Proportional valve and hydraulic device having the same

Abstract

The application discloses a proportional valve and hydraulic equipment with the same, the proportional valve comprises a valve body and a valve core assembly, the valve body is provided with a valve core cavity, an oil inlet channel, a working port oil supply channel, a working port oil return channel and an oil tank oil return channel, and the two ends of the valve core cavity are respectively provided with a first valve core control cavity communicated with the working port oil supply channel and a second valve core control cavity communicated with the working port oil return channel, the valve core assembly comprises an electromagnet and a valve core arranged in the valve core cavity, the electromagnet can drive the valve core to move so that the oil inlet channel and the oil tank oil return channel are respectively communicated with the working port oil supply channel and the working port oil return channel, and the two ends of the valve core are both provided with a valve core push block. The proportional valve of the application uses hydraulic oil in the valve core control cavity to replace a traditional reset spring to realize valve core reset, avoids the problems that the valve core reset response is slow and the valve core cannot move to the position due to internal liquid vibration or aging of the spring, and improves the control precision of the proportional valve.

Description

Technical Field

[0001] This invention relates to the field of valve control technology, and more specifically, to a proportional valve and a hydraulic device having the same. Background Technology

[0002] Proportional valves are crucial components in hydraulic equipment, used for continuous, stepless regulation of hydraulic pressure. In related technologies, proportional valves utilize an electromagnet's internal push rod, driven by the electromagnetic force of a coil, to push a valve core in contact with it. The valve core opening is controlled by adjusting the current through the push rod's displacement. Spring seats and springs on both sides of the valve core ensure its return to its original position. When the electromagnets are energized, the electromagnetic force overcomes the spring force, pushing the valve core forward. When the electromagnets are de-energized, the valve core returns to its neutral position under the spring force. However, when fluid flows through the valve, spring vibration reduces its lifespan, and spring fatigue leads to changes in stiffness, both of which negatively impact the proportional valve's control accuracy. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to propose a proportional valve that addresses the defects and deficiencies of the prior art. This proportional valve can use the hydraulic oil in the valve core control chamber to replace the traditional return spring to achieve valve core reset, avoiding the problems of slow valve core reset response and incomplete movement caused by internal fluid vibration or aging of the spring, thereby improving the control accuracy of the proportional valve.

[0004] Embodiments of the present invention also propose a hydraulic device.

[0005] The proportional valve of this invention includes: a valve body having a valve core cavity, an oil inlet channel, a working port oil supply channel, a working port oil return channel, and an oil tank oil return channel; a first valve core control cavity and a second valve core control cavity are respectively provided at both ends of the valve core cavity; the first valve core control cavity is connected to the working port oil supply channel, and the second valve core control cavity is connected to the working port oil return channel; and a valve core assembly including an electromagnet and a valve core disposed in the valve core cavity; the electromagnet can drive the valve core to move so that the oil inlet channel and the oil tank oil return channel are respectively connected to the working port oil supply channel and the working port oil return channel; and valve core push blocks are provided at both ends of the valve core.

[0006] In this embodiment of the proportional valve, the valve core cavity has a first valve core control cavity and a second valve core control cavity at both ends. The first valve core control cavity is connected to the working port oil supply channel, and the second valve core control cavity is connected to the working port oil return channel. An electromagnet can drive the valve core to move so that the oil inlet channel and the oil tank return channel are respectively connected to the working port oil supply channel and the working port oil return channel. Both ends of the valve core are provided with valve core push blocks. Thus, when the electromagnet drives the valve core to open, part of the hydraulic oil flows to the working port oil supply channel, and the other part flows into the first valve core control cavity. When the electromagnet is de-energized, the pressure applied by the hydraulic oil in the first valve core control cavity can drive the valve core to reset until the valve core closes the working port oil supply channel, the hydraulic pressure disappears, and the valve core returns to the neutral position. Therefore, this application can use the hydraulic oil in the valve core control cavity to replace the traditional reset spring to realize the valve core reset, avoiding the problem of slow valve core reset response and incomplete movement caused by internal fluid vibration or aging of the spring, thus improving the control accuracy of the proportional valve.

