealing portion 132 disposed in opposite directions. The first annular protrusion is located within the region formed by the annular groove. Thus, when the first annular protrusion is in the first working position, the first sealing portion 131 is in line contact with the third sealing portion 211. When the first annular protrusion is in the second working position, the second sealing portion 132 is in line contact with the fourth sealing portion 212. This achieves the purpose of sealing the valve core 2 during operation and prevents leakage of the pressure compensating valve.

[0044] In some embodiments, the valve sleeve 1 includes a main sleeve 11 and a sub-sleeve 12. The sub-sleeve 12 is at least partially located within the main sleeve 11 and connected to the main sleeve 11. The sidewall forming the annular groove includes a portion of the sidewall of the main sleeve 11 and a portion of the sidewall of the sub-sleeve 12. One of the first sealing portion 131 and the second sealing portion 132 is located in the main sleeve 11, and the other is located in the sub-sleeve 12. The arrangement of the main sleeve 11 and the sub-sleeve 12 ensures that the valve core 2 extends into the valve sleeve 1. This arrangement facilitates installation of the valve core 2 and the valve sleeve 1, preventing partial leakage of the valve core 2 from the valve sleeve 1 due to interference between the first annular protrusion and the valve sleeve 1. For example, the main sleeve 11 and the sub-sleeve 12 are threadedly connected.

[0045] Furthermore, the main sleeve 11 has an internal connecting groove, and at least a portion of the sub-sleeve 12 is located in the internal connecting groove and is threadedly connected to the main sleeve 11. The side of the sub-sleeve 12 near the valve core 2 is recessed to form a limiting groove. The sidewalls forming the annular groove include the sidewalls of the limiting groove and a portion of the sidewalls of the internal connecting groove. The limiting groove and the internal connecting groove cooperate to achieve the connection between the main sleeve 11 and the sub-sleeve 12, making the valve sleeve 1 more compact.

[0046] In some embodiments, the first sealing portion 131 and the second sealing portion 132 are arranged parallel to or at an angle, and the third sealing portion 211 and the fourth sealing portion 212 are arranged at an angle. The angled arrangement between the respective sealing portions can achieve a line seal between the valve core 2 and the valve sleeve 1. Compared to a surface seal achieved by the third sealing portion 211 and the fourth sealing portion 212 being arranged parallel to each other, the line seal can avoid wear between the sealing portions, further ensure the sealing performance between the valve core 2 and the valve sleeve 1, and increase the service life of the pressure compensating valve.

[0047] In this embodiment, the cross-section of the first annular protrusion is trapezoidal, which ensures that the valve core 2 and the valve sleeve 1 are in linear contact with each other to achieve a seal, and the second sealing structure 21 is easier to manufacture. In some embodiments, the outer contour of the first annular protrusion is an arcuate surface, that is, the third sealing portion 211 and the fourth sealing portion 212 are both arcuate surfaces. When the first sealing portion 131 and the second sealing portion 132 are both flat surfaces, the arcuate surface is always in linear contact with the flat surface, and thus a linear seal is always formed between the arcuate surface and the flat surface, thereby preventing leakage of the pressure compensation valve.

[0048] The pressure-compensating valve also includes a valve body 3 and an elastic member 4. The second end of the valve sleeve 1 extends into the valve body 3, and the valve sleeve 1 is connected to the valve body 3. The two ends of the elastic member 4 respectively abut against the valve body 3 and the valve core 2. Under the action of the elastic member 4, the valve core 2 can slide axially along the valve sleeve 1 to adjust the opening size of the oil port. The arrangement of the valve body 3 and the elastic member 4 ensures that when the first end of the valve core 2 is not pushed by the oil, the restoring force of the elastic member 4 pushes the valve core 2 back to its original position. For example, the elastic member 4 is a spring.

[0049] In some embodiments, the pressure compensating valve is provided with a throttling structure. The oil ports include a first oil port 14 and a second oil port 15. The throttling structure is used to limit the amount of oil flowing from the first oil port 14 to the second oil port 15. The throttling structure ensures a stable oil flow when liquid enters the pressure compensating valve, preventing large fluctuations in the oil flow and ensuring stable operation of the internal structure of the pressure compensating valve.

