Valve element and hydraulic valve

Abstract

The hydraulic valve comprises a valve seat, and the valve element comprises a valve rod, a valve core, a valve core and a valve core body, the step part is arranged at the end part of the valve rod, and the valve rod and the step part are inserted into the valve seat; one end of the step part is connected with the valve rod, the other end of the step part is connected with the abutting part, the abutting part is suitable for abutting against a valve port of the valve seat so as to block the valve port, and when the valve element moves in the extending direction from the valve rod to the abutting part, the abutting part is suitable for abutting against the valve port of the valve seat so as to block the valve port of the valve seat. And the opening area of the valve port is gradually increased along with the increase of the displacement of the valve core. The hydraulic valve core provided by the embodiment of the utility model not only can realize reliable cone sealing, but also can improve the control precision of the cone valve core on the flow and improve the stability of the hydraulic valve on the basis of a large-flow specification valve core.

Description

Technical Field

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

[0002] In the field of engineering machinery, the transmission mode of most working mechanisms is hydraulic transmission, that is, the engine drives the hydraulic pump to provide hydraulic energy, and the hydraulic control valve provides the hydraulic cylinder or hydraulic motor with flow and maximum pressure to support the action, thereby completing the action of the mechanical equipment.

[0003] In hydraulic control valves, the valve opening is controlled by the action of the valve core, thereby controlling the flow rate of the valve port. In order to meet the requirements of the host equipment, the valve port flow gain requirements are different when the valve core is displaced at different times. In order to prevent the valve core from getting stuck with the valve seat, the cone valve core of the existing hydraulic valve generally has a larger semi-cone angle, and the step portion is mostly a one-stage structure, which is relatively simple in terms of flow control. Under high-pressure and low-flow conditions, the low-speed control micro-motion of the valve is poor and difficult to accurately control; when working at a large flow rate, the pressure loss is large.

[0004] Therefore, there is an urgent need to provide a valve core and a hydraulic valve for a hydraulic valve, which can realize multi-stage control of flow rate and improve the accuracy of low-speed micro-movement and the stability of hydraulic valve use under conditions suitable for large flow rates. Utility Model Content

[0005] The technical problem solved by the utility model is to provide a valve core and a hydraulic valve, which can realize multi-stage control of flow rate and improve the control accuracy and stability of the use of the hydraulic valve in a large flow working scenario.

[0006] To solve the above technical problems, an embodiment of the utility model provides a valve core for a hydraulic valve, the hydraulic valve including a valve seat, characterized in that the valve core includes: a valve stem; a step portion, the step portion is arranged at the end of the valve stem, the valve stem and the step portion are inserted in the valve seat; an abutment portion, one end of the step portion is connected to the valve stem, and the other end of the step portion is connected to the abutment portion, the abutment portion is suitable for abutting against the valve port of the valve seat to block the valve port, when the valve core moves along the extension direction from the valve stem to the abutment portion, the opening area of ​​the valve port gradually increases with the increase of the displacement of the valve core.

[0007] Optionally, the step portion includes n frustums connected in sequence, where n is a natural number greater than 1, and each of the frustums includes a first end and a second end, wherein the first end of the 1st frustum is connected to the valve stem, the second end of the i-th frustum is connected to the first end of the i+1-th frustum, and the second end of the n-th frustum is connected to the abutment portion, 1≤i<n.

[0008] Optionally, the angle α between the generatrix of the i-th cone and the axis of the valve core is i The angle is greater than the angle α between the generatrix of the i+1th truncated cone and the axis of the valve core i+1 angle.

[0009] Optionally, the angle α between the generatrix of the nth truncated cone and the axis of the valve core is n An angle that is smaller than the angle θ between the generatrix of the abutment portion and the axis of the valve core.

[0010] Optionally, the step portion is formed by rotating a curved trapezoid around its right-angle waist, and the curved side of the curved trapezoid is a convex arc.

[0011] Optionally, along the extension direction from the valve stem to the abutting portion, an angle β between the tangent line at each point on the convex circular arc and the axis of the valve core gradually decreases.

