A hydraulic valve

Abstract

The present invention discloses a hydraulic valve, comprising an upper valve body, a lower valve body, a pressure compensation plate, and a valve core. The upper surface of the lower valve body is provided with a lower oil inlet groove, a lower oil outlet groove, and a lower low-pressure groove, respectively. The valve core is provided with a middle oil inlet groove, a middle oil outlet groove, and middle and low-pressure holes, respectively. The pressure compensation plate is provided with an upper oil inlet groove, an upper oil outlet groove, and an upper low-pressure groove, respectively. An oil inlet port, an oil outlet port, and an oil return port are provided on the lower surface of the lower valve body. An oil inlet flow channel, an oil outlet flow channel, and a low-pressure flow channel are respectively provided in the lower valve body. The pressure compensation plate is provided with an upper low-pressure hole. The upper valve body is further provided with a first pressure adjustment hole for inputting high-pressure control oil to a first regulating piston in a first regulating chamber, and a second pressure adjustment hole for inputting working pressure control oil to a second regulating piston in a second regulating chamber. The present invention solves the technical problems of the valve core being easily worn by contaminants and prone to eccentric jamming during movement.

Description

Technical Field

[0001] The present application relates to the field of fluid transmission and control, and in particular to a hydraulic valve. Background Art

[0002] Hydraulic valves are important and critical control components in hydraulic systems, controlling the flow rate, pressure, and flow direction of the hydraulic system to meet the functional requirements of the hydraulic system's actuators. The accuracy, reliability, and stability of hydraulic valves directly determine the performance of the entire hydraulic system. Therefore, to ensure system performance, it is necessary to improve the reliability of hydraulic valves and reduce their failure rate.

[0003] The key components of existing hydraulic valves are the cylindrical stepped valve core and valve body (or valve sleeve). Wear and eccentric clamping of the valve core and valve body are the main causes of failure of existing hydraulic valves. To ensure that the valve core and valve body can slide normally, the working gap between the two must be much larger than the diameter of the oil contaminant particles, which can easily allow impurities in the oil to enter the working gap, scratching the valve core surface during operation, causing wear and even jamming. Due to the existence of the jet angle at the valve core oil inlet, although the valve core cylindrical surface is provided with a pressure-equalizing groove and the valve body oil inlet annular cavity adopts a concentric structure, the valve core will still become eccentric during the movement under the action of hydraulic impact force, resulting in an unbalanced radial force on the valve core, increasing the friction resistance of movement, and easily causing the valve core to jam.

[0004] Therefore, the hydraulic valve in the above-mentioned prior art has at least the following technical problems: the valve core is easily worn by contaminants and is easily eccentrically stuck during movement.

[0005] Application Contents

[0006] The embodiment of the present application provides a hydraulic valve to solve the technical problem in the prior art that the valve core of the hydraulic valve is easily worn by contaminants and is prone to eccentric jamming during movement. The embodiment of the present application sets a pressure compensation plate on the valve core and sets a pressure compensation device on the pressure compensation plate. By adjusting the pressure compensation device, the pressure compensation plate moves downward and presses the valve core, so that an infinitesimal gap can be achieved between the upper and lower end surfaces of the valve core, thereby preventing oil contaminants and particulate matter from entering the working gap. At the same time, the compressed valve core is also less likely to be eccentric, making the valve core less likely to be scratched, worn, or jammed by contaminants and less likely to be eccentric and jammed during movement, thereby achieving the technical effect of a durable and easy-to-use hydraulic valve.

[0007] To solve the above-mentioned problem, an embodiment of the present application provides a hydraulic valve, comprising an upper valve body and a lower valve body fixedly connected in an upper and lower manner. The lower surface of the upper valve body is provided with a groove, and a pressure compensation plate that can only move up and down is disposed in the groove. The upper surface of the lower valve body is provided with an upwardly protruding boss, and a valve core is disposed between the boss and the pressure compensation plate. One side of the valve core is connected to a driving device that drives the valve core to move left and right, and the other side of the valve core is connected to a reset device.

[0008] A lower oil inlet groove, a lower oil outlet groove and a lower low-pressure groove are respectively provided on the upper surface of the boss; a middle oil inlet groove, a middle oil outlet groove and middle and low-pressure holes are respectively provided on the valve core, and an upper oil inlet groove, an upper oil outlet groove and an upper low-pressure groove are respectively provided on the pressure compensation plate; the lower oil inlet groove and the upper oil inlet groove are symmetrically arranged up and down, the lower oil outlet groove and the upper oil outlet groove are symmetrically arranged up and down, and the lower low-pressure groove and the upper low-pressure groove are symmetrically arranged up and down; the middle oil outlet groove and the middle oil inlet groove are spaced apart from each other on the left and right, and the length of the middle oil outlet groove in the left and right direction is greater than the distance between the lower oil outlet groove and the lower oil inlet groove;

[0009] An oil inlet, an oil outlet and an oil return port are provided on the lower surface of the lower valve body, and an oil inlet flow channel, an oil outlet flow channel and a low-pressure flow channel are respectively provided in the lower valve body. The lower oil inlet groove is connected to the oil inlet through the oil inlet flow channel, the lower oil outlet groove is connected to the oil outlet through the oil outlet flow channel, and the lower low-pressure groove is connected to the oil return port through the low-pressure flow channel.