[0050] Specifically, the throttling structure includes a throttling hole 16 provided on the valve sleeve 1. The provision of the throttling hole 16 can further reduce the overall volume of the pressure compensating valve, making the structure of the pressure compensating valve more compact.

[0051] In some embodiments, the pressure-compensating valve further includes a sealing ring 6. A receiving groove is provided on the outer peripheral wall of the valve sleeve 1. The sealing ring 6 is sleeved on the valve sleeve 1 and partially located within the receiving groove. That is, the sealing ring 6 is partially embedded in the valve sleeve 1. The provision of the sealing ring 6 ensures a sealing effect between the pressure-compensating valve and other structures when the pressure-compensating valve is installed in other structures (such as a valve block).

[0052] In the prior art, such as Figure 4 As shown, oil from the hydraulic pump enters port P, passes through check valve 100, and enters the rodless chamber of the cylinder through port A. The cylinder rises, and relief valve 400 limits the maximum pressure of the cylinder's ascent to protect it. When oil supply stops, the check valve 100, proportional directional valve 200, and two-position, two-way solenoid valve 600 are all sealed, maintaining pressure in the cylinder. When the cylinder needs to descend, the proportional directional valve 200 and two-position, two-way solenoid valve 600 are energized, and the descent compensation valve 500 ensures a constant descent speed, unaffected by load fluctuations. During the pressure-maintaining process, leakage occurs from port a to port b of the descent compensation valve 500, because the spool valve structure connects port a to port b. This requires the use of a two-position, two-way solenoid valve 600 to maintain pressure. However, the presence of this valve increases costs and the volume occupied by the hydraulic system.

[0053] To this end, the present invention also provides a hydraulic control system in an embodiment for controlling the oil in and out of the hydraulic cylinder connected to the hydraulic control system. Figure 5 As shown, the hydraulic control system includes a hydraulic pump, a one-way valve 100, a proportional directional valve 200 and a pressure compensating valve 700, wherein the pressure compensating valve 700 is the pressure compensating valve provided in an embodiment of the present invention, the outlet of the hydraulic pump is connected to the inlet of the one-way valve 100, and the outlet of the one-way valve 100 is used to connect to the hydraulic cylinder; the inlet of the proportional directional valve 200 is connected to the outlet of the one-way valve 100; the first oil port 14 and the second oil port 15 of the pressure compensating valve are respectively connected to the outlet of the proportional directional valve 200, and the hydraulic control end of the pressure compensating valve is connected to the second oil port 15.

[0054] Since the valve sleeve 1 and the valve core 2 of the pressure compensating valve cooperate with each other through the first sealing structure 13 and the second sealing structure 21 to achieve the purpose of sealing, it can prevent the oil in the hydraulic control port 5 from flowing out of the pressure compensating valve through the oil port, and prevent the pressure compensating valve from being unstable during operation. Compared with the hydraulic control system in the prior art that adds a reversing valve, the hydraulic control system can ensure the sealing effect while making the overall structure of the system more compact, and the manufacturing cost is also reduced accordingly.

[0055] In some embodiments, the hydraulic system further includes a second throttle valve 300 and a relief valve 400. The inlet of the second throttle valve 300 is connected to the outlet of the one-way valve 100, and the outlet of the second throttle valve 300 is connected to the inlet of the relief valve 400. The outlet of the relief valve 400 is connected to the oil tank. The configuration of the relief valve 400 prevents excessive pressure entering port A of the oil cylinder, which may cause damage to the oil cylinder. The configuration of the second throttle valve 300 ensures a stable amount of oil flowing into the relief valve 400, avoiding internal fluctuations. The hydraulic control system includes a first throttle valve 800, which is used to limit the amount of oil flowing from the one-way valve 100 to the pressure compensation valve 700, thereby avoiding internal fluctuations in the valve.

