A hydraulic lift valve with throttling control function and a hydraulic system

Abstract

This invention provides a hydraulically controlled lift valve and hydraulic system with throttling control function. The hydraulically controlled lift valve includes a first connection port, a second connection port, an unloading valve, a main control valve, and a logic valve. When the main control valve is in the neutral position, the first connection port is connected to the unloading valve through the main control valve, and the second connection port is locked. When the main control valve is in the lifting position, the first connection port is connected to the second connection port, and the unloading valve is closed. When the main control valve is in the lowering position, the unloading valve can be opened. The valve core of the main control valve has a fixed throttling orifice and a variable throttling groove. This hydraulically controlled lift valve enables the load device to perform holding, lifting, and lowering actions; the main control valve can achieve throttling control, which can improve the valve's micro-control performance and ensure the safety of the machine; the unloading valve can be piloted by the main control valve to reduce pressure loss; the logic valve can be piloted by the main control valve, ensuring reliable operation.

Description

Technical Field

[0001] This application relates to the field of hydraulic system technology, and in particular to a hydraulic lift valve with throttling control function and a hydraulic system. Background Technology

[0002] As a key actuator in hydraulic systems, the performance of the hydraulic lift valve directly affects the motion control accuracy of the load device. Existing hydraulic lift valves suffer from problems such as large pressure loss, poor pressure holding performance, easy leakage, poor control accuracy, and poor micro-motion performance due to their structure and hydraulic control layout.

[0003] Therefore, it is necessary to design a hydraulic lift valve with throttling control function to solve the above problems. Utility Model Content

[0004] In view of this, in order to overcome the defects of the prior art, this utility model provides a hydraulic lift valve and hydraulic system with throttling control function, which effectively solves the problems of large pressure loss, poor pressure holding performance, easy leakage, poor control accuracy and poor micro-motion performance of the existing hydraulic lift valve.

[0005] According to a first aspect of this utility model, a hydraulic lift valve with throttling control function is provided. The hydraulic lift valve includes a first connection port connected to an oil tank and a second connection port connected to a load device, as well as an unloading valve, a main control valve, and a logic valve connected to each other. The main control valve is connected to an external actuation mechanism to switch between a neutral position, a lifted position, and a lowered position. When the main control valve is in the neutral position, the first connection port is connected to the unloading valve through the main control valve, and the second connection port is locked. When the main control valve is in the lifted position, the first connection port is connected to the second connection port, and the unloading valve is closed. When the main control valve is in the lowered position, the first connection port is connected to the second connection port, and the unloading valve can be opened. The valve core of the main control valve has a fixed throttling orifice and a variable throttling groove.

[0006] Preferably, the hydraulic lift valve with throttling control function includes a third connection port connected to the oil tank. When the main control valve is in the neutral position, the spring side of the unloading valve is connected to the third connection port, and the first connection port is connected to the upper side of the unloading valve.

[0007] Preferably, when the main control valve is in the neutral position, the second connection port is connected to the spring side of the logic valve through the main control valve, and the logic valve is closed.

[0008] Preferably, when the main control valve is in the raised position, the first connection port is connected to the lower side of the logic valve, and the logic valve is opened.

[0009] Preferably, when the main control valve is in the lowered position, the connection between the second connection port and the main control valve is closed.

[0010] Preferably, when the main control valve is in the lowered position, the spring side of the unloading valve is connected to the third connection port through the main control valve.

[0011] Preferably, the hydraulic lift valve with throttling control function includes a fourth connection port connected to the oil tank. When the main control valve is in the lowered position, the first connection port is connected to the upper side of the unloading valve, so that the first connection port is connected to the fourth connection port.

[0012] Preferably, the hydraulic lift valve with throttling control function further includes a fifth connection port, wherein when the main control valve is in the lowered position, the spring side of the logic valve is connected to the fifth connection port through the main control valve.

[0013] Preferably, when the main control valve is in the lowered position, the second connection port is connected to the lower valve core of the logic valve to open the logic valve, and the second connection port is connected to the third connection port through the logic valve and the main control valve.

[0014] According to a second aspect of the present invention, a hydraulic system is provided, wherein the hydraulic system includes a hydraulically controlled lift valve with throttling control function as described above.

[0015] According to this utility model, a hydraulic lifting valve with throttling control function enables the load device to achieve holding, lifting, and lowering actions through the cooperation of an unloading valve, a main control valve, and a logic valve. The main control valve can achieve throttling control, the unloading valve can be piloted by the main control valve to reduce pressure loss and improve pressure holding performance, and the logic valve can be piloted by the main control valve to ensure reliable operation. The main control valve adopts a three-position six-way structure and is equipped with a fixed throttling orifice and a variable throttling groove at the valve port, which can improve the micro-control performance of the valve and ensure the safety of the machine.

