A new bidirectional balancing valve

Abstract

The application discloses a novel bidirectional balance valve, and belongs to the technical field of balance valves. The bidirectional balance valve comprises a valve body, two valve cavities are symmetrically arranged in the valve body, an overflow valve assembly and a one-way valve assembly are arranged in the valve cavities, the overflow valve assembly comprises a valve seat fixed on the valve body, a valve core movably arranged in the valve cavity and a pressure regulating spring arranged between the valve core and the valve seat, the one-way valve assembly comprises a one-way valve sleeve movably arranged in the valve cavity and a one-way valve spring connected between the one-way valve sleeve and the inner wall of the valve cavity, a front section of the valve seat is located at the communication position of a V oil port and the valve cavity, and a throttling oil hole in communication with the V oil port is arranged on the outer circumferential surface of the end of the front section of the valve seat, which is away from the middle section of the valve seat. The application can effectively reduce load vibration, effectively improve micro-control performance, better match different flow load requirements, improve working stability and safety, and reduce the machining and manufacturing difficulty of the balance valve by adopting a large-diameter small-passage.

Description

Technical Field

[0001] This invention relates to the technical field of balancing valves, and more particularly to a novel bidirectional balancing valve. Background Technology

[0002] Construction machinery operates under complex conditions. In its hydraulic transmission system, a balance valve is often used to prevent stalling or overspeeding. In hybrid boom aerial work platforms, the load shifts between positive and negative directions during boom lifting as the luffing angle changes. Therefore, a two-way balance valve is used to prevent the danger of cylinder stalling or overspeeding during rotation.

[0003] The bidirectional balance valve consists of a pair of symmetrically arranged balance valves with identical structures. Each valve's remote control port is connected to the inlet of the opposite valve. The check valve sleeve and the main valve core of the balance valve together form a throttling control port, with the two valve core springs arranged facing each other. When the amplitude angle increases, pressurized oil enters from port C1, opening the left check valve sleeve and pushing the cylinder piston rod to extend and drive the boom to rotate. The return flow from the small cylinder chamber enters port V2, acting on the right main valve core. Together with the control oil from the remote control port, this drives the valve core to move. Due to the spring force of the main valve core, port V2 always maintains a back pressure, thus ensuring the smoothness of the cylinder speed during positive and negative load switching.

[0004] Regarding the aforementioned prior art, the inventors believe that existing balancing valves are prone to low-frequency vibrations under heavy loads, resulting in poor operational stability and safety. Summary of the Invention

[0005] To address the issue of low-frequency vibration in balancing valves under heavy loads, improve their operational stability and safety, reduce the manufacturing difficulty of balancing valves, and enable them to meet different flow load requirements, this invention provides a novel bidirectional balancing valve.

[0006] The technical solution adopted by this invention to solve its technical problem is: a novel bidirectional balance valve, comprising a valve body, wherein two valve chambers are symmetrically opened within the valve body, and each valve chamber has a V-port for connection to a system pipeline and a C-port for connection to a hydraulic cylinder on its inner wall. Each valve chamber is provided with an overflow valve assembly and a one-way valve assembly. The overflow valve assembly includes a valve seat fixed to the valve body, a valve core movably installed in the valve chamber, and a pressure regulating spring connecting the valve core and the valve seat. The one-way valve assembly includes a one-way valve sleeve movably installed in the valve chamber and a one-way valve spring connecting the one-way valve sleeve and the inner wall of the valve chamber.

[0007] The valve seat includes an integrally connected front section, middle section, and rear section. The front section and middle section are inserted into the valve body. The middle section is threaded to the valve body. The rear section is located outside the valve body and abuts against the outer wall of the valve body. The front section is located at the connection between the V-port and the valve cavity. A throttling oil passage is opened on the outer peripheral surface of the front section away from the middle section, which communicates with the V-port.

[0008] The valve core (5) includes an integrally connected front section (51), middle section (52), and rear section (53). The valve core (5) has a control oil hole (54) along its axis. A transition section is formed at the connection between the middle section (52) and the rear section (53). The outer circumferential surface of the transition section has a sealing outer cone surface (55) and a through-diameter inner ring surface (56). The one-way valve sleeve (7) near the valve seat (4) can fit tightly against the sealing outer cone surface (55) under the action of the one-way valve spring (8). The inner wall of the one-way valve sleeve (7) near the valve seat (4) has a through-diameter outer ring surface (71). When the one-way valve sleeve (7) is separated from the valve core (5), the through-diameter inner ring surface (56) and the through-diameter outer ring surface (71) form an oil passage (72).

