Load-sensitive multi-way valve

Abstract

The invention provides a load-sensitive multi-way valve, and belongs to the technical field of multi-way valves. The problem that oil inlet flow output of an existing hydraulic system cannot be adjusted in real time under the condition of high load is solved. The load-sensitive multi-way valve comprises a valve body, the valve body comprises an oil inlet unit and at least one reversing unit, and the oil inlet unit is provided with a main oil return way, a main oil way communicated with an external variable pump and a main feedback oil way. The reversing unit is provided with a reversing oil inlet oil way communicated with the main oil way, a reversing load pressure Ls oil way communicated with the main feedback oil way and a reversing oil return oil way communicated with the main oil return oil way, the oil inlet unit is further provided with an auxiliary oil way communicated with an external metering pump, and an unloading diverter valve capable of being communicated with the auxiliary oil way and the main oil return oil way is arranged in the oil inlet unit. A flow dividing unloading valve element capable of adjusting the flow during movement is arranged in the unloading flow dividing valve. The load-sensitive multi-way valve can adjust the ratio of the oil quantity of the auxiliary oil way entering the main oil way to the oil quantity of the main oil return way, and the oil quantity supply of the reversing oil inlet way can be adjusted in real time.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of multi-way valves, and relates to a load-sensitive multi-way valve. BACKGROUND

[0002] The loader is an engineering machinery with high work efficiency and wide application, and a hydraulic system of the loader mainly comprises a working hydraulic system and a steering hydraulic system. The load sensing technology in the field of hydraulic transmission is applied to the hydraulic system of the engineering machinery, can control one or more execution elements to work, and has very good fine adjustment performance. Under the premise of meeting various control functions of the machine, the load sensing technology reduces pressure loss, improves efficiency, and has better economy, reliability and advancement. For the pump control or valve control hydraulic system, the application of the load sensing technology can effectively improve the system work efficiency.

[0003] The existing load-sensitive multi-way valve, such as the electric control load-sensitive multi-way valve disclosed in Chinese Patent Application

Grant Announcement No. CN220566338U

[0004] The oil pressure required by each load-sensitive three-way directional valve in the main oil path system in the above structure changes with work, and the oil supply needs to be adjusted and controlled, wherein the three-way flow valve is unloaded by opening the valve port through pressure comparison, when the fixed displacement pump system is used in the multi-way valve, the P port has a certain pressure loss when the multi-way valve is not working, which is generally 1.4 MPa, the flow of the pump is greater than the load demand, and the three-way flow valve is unloaded, at this time, the high-pressure unloading excess flow is the same as the load pressure, when the cylinder reaches the limit position, the system does not need flow, and all the flow is unloaded through the three-way flow valve, in addition, the oil inlet valve body is provided with a supplementary oil inlet connected with the total oil inlet P, but it can only passively increase the oil supply, and cannot dynamically change the oil supply according to the required oil pressure of each load-sensitive three-way directional valve, cannot actively regulate the flow according to the system pressure change, causes a large amount of energy waste in the system, excess flow, and causes energy waste in the system. SUMMARY

[0005] The purpose of the present application is to solve the above-mentioned problems existing in the prior art, and to provide a load-sensitive multi-way valve.

[0006] The purpose of the present application can be realized by the following technical scheme:

[0007] A load-sensitive multi-way valve, comprising a valve body, the valve body comprising an oil inlet association and at least one reversing association, the oil inlet association having a main oil return oil path, a main oil path communicated with an external variable pump and a main feedback oil path, the reversing association having a reversing oil inlet oil path communicated with the main oil path, a reversing load pressure Ls oil path communicated with the main feedback oil path and a reversing oil return oil path communicated with the main oil return oil path, characterized in that the oil inlet association further comprises an auxiliary oil path communicated with the external fixed displacement pump, the oil inlet association is provided with an unloading flow dividing valve capable of communicating the auxiliary oil path and the main oil return oil path, the unloading flow dividing valve is provided with a flow dividing unloading valve core capable of adjusting the flow when moving, the unloading flow dividing valve has a control cavity and a spring cavity located at both ends of the unloading flow dividing valve, the main oil path is communicated with the control cavity, the main feedback oil path is communicated with the spring cavity, and the spring cavity is provided with a compression spring acting on one end of the flow dividing unloading valve core, and the oil inlet association is further provided with a confluence check valve capable of guiding the auxiliary oil path to the main oil path, when the pressure difference between the main oil path and the main feedback oil path is greater than or equal to the set value of the compression spring, the auxiliary oil path and the main oil return oil path are communicated.

