Balancing valves and engineering machinery with them

Abstract

This invention provides a balancing valve and engineering machinery having the same. The balancing valve includes: a valve body with a first oil port, and a second oil port and a third oil port located on both sides of the first oil port; a valve core movably disposed within the valve body, with a connecting groove in the middle of the valve core, the connecting groove being adapted to connect the first oil port and the second oil port, or adapted to connect the first oil port and the third oil port, and a buffer groove being disposed on the axial end face of the connecting groove; and an elastic buffer structure disposed between one side of the valve core and the valve body. The technical solution of this invention solves the defect in the prior art where the balancing valve is prone to shaking during the descent of the hoisting mechanism.

Description

Technical Field

[0001] This invention relates to the field of hydraulic components, specifically to a balance valve and engineering machinery having the same. Background Technology

[0002] Currently, lifting machinery primarily uses winch mechanisms to lift and lower heavy objects to complete various practical work processes. The smoothness of lifting and lowering is a crucial indicator of crane operability. Smoothness is mainly categorized into speed stability and vibration stability. This key indicator is typically controlled by a motor balance valve.

[0003] During the descent, the winch mechanism operates through a combination of powered and gravity-driven descent. While powered descent is highly efficient, the load force varies significantly during luffing. Excessive winch descent speed causes a momentary drop in pressure at the balance valve port, leading to a decrease in the balance valve's control pressure and a reduction in its opening. Conversely, a slower descent speed causes a momentary increase in pressure at the balance valve port. Consequently, the balance valve opening is constantly influenced by the control pressure entering the port, a process that can easily cause winch descent vibration. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect that the balance valve of the hoisting mechanism in the prior art is prone to shaking when falling, thereby providing a balance valve and engineering machinery having it.

[0005] To address the aforementioned problems, the present invention provides a balancing valve, comprising: a valve body having a first oil port and a second oil port and a third oil port located on both sides of the first oil port; a valve core movably disposed within the valve body, the valve core having a connecting groove in its middle portion, the connecting groove being adapted to connect the first oil port with the second oil port, or adapted to connect the first oil port with the third oil port, and a buffer groove being disposed on the axial end face of the connecting groove; and an elastic buffer structure disposed between one side of the valve core and the valve body.

[0006] Optionally, the valve body is provided with a first mounting cavity and a second mounting cavity that are interconnected. The valve core is disposed in the first mounting cavity, and an elastic buffer structure is disposed in the second mounting cavity. The elastic buffer structure includes: a first pressure plate disposed on the side of the second mounting cavity facing the first mounting cavity; a second pressure plate disposed on the side of the second mounting cavity away from the first mounting cavity; and an elastic element disposed between the first pressure plate and the second pressure plate. A guide post is provided at the end of the valve core facing the second mounting cavity. The guide post passes through the first pressure plate and connects to the second pressure plate. An anti-detachment structure is provided between the guide post and the second pressure plate.

[0007] Optionally, the first pressure plate includes a first guide cylinder and a first annular protrusion connected to the edge of the first guide cylinder. The guide post passes through the first guide cylinder, and the diameter of the first mounting cavity is larger than the diameter of the second mounting cavity, so that a stepped surface is formed between the first mounting cavity and the second mounting cavity. The first annular protrusion mates with the stepped surface.

[0008] Optionally, the second pressure plate includes a second guide cylinder and a second annular protrusion connected to the edge of the second guide cylinder, the end of the guide post passes through the second guide cylinder, and an anti-detachment structure is disposed between the guide post and the second guide cylinder.

[0009] Optionally, the elastic element is a spring, which is sleeved outside the first guide cylinder and the second guide cylinder, and the two ends of the spring abut against the first annular convex edge and the second annular convex edge, respectively.

[0010] Optionally, the connecting groove includes a first end face and a second end face that are circumferentially opposite each other, and the buffer groove includes a first groove body and a second groove body. The first groove body is disposed on one of the first end face and the second end face, and the second groove body is disposed on the other of the first end face and the second end face. The first groove body and the second groove body are disposed opposite each other.

[0011] Optionally, the walls of the first and second tanks are curved surfaces.