[0012] Optionally, the angle β between the tangent line of the end point where the convex arc is connected to the abutment portion and the axis of the valve core is n The angle is smaller than the angle θ between the generatrix of the abutting portion and the axis of the valve core.

[0013] Optional, 2°≤α n ≤8°.

[0014] Optionally, 10°≤θ≤20°.

[0015] Optionally, the valve stem is a cylindrical structure, and the abutting portion is a truncated cone structure.

[0016] The embodiment of the utility model further provides a hydraulic valve, comprising the valve core described above, wherein the valve core is installed in the valve seat.

[0017] Compared with the prior art, the technical solution of the embodiment of the utility model has the following beneficial effects:

[0018] The hydraulic valve core provided by the present technical solution has an abutment portion that can achieve reliable conical sealing and will not be stuck by the valve seat. During operation, the opening area of ​​the valve port gradually increases as the displacement of the valve core increases. In the initial stage of opening the hydraulic valve core, the effective opening of the valve port is small under unit axial displacement of the valve core, so the liquid flow passing through is small, which is beneficial to improving the control accuracy of the hydraulic valve over the flow rate and can improve the stability of the valve core when starting. As the displacement of the valve core increases, the opening area of ​​the valve port gradually increases further. Under unit axial displacement of the valve core, the effective opening of the valve port increases, and the hydraulic valve can achieve a flow capacity with a larger flow specification.

[0019] Further, the step portion includes n frustums connected in sequence, n is a natural number greater than 1, and each frustum includes a first end and a second end, wherein the first end of the first frustum is connected to the valve stem, the second end of the i-th frustum is connected to the first end of the i+1-th frustum, and the second end of the n-th frustum is connected to the abutment portion, 1≤i<n. The step portion includes n frustums, and as the valve core is displaced, the vertical distance between each frustum and the valve port is different, so that the opening area of ​​the valve port is different, thereby realizing segmented control of the liquid flow through the valve port, which is conducive to being applicable to different working conditions.

[0020] Furthermore, the angle α between the generatrix of the i-th cone and the axis of the valve core is i The angle is greater than the angle α between the generatrix of the i+1th truncated cone and the axis of the valve core i+1 In the initial stage of valve core opening, the opening area of ​​the valve port increases slowly with the increase of valve core displacement, and the flow gain is small, which can improve the control accuracy of the flow and improve the stability of the valve core when starting. In the later stage, the opening area of ​​the valve port increases rapidly with the increase of valve core displacement, which can meet the use requirements of large flow in the later stage.

[0021] The hydraulic valve provided by the present technical solution adopts a valve core with a segmented cone, thereby realizing segmented control of the flow rate, which can be more suitable for different working conditions, and can improve the precise control of the flow rate at the initial opening stage in a large flow working scenario, and improve the stability during startup. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of the valve core in one embodiment of the utility model;

[0023] Figure 2 It is a schematic diagram of the cross-sectional structure of the valve core step portion and the abutment portion in one embodiment of the utility model;

[0024] Figure 3 It is a schematic cross-sectional structure diagram of a valve core step portion and an abutting portion in another embodiment of the utility model. DETAILED DESCRIPTION

[0025] As described in the background technology, in order to meet the requirements of the host equipment, the valve port flow gain requirements are different at different valve core displacements. For example, when the valve core displacement initially moves, the actuator is required to move very slowly, and the micro-motion requirements are high; in the middle stage of the valve core position, a moderate valve port area change rate is required to match the host action; but when the valve core displacement has a large stroke, a very large flow specification is required to reduce pressure loss. At present, there are cases where sliding valves are realized by machining grooves, but the machining is difficult, and there is a shaft hole gap when the valve port is closed, resulting in large leakage, and it cannot be closed reliably, especially under load-holding conditions. In general, during the use of a cone valve, the opening of the cone valve port can be adjusted by displacing the valve core, thereby controlling the flow rate to obtain different speeds, but the current cone valve core angle is single. In order to prevent the valve core and the valve seat from getting stuck, the semi-cone angle of the cone valve core of the existing hydraulic valve is generally large, and the step part is mostly a one-stage structure. The flow control is relatively simple. Under high pressure and low flow conditions, the valve port area change rate per unit valve core displacement is large, the low-speed control micro-motion of the valve is poor, and it is difficult to control accurately; and when working at a large flow, the pressure loss is also large.