[0056] Furthermore, the above are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions are possible for those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A pressure compensating valve, characterized in that: include: A valve sleeve (1), the valve sleeve (1) having a first sealing structure (13), an oil port being provided on the valve sleeve (1), the first sealing structure (13) having a first sealing portion (131) and a second sealing portion (132); A valve core (2), the valve core (2) being accommodated in the valve sleeve (1) and capable of sliding in the valve sleeve (1), the valve core (2) having a second sealing structure (21), the second sealing structure (21) having a third sealing portion (211) and a fourth sealing portion (212); Wherein, one end of the valve sleeve (1) has a hydraulic control port (5), and the valve core (2) has a first working position and a second working position. When the valve core (2) is in the first working position, the first sealing portion (131) is in line contact with the third sealing portion (211) to achieve sealing between the valve core (2) and the valve sleeve (1); when the valve core (2) is in the second working position, the second sealing portion (132) is in line contact with the fourth sealing portion (212) to achieve sealing between the valve core (2) and the valve sleeve (1).

2. The pressure compensating valve according to claim 1, characterized in that One of the first sealing structure (13) and the second sealing structure (21) includes a first annular protrusion and the other includes an annular groove, and at least a portion of the first annular protrusion is located in the annular groove.

3. The pressure compensating valve according to claim 2, characterized in that The valve sleeve (1) includes a main sleeve (11) and a sub-sleeve (12), at least a portion of the sub-sleeve (12) is located in the main sleeve (11) and the two are connected, the side wall forming the annular groove includes a portion of the side wall of the main sleeve (11) and a portion of the side wall of the sub-sleeve (12), and one of the first sealing portion (131) and the second sealing portion (132) is located in the main sleeve (11) and the other is located in the sub-sleeve (12).

4. The pressure compensating valve according to claim 3, characterized in that The main sleeve (11) has an inner connecting groove, at least a portion of the sub-sleeve (12) is located in the inner connecting groove and is threadedly connected to the main sleeve (11), and the sub-sleeve (12) is concave on one side close to the valve core (2) to form a limiting groove, and the side wall forming the annular groove includes the side wall of the limiting groove and a portion of the side wall of the inner connecting groove.

5. The pressure compensating valve according to claim 2, characterized in that: The first sealing portion (131) and the second sealing portion (132) are arranged in parallel or at an angle, and the third sealing portion (211) and the fourth sealing portion (212) are arranged at an angle.

6. The pressure compensating valve according to claim 2, characterized in that The outer contour of the first annular protrusion is an arc surface.

7. The pressure compensating valve according to any one of claims 1 to 6, characterized in that: The invention comprises a valve body (3) and an elastic member (4), wherein the other end of the valve sleeve (1) extends into the valve body (3) and is connected to the valve body (3), and the elastic member (4) is located in the valve body (3). The two ends of the elastic member (4) respectively abut against the valve body (3) and the valve core (2), and the valve core (2) can slide along the axial direction of the valve sleeve (1) under the action of the elastic member (4) to adjust the opening size of the oil port.

8. A hydraulic control system for connecting a hydraulic cylinder, characterized in that: include: A hydraulic pump and a one-way valve (100), wherein the outlet of the hydraulic pump is connected to the inlet of the one-way valve (100), and the outlet of the one-way valve (100) is used to communicate with the hydraulic cylinder; a proportional directional valve (200), wherein the inlet of the proportional directional valve (200) is connected to the outlet of the one-way valve (100); The pressure compensating valve (700) according to any one of claims 1 to 7, wherein the oil port of the pressure compensating valve (700) comprises a first oil port (14) and a second oil port (15), the first oil port (14) and the second oil port (15) being respectively connected to the outlet of the proportional directional valve (200), and the hydraulic control end of the pressure compensating valve (700) is connected to the second oil port (15).

9. The hydraulic control system according to claim 8, characterized in that: The hydraulic control system includes a first throttle valve (800), which is used to limit the amount of oil flowing from the one-way valve (100) to the pressure compensation valve (700).

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