Pilot control valve, hydraulic control system and working machine

Abstract

This application discloses a pilot control valve, a hydraulic control system, and a working machine. The valve body assembly has a first valve chamber inside, one end of which is connected to a control valve. A control port is provided at the end of the valve body assembly facing the control valve. A floating valve core is located within the first valve chamber and includes a floating core body. One end of the floating core body is movably inserted into the assembly, and the other end can movably pass through the control port. A pressure-dividing assembly includes an elastic element and a first damper. The elastic element is elastically connected between the inner wall of the assembly and the floating core body, and the first damper is inserted into an inner hole. The end of the floating core body facing away from the elastic element is used to abut against a control piston. Hydraulic oil flowing from the control port is used to drive the control piston to move. The elastic element drives the floating core body to move axially and changes the distance between the floating core body and the valve body assembly to adjust the hydraulic oil output flow rate at the control port. The pilot control valve of this application enables the actuator to perform smooth movement while improving response speed.

Description

Technical Field

[0001] This application belongs to the field of operating machinery technology, specifically relating to a pilot control valve, a hydraulic control system, and operating machinery. Background Technology

[0002] With the rapid development of operating machinery, users have increasingly higher requirements for the timeliness, stability, and controllability of the actuators when operating cranes, especially during crane hoisting and "pile-setting" operations, where extremely high demands are placed on the micro-motion and stability performance of the hoisting and luffing mechanisms. Existing load-holding valves, to ensure smooth start-up, generally incorporate a damping network in the pilot control mechanism, largely mitigating the vibration problem. However, the damping network of the pilot mechanism is often fixed. When the control pressure is input at the inlet, after passing through the fixed damper, the pressure build-up speed at the output port is difficult to guarantee, meaning the actuator's response speed is relatively slow. If the damping is removed or increased, vibration of the actuator is likely to occur. In other words, the rapid response and smooth operation of the actuator are contradictory and cannot be simultaneously satisfied, directly affecting the user's operating experience. Summary of the Invention

[0003] The purpose of this application is to provide a pilot control valve, a hydraulic control system, and a working machine that enables the actuator to perform smooth movements while improving response speed.

[0004] To achieve the above objectives, this application provides a pilot control valve, comprising: A valve body assembly has a first valve chamber inside, one end of the valve body assembly is used to connect to a control valve, and a control port is opened at the end of the valve body assembly facing the control valve. A floating valve core is located in the first valve chamber. The floating valve core includes a floating core body. One end of the floating core body is movably inserted into the valve body assembly, and the other end can movably pass through the control port. The pressure dividing assembly includes an elastic element and a first damper. The elastic element is elastically connected between the inner wall of the valve body assembly and the floating core. The first damper is inserted into the floating core. The end of the floating core facing away from the elastic element abuts against the control piston of the control valve. Hydraulic oil flowing from the control port is used to drive the control piston to move, and the elastic element is used to drive the floating core to move axially and change the oil passage area between the floating core and the valve body assembly, so as to adjust the hydraulic oil output flow rate of the control port.

[0005] In some embodiments, the valve body assembly includes a valve body and a valve sleeve located in a first valve cavity. One end of the floating core is movably inserted into the valve sleeve. The valve sleeve has a second valve cavity, which includes a first cavity, a second cavity, and a third cavity connected sequentially along the axial direction. The elastic element is located in the second cavity and its two ends are respectively connected to the end face of the second cavity and the floating core. The floating core is movably located in the third cavity.

[0006] In some embodiments, the first cavity is provided with a second damping, the second damping including a first end cap and a damping body connected to the first end cap, the first end cap being located at the end of the valve sleeve away from the floating core and having an outer diameter larger than the inner diameter of the first cavity, and the damping body being located within the first cavity.

[0007] In some embodiments, the first valve cavity includes a fourth cavity, a fifth cavity, and a sixth cavity that are sequentially connected along the axial direction and whose inner diameters decrease sequentially. The valve sleeve is located in the fourth cavity. The floating core includes a large-diameter portion, a valve seat, and a small-diameter portion that are sequentially connected along the axial direction. The valve seat includes a frustum portion and an annular portion. The outer diameter of the frustum portion decreases from the direction away from the large-diameter portion. The outer diameter of the annular portion is equal to the outer diameter of the end of the frustum portion and smaller than the outer diameter of the small-diameter portion. The large-diameter portion is movably located in the fifth cavity. The maximum outer diameter of the frustum portion is smaller than the inner diameter of the fifth cavity and larger than the inner diameter of the sixth cavity. The small-diameter portion is movably located in the sixth cavity.