[0007] In some embodiments, the peripheral wall of the valve core cavity is provided with an oil supply port, an oil return port, and an oil inlet located between the two. The oil inlet is connected to the oil inlet channel, the oil supply port is connected to the working port oil supply channel, and the oil return port is connected to the working port oil return channel. The valve core includes a valve stem and a first valve plug and a second valve plug disposed on the valve stem and spaced apart along its length. Both the first valve plug and the second valve plug are in sealing contact with the inner wall of the valve core cavity. When the valve core is in the neutral position, the first valve plug closes the oil supply port, and the second valve plug blocks the oil return port.

[0008] In some embodiments, the oil tank return channel includes a first channel and a second channel, and the peripheral wall of the valve core cavity is further provided with a first return port and a second return port. The first return port is connected to the first channel and is located on the side of the oil supply port away from the oil inlet port, and the second return port is connected to the second channel and is located on the side of the return port away from the oil inlet port.

[0009] In some embodiments, the oil tank return channel further includes a main channel that is connected to both the first channel and the second channel, and the main channel is connected to the oil tank.

[0010] In some embodiments, the valve stem includes a body and a valve head, the body being disposed within the valve core cavity and the valve core pusher being located at the end of the body, the valve head being located on the side of the valve core pusher opposite to the body, and at least a portion of the valve head extending into the valve core control cavity.

[0011] In some embodiments, the proportional valve further includes a sealing plug located within the valve core control cavity and surrounding the outer periphery of the valve head, and the sealing plug is in sealing contact with the bottom wall of the valve core control cavity. The inner diameter of the sealing plug is larger than the diameter of the valve head but smaller than the cross-sectional diameter of the valve core cavity.

[0012] In some embodiments, the outer diameter of the sealing plug is smaller than the cross-sectional diameter of the valve core control cavity.

[0013] In some embodiments, the proportional valve further includes a limiting member located on the side of the sealing plug away from the valve core cavity and connected to the valve body, and the limiting member can abut against the side of the sealing plug away from the valve core cavity.

[0014] In some embodiments, the limiting member is a fixed plug, which is spaced around the outer periphery of the valve head and fixedly connected to the inner peripheral wall of the valve core control cavity.

[0015] The hydraulic device of this invention includes the proportional valve described in the above embodiments.

[0016] The hydraulic equipment of this invention employs the aforementioned proportional valve. The valve core cavity has a first valve core control chamber and a second valve core control chamber at both ends. The first valve core control chamber is connected to the working port oil supply channel, and the second valve core control chamber is connected to the working port return channel. An electromagnet can drive the valve core to move so that the oil inlet channel and the oil tank return channel are respectively connected to the working port oil supply channel and the working port return channel. Both ends of the valve core are equipped with valve core push blocks. Thus, when the electromagnet drives the valve core to open, part of the hydraulic oil flows to the working port oil supply channel, and the other part flows into the first valve core control chamber. When the electromagnet is de-energized, the pressure applied by the hydraulic oil in the first valve core control chamber can drive the valve core to reset until the valve core closes the working port oil supply channel. The hydraulic pressure then disappears, and the valve core returns to its neutral position. Therefore, this application can utilize the hydraulic oil in the valve core control chamber to replace the traditional return spring to achieve valve core reset, avoiding the problems of slow valve core reset response and incomplete movement caused by internal fluid vibration or aging of the spring. The proportional valve has high control accuracy, and the hydraulic equipment has good performance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the proportional valve according to an embodiment of the present invention.

[0018] Figure 2 This is a partial enlarged view of the proportional valve according to an embodiment of the present invention.

[0019] Figure label:

[0020] Valve body 1, valve core cavity 2, oil inlet 3, oil supply port 4, oil return port 5, first oil return interface 61, second oil return interface 62, first valve core control cavity 7, second valve core control cavity 8, valve core 9, valve stem 91, first valve plug 92, second valve plug 93, valve core push block 94, sealing plug 10, limit component 11. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] like Figure 1 and Figure 2 As shown, the proportional valve in this embodiment of the invention includes a valve body 1 and a valve core assembly.