[0009] When oil enters through the left V port, the hydraulic oil enters the left valve chamber (3) and splits into two paths. One path passes through the lateral oil hole (413) of the valve seat (4) and enters the control oil hole (54). When the oil pressure reaches the set pressure, the push rod (2) is pushed open. The push rod (2) pushes the valve core (5) of the right valve chamber (3) to move to the right, so that the valve core (5) of the right valve chamber (3) is separated from the one-way valve sleeve (7). Then the hydraulic oil in the rod chamber or rodless chamber of the cylinder enters the right valve chamber (3) through the right C port, and flows out from the right V port through the oil passage (72) between the one-way valve sleeve (7) and the valve core (5) and the throttling flow hole (411). The other path passes through the throttling flow hole (411) and directly pushes the one-way valve sleeve (7) in the left valve chamber (3) to the right, and then enters the rodless chamber or rod chamber of the cylinder through the left C port.

[0010] Furthermore, a sealing inner conical surface is formed on the inner wall of the opening at one end of the valve seat that penetrates the valve body. The inner diameter of the sealing inner conical surface increases progressively towards the one-way valve sleeve. The end of the one-way valve sleeve away from the one-way valve spring can fit tightly against the sealing inner conical surface.

[0011] Furthermore, the rear section of the valve core passes through the inner cavity of the valve seat, the middle section of the valve core passes through the one-way valve sleeve, and the outer diameter of the middle section of the valve core is smaller than that of the rear section of the valve core.

[0012] Furthermore, the inner diameter of the middle section of the valve seat is smaller than the inner diameter of the front section of the valve seat, so that the inner wall at the connection between the middle section and the front section of the valve seat forms a limited-position stepped inclined surface.

[0013] The beneficial effects of this invention:

[0014] The novel bidirectional balancing valve of the present invention has a throttling oil passage in the valve seat. Compared with the existing structure in which the front end face of the valve seat is opened with several U-shaped slots to connect the oil port and the valve cavity, when the load is large, the dynamic balancing property of the bidirectional balancing valve is utilized to increase the back pressure of the actuator through the throttling oil passage, which can reduce vibration and avoid the impact caused by the excessive flow at the moment the balancing valve is opened. At this time, the valve core is in a dynamic process of unbalanced force, which further improves the smoothness of movement.

[0015] Furthermore, a sealing inner cone surface is provided along the opening at the front of the valve seat to cooperate with the one-way valve sleeve for reliable sealing, so as to ensure that hydraulic oil can flow smoothly from the throttling oil passage. Moreover, the valve seat structure design of the present invention has higher strength and is easier to process than the existing valve seat structure.

[0016] An oil passage can be formed between the inner annular surface of the one-way valve sleeve and the outer annular surface of the valve core. Therefore, the influence of changes in the flow cross-sectional area with the valve opening is minimal. During the movement of the valve core or one-way valve sleeve, the oil passage remains constant and stable, ensuring stable oil flow. Furthermore, the flow rate of this balancing valve can be adjusted by controlling the diameter during machining to match the operating requirements of different loads. Especially in low-flow applications, this invention eliminates the need to modify the overall dimensions of the internal valve core and one-way valve sleeve, effectively reducing manufacturing difficulty. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view of the overall structure of an embodiment of the present invention.

[0018] Figure 2 This is a partial sectional view of the valve body structure in an embodiment of the present invention.

[0019] Figure 3 This is a cross-sectional view used to illustrate the valve seat structure in an embodiment of the present invention.

[0020] Figure 4 yes Figure 2 A magnified view of part A in the middle.

[0021] Figure 5 This is a cross-sectional view of the valve core in an embodiment of the present invention.

[0022] Figure 6 This is a cross-sectional view of the one-way valve sleeve in an embodiment of the present invention.

[0023] Figure 7 This is a hydraulic schematic diagram of an embodiment of the present invention.

[0024] Figure 8This is a structural cross-sectional view of an existing valve seat.

[0025] In the diagram: 1. Valve body; 2. Push rod; 3. Valve cavity; 31. V1 oil port; 32. V2 oil port; 33. C1 oil port; 34. C2 oil port; 4. Valve seat; 41. Front section of valve seat; 411. Throttling oil passage; 412. Sealing inner conical surface; 413. Lateral oil hole; 414. U-shaped groove; 42. Middle section of valve seat; 421. Limiting step inclined surface; 43. Rear section of valve seat; 44. Pressure adjusting screw; 45. Locking nut; 46. Spring abutment; 5. Valve core; 51. Front section of valve core; 52. Middle section of valve core; 53. Rear section of valve core; 54. Control oil hole; 55. Sealing outer conical surface; 56. Inner annular surface of the bore; 6. Pressure adjusting spring; 7. One-way valve sleeve; 71. Outer annular surface of the bore; 72. Oil passage; 8. One-way valve spring; 9. Gasket. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0027] This invention discloses a novel bidirectional balancing valve.