[0012] Optionally, the first groove includes a first segment and a second segment connected to each other along the axial direction, the second segment being located on the side of the first segment away from the second groove, and the size of the second segment being smaller than the size of the first segment in the circumferential direction.

[0013] Optionally, there are multiple buffer slots, which are spaced apart circumferentially, wherein the first and second slots of adjacent buffer slots are positioned opposite each other.

[0014] The present invention also provides an engineering machine, including the above-mentioned balance valve.

[0015] The present invention has the following advantages:

[0016] The technical solution of this invention provides a buffer groove on the axial end face of the connecting groove. This buffer groove buffers the pressure at the first oil port, thereby reducing the impact of pressure changes on the valve core stroke. By providing an elastic buffer structure between one side of the valve core and the valve body, compared to the existing structure where springs are provided on both sides of the valve core, the installation gap is smaller, motion interference is less, and the valve core stroke can be better controlled, reducing the impact of control pressure changes on the valve core stroke. Therefore, the technical solution of this invention solves the defect in the prior art where the balance valve easily vibrates during the descent of the hoisting mechanism. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 A cross-sectional schematic diagram of the balancing valve of the present invention is shown;

[0019] Figure 2 It shows Figure 1 Enlarged view of point A in the middle;

[0020] Figure 3 It shows Figure 1 Enlarged view of point B in the middle;

[0021] Figure 4 It shows Figure 1 Enlarged view of point C in the middle;

[0022] Figure 5 It shows Figure 1 A schematic diagram of the structure at the connecting slot in the middle of the balance; and

[0023] Figure 6 It shows Figure 1 A schematic diagram of the structure of the connecting groove of the central balance valve from an axial perspective.

[0024] Explanation of reference numerals in the attached figures:

[0025] 10. Valve body; 11. First oil port; 12. Second oil port; 13. Third oil port; 20. Valve core; 21. Connecting groove; 211. First end face; 212. Second end face; 22. Guide post; 30. Buffer groove; 31. First groove body; 311. First section; 312. Second section; 32. Second groove body; 40. Elastic buffer structure; 41. First pressure plate; 411. First guide cylinder; 412. First annular protrusion; 42. Second pressure plate; 421. Second guide cylinder; 422. Second annular protrusion; 43. Elastic element; 44. Anti-detachment structure; 50. First mounting cavity; 60. Second mounting cavity; 70. Stepped surface. Detailed Implementation

[0026] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] like Figure 1 The balance valve of this embodiment includes a valve body 10, a valve core 20, and an elastic buffer structure 40. The valve body 10 has a first oil port 11, and a second oil port 12 and a third oil port 13 located on either side of the first oil port 11. The valve core 20 is movably disposed within the valve body 10, and a connecting groove 21 is provided in the middle of the valve core 20. The connecting groove 21 is adapted to connect the first oil port 11 with the second oil port 12, or to connect the first oil port 11 with the third oil port 13. A buffer groove 30 is provided on the axial end face of the connecting groove 21. The elastic buffer structure 40 is disposed between one side of the valve core 20 and the valve body 10.

[0031] Using the technical solution of this embodiment, a buffer groove 30 is provided on the axial end face of the connecting groove 21. The buffer groove 30 can buffer the pressure at the first oil port 11, thereby reducing the impact of pressure changes on the stroke of the valve core 20. By providing an elastic buffer structure 40 between one side of the valve core 20 and the valve body 10, compared with the structure of providing springs on both sides of the valve core in the prior art, the installation gap is smaller, the motion interference is smaller, and the stroke of the valve core 20 can be better controlled, reducing the impact of control pressure changes on the stroke of the valve core 20. Therefore, the technical solution of this embodiment solves the defect of the balance valve easily shaking during the fall of the hoisting mechanism in the prior art.

[0032] It should be noted that the first oil port 11 is used to connect to the main oil circuit of the hydraulic system, while the second oil port 12 and the third oil port 13 are both used to connect to the hydraulic motor. The valve core 20 can slide axially within the valve body 10. Depending on the specific operating conditions, the connecting groove 21 can connect the first oil port 11 and the second oil port 12, or it can connect the first oil port 11 and the third oil port 13. The function of the balance valve is to unload oil from the high-pressure side of the second oil port 12 and the third oil port 13.