[0010] The lower oil inlet groove, the middle oil inlet groove and the upper oil inlet groove are aligned vertically to form a high-pressure chamber; the lower oil outlet groove, the middle oil outlet groove and the upper oil outlet groove are aligned vertically to form a working chamber; the lower low-pressure groove, the middle and low-pressure holes and the upper low-pressure groove are aligned vertically to form a low-pressure chamber; the high-pressure chamber is connected to the oil inlet port via the oil inlet flow channel to form an oil inlet channel; the working chamber is connected to the oil outlet port via the oil outlet flow channel to form an oil outlet channel; the low-pressure chamber is connected to the oil return port via the low-pressure flow channel to form an oil return channel;

[0011] The pressure compensation plate is provided with a plurality of upper low-pressure holes, the bottom openings of the upper low-pressure holes extend into the upper low-pressure groove and communicate with the upper low-pressure groove, and the top openings of the upper low-pressure holes are located on the upper surface of the pressure compensation plate;

[0012] The hydraulic valve further includes a pressure compensating device, the pressure compensating device including a first mounting groove and a second mounting groove provided on the lower surface of the upper valve body, wherein the first mounting groove and the upper surface of the pressure compensating plate enclose a first regulating chamber, and the second mounting groove and the upper surface of the pressure compensating plate enclose a second regulating chamber; a first regulating piston that can only move up and down is provided in the first regulating chamber, and a second regulating piston that can only move up and down is provided in the second regulating chamber, and a first sealing device is provided between the inner wall surface of the first regulating chamber and the outer peripheral surface of the first regulating piston, and a second sealing device is provided between the inner wall surface of the second regulating chamber and the outer peripheral surface of the second regulating piston;

[0013] The upper valve body is also provided with a first pressure regulating hole for inputting high-pressure control oil to the first regulating chamber above the first regulating piston and a second pressure regulating hole for inputting working pressure control oil to the second regulating chamber above the second regulating piston; the bottom end of the first pressure regulating hole is connected to the bottom of the first mounting groove, the top end of the first pressure regulating hole is located on the upper surface of the valve body and is connected to the oil outlet, the bottom end of the second pressure regulating hole is connected to the bottom of the second mounting groove, the top end of the second pressure regulating hole is located on the upper surface of the valve body and is connected to the oil inlet.

[0014] Furthermore, the projection of the lower oil outlet groove on the lower end surface of the valve core is a first rectangle, the projection of the lower oil inlet groove on the upper end surface of the valve core is a second rectangle, the wide side of the first rectangle and the long side of the second rectangle are parallel and aligned, and the long side of the first rectangle and the wide side of the second rectangle are collinear.

[0015] Furthermore, the lower oil inlet groove and the lower oil outlet groove are both rectangular grooves, and the lower oil inlet groove and the lower oil outlet groove are arranged at intervals on the left and right, and the lower low-pressure groove is a rectangular annular groove surrounding the lower oil inlet groove and the lower oil outlet groove.

[0016] Furthermore, the upper oil inlet groove and the upper oil outlet groove are both rectangular grooves, and the upper oil inlet groove and the upper oil outlet groove are arranged at intervals, and the upper low-pressure groove is a rectangular annular groove surrounding the upper oil inlet groove and the upper oil outlet groove.

[0017] Furthermore, the valve core is provided with a plurality of rectangular medium and low pressure holes arranged at intervals.

[0018] Furthermore, the upper low-pressure holes correspond one to one with the middle and low-pressure holes.

[0019] Furthermore, the reset device includes a spring and a spring pressure rod extending horizontally from left to right, the left end of the spring pressure rod penetrates between the pressure compensation plate and the valve core, the left end of the spring pressure rod is connected to a spring pressure head through a spring, the spring can be extended and retracted in the left and right directions, and the spring pressure head is aligned with the right side of the valve core; a baffle is fixed to the right side of the upper valve body and the lower valve body, the right end of the spring pressure rod penetrates the baffle, and the spring pressure rod is threadedly connected to the baffle.

[0020] Alternatively, the right side of the middle oil outlet groove is the valve port of the valve core, and the projection of the valve port on the upper surface of the valve core is an oblique line, a broken line or a curve.

[0021] Furthermore, the valve core is circular, and the boss is cylindrical.

[0022] Furthermore, the driving device is a switching electromagnet, a proportional electromagnet or a pilot valve.