[0008] In some embodiments, an oil passage is provided on the outer periphery of the frustum portion, and the oil passage communicates with the third cavity.

[0009] In some embodiments, the pilot control valve further includes an oil inlet connector inserted into the first valve chamber. The oil inlet connector and the valve sleeve are arranged at a distance from one end of the floating core. The oil inlet connector forms an oil inlet channel communicating with the first valve chamber. The oil inlet connector is provided with a third damping.

[0010] In some embodiments, the valve body is further provided with a pressure-dividing oil passage that is perpendicular to and connected to the central axis of the first valve cavity. The pressure-dividing oil passage is connected to an external hydraulic oil tank through a pipeline. The pressure-dividing oil passage is provided with a fourth damper and a blocking ball. The pressure-dividing oil passage is used to divert the hydraulic oil in the first valve cavity, and the blocking ball is used to connect or block the pressure-dividing oil passage and the oil passage of the first valve cavity.

[0011] In some embodiments, the pressure-distributing oil circuit includes a first pressure-distributing chamber, a second pressure-distributing chamber, and a third pressure-distributing chamber that are connected in sequence and have progressively larger inner diameters. The third pressure-distributing chamber is connected to the first valve chamber, and the barrier ball is located in the second pressure-distributing chamber and has an outer diameter larger than the inner diameter of the first pressure-distributing chamber. The fourth damper has a pressure-dividing hole along the axial direction and includes a first damping part, a second damping part, and a third damping part connected in sequence. The third damping part has a notch communicating with the pressure-dividing hole. The first damping part is located in the first pressure-dividing cavity and its outer diameter is larger than the inner diameter of the second pressure-dividing cavity. The second damping part and the third damping part are both located in the second pressure-dividing cavity. The hydraulic oil flowing in from the third pressure-dividing cavity is used to apply a linear driving force to the blocking ball so that the blocking ball moves and abuts against the end face of the notch.

[0012] In some embodiments, the valve body is further provided with a bypass channel communicating with the third pressure chamber. The bypass channel extends from the third pressure chamber to the side of the valve body facing the control valve and has a bypass port.

[0013] A second aspect of this application provides a hydraulic control system, including a control valve and a pilot control valve as described above.

[0014] A third aspect of this application provides a working machine, including the hydraulic control system described above.

[0015] Through the above technical solution, the valve body assembly of the pilot control valve of this application has a first valve chamber inside. One end of the valve body assembly is used to connect with the control valve, which is used to supply oil to the actuator. The valve body assembly has a control port at the end facing the control valve. The floating valve core is located in the first valve chamber. The floating valve core includes a floating core body. One end of the floating core body is movably inserted into the valve body assembly, and the other end can move through the control port. The pressure dividing assembly includes an elastic element and a first damper. The elastic element is elastically connected between the inner wall of the valve body assembly and the floating core body. The first damper is inserted into the floating core body. The end of the floating core body away from the elastic element abuts against the control valve. When hydraulic oil enters the first valve chamber, it is filtered by the first damper and flows out from the control port. The hydraulic oil flowing out from the control port drives the control piston to move. Meanwhile, the floating core moves axially through the control port under the elastic drive of the elastic element, thereby changing the oil passage area between the floating core and the valve body assembly. In this way, the hydraulic oil output flow rate of the control port is automatically adjusted, which can achieve smooth movement of the actuator while improving the response speed, that is, to achieve rapid pressure build-up at the control port.

[0016] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without any inventive effort. In the drawings: Figure 1 This is a schematic diagram of the hydraulic principle of the pilot control valve of this application; Figure 2 This is a schematic diagram of the floating core of the pilot control valve in the first position of this application; Figure 3 This is a schematic diagram of the floating core of the pilot control valve of this application when it is in the middle position; Figure 4 This is a schematic diagram of the floating core of the pilot control valve in the second position of this application; Figure 5 This is a schematic diagram of the valve sleeve in the pilot control valve of this application; Figure 6 This is a schematic diagram of the floating core in the pilot control valve of this application; Figure 7 This is a schematic diagram of the fourth damper in the pilot control valve of this application; Figure 8 This is a schematic diagram of the valve body in the pilot control valve of this application.

