A valve core and a proportional valve

Abstract

The utility model relates to a hydraulic technology field, concretely relates to a valve core and proportional valve. A valve core is slidably assembled in the valve body, and the valve core controls the on-off between the oil ports, the valve core includes the valve core body, the first shoulder portion, the second shoulder portion, the third shoulder portion and the fourth shoulder portion are set up on the valve core body along the axial direction, the first overflow groove, the second overflow groove and the third overflow groove are formed between the adjacent shoulder portions in proper order, the second overflow groove keeps the communication with the pressure oil port, the side of the second shoulder portion close to the third shoulder portion forms the full circumference opening, the pressure oil of pressure oil port introduction enters the first working oil port through the full circumference opening, the side of the fourth shoulder portion close to the third shoulder portion forms the involute unloading groove, and the second working oil port is communicated with the oil return port through the involute unloading groove. The technical problem that the valve port pressure loss of proportional valve in the prior art is big, and the pressure impact is easily caused in the differential mode and the work mode switching process is solved.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic technology, specifically to a valve core and a proportional valve. Background Technology

[0002] In hydraulic control systems, proportional valves adjust the valve opening by axial displacement of the valve core, and are key components for achieving precise control of fluid direction and flow.

[0003] Existing technology utilizes the relative displacement between the valve core shoulder and the valve body groove to achieve the switching function between differential extension (rapid idle stroke) and working mode (load output) of an asymmetric hydraulic cylinder. However, practical applications have the following drawbacks:

[0004] (1) Large pressure loss: During the differential stage, when the pump outlet flow and the return oil from the rod chamber of the hydraulic cylinder flow through the valve port, a significant pressure loss occurs at the valve port of the rodless chamber, reducing the system energy efficiency.

[0005] (2) Switching shock: When the differential feed switches, the high pressure oil in the rod chamber is released instantaneously through the large gradient valve port, causing a pressure shock, which leads to a sudden change in the speed of the hydraulic cylinder, affecting the smoothness of operation, positioning accuracy and component life.

[0006] To address these shortcomings, a valve core and proportional valve were designed to reduce valve orifice pressure drop and improve switching stability. Utility Model Content

[0007] To address the technical problems of large pressure loss at the valve orifice in existing proportional valves and the tendency to cause pressure shocks during the switching between differential and working modes, this invention provides a valve core and a proportional valve that solve the aforementioned technical problems.

[0008] To solve the above-mentioned technical problems, this utility model provides a valve core that is slidably assembled in a valve body. The valve body is provided with a pressure oil port, two working oil ports, and a return oil port. The valve core slides to control the on / off state between the oil ports. The valve core includes a valve core body. The valve core body is provided with a first shoulder, a second shoulder, a third shoulder, and a fourth shoulder along the axial direction. A first flow groove, a second flow groove, and a third flow groove are formed sequentially between adjacent shoulders. The second flow groove is kept in communication with the pressure oil port. A full-circumferential opening is formed on the side of the second shoulder near the third shoulder. The pressure oil introduced by the pressure oil port enters the first working oil port through the full-circumferential opening. An involute unloading groove is formed on the side of the fourth shoulder near the third shoulder. The second working oil port is connected to the return oil port through the involute unloading groove.

[0009] According to one embodiment of the present invention, a first throttling window is provided on the side of the second shoulder away from the third shoulder.

[0010] According to one embodiment of the present invention, a second throttling window and a third throttling window are respectively provided on both sides of the third shoulder, and the third throttling window is disposed opposite to the involute unloading groove.

[0011] According to one embodiment of the present invention, the axial length of the first flow channel is greater than the axial length of the third flow channel.

[0012] This utility model also provides a proportional valve, comprising:

[0013] Valve body, wherein a mounting hole is formed in the valve body;

[0014] The valve core is slidably assembled within the mounting hole.

[0015] According to one embodiment of the present invention, the pressure port is connected to the pressure chamber, the first working port is connected to the first working chamber, the second working port is connected to the second working chamber, the return port is connected to the return chamber, the pressure chamber, the two working chambers and the return chamber are all connected to the mounting hole, the two working chambers are arranged on both sides of the pressure chamber, and there are two return chambers, which are located on the outside of the two working chambers respectively.

[0016] According to one embodiment of the present invention, in the initial state, the second shoulder and the third shoulder respectively seal the first working chamber and the second working chamber, one oil return chamber is connected to the first flow channel, the other oil return chamber is connected to the third flow channel for throttling, and the pressure chamber is connected to the second flow channel.

[0017] According to one embodiment of the present invention, in the initial state, the axial length of the connection between the oil return chamber and the third flow channel is n, and the axial distance d between the second working chamber and the third shoulder for unsealing is less than n.