[0026] In order to solve the above problems, an embodiment of the utility model provides a valve core of a hydraulic valve and a hydraulic valve, wherein the valve core includes a valve stem, a step portion and an abutment portion, the abutment portion can achieve reliable sealing with the valve port and will not be stuck by the valve seat, when the valve core is working, the opening area of ​​the valve port gradually increases with the increase of the displacement of the valve core, in the initial stage of the valve core opening, the flow through the valve port is small, with the axial displacement of the valve core, the flow through the valve port gradually increases, in the large flow working scenario, it is conducive to the smooth opening of the hydraulic valve, and is conducive to achieving the effect of precise control of small flow, further improving the micro-motion of the control equipment.

[0027] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] Figure 1 It is a structural schematic diagram of the valve core in one embodiment of the utility model. Figure 2 It is a schematic diagram of the cross-sectional structure of the valve core in one embodiment of the utility model; Figure 3 It is a schematic cross-sectional structure diagram of a valve core in another embodiment of the utility model.

[0029] Reference Combined with reference Figure 1 and Figure 2The hydraulic valve includes a valve core 10 and a valve seat 20, wherein the valve core 10 is installed in the valve seat 20, and the valve seat 20 has a valve port. The valve core 10 includes: a valve stem 11; a step portion 12, wherein the step portion 12 is arranged at the end of the valve stem 11, and the valve stem 11 and the step portion 12 are inserted in the valve seat 20, and the step portion 12 is suitable for controlling the opening area of ​​the valve port; an abutment portion 13, wherein one end of the step portion 12 is connected to the valve stem 11, and the other end is connected to the abutment portion 13, and the abutment portion 13 is suitable for abutting against the valve port to block the valve port. When the valve core 10 moves along the extension direction from the valve stem 11 to the abutment portion 13, the opening area of ​​the valve port gradually increases as the displacement of the valve core 10 increases.

[0030] In this embodiment, the valve core 10 further includes a piston end 14 , and one end of the valve stem 11 is connected to the step portion 12 , and the other end is connected to the piston end 14 .

[0031] refer to Figure 2 In this embodiment, the step portion 12 includes n truncated cones 120 connected in sequence, where n is a natural number greater than 1.

[0032] In this embodiment, by providing a step portion 12 including a plurality of cones 120, when the cones 120 pass through the valve port in sequence, the opening area of ​​the valve port can be controlled according to the different vertical distances between the valve port angle 201 and the curved surfaces of different cones 120, thereby controlling the flow rate of the oil passing through the valve port, thereby achieving the effect of segmented flow control, and the opening area of ​​the valve port gradually increases with the increase of the displacement of the valve core 10. In the initial stage of the valve core opening, the valve port opening is small and the oil flow rate is small, which is conducive to smooth starting. In the later stage of the valve core opening, the flow rate gradually increases, which can be applied to large flow conditions.

[0033] In this embodiment, the valve stem 11 is a cylindrical structure, and the abutting portion 13 is a truncated cone structure.

[0034] In this embodiment, the extension direction from the valve stem 11 to the abutting portion 13 is X. When the valve core 10 moves along the X direction, the valve port gradually opens. When the valve core 10 moves in the opposite direction of X, the valve port gradually closes.

[0035] In this embodiment, the maximum diameter of the step portion 12 is less than or equal to the diameter of the valve port, and there is a gap between the step portion 12 and the valve port, and the gap is used to pass oil. Under a fixed pressure difference of the valve port, the flow rate of the oil passing through is determined by the opening area of ​​the valve port, that is, by the size of the gap between the step portion 12 and the valve port. Since the step portion 12 includes n truncated cones 120, the maximum diameters of the truncated cones 120 are not equal, that is, the sizes of the gaps between the truncated cones 120 and the valve port are not equal, so that the flow rate of the oil passing through the valve port can be adjusted.