[0008] When the multi-way valve is micro-controlled or the feedback pressure of the main feedback oil path is 0, the pressure difference between the oil pressure of the main oil path and the oil pressure of the main feedback oil path is greater than or equal to the total initial pressure of the compression spring, the oil pressure of the main oil path pushes the shunt unloading valve core to move right (here, the left and right directions are relative), so that the oil in the auxiliary oil path flows back to the main return oil path, and at the same time, the combined one-way valve remains closed, only relying on the oil of the variable pump to realize oil supply to the reversing oil inlet path of the reversing joint, so that the mechanical assembly connected to the reversing joint can make corresponding operation action, and the auxiliary oil path unloads back to the main return oil path at a lower pressure; when the multi-way valve is working at a large opening, the oil pressure of the main feedback oil path increases, the pressure difference between the oil pressure of the main oil path and the oil pressure of the main feedback oil path is less than the compression spring pressure, the oil pressure of the main feedback oil path and the compression spring pressure push the shunt unloading valve core to move left, the oil amount of the auxiliary oil path flowing into the main return oil path gradually decreases, and the oil in the auxiliary oil path increases rapidly with the continuous injection of the oil of the constant pump, and when the oil pressure increases to a value that can push the combined one-way valve open, the auxiliary oil path is connected to the main oil path, and the oil in the auxiliary oil path flows into the main oil path, combining the oil of the constant pump and the variable pump, and after the combination, oil supply is realized to the reversing oil inlet path of the reversing joint, and the oil pressure of the reversing load pressure Ls oil path change can be realized according to the different working conditions of the mechanical assembly under high load, and the main feedback oil path directly acts the oil pressure of the reversing load pressure Ls oil path change on one end of the shunt unloading valve core, and cooperates with the elastic force of the compression spring to realize the real-time movement of the shunt unloading valve core between the continuously changing oil pressures, thereby adjusting the oil amount ratio of the auxiliary oil path entering the main oil path and the main return oil path, and realizing real-time adjustment of the oil supply of the reversing oil inlet path.

[0009] Through the above-mentioned shunt unloading valve core, main oil path, auxiliary oil path, main return oil path, main feedback oil path and compression spring, the oil of the constant pump can be combined into the main oil path of the variable pump through the auxiliary oil path under high load, the main oil path is communicated with the reversing oil inlet path of the reversing joint, the large oil amount is supplied, and the oil supply amount is adjusted in real time through the change of the oil pressure during the supply, the real-time oil supply amount adjustment under high load is realized, when the normal work or the multi-way valve is not operated, the oil in the auxiliary oil path can be directly unloaded back to the main return oil path at a low pressure, without affecting the normal oil supply of the variable pump, ensuring the normal oil supply accuracy of the variable pump, and the combination of the constant pump and the variable pump can reduce the equipment cost.

[0010] In the above-mentioned load-sensitive multi-way valve, a control oil channel is arranged on the oil inlet joint along the axial direction of the unloading shunt valve, the main oil path is communicated with the control cavity through the control oil channel, and a damping plug one is arranged in the control oil channel.

[0011] The control oil channel is arranged in the axial direction, the main oil passage is communicated with the left end port of the unloading shunt valve through the control oil channel, the damping plug is arranged to reduce the flow speed of the oil, avoid the oil entering the small area cavity to generate a large impact, and avoid the oil impacting the shunt unloading valve core to play a buffering role.

[0012] In the load-sensitive multi-way valve, the middle part of the shunt unloading valve core is located in the auxiliary oil passage, and the end is provided with an annular throttling groove.

[0013] The throttling groove is arranged in the middle part of the shunt unloading valve core, so that the structure of the hydraulic elements in the valve body is compact, and the oil flow path is shortened.

[0014] In the load-sensitive multi-way valve, the throttling groove is provided with a pilot flow groove extending to the outer peripheral wall on the groove wall close to the spring cavity, and the pilot flow groove is arc-shaped and arranged on the side towards the spring cavity.