[0018] According to one embodiment of the present invention, a valve body control edge is formed on the opening of the return oil chamber corresponding to the third flow channel, facing the involute unloading channel.

[0019] According to one embodiment of the present invention, it further includes a connecting oil passage, which is used to connect the second working chamber and the pressure chamber, and the oil in the second working chamber flows unidirectionally to the pressure chamber through the connecting oil passage.

[0020] Based on the above technical solution, the technical effects that this utility model can achieve are as follows:

[0021] The valve core of this invention enables the differential extension and working load functions of the actuator. In differential mode, the oil in the second working port can flow to the pressure port, merge with the pump flow of the pressure port, and then enter the first working port through a full-circumferential opening, realizing the differential extension of the hydraulic cylinder. Using a full-circumferential opening instead of a partial throttling groove significantly reduces the merging pressure loss and energy consumption. An involute unloading groove is added to the fourth shoulder, so that when switching from differential mode to working mode, the oil in the second working port can flow to the return port through the involute unloading groove, achieving a slow release of pressure in the second working port, suppressing hydraulic shock, and ensuring a smooth switching speed.

[0022] The proportional valve of this utility model has a valve core assembled in the valve body, which can realize differential mode. In differential mode, the pressure oil port is connected to the first working oil port through the second flow groove, and the fourth shoulder blocks the connection between the second working oil port and the return oil port. The pressure oil of the second working oil port flows unidirectionally through the connecting oil passage to merge with the pressure oil of the pressure oil port and then enters the first working oil port through the full circumferential opening, realizing the differential extension of the hydraulic cylinder. In working mode, the pressure oil port is connected to the first working oil port through the second flow groove, and the second working oil port is connected to the return oil port through the third flow groove, realizing oil inlet at the first working oil port and oil return at the second working oil port.

[0023] The proportional valve of this utility model, by reasonably setting the relationship between the axial length n of the connection port from the return oil chamber to the third flow groove and the axial distance d between the second working chamber and the third shoulder for unsealing, can realize the working mode when the valve core sliding distance is less than n and greater than d; and can realize the differential mode when the valve core sliding distance is greater than n. That is, the differential mode and the working mode can be switched by controlling the sliding distance of the valve core. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the valve core structure of this utility model;

[0025] Figure 2 This is the front view of the valve core;

[0026] Figure 3 This is a cross-sectional view of a proportional valve.

[0027] Figure 4 This refers to the state of the valve core within the valve body in differential mode.

[0028] Figure 5 This is a diagram showing the slow release of pressure guided by the involute unloading groove during the transition from differential mode to working mode.

[0029] In the diagram: 1-Valve core; 11-Valve core body; 12-First shoulder; 13-Second shoulder; 131-Full circumferential opening; 132-First throttling window; 14-Third shoulder; 141-Second throttling window; 142-Third throttling window; 15-Fourth shoulder; 151-Involute unloading groove; 16-First flow groove; 17-Second flow groove; 18-Third flow groove; 2-Valve body; 21-Mounting hole; 22-Pressure chamber; 231-First working chamber; 232-Second working chamber; 241-First return oil chamber; 242-Second return oil chamber; 25-Valve body control edge. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0031] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0032] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0033] In the description of this utility model, it should be understood that the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself.

[0034] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0035] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0036] like Figure 1-2 As shown, this embodiment provides a valve core 1, including a valve core body 11. The valve core body 11 is provided with multiple shoulders, and a flow groove is formed between adjacent shoulders. The valve core 1 is slidably assembled in the valve body 2, and the opening and closing of the oil port in the valve body 2 is controlled by the shoulders and the flow groove.

[0037] like Figure 1-2 As shown, the valve core body 11 is an axially extending shaft structure. The valve core body 11 is provided with a first shoulder 12, a second shoulder 13, a third shoulder 14 and a fourth shoulder 15 spaced apart along the axial direction. A first flow groove 16 is formed between the first shoulder 12 and the second shoulder 13, a second flow groove 17 is formed between the second shoulder 13 and the third shoulder 14, and a third flow groove 18 is formed between the third shoulder 14 and the fourth shoulder 15.

[0038] As a preferred embodiment, a full-circumferential opening 131 is formed on the side of the second shoulder 13 near the third shoulder 14. During use, the valve core 1's second flow groove 17 is connected to the pressure oil port, allowing the pressurized oil from the pressure oil port to enter a working oil port through the full-circumferential opening 131, thus reducing pressure loss. A first throttling window 132 is provided on the side of the second shoulder 13 away from the third shoulder 14.