[0033] It should be noted that the aforementioned elastic buffer structure 40 is only provided on one side of the valve core 20. In the prior art, springs are typically provided on both sides of the valve core 20; however, the double-spring structure suffers from large installation gaps and mutual interference between the two springs. In this embodiment, the elastic buffer structure 40 is provided only on one side of the valve core 20, which reduces installation gaps and motion interference, and better mitigates the impact of control pressure changes on the stroke of the valve core 20. Furthermore, the elastic buffer structure 40 can buffer the movement of the valve core 20 in both directions.

[0034] like Figure 1 As shown, in this embodiment, the valve body 10 has a first mounting cavity 50 and a second mounting cavity 60 that are interconnected. The valve core 20 is disposed in the first mounting cavity 50, and the elastic buffer structure 40 is disposed in the second mounting cavity 60. The elastic buffer structure 40 includes a first pressure plate 41, a second pressure plate 42, and an elastic element 43. The first pressure plate 41 is disposed on the side of the second mounting cavity 60 facing the first mounting cavity 50. The second pressure plate 42 is disposed on the side of the second mounting cavity 60 away from the first mounting cavity 50. The elastic element 43 is disposed between the first pressure plate 41 and the second pressure plate 42. Further, a guide post 22 is provided at the end of the valve core 20 facing the second mounting cavity 60. The guide post 22 passes through the first pressure plate 41 and connects to the second pressure plate 42. An anti-detachment structure 44 is provided between the guide post 22 and the second pressure plate 42.

[0035] According to the above structure, when the valve core 20 moves toward the second mounting cavity 60, it pushes the first pressure plate 41 toward the second pressure plate 42. At this time, the gap between the first pressure plate 41 and the second pressure plate 42 decreases, thereby compressing the elastic element 43 and buffering the movement of the valve core 20. When the valve core 20 moves away from the second mounting cavity 60, because an anti-detachment structure 44 is provided between the guide post 22 and the second pressure plate 42, the guide post 22 will drive the second pressure plate 42 toward the first pressure plate 41. At this time, the gap between the first pressure plate 41 and the second pressure plate 42 decreases, thereby compressing the elastic element 43 and buffering the movement of the valve core 20. Therefore, with the above structure, providing an elastic buffer structure 40 on only one side of the valve core 20 is sufficient to buffer the movement of the valve core 20 in both directions.

[0036] Furthermore, in this embodiment, throttle valves are provided at both ends of the valve core 20 to achieve oil inlet damping, buffer the control pressure oil source pressure, and match the oil inlet damping and bypass damping to further buffer and control the control pressure. The aforementioned guide post 22 is connected to a throttle valve.

[0037] like Figure 2 As shown, in this embodiment, the first pressure plate 41 includes a first guide cylinder 411 and a first annular protrusion 412 connected to the edge of the first guide cylinder 411. A guide post 22 passes through the first guide cylinder 411. The diameter of the first mounting cavity 50 is larger than the diameter of the second mounting cavity 60, so that a stepped surface 70 is formed between the first mounting cavity 50 and the second mounting cavity 60. The first annular protrusion 412 engages with the stepped surface 70. Specifically, a through hole is provided in the middle of the first guide cylinder 411, through which the guide post 22 passes, allowing the guide post 22 and the first guide cylinder 411 to move axially. When the valve core 20 moves toward the second mounting cavity 60, the valve core 20 abuts against the first annular protrusion 412 and pushes the first pressure plate 41 toward the second pressure plate 42, thereby reducing the distance between the first pressure plate 41 and the second pressure plate 42. When the valve core 20 moves away from the second mounting cavity 60, the first annular protrusion 412 abuts against the stepped surface 70, thereby fixing the position of the first pressure plate 41. The guide post 22 drives the second pressure plate 42 to face the first pressure plate 41 from the east through the anti-detachment structure 44, thereby reducing the distance between the first pressure plate 41 and the second pressure plate 42.