[0023] Specifically, such as Figure 1 As shown, the valve body 1 has a valve core cavity 2, an oil inlet channel, a working port oil supply channel, a working port oil return channel, and an oil tank oil return channel. The valve core cavity 2 has a first valve core control cavity 7 and a second valve core control cavity 8 at its two ends. The first valve core control cavity 7 is connected to the working port oil supply channel, and the second valve core control cavity 8 is connected to the working port oil return channel. The valve core assembly includes an electromagnet and a valve core 9 disposed in the valve core cavity 2. The electromagnet can drive the valve core 9 to move so that the oil inlet channel and the oil tank oil return channel are connected to the working port oil supply channel and the working port oil return channel, respectively. The valve core 9 has valve core push blocks 94 at both ends.

[0024] It should be noted that, in this application, the functions of the oil supply channel and the oil return channel at the working port are interchangeable when the valve core moves in a turning direction. For example, if... Figure 1 As shown, taking the position of port A as the working port oil supply channel as an example, and the position of port B as the working port oil return channel, the electromagnet is energized to control the valve core 9 to move to the left, the working port oil supply channel and the working port oil return channel are opened, and the working port oil supply channel is connected to the oil inlet 3 through the valve core cavity 2, and the working port oil return channel is connected to the oil tank oil return channel through the valve core cavity 2. At this time, part of the hydraulic oil flows to the working surface through the working port oil supply channel, and after the work is completed, it flows back to the oil tank through the working port oil supply channel and the oil tank oil return channel. The other part of the hydraulic oil flows into the first valve core control cavity 7 connected to the working port oil supply channel. The hydraulic oil in the first valve core control cavity 7 will apply a pressure to the valve core push block 94 to the right. When the driving force provided by the electromagnet is consistent with the pressure provided by the hydraulic oil in the first valve core control cavity 7, the valve core 9 no longer moves, and at this time the valve core 9 remains at a fixed opening.

[0025] Furthermore, when the working face no longer needs oil, the electromagnet can be de-energized, and the hydraulic oil in the first valve core control chamber 7 can push the valve core 9 to move to the right to reset until the valve core 9 moves to the middle position, and the oil supply channel and oil return channel of the working port are closed, and the equipment is in a stopped or standby state.

[0026] It is understandable that when the position shown by port A is the working port return oil channel, the position of port B is the working port supply oil channel. The electromagnet can control the valve core 9 to move in the opposite direction. Its opening and resetting principle is the same as above, and will not be repeated here.

[0027] In this embodiment of the proportional valve, the valve core cavity 2 has a first valve core control cavity 7 and a second valve core control cavity 8 at both ends. The first valve core control cavity 7 is connected to the working port oil supply channel, and the second valve core control cavity 8 is connected to the working port oil return channel. An electromagnet can drive the valve core 9 to move so that the oil inlet channel and the oil tank return channel are connected to the working port oil supply channel and the working port oil return channel, respectively. Both ends of the valve core 9 are provided with valve core push blocks 94. Thus, when the electromagnet drives the valve core 9 to open, part of the hydraulic oil flows to the working port oil supply channel, and the other part flows into the first valve core control cavity 7. When the electromagnet is de-energized, the pressure applied by the hydraulic oil in the first valve core control cavity 7 can drive the valve core 9 to reset until the valve core 9 closes the working port oil supply channel, the hydraulic pressure disappears, and the valve core 9 returns to the neutral position. Thus, this application can use the hydraulic oil in the valve core 9 control cavity to replace the traditional reset spring to reset the valve core 9, avoiding the problem of slow reset response and incomplete movement of the valve core 9 caused by internal fluid vibration or aging of the spring, thereby improving the control accuracy of the proportional valve.

[0028] Furthermore, such as Figure 1 As shown, the peripheral wall of the valve core cavity 2 is provided with an oil supply port 4, an oil return port 5, and an oil inlet port 3 located between the two. The oil inlet port 3 is connected to the oil inlet channel, the oil supply port 4 is connected to the oil supply channel of the working port, and the oil return port 5 is connected to the oil return channel of the working port. The valve core 9 includes a valve stem 91 and a first valve plug 92 and a second valve plug 93 arranged on the valve stem 91 and spaced apart along its length. The first valve plug 92 and the second valve plug 93 are both in sealing contact with the inner wall of the valve core cavity 2. When the valve core 9 is in the neutral position, the first valve plug 92 closes the oil supply port 4, and the second valve plug 93 closes the oil return port 5.