[0023] The above one or more technical solutions in the embodiments of the present application have at least one or more of the following technical effects:

[0024] A hydraulic valve described in an embodiment of the present application is configured to provide a pressure compensation plate on a floating valve core, and a pressure compensation device on the pressure compensation plate. The pressure compensation device is adjusted to cause the pressure compensation plate to move downward and press the valve core, so that an infinitely small gap can be achieved between the upper and lower end surfaces of the valve core, thereby preventing oil contaminants and particulate matter from entering the working gap. This effectively solves the technical problem in the prior art that impurities are easily introduced into the working gap of the hydraulic valve because the working gap of the hydraulic valve is much larger than the diameter of the oil contaminant particles, and achieves the technical effect that the valve core is not contaminated or scratched and will not get stuck.

[0025] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a cross-sectional view of a hydraulic valve in an embodiment of the present invention;

[0027] Figure 2 This is a structural schematic diagram of a hydraulic valve in an embodiment of the present invention;

[0028] Figure 3 for Figure 2 Middle BB section view;

[0029] Figure 4An exploded view of a portion of the structure of a hydraulic valve according to an embodiment of the present invention;

[0030] Figure 5 A schematic diagram of pressure calculation of a hydraulic valve in an embodiment of the present invention Figure 1 ;

[0031] Figure 6 A schematic diagram of pressure calculation of a hydraulic valve in an embodiment of the present invention Figure 2 .

[0032] Explanation of the accompanying drawings: drive device 1, upper valve body 2, pressure compensation plate 3, first regulating piston 4, second regulating piston 5, valve core 6, lower valve body 7, spring pressure head 8, spring 9, baffle 10, spring pressure rod 11, lower oil inlet groove m1, middle oil inlet groove m2, upper oil inlet groove m3, lower oil outlet groove n1, middle oil outlet groove n2, upper oil outlet groove n3, lower low-pressure groove t1, middle and low-pressure hole t2, upper low-pressure groove t3, upper low-pressure hole t4, oil inlet M, oil outlet N, oil return port T, oil inlet channel m, oil outlet channel n, low-pressure channel t, high-pressure chamber M0, working chamber N0, low-pressure chamber T0, first pressure regulating hole V, second pressure regulating hole U. DETAILED DESCRIPTION

[0033] The embodiments of the present application provide a hydraulic valve to solve the technical problems in the prior art that the valve core of the hydraulic valve is easily worn by contaminants and is prone to eccentric jamming during movement.

[0034] In the existing technology, since the working gap between the cylindrical stepped valve core and the valve body of the hydraulic valve is much larger than the diameter of the oil contaminant particles, impurities can easily enter the working gap of the hydraulic valve, causing wear and even jamming; the cylindrical stepped valve core and valve body structure itself can easily become eccentric during the movement under the action of hydraulic impact force, causing the valve core to jam.

[0035] In order to solve the above technical problems, the overall idea of ​​the technical solution provided by this application is as follows: by arranging a pressure compensation plate on the floating valve core, and arranging a pressure compensation device on the pressure compensation plate, adjusting the pressure compensation device to make the pressure compensation plate move downward and press the valve core, so that the upper and lower end surfaces of the valve core can achieve an infinitely small gap, thereby preventing oil contaminants and particulate matter from entering the working gap. At the same time, the compressed valve core is also not prone to eccentricity; it effectively solves the technical problem in the prior art that the valve core of the hydraulic valve is easily worn by contaminants and is prone to eccentric jamming during movement, so that the valve core is not easily scratched, worn, or jammed by contaminants and is not prone to eccentric jamming during movement, thereby achieving the technical effect of the hydraulic valve being durable and easy to use.

[0036] The technical solution of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. Unless there is a conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0037] Figure 1 is a cross-sectional view of a hydraulic valve according to an embodiment of the present invention. Figure 2 FIG. 1 is a structural diagram of a hydraulic valve according to an embodiment of the present invention. Figure 1 、 2 As shown, the hydraulic valve includes an upper valve body 2 and a lower valve body 7 fixedly connected to each other, a groove is provided on the lower surface of the upper valve body 2, and a pressure compensation plate 3 that can only move up and down is provided in the groove; an upwardly protruding boss is provided on the upper surface of the lower valve body 7, a valve core 6 is provided between the boss and the pressure compensation plate 3, and one side of the valve core 6 is connected to a driving device 1 that drives the valve core 6 to move left and right, and the other side of the valve core 6 is connected to a reset device.

[0038] It should be noted that this embodiment is based on Figure 1 The upper direction is the direction above Figure 1 The bottom of is the downward direction, Figure 1 The left end is the left direction, Figure 1 The right end of is the right direction, and the limitations of the left, right, up and down directions are only for the convenience of description and are not limitations on the technical solution of the present invention.

[0039] Specifically, the drive device 1 is fixed to the left side of the upper valve body 2. The groove leaves only vertical clearance for the pressure compensation plate 3 to move up and down, limiting its movement to that of the upper and lower parts. The pressure compensation plate 3, the valve core 6, and the lower valve body 7 are all made of a material with high hardness, wear resistance, low friction coefficient, and a high surface finish, such as ceramic.