[0018] Explanation of reference numerals in the attached figures Detailed Implementation

[0019] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0020] The pilot control valve, hydraulic control system, and working machinery according to this application are described below with reference to the accompanying drawings.

[0021] like Figure 1 As shown, this application provides a pilot control valve, including a valve body assembly, a floating valve core, and a pressure dividing assembly; the valve body assembly has a first valve chamber 10 inside, one end of the valve body assembly is used to connect to a control valve 40, the control valve 40 is used to supply oil to an actuator, and a control port Y is opened at the end of the valve body assembly facing the control valve 40; the floating valve core is located in the first valve chamber 10, and the floating valve core includes a floating core 21, one end of the floating core 21 is movably inserted into the assembly, and the other end can movably pass through the control port Y, that is, the other end of the floating core 21 can pass through the control port Y and abut against the control piston (e.g. Figure 1 As shown), of course, the other end of the floating core 21 may not pass through the control port Y but can still abut against the control piston. Both of these situations are within the protection scope of the present invention. The pressure dividing assembly includes an elastic element 31 and a first damper 32. The elastic element 31 is elastically connected between the inner wall of the valve body assembly and the floating core 21. The first damper 32 is inserted into the inner hole 22. The end of the floating core 21 facing away from the elastic element 31 abuts against the control piston of the control valve 40. The hydraulic oil flowing out from the control port Y is used to drive the control piston to move. The elastic element 31 is used to drive the floating core 21 to move between the first position and the second position to change the oil passage area between the floating core 21 and the valve body assembly, thereby adjusting the hydraulic oil output flow rate of the control port Y.

[0022] The valve body assembly includes a valve body 100 and a valve sleeve 20 located in the first valve chamber 10. One end of a floating core 21 is movably inserted into the valve sleeve 20. An elastic element 31 is elastically connected between the inner wall of the valve sleeve 20 and the floating core 21. When the elastic element 31 drives the floating core 21 to move axially, the hydraulic oil output flow rate of the control port Y can be adjusted by changing the oil flow area between the floating core 21 and the valve body 100, or by changing the oil flow area between the floating core 21 and the valve sleeve 20. The floating core 21 of this application can move with the control piston of the control valve 40, and thus adjust the hydraulic oil output flow rate of the control port Y accordingly. That is, the position change of the floating core 21 can automatically adjust the oil flow area between the floating core 21 and the valve body 100 or the valve sleeve 20, thereby enabling the actuator to perform smooth movement while improving the response speed, that is, to achieve rapid pressure build-up at the control port Y.

[0023] For ease of explanation, the following example illustrates how the positional change of the floating core 21 can automatically adjust the oil passage area between the floating core 21 and the valve body 100. In this embodiment, when there is no control oil input at the oil inlet or when control oil output has just begun, the floating core 21 is in the first position of L1 (e.g., Figure 2 As shown), the elastic element 31 has elastic potential energy due to compression deformation. At this time, the oil passage area formed by the cooperation between the end of the floating core 21 away from the elastic element 31 and the first valve chamber 10 of the valve body 100 is the largest, which makes the control port Y quickly build up pressure and ensure the rapid response of the actuator. As the control oil in the oil inlet continues to output, it pushes the control piston of the control valve 40 to move to the right, and the elastic element 31 drives the floating core 21 to move to the right accordingly. When the floating core 21 moves to the middle position of L2 ( Figure 3As shown, the inclined surface of the floating core 21 contacts the sharp corner of the valve body 100. At this time, the input oil passage area of ​​the control port Y becomes smaller, and the floating core 21 is in the L1-L2 stage, which is the rapid opening stage of the actuator. As the control oil in the oil inlet continues to output, it pushes the control piston to continue moving to the right. At this time, when the floating core 21 is disengaged from the control piston and is in the second position of L3 (as shown), the control piston is in the second position. Figure 4 As shown in the diagram, at this time, the elastic element 31 does not have elastic deformation, so the floating core 21 will not continue to move to the right, and the effective oil passage area of ​​the control port Y will not increase, remaining the same as the oil passage area in state L2. This ensures the stability of the output pressure of the control port Y, thus ensuring the smooth movement of the actuator. When the floating core 21 is in the L2-L3 stage, it is the smooth movement stage of the actuator. When the pressure at the oil inlet decreases or the actuator needs to be stopped, the control pressure oil at the control port Y pushes the floating core 21 to the left (L3-L1), causing the pressure oil at the control port Y to be quickly depressurized, thereby achieving a rapid stop or reset of the actuator.