[0028] Reference Figure 1 and Figure 2 A novel bidirectional balance valve includes a valve body 1, within which two valve chambers 3 are symmetrically arranged, and a sliding cavity is located between and connecting the two valve chambers 3. A push rod 2 is slidably connected within the sliding cavity. Each valve chamber 3 has a V-port for connection to a system pipeline and a C-port for connection to a hydraulic cylinder on its inner wall. In this embodiment, the ports connecting to the left valve chamber 3 are designated as V1 port 31 and C1 port 33, and the ports connecting to the right valve chamber 3 are designated as V2 port 32 and C2 port 34. The left and right directions described in this embodiment are... Figure 1 The orientation of the structure shown is for reference.

[0029] Reference Figures 2 to 4 Each valve chamber 3 is equipped with an overflow valve assembly and a check valve assembly, wherein the overflow valve assembly includes a valve seat 4, a valve core 5, and a pressure regulating spring 6.

[0030] The valve seat 4 includes an integrally connected front section 41, middle section 42, and rear section 43. The rear section 43 is located outside the valve body 1 and abuts against the outer wall of the valve body 1. A pressure adjusting screw 44 is provided through the rear section 43. One end of the pressure adjusting screw 44 that enters the inner cavity of the valve seat 4 is connected to a spring abutment 46. A locking nut 45 is provided on the outer side of the rear section 43. The locking nut 45 is threaded to the outside of the pressure adjusting screw 44 and abuts against the outer wall of the rear section 43.

[0031] The front section 41 and the middle section 42 of the valve seat are inserted into the valve body 1. The middle section 42 of the valve seat is threadedly connected to the valve body 1. The front section 41 of the valve seat is located at the connection between the V oil port and the valve cavity 3. One end of the valve core 5 slides through the inner cavity of the front section 41 of the valve seat. The pressure regulating spring 6 is located in the inner cavity of the valve body 1. One end of the pressure regulating spring 6 is connected to the spring abutment 46, and the other end is connected to the valve core 5. The inner diameter of the inner cavity of the middle section 42 of the valve seat is smaller than the inner diameter of the inner cavity of the front section 41 of the valve seat, so that the inner wall at the connection between the middle section 42 of the valve seat and the front section 41 of the valve seat forms a limiting stepped inclined surface 421.

[0032] A throttling oil passage 411 communicating with the V oil port is provided on the outer peripheral surface of the end of the valve seat front section 41 away from the valve seat middle section 42; the axis of the throttling oil passage 411 is perpendicular to the axis of the valve seat front section 41; in this embodiment, there are two throttling oil passages 411, and the two throttling oil passages 411 are symmetrically opened on both sides of the valve seat front section 41 along the axis of the valve seat front section 41.

[0033] Reference Figures 2 to 6 The one-way valve assembly includes a one-way valve sleeve 7, a one-way valve spring 8, and a gasket 9. The one-way valve sleeve 7 is movably connected to the valve cavity 3 and is located at the front end of the valve seat 4 that penetrates the valve body 1. The one-way valve spring 8 is located on the side of the one-way valve sleeve 7 away from the valve seat 4. One end of the one-way valve spring 8 penetrates into the one-way valve sleeve 7 and abuts against the stepped surface of the inner cavity of the one-way valve sleeve 7. The other end of the one-way valve spring 8 abuts against the stepped surface in the valve cavity 3 through the gasket 9. The valve core 5 is movably installed in the valve cavity 3. The one-way valve sleeve 7 and the valve core 5 can be tightly fitted together under the action of the corresponding one-way valve spring 8 and the pressure regulating spring 6 to cut off the oil circuit.

[0034] A sealing inner cone surface 412 is formed on the inner wall of the front opening of the valve seat front section 41. The inner diameter of the sealing inner cone surface 412 increases in the direction close to the one-way valve sleeve 7. The end of the one-way valve sleeve 7 away from the one-way valve spring 8 can fit tightly against the sealing inner cone surface 412.