[0040] like Figure 4As shown, a lower oil inlet groove m1, a lower oil outlet groove n1 and a lower low-pressure groove t1 are respectively provided on the upper surface of the boss, a middle oil inlet groove m2, a middle oil outlet groove n2 and a middle and low-pressure hole t2 are respectively provided on the valve core 6, and an upper oil inlet groove m3, an upper oil outlet groove n3 and an upper low-pressure groove t3 are respectively provided on the pressure compensation plate 3; the lower oil inlet groove m1 and the upper oil inlet groove m3 are symmetrically arranged up and down, the lower oil outlet groove n1 and the upper oil outlet groove n3 are symmetrically arranged up and down, and the lower low-pressure groove t1 and the upper low-pressure groove t3 are symmetrically arranged up and down; the middle oil outlet groove n2 and the middle oil inlet groove m2 are spaced apart from each other on the left and right, and the length of the middle oil outlet groove n2 in the left and right direction is greater than the distance between the lower oil inlet groove m1 and the lower oil outlet groove n1, so that the middle oil outlet groove n2 can simultaneously connect the oil inlet channel and the oil outlet channel when the valve core 6 is in the open state.

[0041] Specifically, the lower oil inlet groove m1 and the upper oil inlet groove m3 are symmetrically arranged about the plane where the valve core 6 is located, the lower oil outlet groove n1 and the upper oil outlet groove n3 are symmetrically arranged about the plane where the valve core 6 is located, and the lower low-pressure groove t1 and the upper low-pressure groove t3 are symmetrically arranged about the plane where the valve core 6 is located.

[0042] like Figure 1 、 3 As shown, an oil inlet M, an oil outlet N and an oil return port T are provided on the lower surface of the lower valve body 7, and an oil inlet channel m, an oil outlet channel n and a low-pressure channel t are respectively provided in the lower valve body 7. The lower oil inlet groove m1 is connected to the oil inlet M through the oil inlet channel m, the lower oil outlet groove n1 is connected to the oil outlet N through the oil outlet channel n, and the lower low-pressure groove t1 is connected to the oil return port T through the low-pressure channel t.

[0043] The lower oil inlet groove m1, the middle oil inlet groove m2 and the upper oil inlet groove m3 are aligned and connected in vertical direction to form a high-pressure chamber M0; the lower oil outlet groove n1, the middle oil outlet groove n2 and the upper oil outlet groove n3 are aligned and connected in vertical direction to form a working chamber N0; the lower low-pressure groove t1, the middle and low-pressure holes t2 and the upper low-pressure groove t3 are aligned and connected in vertical direction to form a low-pressure chamber T0; the high-pressure chamber M0 is connected with the oil inlet port M through the oil inlet channel m to form an oil inlet channel; the working chamber N0 is connected with the oil outlet port N through the oil outlet channel n to form an oil outlet channel; the low-pressure chamber T0 is connected with the oil return port T through the low-pressure channel t to form an oil return channel.

[0044] Specifically, when the valve core 6 is in its original position, the oil inlet and outlet passages are independent of each other, and the valve core 6 is in a closed state. When the valve core 6 moves rightward under the drive of the drive device 1, the left side of the middle oil outlet groove n2 communicates with the lower oil outlet groove n1 and the upper oil outlet groove n3, respectively. The right side of the middle oil outlet groove n2 penetrates the left side of the lower oil inlet groove m1 to form a first working gap. The right side of the middle oil outlet groove n2 penetrates the left side of the upper oil inlet groove m3 to form a second working gap. The oil inlet and outlet passages communicate through the first and second working gaps, and the valve core 6 opens.

[0045] The pressure compensation plate 3 is provided with a plurality of upper low-pressure holes t4, the bottom openings of the upper low-pressure holes t4 extend into the upper low-pressure groove t3 and are connected to the upper low-pressure groove t3, and the top openings of the upper low-pressure holes t4 are located on the upper surface of the pressure compensation plate 3.

[0046] The hydraulic valve also includes a pressure compensation device, which includes a first mounting groove and a second mounting groove opened on the lower surface of the upper valve body 2, and the first mounting groove and the upper surface of the pressure compensation plate 3 enclose a first regulating chamber, and the second mounting groove and the upper surface of the pressure compensation plate 3 enclose a second regulating chamber; a first regulating piston 4 that can only move up and down is provided in the first regulating chamber, and a second regulating piston 5 that can only move up and down is provided in the second regulating chamber, and a first sealing device is provided between the inner wall surface of the first regulating chamber and the outer peripheral surface of the first regulating piston 4, and a second sealing device is provided between the inner wall surface of the second regulating chamber and the outer peripheral surface of the second regulating piston 5.

[0047] The upper valve body 2 is also provided with a first pressure regulating hole U for inputting high-pressure control oil to the top of the first regulating piston 4 and a second pressure regulating hole V for inputting working pressure control oil to the top of the second regulating piston 5; the bottom end of the first pressure regulating hole U is connected to the bottom of the first mounting groove, the top end of the first pressure regulating hole U is located on the upper surface of the valve body 2 and is connected to the oil outlet N, the bottom end of the second pressure regulating hole V is connected to the bottom of the second mounting groove, the top end of the second pressure regulating hole V is located on the upper surface of the valve body 2 and is connected to the oil inlet M.