[0015] When the shunt unloading valve core moves, the oil in the auxiliary oil passage flows out through the pilot flow groove first. Since the size of the pilot flow groove is small, only a small part of the oil flows out at the beginning of the movement of the shunt unloading valve core. With the continuous movement of the unloading valve core, the oil flows out in large amount through the throttling groove. The combination of the pilot flow groove and the throttling groove realizes timing control of pressure relief, so that the shunt unloading valve core moves stably, and the closing process of the confluence check valve is stable, thereby further improving the output accuracy of the oil inlet flow.

[0016] In the load-sensitive multi-way valve, the Ls overflow valve is arranged in the main feedback oil passage, and the main feedback oil passage can be communicated with the main return oil passage through the Ls overflow valve.

[0017] A certain threshold value is set in the Ls overflow valve. When the oil pressure of the main feedback oil passage exceeds the threshold value, the oil in the main feedback oil passage flows into the main return oil passage through the Ls overflow valve, thereby improving the stability of the oil in the main feedback oil passage flowing into the spring cavity.

[0018] In the load-sensitive multi-way valve, the unloading shunt valve and the Ls overflow valve are located on one side of the oil inlet link, and the main safety valve capable of communicating the main oil passage and the main return oil passage is arranged on the other side of the oil inlet link.

[0019] The arrangement of the above structure makes the overall layout of the oil inlet link better, and the structure of the valve body is compact.

[0020] In the load-sensitive multi-way valve, the main feedback oil passage includes an oil channel one communicated with the reversing load pressure Ls oil passage, an oil channel three communicated with the spring cavity, and an oil channel two arranged between the oil channel one and the oil channel three, and the oil channel two communicates the oil channel one and the oil channel three.

[0021] Through the setting of the oil passage one, the oil passage two and the oil passage three, the flow of the oil is smoother, and the processing of the oil passage one, the oil passage two and the oil passage three is facilitated.

[0022] In the load-sensitive multi-way valve, the oil passage one is provided with a damping plug two, the oil passage three is provided with a damping hole, and the damping hole is provided with a damping plug three.

[0023] The damping plug two and the damping plug three are used to further reduce the flow speed of the oil, avoid the oil entering the small area cavity to generate a large impact, and avoid the oil impacting the shunt unloading valve core, thereby playing a buffering role.

[0024] In the load-sensitive multi-way valve, the upper end of the oil passage three extends upward and penetrates the valve body, the oil inlet joint is provided with a plug at the upper end port of the oil passage three, and the Ls overflow valve is arranged at the middle part of the oil passage three.

[0025] When the oil pressure of the main feedback oil way accumulates enough, the Ls overflow valve is opened, the oil pressure generates a large impact force, the upper end of the oil passage three penetrates the valve body, so that the oil of the main feedback oil way can be buffered at the opening moment, and the processing and forming of the oil passage three are facilitated.

[0026] Compared with the prior art, the load-sensitive multi-way valve has the following advantages:

[0027] 1. Through the setting of the shunt unloading valve core, the main oil way, the auxiliary oil way, the main return oil way, the main feedback oil way and the compression spring, the oil of the constant delivery pump can be merged into the main oil way of the variable pump through the auxiliary oil way under high load, the large oil supply is realized through the communication of the main oil way and the reversing oil inlet oil way of the reversing joint, the oil supply amount is adjusted in real time through the change of the oil pressure during the supply, the real-time oil supply amount adjustment under high load is realized, when the multi-way valve is not operated or normally operated, the oil in the auxiliary oil way can be directly unloaded to the main return oil way at low pressure, the normal oil supply of the variable pump is not affected, the normal oil supply precision of the variable pump is ensured, and the combination of the constant delivery pump and the variable pump can reduce the equipment cost.

[0028] 2. A certain threshold value is set in the Ls overflow valve, when the oil pressure of the main feedback oil way exceeds the threshold value, the oil of the main feedback oil way flows into the main return oil way through the Ls overflow valve, and the stability of the oil flowing into the spring cavity from the main feedback oil way is improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is the hydraulic principle diagram of the application.

[0030] Figure 2This is a hydraulic schematic diagram of the oil inlet connection in this invention.