[0024] Furthermore, since the floating core 21 of this application is provided with a first damper 32, when the pressure at the oil inlet fluctuates, part of the pressure generated by the fluctuation can be filtered by the first damper 32, thereby achieving a rapid response and smooth operation of the actuator.

[0025] In some embodiments, the valve sleeve 20 has a second valve chamber, which includes a first cavity 201, a second cavity 202, and a third cavity 203 that are sequentially connected axially and have progressively increasing inner diameters. An elastic element 31 is located within the second cavity 202 and its two ends are respectively connected to the end face of the second cavity 202 and the floating core 21. The floating core 21 is movably located within the third cavity 203, and a channel gap for hydraulic oil flow exists between the floating core 21 and the inner peripheral wall of the third cavity 203. In this embodiment, in the first position, the elastic element 31 is in a compressed state and exerts an elastic force on the floating core 21 in the direction of the control piston. When hydraulic oil enters from the inlet port X, the hydraulic oil is filtered by the first damper 32 and flows out along the inner hole 22 of the floating core 21. A portion of the oil flows out through the channel gap between the floating core 21 and the inner peripheral wall of the third cavity 203 and applies an axial pushing force to the control piston. Thus, under the elastic action of the elastic element 31, the floating core 21 moves to the right along with the control piston to the second position. When the floating core 21 moves between the first position and the second position, the hydraulic oil flow rate at the control port Y changes accordingly, thereby enabling the balance valve to respond quickly and operate smoothly.

[0026] In some embodiments, the first cavity 201 is provided with a second damper 33, which includes a first end cap and a damping body connected to the first end cap. The first end cap is located at the end of the valve sleeve 20 opposite to the floating core 21 and its outer diameter is larger than the inner diameter of the first cavity 201. The damping body is located inside the first cavity 201. The second damper 33 can filter the hydraulic oil, thereby reducing hydraulic oil fluctuations entering from the first cavity 201.

[0027] like Figure 8 As shown, the first valve chamber 10 includes a fourth chamber 101, a fifth chamber 102, and a sixth chamber 103 that are sequentially connected along the axial direction and whose inner diameters decrease sequentially. The valve sleeve 20 is located in the fourth chamber 101. The floating core 21 includes a large-diameter portion 211, a valve seat 212, and a small-diameter portion 213 that are sequentially connected along the axial direction. The valve seat 212 includes a frustum portion 2121 and an annular portion 2122. The outer diameter of the frustum portion 2121 decreases from the direction away from the large-diameter portion 211. As the floating core 21 moves to the right, the frustum portion... The distance between 2121 and valve sleeve 20 gradually decreases until it abuts against the inner wall of valve body 100, thereby changing the oil passage area between frustum portion 2121 and valve body 100; the outer diameter of annular portion 2122 is equal to the end outer diameter of frustum portion 2121 and smaller than the outer diameter of small diameter portion 213; large diameter portion 211 is movably located in fifth cavity 102; the maximum outer diameter of frustum portion 2121 is smaller than the inner diameter of fifth cavity 102 and larger than the inner diameter of sixth cavity 103; small diameter portion 213 is movably located in sixth cavity 103.

[0028] In this embodiment, the valve sleeve 20 is fitted to the inner peripheral wall of the fourth cavity 101. The end of the valve sleeve 20 facing the control port Y abuts against the stepped surface connecting the fourth cavity 101 and the fifth cavity 102. When the floating core 21 moves within the valve sleeve 20, the position of the entire valve sleeve 20 remains unchanged. When the floating core 21 moves to the right under the push of the elastic member 31, the frustum moves towards the stepped surface connecting the fifth cavity 102 and the sixth cavity 103. In the first position, there is a certain distance between the frustum and the end face of the fifth cavity 102, and the flow gap area between the frustum and the fifth cavity 102 is the largest. At this time, the hydraulic oil flow rate through this flow gap is the largest. When the floating core 21 moves to the second position, the frustum and the end face of the fifth cavity 102 abut against each other. At this time, the flow gap area between the frustum and the fifth cavity 102 is the smallest, and the hydraulic oil flow rate through this flow gap is the smallest. Thus, the output flow rate of the control port Y can be adjusted by the movement of the floating core 21.