[0048] Furthermore, the projection of the lower oil outlet groove n1 on the lower end surface of the valve core 6 is a first rectangle, and the projection of the lower oil inlet groove m1 on the upper end surface of the valve core 6 is a second rectangle. The wide side of the first rectangle and the long side of the second rectangle are parallel and aligned, and the long side of the first rectangle and the wide side of the second rectangle are collinear.

[0049] Furthermore, the lower oil inlet groove m1 and the lower oil outlet groove n1 are both rectangular grooves, and the lower oil inlet groove m1 and the lower oil outlet groove n1 are spaced apart from each other, and the lower low-pressure groove t1 is a rectangular annular groove surrounding the lower oil inlet groove m1 and the lower oil outlet groove n1.

[0050] Furthermore, the upper oil inlet groove m3 and the upper oil outlet groove n3 are both annular grooves, and the upper oil inlet groove m3 and the upper oil outlet groove n3 are spaced apart, and the upper low-pressure groove t3 is a rectangular annular groove surrounding the upper oil inlet groove m3 and the upper oil outlet groove n3.

[0051] Furthermore, the valve core 6 is provided with a plurality of rectangular medium and low pressure holes t2 arranged at intervals, and the medium and low pressure holes t2 are vertically aligned with and connected to the lower low pressure groove t1 and the upper low pressure groove t3.

[0052] Furthermore, the upper low-pressure hole t4 corresponds to the middle and low-pressure holes t2 on a one-to-one basis.

[0053] Furthermore, the reset device includes a spring 9 and a spring pressure rod 11 extending horizontally from left to right, the left end of the spring pressure rod 11 penetrates between the pressure compensation plate 3 and the valve core 6, and the left end of the spring pressure rod 11 is connected to the spring pressure head 8 through the spring 9, the spring 9 can be extended and retracted in the left and right directions, and the spring pressure head 8 is aligned with the right side of the valve core 6; a baffle 10 is fixed to the right side of the upper valve body 2 and the lower valve body 2, the right end of the spring pressure rod 11 penetrates the baffle 10, and the spring pressure rod 11 is threadedly connected to the baffle 10.

[0054] Specifically, the preload force accumulated by the spring 9 can reset the valve core 6 .

[0055] Furthermore, the first sealing device and the second sealing device are both sealing rings.

[0056] Specifically, the sealing rings on the first regulating piston 4 and the second regulating piston 5 are used to isolate the oil on the upper and lower end surfaces of the first regulating piston 4 or the second regulating piston 5 .

[0057] Furthermore, the valve core 6 may be circular, elliptical or rectangular, and the boss may be cylindrical.

[0058] Furthermore, the driving device is a switching electromagnet, a proportional electromagnet or a pilot valve.

[0059] Specifically, when the drive device 1 is a switching electromagnet, the hydraulic valve described in this embodiment is a switching valve; when the drive device 1 is a proportional electromagnet, the hydraulic valve described in this embodiment is a proportional valve; when the drive device 1 is a pilot-stage valve, the hydraulic valve described in this embodiment is a servo valve. Furthermore, the hydraulic valve described in this embodiment can also serve as the pilot stage of other main valves, such as a servo valve.

[0060] The pressure compensation plate 3, the valve core 6 and the lower valve body 7 are positioned by pin shafts, working planes and other means to ensure that the pressure compensation plate 3 can only float in the vertical direction and cannot rotate; the valve core 6 can only slide left and right and cannot rotate, thereby ensuring that the valve port of the valve core 6 (on the right side of the middle oil outlet groove n2) coincides with the opening edges of the upper valve body 2 and the lower valve body 7 (lower oil inlet groove m1 and upper oil inlet groove m3).

[0061] The working principle of the hydraulic valve described in this embodiment is as follows:

[0062] The high-pressure oil in the high-pressure chamber M0 flows into the low-pressure chamber N0 through the gap between the valve core 6 and the lower valve body 7, and the gap between the valve core 6 and the pressure compensation plate 3 to form a pressure oil film; similarly, the oil in the working chamber N0 flows into the low-pressure chamber T0 through the gap between the valve core 6 and the lower valve body 7, and the gap between the valve core 6 and the pressure compensation plate 3 to form a pressure oil film. The pressure oil film makes the gap pressures on the upper and lower end surfaces of the valve core 8 equal, thereby causing the valve core 8 to be suspended.