[0031] Figure 3 This is a schematic diagram of the structure of the present invention.

[0032] Figure 4 This is a schematic diagram of the oil inlet assembly in this invention.

[0033] Figure 5 It is along Figure 4 Partial sectional view of AA.

[0034] Figure 6 yes Figure 5 A magnified view of a portion of point A in the middle.

[0035] Figure 7 This is a partial cross-sectional view of the commutator in this invention.

[0036] In the diagram, 1. Oil inlet; 11. Main oil circuit; 12. Main return oil circuit; 13. Main feedback oil circuit; 13a. Oil passage one; 13b. Oil passage two; 13c. Oil passage three; 13c1. Damping orifice; 14. Unloading diverter valve; 14a. Diverter unloading valve core; 14b. Control chamber; 14c. Spring chamber; 14d. Throttling groove; 14e. Pilot flow groove; 15. Auxiliary oil circuit; 16. Control oil circuit; 2. Reversing connection; 21. Reversing inlet oil circuit; 22. Reversing return oil circuit; 23. Reversing load pressure feedback Ls oil circuit; 3. Valve body; 4. Compression spring; 5. Converging check valve; 6. Damping plug one; 7. Ls relief valve; 8. Damping plug two; 9. Damping plug three; 10. Blockage; 101. Main safety valve. Detailed Implementation

[0037] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0038] like Figures 1-5 As shown, this load-sensitive multi-way valve includes a valve body 3. The valve body 3 includes an inlet line 11 and at least one reversing line 22. The inlet line 1 has a main return oil passage 12, a main oil passage 11 connected to an external variable pump, and a main feedback oil passage 13. The reversing line 2 has a reversing inlet oil passage 21 connected to the main oil passage 11, a reversing load pressure Ls oil passage 23 connected to the main feedback oil passage 13, and a reversing return oil passage 22 connected to the main return oil passage 12.

[0039] Furthermore, such as Figures 1-5As shown, the oil inlet unit 1 also has an auxiliary oil passage 15 in communication with the external constant pump, and the oil inlet unit 1 is provided with an unloading shunt valve 14 capable of communicating the auxiliary oil passage 15 and the main oil return passage 12, and the unloading shunt valve 14 is provided with a shunt unloading valve core 14a capable of adjusting the flow when moving, the unloading shunt valve 14 has a control cavity 14b and a spring cavity 14c located at both ends of the unloading shunt valve 14 respectively, the main oil passage 11 is in communication with the control cavity 14b, the main feedback oil passage 13 is in communication with the spring cavity 14c, and the spring cavity 14c is provided with a compression spring 4 acting on one end of the shunt unloading valve core 14a, and the oil inlet unit 1 is also provided with a confluence check valve 5 capable of guiding the auxiliary oil passage 15 to the main oil passage 11, when the pressure difference between the main oil passage 11 and the main feedback oil passage 13 is greater than or equal to the set value of the compression spring 4, the auxiliary oil passage 15 and the main oil return passage 12 are communicated.