[0035] Reference Figure 5 The valve core 5 includes a front section 51, a middle section 52, and a rear section 53. The valve core 5 has a control oil hole 54 along its axis. The rear section 53 passes through the inner cavity of the front section 41 of the valve seat, and the middle section 52 passes through the one-way valve sleeve 7. The outer diameter of the middle section 52 is smaller than that of the rear section 53, so that a transition section is formed at the connection between the middle section 52 and the rear section 53. The outer circumferential surface of the transition section has a sealing outer cone surface 55 and a through-diameter inner ring surface 56. The sealing outer cone surface 55 is located at the end of the through-diameter inner ring surface 56 near the valve seat 4.

[0036] Reference Figures 4 to 6The end of the one-way valve sleeve 7 near the valve seat 4 can be tightly fitted against the sealing outer cone surface 55 under the action of the one-way valve spring 8 to cut off the oil circuit. The inner wall of the end of the one-way valve sleeve 7 near the valve seat 4 forms a through-hole outer annular surface 71. The length of the through-hole outer annular surface 71 is less than the length of the through-hole inner annular surface 56. When the one-way valve sleeve 7 is separated from the valve core 5 under the action of oil pressure, an oil passage 72 can be formed between the through-hole inner annular surface 56 and the through-hole outer annular surface 71.

[0037] The working principle of a novel bidirectional balance valve in this embodiment is as follows: Taking the C2 port 34 connected to the rod chamber of the cylinder and the C1 port 33 connected to the rodless chamber of the cylinder as an example, when oil enters the V1 port 31, the hydraulic oil enters the left valve chamber 3 and is divided into two paths: one path enters the control oil port 54 through the lateral oil hole 413 of the valve seat 4. When the oil pressure reaches the set pressure, it pushes open the push rod 2. The push rod 2 pushes the valve core 5 of the right valve chamber 3 to move to the right, thereby disengaging the valve core 5 of the right valve chamber 3 from the one-way valve sleeve 7. Then, the hydraulic oil in the rod chamber of the cylinder enters the right valve chamber 3 through the C2 port 34, and flows out from the V2 port 32 through the oil passage 72 between the one-way valve sleeve 7 and the valve core 5 and the throttling flow hole 411; the other path passes through the throttling flow hole 411, directly pushes open the one-way valve sleeve 7 in the left valve chamber 3 to the right, and then enters the rodless chamber of the cylinder through the C1 port.

[0038] Conversely, when oil enters from port V2 32, the hydraulic oil enters the right valve chamber 3 and passes through the lateral oil hole 413 into the control oil hole 54, pushing open the push rod 2. The push rod 2 pushes the valve core 5 of the left valve chamber 3 to move to the left, causing the valve core 5 of the left valve chamber 3 to disengage from the one-way valve sleeve 7. Then, the hydraulic oil in the rodless chamber of the cylinder enters the left valve chamber 3 through port C1 33, and flows out from port V1 31 through the oil passage 72 between the one-way valve sleeve 7 and the valve core 5 and the throttling flow hole 411. Another path passes through the throttling flow hole 411, directly pushing the one-way valve sleeve 7 in the right valve chamber 3 to the left, and then enters the rod chamber of the cylinder through the C2 oil hole.

[0039] This cycle repeats, allowing the piston rod of the hydraulic cylinder to move left and right or up and down to perform the required actions. When both oil ports V1 (31) and V2 (32) are simultaneously cut off, the hydraulic cylinder can be locked, keeping the load stable. Because the bidirectional balance valve implements linkage control on the two chambers of the hydraulic cylinder, the oil inlet and outlet of the two chambers of the hydraulic cylinder are always in a balanced state, enabling the actuator carried by the hydraulic cylinder to operate smoothly.

[0040] In this embodiment, the front section 41 of the valve seat is provided with a throttling oil passage 411, which is different from the existing type. Figure 8The valve seat 4 shown has several U-shaped slots 414 on its front end face to connect the oil port and the valve cavity 3. When the load is large, the dynamic balance of the bidirectional balance valve is used to increase the back pressure of the actuator by throttling the oil passage 411, which can reduce vibration and avoid the impact caused by the excessive flow at the moment the balance valve is opened. At this time, the valve core 5 is in a dynamic process of unbalanced force, which further improves the smoothness of movement.

[0041] Furthermore, a sealing inner cone surface 412 is provided along the opening of the valve seat front section 41 to cooperate with the one-way valve sleeve 7 for reliable sealing, so as to ensure that hydraulic oil can flow smoothly from the throttling oil passage 411. Moreover, the valve seat 4 of the present invention has higher strength and is easier to process than the existing valve seat structure.