[0016] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of a hydraulic lift valve with throttling control function in the neutral position according to an embodiment of the present invention is shown.

[0019] Figure 2 A schematic diagram of a hydraulic lift valve with throttling control function in the lift position according to an embodiment of the present invention is shown.

[0020] Figure 3 A schematic diagram of a hydraulic lift valve with throttling control function in a descending position according to an embodiment of the present invention is shown.

[0021] Reference numerals: 1-Unloading valve; 101-First spring side; 102-Upper side; 2-Main control valve; 201-Variable throttling groove; 202-Fixed throttling orifice; 3-Logic valve; 301-Second spring side; 302-Lower side; 4-First connection port; 5-Second connection port; 6-Third connection port; 7-Fourth connection port; 8-Fifth connection port. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0023] In the description of the embodiments of this application, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and 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. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0026] According to a first aspect of this utility model, a hydraulic lift valve with throttling control function is provided, such as... Figures 1 to 3 As shown, the hydraulic lift valve with throttling control function is used to control the operation of the load device. The hydraulic lift valve with throttling control function includes an unloading valve 1, a main control valve 2, and a logic valve 3.

[0027] In the following description, reference will be made to Figures 1 to 3 This section describes the detailed structure of the unloading valve 1, main control valve 2, and logic valve 3 of the hydraulic lift valve with throttling control function. Furthermore, the main control valve 2 can be understood as a composite valve composed of multiple different valve cores. The control method of this hydraulic lift valve with throttling control function can be understood as follows: the main control valve 2 controls the other functional valve cores through hydraulic control.

[0028] like Figures 1 to 3As shown, in this embodiment, the hydraulic lift valve with throttling control function includes a first connection port 4 connected to an oil tank (not shown), a second connection port 5 connected to a load device (not shown, but may be, for example, a load cylinder), and an unloading valve 1, a main control valve 2, and a logic valve 3 connected to each other. These three components are interconnected and achieve hydraulic oil flow and control by changing their different positions. Specifically, the main control valve 2 is connected to an external actuation mechanism (not shown, but may be, for example, a push rod, which the user can use to adjust the current position of the main control valve 2) so that the main control valve 2 switches between a neutral position, a lifted position, and a lowered position. As the main control valve 2 switches between these three positions, the hydraulic lift valve with throttling control function can simultaneously switch between the neutral, lifted, and lowered states, thereby driving the load device, such as a load cylinder, to perform different actions. Furthermore, when the main control valve 2 is in the neutral position, the first connection port 4 is connected to the unloading valve 1 through the main control valve 2, and the second connection port 5 is locked, so that the entire hydraulic lift valve is in the neutral state; when the main control valve 2 is in the lifting position, the first connection port 4 is connected to the second connection port 5, and the unloading valve 1 is closed, so that the entire hydraulic lift valve is in the lifting state; when the main control valve 2 is in the lowering position, the first connection port 4 is connected to the second connection port 5, and the unloading valve 1 can be opened, so that the load cylinder can be lowered, so that the entire hydraulic lift valve is in the lowering state.

[0029] Furthermore, such as Figure 2 and Figure 3 As shown, the valve core of the main control valve 2 has a fixed throttling orifice 202 and a variable throttling groove 201. When the main control valve 2 gradually moves from the neutral position to the raised position (e.g., Figure 2 As shown, the variable throttling groove 201 gradually opens from small to large, ensuring a smooth pressure rise at the second connection port 5 and reducing pressure shock. The fixed throttling orifice 202 ensures stable pressure in the spring chamber of the unloading valve 1, reducing pressure fluctuation. When the main control valve 2 gradually moves from the neutral position to the lowering position, the two variable throttling grooves 201 on the valve core of the main control valve 2 gradually open, ensuring that the inlet gradually opens from small to large, ensuring a smooth pressure rise at the second connection port 5 and reducing pressure shock. The return oil port gradually opens to prevent sudden excessive opening and excessively fast tool descent, which could lead to accidents.

[0030] This hydraulic lift valve with throttling control function enables the load device to perform holding, lifting, and lowering actions through the cooperation of unloading valve 1, main control valve 2, and logic valve 3. The main control valve 2 can achieve throttling control, and the unloading valve 1 can be piloted by the main control valve 2 to reduce pressure loss and improve pressure holding performance. The logic valve 3 is piloted by the main control valve 2 and is reliable in operation. The main control valve 2 adopts a three-position six-way structure and is equipped with a fixed throttling orifice 202 and a variable throttling groove 201 at the valve port, which can improve the micro-control performance of the valve and ensure the safety of the machine.