[0036] In this embodiment, each of the frustums 120 includes a first end and a second end, wherein the first end of the first frustum is connected to the valve stem 11, the second end of the i-th frustum is connected to the first end of the i+1-th frustum, and the second end of the n-th frustum is connected to the abutment portion, 1≤i<n.

[0037] Specifically, along the X direction, the 1st frustum, ..., the ith frustum, the (i+1)th frustum, ..., and the nth frustum are connected in sequence.

[0038] Continue to refer Figure 2 In this embodiment, the angle α between the generatrix of the i-th cone and the axis of the valve core 10 is i The angle is greater than the angle α between the generatrix of the i+1th truncated cone and the axis of the valve core 10 i+1 angle.

[0039] Specifically, it can be considered that the slope of the generatrix of the i-th frustum is greater than the slope of the generatrix of the i+1-th frustum.

[0040] In this embodiment, α i The angle is greater than α i+1 The angle indicates that when the valve core 10 moves along the X direction, the increment of the opening area of ​​the valve port gradually increases with the movement of the valve core. In the initial stage of the valve core opening, due to the α n The cone angle is relatively small. Under the unit axial displacement of the valve core, the effective opening of the valve port is small, so the liquid flow through the valve port is small, and the flow rate increases slowly, which can improve the precise control of the flow rate, thereby improving the stability of the valve core when starting. With the increase of the valve core displacement, the valve port opening area gradually increases, and α i The taper becomes larger. Under the unit axial displacement of the valve core, the effective opening of the valve port becomes larger, and the flow rate increases rapidly with the movement of the valve core, which can meet the use requirements of large flow in the later stage.

[0041] In other embodiments, α may not be limited. i The angle and α i+1 The size relationship of the angle.

[0042] Furthermore, the angle α between the generatrix of the nth truncated cone and the axis of the valve core 10 is n The angle is smaller than the angle θ between the generatrix of the abutting portion 13 and the axis of the valve core 10 .

[0043] In this embodiment, in order to make the control angle of the valve port more precise, θ>α n ≥0°, α nThe angle of is smaller than the angle of θ, so that the abutting portion 13 and the valve port have a suitable angle when they are in contact with each other, forming a better seal, and in order to form a stable and reliable seal at the valve port, the valve port must be in contact with the abutting portion 13, and the angle of θ cannot be too small, which can avoid the situation where the abutting portion 13 is mechanically squeezed and stuck into the valve port due to the small angle of θ, so that the valve core 10 has better movement flexibility and better contact strength, ensuring contact stiffness.

[0044] Furthermore, 2°≤α n ≤8°, so that the flow rate of the hydraulic valve increases slowly at the initial opening stage, making the opening of the hydraulic valve more stable.

[0045] Furthermore, 10°≤θ≤20, so that the abutment portion 13 and the valve port abut to form a good seal, and avoid the abutment portion 13 being stuck in the valve port due to the angle θ being too small.

[0046] Continue to refer Figure 2 In this embodiment, n is taken as 2 for specific description. At this time, the value of i is 1. The cone 120 includes a first cone 121 and a second cone 122. The first end of the first cone 121 is connected to the valve stem 11, the second end of the first cone 121 is connected to the first end of the second cone 122, and the second end of the second cone 122 is connected to the abutment portion 13.

[0047] In this embodiment, the angle α1 between the generatrix of the first truncated cone 121 and the axis of the valve core 10 is greater than the angle α2 between the generatrix of the second truncated cone 122 and the axis of the valve core 10 .

[0048] In this embodiment, the angle α2 between the generatrix of the second truncated cone 122 and the axis of the valve core 10 is smaller than the angle θ between the generatrix of the abutting portion 13 and the axis of the valve core 10 .