[0063] A pressure oil film forms between the lower end surface of the pressure compensation plate 3 and the upper end surface of the valve core 6. On the upper end surface of the pressure compensation plate 3, the oil in the low-pressure chamber T0 passes through the upper low-pressure hole t4 on the pressure compensation plate 3, covering the upper end surface of the pressure compensation plate 3 and forming a low-pressure oil film. On the other hand, the high-pressure control oil introduced through the second pressure adjustment hole U acts on the second adjustment piston 5, and the working pressure control oil introduced through the first pressure adjustment hole V acts on the first adjustment piston 4. Both the first and second adjustment pistons 4 and 5 act on the upper end surface of the pressure compensation plate 3, achieving pressure compensation.

[0064] When the driving device 1 is not in operation, the valve core 6 is in its original position, the valve core 6 is closed, the high-pressure chamber M0 is disconnected from the working chamber N0, that is, the oil inlet M is disconnected from the oil outlet N. The valve core 6 is in a suspended state due to the action of the oil film with equal pressure on its upper and lower end surfaces.

[0065] The lower end surface of the pressure compensation plate 6 is subjected to the vertical upward force of the pressure oil film, and the upper end surface of the pressure compensation plate 6 is subjected to the resultant force F of the vertical downward pressure of the first regulating piston 4 and the second regulating piston 5 and the pressure of the return oil port T on the lower end surface. The direction of the resultant force F is vertically downward. Here, the expression of the resultant force F of the upper and lower end surfaces of the pressure compensation plate 6 is ensured as follows:

[0066] F=P·S4+A·S3-P2·S2-A2·S1>0

[0067] In the above formula, P is the oil inlet pressure, A is the oil outlet pressure, P2 is the equivalent pressure of the pressure oil film distribution of the end surface clearance between the high-pressure chamber M0 and the low-pressure chamber T0 valve core 6, A2 is the equivalent pressure of the pressure oil film distribution of the end surface clearance between the working chamber N0 and the low-pressure chamber T0 valve core 6; S4 is the end surface area of ​​the second regulating piston 5, S3 is the end surface area of ​​the first regulating piston 4, S2 is the equivalent area of ​​the pressure oil film of the end surface clearance between the high-pressure chamber M0 and the low-pressure chamber T0 valve core 6, and S1 is the equivalent area of ​​the pressure oil film of the end surface clearance between the working chamber N0 and the low-pressure chamber T0 valve core 6, as shown in FIG. Figure 5 、 6 shown.

[0068] When F>0, the pressure on the upper end surface of the pressure compensation plate 3 is greater than the pressure on the lower end surface, and the pressure compensation plate 3 moves vertically downward to press the valve core 6, and its pressing force is F.

[0069] Assuming that the pressures at the oil inlet M and the oil outlet N remain unchanged, the required resultant force F, i.e., the clamping force of the pressure compensation plate 3 on the valve core 6, can be obtained by controlling the pressure variables P2, A2 and the area variables S4, S3, S2, and S1. This allows the clearances between the valve core 6 and the lower valve body 7 and the upper and lower end surfaces of the pressure compensation plate 3 to be adjusted to be smaller than the order of magnitude of the diameter of pollutant particles, thereby preventing the entry of oil pollutants and particulate matter. At the same time, the plate-shaped valve core 6 is not prone to eccentric jamming due to being compressed during operation.

[0070] When the drive device 1 is activated, it pushes the valve core 6 to the right, the valve port is opened (i.e., the first working gap and the second working gap appear), and the high-pressure chamber M0 is connected to the working chamber N0, that is, the oil inlet M is connected to the oil outlet N. The movement of the valve core 6 has no effect on the oil film pressure distribution on the upper and lower end surfaces of the valve core 6. The valve core 6 is compressed under the action of the resultant force F under the set conditions. At this time, the end surface gap between the valve core 6 and the lower valve body 7 and the pressure compensation plate 3 is very small. When the oil passes through the valve port, pollutants or particulate matter cannot enter the end surface gap, which will not cause the valve core 6 to be scratched, worn or even stuck by pollutants, thereby improving the anti-pollution ability. The valve core 6, the lower valve body 7, and the pressure compensation plate 3 are all made of ceramics and other materials with high hardness, wear resistance, low friction coefficient, and high surface finish. The end surface friction coefficient is small, and the friction and shear force that the valve core 6 needs to overcome to open and slide is small, requiring less thrust from the drive device 1.

[0071] When the drive device 1 returns to its original position, the valve core 6 slides to the left under the action of the spring 9, closing the valve port (i.e., the first and second working gaps disappear). The forces acting on the upper and lower end surfaces of the valve core 6 remain the same as at the initial moment, and the oil inlet M and the oil outlet N are disconnected, completing one working cycle. The above operation is repeated to achieve continuous operation of the hydraulic valve.

[0072] The right side of the middle oil outlet groove n2 is the valve port of the valve core 6, or the projection of the valve port on the upper surface of the valve core 6 is an oblique line, a broken line or a curve.

[0073] The geometric curve of the valve port of the plate-type valve core 6 of the hydraulic valve described in this embodiment (the projection shape of the valve port on the upper surface of the valve core 6) can be designed from a straight line to various curves such as a slant line, a broken line, a special-shaped line, a function curve, etc., to change the valve port opening gradient, thereby changing the valve port opening flow gain.