[0029] Therefore, by using the valve plug on the valve stem 91 to open and close the communication port, it is only necessary to ensure the sealing fit between the valve plug and the valve core cavity 2. The valve stem 91 does not contact the inner wall of the valve core cavity 2, thus avoiding the problem of high processing difficulty caused by multi-stage coaxiality due to the machining of the slide valve hole or the fit of the valve sleeve in the prior art.

[0030] Preferably, the first valve plug 92 and the second valve plug 93 have an annular stepped structure.

[0031] Furthermore, such as Figure 1 As shown, the oil tank return channel includes a first channel and a second channel. The peripheral wall of the valve core cavity 2 is also provided with a first return port 61 and a second return port 62. The first return port 61 is connected to the first channel and located on the side of the oil supply port 4 opposite to the oil inlet port 3. The second return port 62 is connected to the second channel and located on the side of the return port 5 opposite to the oil inlet port 3. For ease of understanding, as... Figure 1 As shown, when the valve core 9 moves to the left, the first valve plug 92 moves to the left to open port A. At the same time, the first valve plug 92 seals between the first return oil port 61 (left T port) and port A, and the hydraulic oil is supplied towards port A. The second valve plug 93 moves to the left to open port B. At the same time, the second valve plug 93 seals between port B and inlet port 3, and the return oil from the working surface can flow into the second return oil port 62 (right T port) through port B.

[0032] Preferably, the oil return channel of the oil tank also includes a main channel that is connected to both the first channel and the second channel, and the main channel is connected to the oil tank. Thus, the hydraulic oil in the first channel and the second channel can collect in the main channel and eventually flow into the oil tank, simplifying the pipeline layout and the number of interface pipes.

[0033] Furthermore, such as Figure 1 and Figure 2 As shown, the valve stem 91 includes a body and a valve head. The body is located within the valve core cavity 2, and the valve core push block 94 is located at the end of the body. The valve head is located on the side of the valve core push block 94 away from the body, and at least a portion of the valve head extends into the valve core 9 control cavity. The proportional valve also includes a sealing plug 10, which is located within the valve core 9 control cavity and surrounds the outer periphery of the valve head. The sealing plug 10 is in sealing contact with the bottom wall of the valve core 9 control cavity. The inner diameter of the sealing plug 10 is larger than the diameter of the valve head but smaller than the cross-sectional diameter of the valve core cavity 2. Therefore, when the hydraulic oil in the valve core 9 control cavity pushes the valve core 9 to reset, it needs to flow in from the gap between the sealing plug 10 and the valve head and apply pressure towards the surface of the valve core push block 94. Because the gap between the sealing plug 10 and the valve head is small, the contact area between the hydraulic oil and the valve core push block 94 can be reduced, thereby effectively reducing the thrust requirement of the electromagnet and allowing the use of a smaller electromagnet, reducing the space occupied in assembly.

[0034] Preferably, the outer diameter of the sealing plug 10 is smaller than the cross-sectional diameter of the control cavity of the valve core 9. Therefore, the control cavity of the valve core 9 can reserve some space for the sealing plug 10 in the radial direction of the valve core 9, allowing the sealing plug 10 to adaptively float up and down, reducing the requirement for coaxiality, improving manufacturability, and reducing processing costs.

[0035] Preferably, such as Figure 2As shown, the proportional valve also includes a limiting member 11. The limiting member 11 is located on the side of the sealing plug 10 away from the valve core cavity 2 and is connected to the valve body 1. The limiting member 11 can stop the sealing plug 10 from the side away from the valve core cavity 2. It should be noted that in order to allow the sealing plug 10 to float up and down, the sealing plug 10 and the bottom wall of the valve core 9 control cavity are only in sealing contact through a sealing ring and there is no fixed connection relationship. Therefore, by setting the limiting member 11 to stop the sealing plug 10 from moving axially, the limiting member 11 can prevent the sealing plug 10 from tilting or slipping axially.

[0036] Preferably, the limiting member 11 is a fixed plug, which is spaced around the outer periphery of the valve head and fixedly connected to the inner peripheral wall of the control cavity of the valve core 9.

[0037] The hydraulic device of this invention includes the proportional valve described in the above embodiments.