[0029] like Figure 6As shown, an oil passage 23 is provided on the outer periphery of the frustum portion. This oil passage 23 is inclined and communicates with the third cavity 203. The oil passage 23 compensates for the hydraulic oil flow between the frustum portion 2121 and the valve body 100. Hydraulic oil entering from the third cavity 203 flows through the channel formed between the oil passage 23 and the valve body 100 to the control port Y. Another portion flows directly out from the inner hole 22 and acts on the control piston. When the floating core 21 is in... Figure 2 At position L1, the oil flow area to control port Y is at its maximum. The effective flow rate of the hydraulic oil output from control port Y can be understood as the sum of the direct output flow rate of inner hole 22 and the flow rate of the passage between oil passage 23 and valve body 100. As the floating core 21 moves to the right... Figure 3 At position L2, the oil flow area to the control port Y is minimized. That is, the position of the floating core 21 determines the oil flow area of ​​the control port Y. During the process from L1 to L2, the oil flow area of ​​the control port Y gradually decreases, thereby achieving a fast response while ensuring continuous and stable output.

[0030] In some embodiments, the pilot control valve further includes an inlet connector 50 inserted into the first valve chamber 10. The inlet connector 50 and the valve sleeve 20 are spaced apart at the ends opposite to the floating core 21. The inlet connector 50 forms an inlet channel communicating with the first valve chamber 10, and a third damper 34 is provided inside the inlet connector 50. The third damper 34 is in the form of a filter screen. The end of the inlet connector 50 has an inlet port X, and an inlet channel is axially formed inside the inlet connector 50. Hydraulic oil entering from the inlet port X can flow into the first valve chamber 10 along the inlet channel. By providing the third damper 34 inside the inlet connector 50, the third damper 34 filters the hydraulic oil before it enters the first valve chamber 10, reducing pressure fluctuations at the inlet port X, thereby ensuring rapid response and smooth operation of the actuator.

[0031] In some embodiments, the valve body 100 is further provided with a pressure-dividing oil passage 38 that is perpendicular to and connected to the central axis of the first valve chamber 10. The pressure-dividing oil passage 38 is connected to an external hydraulic oil tank through a pipeline. The pressure-dividing oil passage 38 is provided with a fourth damper 35 and a blocking ball 37. The pressure-dividing oil passage 38 is used to divert the hydraulic oil in the first valve chamber 10, and the blocking ball 37 is used to connect or block the oil passage between the pressure-dividing oil passage 38 and the first valve chamber 10.

[0032] In this embodiment, such as Figure 5 As shown, the pressure-dividing oil circuit 38 is configured corresponding to the fourth chamber 101, and the valve sleeve 20 has an oil outlet 204, which is used to connect the third chamber 203 and the pressure-dividing oil circuit 38. Figures 2 to 4As shown by the arrows illustrating the hydraulic oil flow, when the hydraulic oil pressure entering from the inlet port X of the inlet connector 50 fluctuates more significantly, the hydraulic oil, filtered by the third damper 34, enters the first valve chamber 10 from the outlet chamber of the inlet connector 50, then passes through the second damper 33 into the second valve chamber. A portion of the hydraulic oil enters the pressure-dividing oil circuit 38 through the outlet hole 204 on the valve sleeve 20, thereby pushing the blocking ball 37 towards the fourth damper 35. This connects the pressure-dividing oil circuit 38 and the second valve chamber through the outlet hole 204, meaning the pressure-dividing oil circuit 38 and the first valve chamber 10 are connected. The hydraulic oil in the pressure-dividing oil circuit 38 enters the external hydraulic oil tank through a pipeline, thus achieving pressure division at the inlet port X. The remaining hydraulic oil enters the inner hole 22 of the floating core 21 to drive the opening of the balance valve.

[0033] In some embodiments, the pressure-distributing oil circuit 38 includes a first pressure-distributing chamber 381, a second pressure-distributing chamber 382, ​​and a third pressure-distributing chamber 383 that are sequentially connected and have progressively increasing inner diameters. The third pressure-distributing chamber 383 is connected to the first valve chamber 10. The blocking ball 37 is located within the second pressure-distributing chamber 382 and has an outer diameter larger than the inner diameter of the first pressure-distributing chamber 381. Figure 7 As shown, the fourth damper 35 has a pressure dividing hole 36 along the axial direction and includes a first damping part 351, a second damping part 352 and a third damping part 353 connected in sequence. The third damping part 353 has a notch that communicates with the pressure dividing hole 36. The first damping part 351 is located in the first pressure dividing cavity 381 and its outer diameter is larger than the inner diameter of the second pressure dividing cavity 382. The second damping part 352 and the third damping part 353 are both located in the second pressure dividing cavity 382. The hydraulic oil flowing in from the third pressure dividing cavity 383 is used to apply a linear driving force to the blocking ball 37 so that the blocking ball 37 moves and abuts against the end face of the notch.