[0039] As a preferred technical solution of this embodiment, throttling windows are respectively provided on both sides of the third shoulder 14. Specifically, a second throttling window 141 is provided on the side of the third shoulder 14 closer to the second shoulder 13, and a third throttling window 142 is provided on the other side of the third shoulder 14.

[0040] As a preferred technical solution in this embodiment, such as Figure 1 As shown, an involute unloading groove 151 is provided on the side of the fourth shoulder 15 near the third shoulder 14, and the involute unloading groove 151 is disposed opposite to the third throttling window 142. Specifically, the involute unloading groove 151 can be configured as an arc-shaped stepped groove. When the valve core 1 is assembled in the valve body, the involute unloading groove 151 controls the throttling return oil of the other working oil port.

[0041] As a preferred technical solution in this embodiment, the axial length of the first flow channel 16 is greater than the axial length of the third flow channel 18.

[0042] like Figure 3-5 As shown, this embodiment also provides a proportional valve, including a valve core 1 and a valve body 2. The valve body 2 has a mounting hole 21, and the valve body 2 is provided with a pressure oil port, two working oil ports and a return oil port. The valve core 1 is slidably assembled in the mounting hole 21, and the sliding control controls the on / off state between the oil ports.

[0043] Specifically, the pressure port on valve body 2 is connected to pressure chamber 22, the two working ports are connected to the two working chambers respectively, and the return port is connected to the return chamber. Pressure chamber 22, the two working chambers and the return chamber are connected to mounting hole 21 respectively. The pressure port is used to introduce pressure oil, the two working ports are connected to the two cavities of the actuator (such as a hydraulic cylinder) respectively, and the return port is connected to the oil tank.

[0044] As a preferred embodiment, the two working ports are a first working port and a second working port. The first working port connects to the first working chamber 231, and the second working port connects to the second working chamber 232. The first working chamber 231 and the second working chamber 232 are arranged on both sides of the pressure chamber 22. Preferably, the first working chamber 231 and the second working chamber 232 are symmetrically arranged on both sides of the pressure chamber 22.

[0045] As a preferred embodiment, two oil return chambers are provided, namely a first oil return chamber 241 and a second oil return chamber 242. The first oil return chamber 241 and the second oil return chamber 242 are connected by an internal oil passage and are located outside the two working chambers. Preferably, the first oil return chamber 241 is located outside the first working chamber 231, and the second oil return chamber 242 is located outside the second working chamber 232. Preferably, the first oil return chamber 241 and the second oil return chamber 242 are symmetrically arranged on both sides of the pressure chamber 22.

[0046] Valve core 1 slides to control the opening and closing of the pressure chamber 22, the working chamber, and the return oil chamber. For example... Figure 3 As shown, in the initial state, valve core 1 is in the neutral position, second shoulder 13 seals first working chamber 231, third shoulder 14 seals second working chamber 232; second flow groove 17 is connected to pressure chamber 22, first flow groove 16 is connected to first return oil chamber 241; third flow groove 18 is throttled connected to second return oil chamber 242.

[0047] As a preferred embodiment, a valve body control edge 25 is formed at the connection between the second return oil chamber 242 on the valve body 2 and the mounting hole 21, facing the involute unloading groove 151. Preferably, valve body control edges can also be formed on both axial sides of the pressure chamber 22 and both axial sides of the two working chambers.

[0048] As a preferred embodiment, the axial length of the connection port between the third flow channel 18 and the second oil return chamber 242 is n, such as... Figure 3 As shown, the maximum axial distance from the involute unloading groove 151 to the valve body control edge 25 is n; the axial distance for releasing the seal between the second working chamber 232 and the third shoulder 14 is d, that is, the minimum axial distance from the third throttling window 142 to the second working chamber 232 is d, where d is less than n. Thus, as... Figure 3 At the position shown, when the valve core 1 moves to the left a distance greater than d and less than n, the second working chamber 232 is connected to the second return oil chamber 242 through the third flow groove 18; when the valve core 1 moves to the left a distance greater than n, the third flow groove 18 is connected to the second working chamber 232, while the fourth shoulder 15 blocks the second return oil chamber 242.

[0049] The proportional valve in this embodiment also includes a connecting oil passage, which connects the second working chamber 232 and the pressure chamber 22. The oil in the second working chamber 232 can flow unidirectionally to the pressure chamber 22 through the connecting oil passage. Specifically, a check valve can be installed on the connecting oil passage to control the flow direction of the oil.