[0074] The hydraulic valve described in this embodiment can be configured as different hydraulic valves depending on the positioning of the drive device 1. When the drive device 1 is a switch solenoid, the hydraulic valve described in this embodiment is a switch valve; when the drive device 1 is a proportional solenoid, the hydraulic valve described in this embodiment is a proportional valve; when the drive device 1 is a pilot stage valve, the hydraulic valve described in this embodiment is a servo valve, and so on. Furthermore, the hydraulic valve described in this embodiment can also serve as the pilot stage of other main valves, such as a servo valve.

[0075] A hydraulic valve described in an embodiment of the present application is provided with a pressure compensation device on the floating valve core 6, and the pressure compensation device is used to adjust the size and direction of the resultant force acting on the pressure compensation plate 3, so as to cause the pressure compensation plate 3 to move vertically downward and press the valve core 6, so that the gap between the valve core 6 and the lower valve body 7, and the valve core 6 and the pressure compensation plate 3 is smaller than the order of magnitude of the diameter of the pollutant particles, thereby preventing the entry of oil pollutants and particulate matter. At the same time, the compressed valve core is also less likely to be eccentric; it effectively solves the technical problem in the prior art that the valve core of the hydraulic valve is easily worn by pollutants and is prone to eccentric jamming during movement, so that the valve core 6 is not easily scratched, worn, or jammed by pollutants, and is not prone to eccentric jamming during movement, thereby achieving the technical effect of the hydraulic valve being durable and easy to use.

[0076] The above one or more technical solutions in the embodiments of the present application have at least one or more of the following technical effects:

[0077] A hydraulic valve described in an embodiment of the present application is configured to provide a pressure compensation plate on a floating valve core, and a pressure compensation device on the pressure compensation plate. The pressure compensation device is adjusted to cause the pressure compensation plate to move downward and press the valve core, so that an infinitely small gap can be achieved between the upper and lower end surfaces of the valve core, thereby preventing oil contaminants and particulate matter from entering the working gap. At the same time, the compressed valve core is also less likely to become eccentric. This effectively solves the technical problem in the prior art that the valve core of the hydraulic valve is easily worn by contaminants and is prone to eccentric jamming during movement, so that the valve core 6 is not easily scratched, worn, or jammed by contaminants and is not prone to eccentric jamming during movement, thereby achieving the technical effect of a durable and easy-to-use hydraulic valve.