[0049] In this embodiment, the angle of θ is 15°, and the angle of α2 is 5°.

[0050] refer to Figure 3 In another embodiment, the step portion 12 is formed by a curved trapezoid rotating around its right-angled waist 101, wherein the curved side 102 of the curved trapezoid is a convex arc.

[0051] In this embodiment, along the extension direction X from the valve stem 11 to the abutment portion 13, the angle β between the tangent line at each point on the convex arc and the axis of the valve core 10 gradually decreases, that is, the slope of the tangent line at each point on the convex arc gradually decreases.

[0052] By setting a step portion with a convex arc side, the curved edge can fit the valve port flow gain curve required by the design. When the valve core 10 moves along the X direction, the increment of the opening area of ​​the valve port gradually increases with the displacement of the valve core 10, and as the valve core 10 moves, the change of the opening area of ​​the valve port is softer.

[0053] Furthermore, the angle β between the tangent line of the end point 103 connecting the convex arc and the abutment portion 13 and the axis of the valve core 10 is n The angle is smaller than or equal to the angle θ between the generatrix of the abutting portion 13 and the axis of the valve core 10 .

[0054] The embodiment of the utility model further provides a hydraulic valve, comprising the valve core 10 described in any one of the above embodiments, wherein the valve core 10 is installed in the valve seat 20 .

[0055] Although the utility model is disclosed as above, the utility model is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model. Therefore, the protection scope of the utility model shall be subject to the scope defined by the claims.

Claims

1. A valve core for a hydraulic valve, the hydraulic valve comprising a valve seat, characterized in that: The valve core comprises: Valve stem; a step portion, the step portion being arranged at an end portion of the valve stem, the valve stem and the step portion being inserted into the valve seat; Abutment portion, one end of the step portion is connected to the valve stem, and the other end of the step portion is connected to the abutment portion, the abutment portion is suitable for abutting against the valve port of the valve seat to block the valve port, when the valve core moves along the extension direction from the valve stem to the abutment portion, the opening area of ​​the valve port gradually increases as the displacement of the valve core increases.

2. The valve core according to claim 1, characterized in that: The step portion includes n frustums connected in sequence, where n is a natural number greater than 1, and each of the frustums includes a first end and a second end, wherein the first end of the first frustum is connected to the valve stem, the second end of the i-th frustum is connected to the first end of the i+1-th frustum, and the second end of the n-th frustum is connected to the abutting portion, 1≤i<n.

3. The valve core according to claim 2, characterized in that: The angle α between the generatrix of the i-th cone and the axis of the valve core i The angle is greater than the angle α between the generatrix of the i+1th truncated cone and the axis of the valve core i+1 angle.

4. The valve core according to claim 3, characterized in that: The angle α between the generatrix of the nth truncated cone and the axis of the valve core n An angle that is smaller than the angle θ between the generatrix of the abutment portion and the axis of the valve core.

5. The valve core according to claim 1, characterized in that: The step portion is formed by a curved trapezoid rotating around its right-angle waist, and the curved side of the curved trapezoid is a convex arc.

6. The valve core according to claim 5, characterized in that: Along the extension direction of the valve stem to the abutting portion, the angle β between the tangent line of each point on the convex circular arc and the axis of the valve core gradually decreases.

7. The valve core according to claim 6, characterized in that: The angle β between the tangent line of the end point of the convex arc connected to the abutment portion and the axis of the valve core n The angle is less than or equal to the angle θ between the generatrix of the abutting portion and the axis of the valve core.

8. The valve core according to claim 4, characterized in that: 2°≤α n ≤8°。 9. The valve core according to claim 4 or 7, characterized in that: 10°≤θ≤20°.

10. The valve core according to claim 1, characterized in that: The valve stem is a cylindrical structure, and the abutting portion is a truncated cone structure.

11. A hydraulic valve, characterized in that: The valve core comprises the valve core according to any one of claims 1 to 10, wherein the valve core is installed in the valve seat.

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