[0050] Based on the above technical solution, when the proportional valve of this embodiment is used in a hydraulic cylinder, it can connect the first working port to the rodless chamber of the hydraulic cylinder and the second working port to the rod chamber of the hydraulic cylinder. The working principle is as follows:

[0051] like Figure 3 As shown, in the initial state, valve core 1 is in the middle position, second shoulder 13 seals first working chamber 231, third shoulder 14 seals second working chamber 232, and there is no communication between the chambers.

[0052] like Figure 4 As shown, during differential extension, the valve core 1 moves to the left by a distance greater than n. The pressure chamber 22 connects to the first working chamber 231 via the second flow groove 17. The fourth shoulder 15 seals the second return oil chamber 242. The oil in the second working chamber 232 flows to the pressure chamber 22 via the connecting oil passage. After merging with the pressure oil in the pressure chamber 22, it enters the first working chamber 231 through the full circumferential opening 131. That is, the oil in the rod chamber of the hydraulic cylinder merges with the pump flow and enters the rodless chamber, realizing the differential extension of the hydraulic cylinder.

[0053] like Figure 5 As shown, during differential feed switching, the valve core 1 moves left by a distance greater than d and less than n. The pressure chamber 22 connects to the first working chamber 231 via the second flow groove 17. The fourth shoulder 15 separates from the valve body control edge 25, and the second working chamber 232 connects to the second return oil chamber 242 via the third flow groove 18, allowing oil return from the second working chamber 232. Due to the setting of the third throttling window 142 and the cooperation between the involute unloading groove 151 and the valve body control edge 25, the large opening design of the full circumferential opening 131 ensures efficient pressure transmission to the rodless chamber of the hydraulic cylinder even with a small opening, improving the load driving capability.

[0054] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A valve core, slidably assembled within a valve body (2), wherein the valve body (2) is provided with a pressure port, two working ports and a return port, and the valve core (1) slidably controls the opening and closing of the ports, characterized in that, The valve core (1) includes a valve core body (11). The valve core body (11) is provided with a first shoulder (12), a second shoulder (13), a third shoulder (14) and a fourth shoulder (15) along the axial direction. A first flow groove (16), a second flow groove (17) and a third flow groove (18) are formed between adjacent shoulders in sequence. The second flow groove (17) is connected to the pressure port. A full circumferential opening (131) is formed on the side of the second shoulder (13) near the third shoulder (14). The pressure oil introduced by the pressure port enters the first working port through the full circumferential opening (131). An involute unloading groove (151) is formed on the side of the fourth shoulder (15) near the third shoulder (14). The second working port is connected to the return port through the involute unloading groove (151).

2. A valve core according to claim 1, characterized in that, A first throttling window (132) is provided on the side of the second shoulder (13) away from the third shoulder (14).

3. A valve core according to claim 1, characterized in that, The third shoulder (14) is provided with a second throttling window (141) and a third throttling window (142) on both sides, and the third throttling window (142) is arranged opposite to the involute unloading groove (151).

4. A valve core according to claim 1, characterized in that, The axial length of the first flow channel (16) is greater than the axial length of the third flow channel (18).

5. A proportional valve, characterized in that, include: Valve body (2), wherein a mounting hole (21) is formed in the valve body (2); The valve core (1) according to any one of claims 1-4, wherein the valve core (1) is slidably fitted into the mounting hole (21).

6. A proportional valve according to claim 5, characterized in that, The pressure port is connected to the pressure chamber (22), the first working port is connected to the first working chamber (231), the second working port is connected to the second working chamber (232), and the return port is connected to the return chamber. The pressure chamber (22), the two working chambers and the return chamber are all connected to the mounting hole (21). The two working chambers are arranged on both sides of the pressure chamber (22), and there are two return chambers, which are located on the outside of the two working chambers respectively.

7. A proportional valve according to claim 6, characterized in that, In the initial state, the second shoulder (13) and the third shoulder (14) respectively seal the first working chamber (231) and the second working chamber (232), one oil return chamber is connected to the first flow channel (16), the other oil return chamber is connected to the third flow channel (18) for throttling, and the pressure chamber (22) is connected to the second flow channel (17).

8. A proportional valve according to claim 7, characterized in that, In the initial state, the axial length of the connection between the oil return chamber and the third flow channel (18) is n, and the axial distance d between the second working chamber (232) and the third shoulder (14) for unsealing is less than n.

9. A proportional valve according to claim 7, characterized in that, A valve body control edge (25) is formed on the opening of the return oil chamber corresponding to the third flow channel (18) facing the involute unloading channel (151).

10. A proportional valve according to claim 6, characterized in that, It also includes a connecting oil passage, which is used to connect the second working chamber (232) and the pressure chamber (22), and the oil in the second working chamber (232) flows unidirectionally to the pressure chamber (22) through the connecting oil passage.

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