[0031] Preferably, such as Figure 1 As shown, in the embodiment, the hydraulic lift valve with throttling control function includes a third connection port 6 connected to the oil tank. When the main control valve 2 is in the neutral position, the spring side (i.e. the first spring side 101) of the unloading valve 1 is connected to the third connection port 6, and the first connection port 4 is connected to the upper side 102 of the unloading valve 1.

[0032] Preferably, such as Figure 1 As shown, in the embodiment, when the main control valve 2 is in the neutral position, the second connection port 5 is connected to the spring side (i.e., the second spring side 301) of the logic valve 3 through the main control valve 2, and the logic valve 3 is closed.

[0033] Preferably, such as Figure 2 As shown, in the embodiment, when the main control valve 2 is in the raised position, the first connection port 4 is connected to the lower side 302 of the logic valve 3, and the logic valve 3 is opened.

[0034] Preferably, such as Figure 2 As shown, in this embodiment, when the main control valve 2 is in the lowered position, the connection between the second connection port 5 and the main control valve 2 is closed.

[0035] Preferably, such as Figure 3 As shown, in the embodiment, when the main control valve 2 is in the lowered position, the first spring side 101 of the unloading valve 1 is connected to the third connection port 6 through the main control valve 2.

[0036] Preferably, such as Figure 3 As shown, in the embodiment, the hydraulic lift valve with throttling control function includes a fourth connection port 7 connected to the oil tank. When the main control valve 2 is in the lowered position, the first connection port 4 is connected to the upper side 102 of the unloading valve 1, so that the first connection port 4 is connected to the fourth connection port 7.

[0037] Preferably, such as Figure 3As shown, in this embodiment, the hydraulic lift valve with throttling control function also includes a fifth connection port 8. When the main control valve 2 is in the lowered position, the second spring side 301 of the logic valve 3 is connected to the fifth connection port 8 through the main control valve 2.

[0038] Preferably, such as Figure 3 As shown, in the embodiment, when the main control valve 2 is in the lowered position, the second connection port 5 is connected to the valve core of the lower side 302 of the logic valve 3 to open the logic valve 3. The second connection port 5 is connected to the third connection port 6 through the logic valve 3 and the main control valve 2.

[0039] The overall operation process of the hydraulic lift valve with throttling control function is as follows:

[0040] The oil tank is connected to the first connection port 4 via the pressure oil output by the hydraulic pump, the second connection port 5 is connected to the lifting cylinder (load device), and the fifth connection port 8, the fourth connection port 7 and the third connection port 6 are all connected to the oil tank.

[0041] like Figure 1 In the indicated state, the main control valve 2 is in the middle position, and the first connection port 4 is closed through the oil passage of the main control valve 2. Simultaneously, the control oil on the first spring side 101 of the unloading valve 1 is connected to the third connection port 6 through the middle position of the main control valve 2, preventing the control oil from building pressure. The pressure oil from the first connection port 4 acts on the upper side 102 of the unloading valve 1. According to the pressure balance formula, the pressure oil from the first connection port 4 only needs to overcome the spring resistance of the unloading valve 1 to open it, thus achieving unloading. Now, looking at the logic valve 3, the load pressure from the second connection port 5 reaches the second spring side 301 of the logic valve 3 through the oil passage in the middle position of the main control valve 2. According to the force analysis of the logic valve 3, since the area of ​​action of the upper pressure is greater than that of the lower pressure, the logic valve 3 is currently closed, the load cylinder of the second connection port 5 is locked, and the entire control valve is in a neutral position.

[0042] like Figure 2 In the indicated state, when the operating control mechanism pushes the valve core of the main control valve 2 to move to the left against the spring force on the left side of the main valve core, the main control valve 2 is in the right position. The first connection port 4 is connected to the lower side of the logic valve 3 through the oil circuit of the main control valve 2. At the same time, the control oil on the first spring side 101 of the unloading valve 1 is connected to the pressure oil through the right position of the main control valve 2. Under the action of the control oil, the unloading valve 1 is closed. The pressure oil from the second connection port 5 acts on the lower side of the logic valve 3. At this time, when the pressure at the first connection port 4 is the same as the pressure of the load cylinder at the second connection port 5, the logic valve 3 can be opened under the action of the pressure, connecting the first connection port 4 and the second connection port 5, realizing the lifting action of the load cylinder. The entire control valve is in the lifting state at this time.