[0078] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A hydraulic valve, characterized in that: The hydraulic valve comprises an upper valve body (2) and a lower valve body (7) fixedly connected to each other in an upper and lower manner, wherein a groove is provided on the lower surface of the upper valve body (2), and a pressure compensation plate (3) that can only move up and down is provided in the groove; an upwardly protruding boss is provided on the upper surface of the lower valve body (7), and a valve core (6) is provided between the boss and the pressure compensation plate (3), and one side of the valve core (6) is connected to a driving device (1) that drives the valve core (6) to move left and right, and the other side of the valve core (6) is connected to a reset device; A lower oil inlet groove (m1), a lower oil outlet groove (n1) and a lower low-pressure groove (t1) are respectively provided on the upper surface of the boss; a middle oil inlet groove (m2), a middle oil outlet groove (n2) and a middle and low-pressure hole (t2) are respectively provided on the valve core (6); an upper oil inlet groove (m3), an upper oil outlet groove (n3) and an upper low-pressure groove (t3) are respectively provided on the pressure compensation plate (3); the lower oil inlet groove (m1) and the upper oil inlet groove (m3) are symmetrically arranged in the upper and lower directions; the lower oil outlet groove (n1) and the upper oil outlet groove (n3) are symmetrically arranged in the upper and lower directions; the lower low-pressure groove (t1) and the upper low-pressure groove (t3) are symmetrically arranged in the upper and lower directions; the middle oil outlet groove (n2) and the middle oil inlet groove (m2) are spaced apart in the left and right directions, and the length of the middle oil outlet groove (n2) in the left and right directions is greater than the distance between the lower oil outlet groove (n1) and the lower oil inlet groove (m1); An oil inlet (M), an oil outlet (N) and an oil return port (T) are provided on the lower surface of the lower valve body (7); an oil inlet flow channel (m), an oil outlet flow channel (n) and a low-pressure flow channel (t) are respectively provided in the lower valve body (7); the lower oil inlet groove (m1) is communicated with the oil inlet (M) via the oil inlet flow channel (m); the lower oil outlet groove (n1) is communicated with the oil outlet (N) via the oil outlet flow channel (n); and the lower low-pressure groove (t1) is communicated with the oil return port (T) via the low-pressure flow channel (t); The lower oil inlet groove (m1), the middle oil inlet groove (m2) and the upper oil inlet groove (m3) are aligned up and down to form a high-pressure chamber (M0); the lower oil outlet groove (n1), the middle oil outlet groove (n2) and the upper oil outlet groove (n3) are aligned up and down to form a working chamber (N0); the lower low-pressure groove (t1), the middle and low-pressure holes (t2) and the upper low-pressure groove (t3) are aligned up and down to form a low-pressure chamber (T0); the high-pressure chamber (M0) is connected to the oil inlet port (M) via the oil inlet flow channel (m) to form an oil inlet channel; the working chamber (N0) is connected to the oil outlet port (N) via the oil outlet flow channel (n) to form an oil outlet channel; the low-pressure chamber (T0) is connected to the oil return port (T) via the low-pressure flow channel (t) to form an oil return channel; The pressure compensation plate (3) is provided with a plurality of upper low-pressure holes (t4), the bottom openings of the upper low-pressure holes (t4) extend into the upper low-pressure groove (t3) and are in communication with the upper low-pressure groove (t3), and the top openings of the upper low-pressure holes (t4) are located on the upper surface of the pressure compensation plate (3); The hydraulic valve further comprises a pressure compensating device, the pressure compensating device comprising a first mounting groove and a second mounting groove provided on the lower surface of the upper valve body (2), wherein the first mounting groove and the upper surface of the pressure compensating plate (3) enclose a first regulating chamber, and the second mounting groove and the upper surface of the pressure compensating plate (3) enclose a second regulating chamber; a first regulating piston (4) which can only move up and down is provided in the first regulating chamber, a second regulating piston (5) which can only move up and down is provided in the second regulating chamber, and a first sealing device is provided between the inner wall surface of the first regulating chamber and the outer peripheral surface of the first regulating piston (4), and a second sealing device is provided between the inner wall surface of the second regulating chamber and the outer peripheral surface of the second regulating piston (5); The upper valve body (2) is further provided with a first pressure regulating hole (U) for inputting high-pressure control oil to the upper part of the first regulating piston (4) in the first regulating chamber, and a second pressure regulating hole (V) for inputting working pressure control oil to the upper part of the second regulating piston (5) in the second regulating chamber; the bottom end of the first pressure regulating hole (U) is communicated with the bottom of the first mounting groove, the top end of the first pressure regulating hole (U) is located on the upper surface of the valve body (2) and is communicated with the oil outlet (N), the bottom end of the second pressure regulating hole (V) is communicated with the bottom of the second mounting groove, the top end of the second pressure regulating hole (V) is located on the upper surface of the valve body (2) and is communicated with the oil inlet (M); The valve core (6) is provided with a plurality of rectangular medium and low pressure holes (t2) arranged at intervals; The upper low-pressure hole (t4) corresponds to the middle low-pressure hole (t2) one by one.

2. A hydraulic valve according to claim 1, characterized in that: The projection of the lower oil outlet groove (n1) on the lower end surface of the valve core (6) is a first rectangle, and the projection of the lower oil inlet groove (m1) on the upper end surface of the valve core (6) is a second rectangle. The wide side of the first rectangle and the long side of the second rectangle are parallel and aligned, and the long side of the first rectangle and the wide side of the second rectangle are collinear.

3. A hydraulic valve according to claim 2, characterized in that: The lower oil inlet groove (m1) and the lower oil outlet groove (n1) are both rectangular grooves, and the lower oil inlet groove (m1) and the lower oil outlet groove (n1) are arranged at intervals on the left and right. The lower low-pressure groove (t1) is a rectangular annular groove surrounding the lower oil inlet groove (m1) and the lower oil outlet groove (n1).

4. A hydraulic valve according to claim 3, characterized in that: The upper oil inlet groove (m3) and the upper oil outlet groove (n3) are both rectangular grooves, and the upper oil inlet groove (m3) and the upper oil outlet groove (n3) are arranged at intervals, and the upper low-pressure groove (t3) is a rectangular annular groove surrounding the upper oil inlet groove (m3) and the upper oil outlet groove (n3).

5. A hydraulic valve according to claim 1, characterized in that: The reset device includes a spring and a spring pressure rod (11) extending horizontally from left to right, the left end of the spring pressure rod (11) penetrates between the pressure compensation plate (3) and the valve core (6), the left end of the spring pressure rod (11) is connected to a spring pressure head (8) through a spring (9), the spring (9) can be extended and retracted in the left and right directions, and the spring pressure head (8) is aligned with the right side of the valve core (6); a baffle (10) is fixed to the right side of the upper valve body (2) and the lower valve body (7), the right end of the spring pressure rod (11) penetrates the baffle (10), and the spring pressure rod (11) is threadedly connected to the baffle (10).

6. A hydraulic valve according to claim 1, characterized in that: The right side of the middle oil outlet groove (n2) is the valve port of the valve core (6), and the projection of the valve port on the upper surface of the valve core (6) is an oblique line, a broken line or a curve.

7. A hydraulic valve according to claim 1, characterized in that: The valve core (6) is circular, and the boss is cylindrical.

8. The hydraulic valve according to claim 1, characterized in that: The driving device is a switch electromagnet, a proportional electromagnet or a pilot valve.

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