[0038] like Figure 3 As shown, in this embodiment, the second pressure plate 42 includes a second guide cylinder 421 and a second annular protrusion 422 connected to the edge of the second guide cylinder 421. The end of the guide post 22 passes through the second guide cylinder 421, and an anti-detachment structure 44 is disposed between the guide post 22 and the second guide cylinder 421. Specifically, a through hole is provided in the middle of the second guide cylinder 421, and the end of the guide post 22 passes through the through hole, thereby allowing the guide post 22 and the second guide cylinder 421 to move axially. The anti-detachment structure 44 includes a first protrusion disposed on the outer circumferential surface of the end of the guide post 22 and a second protrusion disposed on the inner circumferential surface of the second guide cylinder 421, with the first protrusion located inside the second protrusion. When the guide post 22 moves away from the second mounting cavity 60, and the first and second protrusions abut against each other, the guide post 22 can drive the second pressure plate 42 to move toward the first pressure plate 41.

[0039] like Figures 1 to 3As shown, in this embodiment, the elastic element 43 is a spring, which is sleeved outside the first guide cylinder 411 and the second guide cylinder 421, and the two ends of the spring abut against the first annular protrusion 412 and the second annular protrusion 422, respectively. Furthermore, the outer walls of the first guide cylinder 411 and the second guide cylinder 421 serve to position the spring, and the abutment of the first annular protrusion 412 and the second annular protrusion 422 compresses the spring, thereby buffering the movement of the valve core 20.

[0040] like Figure 4 As shown, in this embodiment, the connecting groove 21 includes a first end face 211 and a second end face 212 that are circumferentially opposite each other. The buffer groove 30 includes a first groove body 31 disposed on the first end face 211 and a second groove body 32 disposed on the second end face 212, with the first groove body 31 and the second groove body 32 disposed opposite each other. The first groove body 31 and the second groove body 32 can change the flow area, thereby reducing the problem of large flow rate changes caused by the stroke of the valve core 20.

[0041] like Figure 5 Preferably, the walls of the first groove 31 and the second groove 32 are both arc-shaped surfaces.

[0042] like Figure 4 and Figure 5 As shown, in this embodiment, the first groove 31 includes a first segment 311 and a second segment 312 connected to each other axially. The second segment 312 is located on the side of the first segment 311 facing away from the second groove 32. In the circumferential direction, the size of the second segment 312 is smaller than the size of the first segment 311. Specifically, the second segment 312 is disposed on the side of the first segment 311 facing away from the second groove 32. In the circumferential direction, the width of the second segment 312 is smaller than the width of the first segment 311. The first segment 311 and the second segment 312 are interconnected, and the first segment 311 has a semi-circular groove structure, while the second segment 312 has a long groove structure. Correspondingly, the second groove 32 has a semi-circular groove structure.

[0043] Based on the applicant's simulation experiment structure, the above-mentioned structural forms of the first tank 31 and the second tank 32 can achieve better buffering effect.

[0044] like Figure 6As shown, in this embodiment, there are multiple buffer grooves 30, which are spaced apart circumferentially. The first groove body 31 and the second groove body 32 of adjacent buffer grooves 30 are positioned opposite each other. Specifically, this embodiment has four buffer grooves 30, which are evenly spaced apart circumferentially. In adjacent buffer grooves 30, the first groove body 31 and the second groove body 32 are reversed; that is, in one buffer groove 30, the first groove body 31 is located on the first end face 211, and the second groove body 32 is located on the second end face 212; in another buffer groove 30, the first groove body 31 is located on the second end face 212, and the second groove body 32 is located on the first end face 211.

[0045] This embodiment also provides a piece of engineering machinery, including the aforementioned balance valve. Preferably, the balance valve is connected to the winch motor of the engineering machinery.

[0046] Based on the above description, the balancing valve of this embodiment has the following advantages:

[0047] 1. A single-sided spring design is adopted to reduce the impact of control pressure changes on the valve core stroke of the balance valve;

[0048] 2. The valve core is equipped with a circular arc step in the middle to change the flow area of ​​the valve core and reduce the problem of large flow rate changes caused by the valve core stroke;

[0049] 3. Throttling valves are used at both ends of the valve stem to achieve oil inlet damping, buffer the control pressure oil source pressure, and match the oil inlet damping and bypass damping to further buffer and control the control pressure.