[0034] In this embodiment, the blocking ball 37 is a steel ball with an outer diameter larger than the inner diameter of the notch. Initially, because the outer diameter of the steel ball is larger than the inner diameter of the first pressure-dividing chamber 381, the steel ball is positioned at the connection between the first and second pressure-dividing chambers 381 and 382, ​​separating them. When the steel ball enters the first pressure-dividing chamber 381 through the oil outlet 204, it pushes the steel ball towards the fourth damping 35 in a linear motion and abuts against the end face of the notch. This connects the first and second pressure-dividing chambers 381 and 382, ​​allowing the hydraulic oil from the oil outlet 204 to pass through the first pressure-dividing chamber 381 into the second pressure-dividing chamber 382 and then flow through the pressure-dividing hole 36 of the fourth damping 35 from the outer end face of the notch. Since the pressure-dividing hole 36 is connected to an external hydraulic oil tank via a pipeline, the hydraulic oil in the pressure-dividing hole 36 can flow into the hydraulic oil tank to achieve pressure division.

[0035] In some embodiments, the valve body 100 is further provided with a bypass channel 39 communicating with the third pressure dividing chamber 383. The bypass channel 39 extends from the third pressure dividing chamber 383 to the side of the valve body 100 facing the control valve 40 and has a bypass port L. When the hydraulic oil pressure at the inlet port X is too high, part of the hydraulic oil entering the pressure dividing oil circuit 38 is discharged from the pressure dividing hole 36, and the other part flows out from the bypass channel 39 communicating with the pressure dividing oil circuit 38, thereby achieving the purpose of pressure dividing of the hydraulic oil at the inlet port X.

[0036] like Figure 1 As shown, a second aspect of this application provides a hydraulic control system, including a control valve 40 and a pilot control valve as described above. The control valve 40 can be a balance valve, such as... Figures 2 to 4 As shown, this pilot control valve is used for pilot control of a balancing valve. Of course, the pilot control valve of this invention is not limited to pilot control of balancing valves; similar applications also fall under this invention. The actuator can be a hoisting mechanism, a luffing mechanism, etc.

[0037] A third aspect of this application provides a working machine, including the hydraulic control system described above. The working machine can be a crane, excavator, or other machinery commonly found in the prior art. Since this working machine employs all embodiments of the aforementioned hydraulic control system, it possesses all the beneficial effects brought about by the hydraulic control system, which will not be elaborated upon here.

[0038] In the description of this application, it should be understood that 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. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this application, unless otherwise expressly 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 components; 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 expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0040] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. 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.

[0041] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A pilot control valve characterized by, include: The valve body assembly has a first valve chamber (10) inside. One end of the valve body assembly is used to connect to the control valve (40). The valve body assembly has a control port (Y) at one end facing the control valve (40). The valve body assembly includes a valve body (100) and a valve sleeve (20) located in the first valve chamber (10). A floating valve core is located in the first valve cavity (10) and includes a floating core body (21). One end of the floating core body (21) is movably inserted into the valve sleeve (20), and the other end can be movably inserted through the control port (Y). The pressure divider assembly includes an elastic element (31) and a first damper (32). The elastic element (31) is elastically connected between the inner wall of the valve sleeve (20) and the floating core (21). The first damper (32) is inserted into the floating core (21). One end of the floating core (21) away from the elastic element (31) is used to abut against the control piston of the control valve (40). Hydraulic oil flowing from the control port (Y) is used to drive the control piston to move, and the elastic element (31) is used to drive the floating core (21) to move axially and change the distance between the floating core (21) and the valve body assembly, so as to adjust the hydraulic oil output flow of the control port (Y). The pilot control valve also includes an oil inlet connector (50) inserted into the first valve chamber (10). The oil inlet connector (50) and the valve sleeve (20) are arranged at a distance from one end of the floating core (21). The oil inlet connector (50) forms an oil inlet channel communicating with the first valve chamber (10). The oil inlet connector (50) is provided with a third damping (34).