[0042] An oil passage 72 can be formed between the outer annular surface 71 of the inner wall of the one-way valve sleeve 7 and the inner annular surface 56 of the outer wall of the valve core 5. Therefore, the influence of changes in the flow cross-sectional area with the valve opening is very small. During the movement of the valve core 5 or the one-way valve sleeve 7, the oil passage 72 remains constant and stable, thus ensuring the stability of the oil flow. Furthermore, the flow rate of this balancing valve can be adjusted by controlling the size of the bore through machining to match the working requirements of different loads. Especially in low-flow applications, this invention eliminates the need to modify the overall dimensions of the internal valve core 5 and the one-way valve sleeve 7, effectively reducing manufacturing difficulty.

[0043] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A novel bidirectional balancing valve, characterized in that: The system includes a valve body (1), which has two symmetrically arranged valve chambers (3). Each valve chamber (3) has a V-port for connecting to a system pipeline and a C-port for connecting to a cylinder. Each valve chamber (3) has an overflow valve assembly and a one-way valve assembly. The overflow valve assembly includes a valve seat (4) fixed on the valve body (1), a valve core (5) movably installed in the valve chamber (3), and a pressure regulating spring (6) connecting the valve core (5) and the valve seat (4). The one-way valve assembly includes a one-way valve sleeve (7) movably installed in the valve chamber (3) and a one-way valve spring (8) connecting the one-way valve sleeve (7) and the inner wall of the valve chamber (3). The valve seat (4) includes an integrally connected front section (41), middle section (42), and rear section (43). The front section (41) and middle section (42) are inserted into the valve body (1). The middle section (42) is threaded to the valve body (1). The rear section (43) is located outside the valve body (1) and abuts against the outer wall of the valve body (1). The front section (41) is located at the connection between the V oil port and the valve cavity (3). The outer circumferential surface of the front section (41) away from the middle section (42) is provided with a throttling oil passage (411) communicating with the V oil port. The valve core (5) includes an integrally connected front section (51), middle section (52), and rear section (53). The valve core (5) has a control oil hole (54) along its axis. A transition section is formed at the connection between the middle section (52) and the rear section (53). The outer circumferential surface of the transition section has a sealing outer cone surface (55) and a through-diameter inner ring surface (56). The one-way valve sleeve (7) near the valve seat (4) can fit tightly against the sealing outer cone surface (55) under the action of the one-way valve spring (8). The inner wall of the one-way valve sleeve (7) near the valve seat (4) has a through-diameter outer ring surface (71). When the one-way valve sleeve (7) is separated from the valve core (5), the through-diameter inner ring surface (56) and the through-diameter outer ring surface (71) form an oil passage (72). When oil enters through the left V port, the hydraulic oil enters the left valve chamber (3) and splits into two paths. One path passes through the lateral oil hole (413) of the valve seat (4) and enters the control oil hole (54). When the oil pressure reaches the set pressure, the push rod (2) is pushed open. The push rod (2) pushes the valve core (5) of the right valve chamber (3) to move to the right, so that the valve core (5) of the right valve chamber (3) is separated from the one-way valve sleeve (7). Then the hydraulic oil in the rod chamber or rodless chamber of the cylinder enters the right valve chamber (3) through the right C port, and flows out from the right V port through the oil passage (72) between the one-way valve sleeve (7) and the valve core (5) and the throttling flow hole (411). The other path passes through the throttling flow hole (411) and directly pushes the one-way valve sleeve (7) in the left valve chamber (3) to the right, and then enters the rodless chamber or rod chamber of the cylinder through the left C port.

2. The novel bidirectional balancing valve according to claim 1, characterized in that: The valve seat (4) has a sealing inner cone surface (412) formed on the inner wall of the opening at one end of the valve body (1). The inner diameter of the sealing inner cone surface (412) increases in the direction close to the one-way valve sleeve (7). The end of the one-way valve sleeve (7) away from the one-way valve spring (8) can fit and abut against the sealing inner cone surface (412).

3. The novel bidirectional balancing valve according to claim 1, characterized in that: The rear section (53) of the valve core passes through the inner cavity of the valve seat (4), and the middle section (52) of the valve core passes through the one-way valve sleeve (7). The outer diameter of the middle section (52) of the valve core is smaller than that of the rear section (53).

4. A novel bidirectional balancing valve according to claim 1, characterized in that: The inner diameter of the middle section (42) of the valve seat is smaller than the inner diameter of the front section (41) of the valve seat, so that the inner wall at the connection between the middle section (42) and the front section (41) of the valve seat forms a limited step slope (421).

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