[0050] 4. The entire structure has no pilot control, optimizes various flow channels and holes, and has a simple, compact, and reliable structure with excellent engineering value.

[0051] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A balancing valve, characterized in that, include: The valve body (10) is provided with a first oil port (11), and a second oil port (12) and a third oil port (13) located on both sides of the first oil port (11). A valve core (20) is movably disposed within the valve body (10). A connecting groove (21) is provided in the middle of the valve core (20). The connecting groove (21) is adapted to connect the first oil port (11) with the second oil port (12) or to connect the first oil port (11) with the third oil port (13). A buffer groove (30) is provided on the axial end face of the connecting groove (21). An elastic buffer structure (40) is disposed between one side of the valve core (20) and the valve body (10); The valve body (10) is provided with a first mounting cavity (50) and a second mounting cavity (60) that are interconnected. The valve core (20) is disposed in the first mounting cavity (50), and the elastic buffer structure (40) is disposed in the second mounting cavity (60). The elastic buffer structure (40) includes: The first pressure plate (41) is disposed on the side of the second mounting cavity (60) facing the first mounting cavity (50); The second pressure plate (42) is disposed on the side of the second mounting cavity (60) opposite to the first mounting cavity (50); An elastic element (43) is disposed between the first pressure plate (41) and the second pressure plate (42). Among them, the valve core (20) is provided with a guide post (22) at the end facing the second mounting cavity (60). The guide post (22) passes through the first pressure plate (41) and is connected to the second pressure plate (42). An anti-detachment structure (44) is provided between the guide post (22) and the second pressure plate (42). Both ends of the valve core (20) are provided with throttle valves, and the guide post (22) is connected to one of the throttle valves.

2. The balancing valve according to claim 1, characterized in that, The first pressure plate (41) includes a first guide cylinder (411) and a first annular protrusion (412) connected to the edge of the first guide cylinder (411). The guide post (22) passes through the first guide cylinder (411). The diameter of the first mounting cavity (50) is larger than the diameter of the second mounting cavity (60) so that a stepped surface (70) is formed between the first mounting cavity (50) and the second mounting cavity (60). The first annular protrusion (412) cooperates with the stepped surface (70).

3. The balancing valve according to claim 2, characterized in that, The second pressure plate (42) includes a second guide cylinder (421) and a second annular protrusion (422) connected to the edge of the second guide cylinder (421). The end of the guide post (22) passes through the second guide cylinder (421), and the anti-detachment structure (44) is disposed between the guide post (22) and the second guide cylinder (421).

4. The balancing valve according to claim 3, characterized in that, The elastic element (43) is a spring, which is sleeved outside the first guide cylinder (411) and the second guide cylinder (421), and the two ends of the spring abut against the first annular protrusion (412) and the second annular protrusion (422) respectively.

5. The balancing valve according to any one of claims 1 to 4, characterized in that, The connecting groove (21) includes a first end face (211) and a second end face (212) that are circumferentially opposite each other. The buffer groove (30) includes a first groove body (31) and a second groove body (32). The first groove body (31) is disposed on one of the first end face (211) and the second end face (212), and the second groove body (32) is disposed on the other of the first end face (211) and the second end face (212). The first groove body (31) and the second groove body (32) are disposed opposite each other.

6. The balancing valve according to claim 5, characterized in that, The walls of the first groove (31) and the second groove (32) are arc-shaped.

7. The balancing valve according to claim 5, characterized in that, The first groove (31) includes a first segment (311) and a second segment (312) that are connected to each other along the axial direction. The second segment (312) is located on the side of the first segment (311) away from the second groove (32). In the circumferential direction, the size of the second segment (312) is smaller than the size of the first segment (311).

8. The balancing valve according to claim 7, characterized in that, There are multiple buffer slots (30), and the multiple buffer slots (30) are arranged at intervals along the circumference. The first slot body (31) and the second slot body (32) of adjacent buffer slots (30) are arranged in opposite positions.

9. An engineering machinery, characterized in that, Includes the balance valve as described in any one of claims 1 to 8.

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