2. The pilot control valve according to claim 1, characterized in that The valve sleeve (20) has a second valve cavity, which includes a first cavity (201), a second cavity (202) and a third cavity (203) connected sequentially along the axial direction. The elastic element (31) is located in the second cavity (202) and its two ends are respectively connected to the end face of the second cavity (202) and the floating core (21). The floating core (21) is movably located in the third cavity (203).

3. The pilot control valve according to claim 2, characterized in that The first cavity (201) is provided with a second damper (33), the second damper (33) includes a first end cap and a damping body connected to the first end cap. The first end cap is located at the end of the valve sleeve (20) away from the floating core (21) and its outer diameter is larger than the inner diameter of the first cavity (201). The damping body is located inside the first cavity (201).

4. The pilot control valve of claim 2, wherein The first valve chamber (10) includes a fourth chamber (101), a fifth chamber (102), and a sixth chamber (103) that are connected in sequence along the axial direction and whose inner diameters decrease in sequence. The valve sleeve (20) is located in the fourth chamber (101). The floating core (21) includes a large-diameter portion (211), a valve seat (212), and a small-diameter portion (213) that are connected in sequence along the axial direction. The valve seat includes a frustum portion (2121) and an annular portion (2122). The outer diameter of the frustum portion (2121) increases from the outer diameter towards the outer diameter. The outer diameter of the ring portion (2122) decreases from the large diameter portion (211) in the direction of the large diameter portion (2121). The outer diameter of the ring portion (2122) is equal to the outer diameter of the end of the frustum portion (2121) and smaller than the outer diameter of the small diameter portion (213). The large diameter portion (211) is located within the fifth cavity (102). The maximum outer diameter of the frustum portion (2121) is smaller than the inner diameter of the fifth cavity (102) and larger than the inner diameter of the sixth cavity (103). The small diameter portion (213) is located within the sixth cavity (103).

5. The pilot control valve according to claim 4, characterized in that An oil passage (23) is provided on the outer periphery of the frustum portion (2121), and the oil passage (23) is connected to the third cavity (203).

6. The pilot control valve according to any one of claims 2 to 5, characterized in that The valve body (100) is also provided with a pressure-dividing oil passage (38) that is perpendicular to and connected to the central axis of the first valve chamber (10). The pressure-dividing oil passage (38) is connected to an external hydraulic oil tank through a pipeline. The pressure-dividing oil passage (38) is provided with a fourth damper (35) and a blocking ball (37). The pressure-dividing oil passage (38) is used to divert the hydraulic oil in the first valve chamber (10). The blocking ball (37) is used to connect or block the oil passage between the pressure-dividing oil passage (38) and the first valve chamber (10).

7. The pilot control valve according to claim 6, characterized in that The pressure distribution oil circuit (38) includes a first pressure distribution chamber (381), a second pressure distribution chamber (382), and a third pressure distribution chamber (383) that are connected in sequence and have increasing inner diameters. The third pressure distribution chamber (383) is connected to the first valve chamber (10). The barrier ball (37) is located in the second pressure distribution chamber (382) and its outer diameter is larger than the inner diameter of the first pressure distribution chamber (381). The fourth damper (35) has a pressure dividing hole (36) along the axial direction and includes a first damping part (351), a second damping part (352) and a third damping part (353) connected in sequence. The third damping part (353) has a notch that communicates with the pressure dividing hole (36). The first damping part (351) is located in the first pressure dividing cavity (381) and its outer diameter is larger than the inner diameter of the second pressure dividing cavity (382). The second damping part (352) and the third damping part (353) are both located in the second pressure dividing cavity (382). The hydraulic oil flowing in from the third pressure dividing cavity (383) is used to apply a linear driving force to the barrier ball (37) so that the barrier ball (37) moves and abuts against the end face of the notch.

8. The pilot control valve according to claim 7, characterized in that The valve body (100) is also provided with a bypass channel (39) that communicates with the third pressure chamber (383). The bypass channel (39) extends from the third pressure chamber (383) to the side of the valve body (100) facing the control valve (40) and has a bypass port (L).

9. A hydraulic control system characterized by, Includes a control valve (40) and a pilot control valve according to any one of claims 1 to 8.

10. A type of operating machinery, characterized in that, Includes the hydraulic control system according to claim 9.

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