[0038] The hydraulic equipment of this invention employs the aforementioned proportional valve. The valve core cavity 2 has a first valve core control cavity 7 and a second valve core control cavity 8 at both ends. The first valve core control cavity 7 is connected to the working port oil supply channel, and the second valve core control cavity 8 is connected to the working port oil return channel. An electromagnet can drive the valve core 9 to move so that the oil inlet channel and the oil tank return channel are respectively connected to the working port oil supply channel and the working port oil return channel. Furthermore, valve core push blocks 94 are provided at both ends of the valve core 9. Therefore, when the electromagnet drives the valve core 9 to open, a portion of the hydraulic oil flows to the working port oil supply channel. One part flows into the oil passage, and the other part flows into the first valve core control chamber 7. When the electromagnet is de-energized, the pressure applied by the hydraulic oil in the first valve core control chamber 7 can drive the valve core 9 to reset until the valve core 9 closes the working port oil supply passage. Then the hydraulic pressure disappears and the valve core 9 returns to the neutral position. Thus, this application can use the hydraulic oil in the valve core 9 control chamber to replace the traditional reset spring to realize the reset of the valve core 9, avoiding the problem of slow reset response and incomplete movement of the valve core 9 caused by internal fluid vibration or aging of the spring. The proportional valve has high control accuracy and the hydraulic equipment has good performance.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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 invention.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0043] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0044] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A proportional valve, characterized in that, include: The valve body has a valve core cavity, an oil inlet channel, a working port oil supply channel, a working port oil return channel, and an oil tank oil return channel. The valve core cavity has a first valve core control cavity and a second valve core control cavity at its two ends. The first valve core control cavity is connected to the working port oil supply channel, and the second valve core control cavity is connected to the working port oil return channel. A valve core assembly includes an electromagnet and a valve core disposed within the valve core cavity. The electromagnet can drive the valve core to move so that the oil inlet channel and the oil tank return channel are respectively connected to the working port oil supply channel and the working port oil return channel. Both ends of the valve core are provided with valve core push blocks. The valve core includes a valve stem, which includes a body and a valve head. The body is disposed within the valve core cavity, and the valve core push block is located at the end of the body. The valve head is located on the side of the valve core push block opposite to the body, and at least a portion of the valve head extends into the valve core control cavity. A sealing plug is located inside the valve core control cavity and surrounds the outer periphery of the valve head. The sealing plug is in sealing contact with the bottom wall of the valve core control cavity. The inner diameter of the sealing plug is larger than the diameter of the valve head but smaller than the cross-sectional diameter of the valve core cavity. When the valve core controls the hydraulic oil in the valve core cavity to push the valve core to reset, it needs to flow in from the gap between the sealing plug and the valve head and apply pressure toward the surface of the valve core push block.

2. The proportional valve according to claim 1, characterized in that, The valve core cavity has an oil supply port, an oil return port, and an oil inlet located between the two on its peripheral wall. The oil inlet is connected to the oil inlet channel, the oil supply port is connected to the working port oil supply channel, and the oil return port is connected to the working port oil return channel. The valve core includes a first valve plug and a second valve plug disposed on the valve stem and spaced apart along its length. Both the first valve plug and the second valve plug are in sealing contact with the inner wall of the valve core cavity. When the valve core is in the neutral position, the first valve plug closes the oil supply port, and the second valve plug blocks the oil return port.

3. The proportional valve according to claim 2, characterized in that, The oil tank return channel includes a first channel and a second channel. The peripheral wall of the valve core cavity is also provided with a first return port and a second return port. The first return port is connected to the first channel and is located on the side of the oil supply port away from the oil inlet. The second return port is connected to the second channel and is located on the side of the return port away from the oil inlet.

4. The proportional valve according to claim 3, characterized in that, The oil return channel of the oil tank also includes a main channel that is connected to both the first channel and the second channel, and the main channel is connected to the oil tank.

5. The proportional valve according to claim 1, characterized in that, The outer diameter of the sealing plug is smaller than the cross-sectional diameter of the valve core control cavity.

6. The proportional valve according to claim 1, characterized in that, It also includes a limiting member, which is located on the side of the sealing plug away from the valve core cavity and connected to the valve body, and the limiting member can abut against the side of the sealing plug away from the valve core cavity.

7. The proportional valve according to claim 6, characterized in that, The limiting component is a fixed plug, which is spaced around the outer periphery of the valve head and fixedly connected to the inner peripheral wall of the valve core control cavity.

8. A hydraulic device, characterized in that, Includes a proportional valve according to any one of claims 1-7.

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