[0043] like Figure 3 In the indicated state, after the control mechanism moves the valve core of the main control valve 2 to the right to reverse direction, the main control valve 2 is in the left position. The second connection port 5 is closed through the oil passage of the main control valve 2. At the same time, the control oil on the first spring side 101 of the unloading valve 1 is connected to the third connection port 6 through the left position of the main control valve 2, and the control oil cannot build up pressure. The pressure oil from the first connection port 4 acts on the upper side 102 of the unloading valve 1. According to the pressure balance formula, the pressure oil from the first connection port 4 only needs to overcome the spring resistance of the unloading valve 1 to open the unloading valve 1. The pressure oil from the first connection port 4 is connected to the fourth connection port 7 through the unloading valve 1 to achieve unloading. Now, looking at logic valve 3, the pressure oil in the upper spring chamber is connected to the fifth connection port 8 through the oil passage on the left side of the main control valve 2. The upper chamber of logic valve 3 is unloaded. At this time, the load pressure at the second connection port 5 acts on the lower valve core of logic valve 3, overcoming the spring force of logic valve 3 and opening logic valve 3. The second connection port 5 is connected to the oil port of the third connection port 6 through the internal oil passages of logic valve 3 and main control valve 2. The oil cylinder descends, and the entire control valve is now in the descending position.

[0044] This hydraulic lift valve with throttling control function enables the load device to perform holding, lifting, and lowering actions through the cooperation of an unloading valve, a main control valve, and a logic valve. The main control valve can achieve throttling control, the unloading valve can be piloted by the main control valve to reduce pressure loss and improve pressure holding performance, and the logic valve can be piloted by the main control valve for reliable operation. The main control valve adopts a three-position six-way structure and is equipped with a fixed throttling orifice and a variable throttling groove at the valve port, which can improve the valve's micro-control performance and ensure the safety of the equipment.

[0045] Furthermore, according to a second aspect of the present invention, a hydraulic system is provided, the hydraulic system including a hydraulically controlled lift valve with throttling control function as described above.

[0046] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A hydraulically controlled lift valve with throttling control function, characterized in that, The hydraulic lift valve with throttling control function includes a first connection port connected to the oil tank and a second connection port connected to the load device, as well as an unloading valve, a main control valve, and a logic valve connected to each other. The main control valve is connected to an external actuation mechanism to switch between a neutral position, a lift position, and a lower position. When the main control valve is in the neutral position, the first connection port is connected to the unloading valve through the main control valve, and the second connection port is locked. When the main control valve is in the lift position, the first connection port is connected to the second connection port, and the unloading valve is closed. When the main control valve is in the lower position, the first connection port is connected to the second connection port, and the unloading valve can be opened. The valve core of the main control valve has a fixed throttling orifice and a variable throttling groove.

2. The hydraulic lift valve with throttling control function according to claim 1, characterized in that, The hydraulic lift valve with throttling control function includes a third connection port connected to the oil tank. When the main control valve is in the neutral position, the spring side of the unloading valve is connected to the third connection port, and the first connection port is connected to the upper side of the unloading valve.

3. The hydraulic lift valve with throttling control function according to claim 2, characterized in that, When the main control valve is in the neutral position, the second connection port is connected to the spring side of the logic valve through the main control valve, and the logic valve is closed.

4. The hydraulic lift valve with throttling control function according to claim 1, characterized in that, When the main control valve is in the raised position, the first connection port is connected to the lower side of the logic valve, and the logic valve is opened.

5. The hydraulic lift valve with throttling control function according to claim 1, characterized in that, When the main control valve is in the lowered position, the connection between the second connection port and the main control valve is closed.

6. The hydraulic lift valve with throttling control function according to claim 2, characterized in that, When the main control valve is in the lowered position, the spring side of the unloading valve is connected to the third connection port through the main control valve.

7. The hydraulic lift valve with throttling control function according to claim 6, characterized in that, The hydraulic lift valve with throttling control function includes a fourth connection port connected to the oil tank. When the main control valve is in the lowered position, the first connection port is connected to the upper side of the unloading valve, so that the first connection port is connected to the fourth connection port.

8. The hydraulic lift valve with throttling control function according to claim 1, characterized in that, The hydraulic lift valve with throttling control function also includes a fifth connection port. When the main control valve is in the lowered position, the spring side of the logic valve is connected to the fifth connection port through the main control valve.

9. The hydraulic lift valve with throttling control function according to claim 3, characterized in that, When the main control valve is in the lowered position, the second connection port is connected to the lower valve core of the logic valve to open the logic valve. The second connection port is connected to the third connection port through the logic valve and the main control valve.

10. A hydraulic system, characterized in that, The hydraulic system includes a hydraulically controlled lift valve with throttling control function as described in any one of claims 1 to 9.

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