[0040] When the multi-way valve micro-control operation or the multi-way valve does not operate the main feedback oil passage 13 feedback pressure is 0, the pressure difference between the oil pressure of the main oil passage 11 and the oil pressure of the main feedback oil passage 13 is greater than or equal to the initial pressure of the compression spring 4, the oil pressure of the main oil passage 11 drives the shunt unloading valve core 14a to move to the right, here the left and right directions are relative, so that the oil in the auxiliary oil passage 15 flows back to the main oil return passage 12, at the same time the confluence check valve 5 remains closed, only relying on the oil of the variable pump to realize the oil supply to the reversing oil inlet oil passage 21 of the reversing unit 2, so that the mechanical components connected to the reversing unit 2 can make corresponding operation actions, the auxiliary oil passage 15 unloads back to the main oil return passage 12 at a lower pressure; when the multi-way valve is working at a large opening, the oil pressure of the main feedback oil passage 13 increases, the pressure difference between the oil pressure of the main oil passage 11 and the oil pressure of the main feedback oil passage 13 is less than the pressure of the compression spring 4, the oil pressure of the main feedback oil passage 13 and the pressure of the compression spring 4 drive the shunt unloading valve core 14a to move to the left, the oil amount of the auxiliary oil passage 15 flowing into the main oil return passage 12 gradually decreases, the oil in the auxiliary oil passage 15 increases rapidly with the continuous injection of the oil of the constant pump, and when the oil pressure increases to the pressure capable of pushing away the confluence check valve 5, the confluence of the auxiliary oil passage 15 to the main oil passage 11 is realized, the oil in the auxiliary oil passage 15 flows into the main oil passage 11, and the oil of the constant pump and the variable pump is combined, after the combination, the oil supply to the reversing oil inlet oil passage 21 of the reversing unit 2 is realized, and the reversing load pressure Ls oil passage 23 change oil pressure fed back by multiple mechanical components under high load conditions of the reversing unit 2 can also be realized, and the main feedback oil passage 13 directly acts the reversing load pressure Ls oil passage 23 change oil pressure on one end of the shunt unloading valve core 14a, cooperates with the elastic force of the compression spring 4, realizes the real-time movement of the shunt unloading valve core 14a between the continuously changing oil pressures, and further can adjust the oil amount ratio of the auxiliary oil passage 15 entering the main oil passage 11 and the main oil return passage 12, and realizes the real-time adjustment of the oil amount supply of the reversing oil inlet oil passage 21.

[0041] Through the setting of the shunt unloading valve core 14a, the main oil path 11, the auxiliary oil path 15, the main return oil path 12, the main feedback oil path 13 and the compression spring 4, in the case of high load, the oil of the constant delivery pump can be combined through the auxiliary oil path 15 into the main oil path 11 of the variable pump, the main oil path 11 is communicated with the reversing oil inlet path 21 of the reversing connection 2, the large oil amount is supplied, and in the process of supply, the oil supply amount is adjusted in real time through the change of oil pressure, the real-time oil supply amount adjustment in the case of high load is realized, when normal work or the multi-way valve is not operated, the oil in the auxiliary oil path 15 can be directly unloaded to the main return oil path 12 at low pressure, the normal oil supply of the variable pump is not affected, the normal oil supply precision of the variable pump is ensured, and the combination of the constant delivery pump and the variable pump can reduce the equipment cost.

[0042] As shown in Figure 5 , the control oil channel 16 is arranged along the axial direction of the shunt unloading valve core 14a, the main oil path 11 is communicated with the control cavity 14b through the control oil channel 16, and the damping plug one 6 is arranged in the control oil channel 16.

[0043] As shown in Figure 5 and Figure 6 , the middle part of the shunt unloading valve core 14a is located in the auxiliary oil path 15, the throttling groove 14d in the annular shape is arranged at the end, the oil inlet of the combination one-way valve 5 is communicated with the auxiliary oil path 15, the pilot flow groove 14e is arranged on the groove wall of the side close to the spring cavity 14c and extends to the outer peripheral wall, the pilot flow groove 14e is in the arc shape and is arranged along the side towards the spring cavity 14c.

[0044] As shown in Figures 5-7 , the Ls overflow valve 7 is arranged in the main feedback oil path 13, the main feedback oil path 13 can be communicated with the main return oil path 12 through the Ls overflow valve 7, the unloading shunt valve 14 and the Ls overflow valve 7 are located on one side of the oil inlet connection 1, the main safety valve 101 capable of communicating the main oil path 11 with the main return oil path 12 is arranged on the other side of the oil inlet connection 1, the main feedback oil path 13 includes the oil channel one 13a communicated with the reversing load pressure Ls oil path 23, the oil channel three 13c communicated with the spring cavity 14c and the oil channel two 13b arranged between the oil channel one 13a and the oil channel three 13c, the oil channel two 13b communicates the oil channel one 13a and the oil channel three 13c, the damping plug two 8 is arranged in the oil channel one 13a, the damping hole 13c 1 is arranged in the oil channel three 13c, the damping plug three 9 is arranged in the damping hole 13c 1, the upper end of the oil channel three 13c extends upwards and penetrates through the valve body 3, the plug 10 is arranged at the oil channel three 13c end port of the oil inlet connection 1, and the Ls overflow valve 7 is arranged at the middle part of the oil channel three 13c.

[0045] The specific embodiments described herein are merely illustrative of the spirit of the application. Various modifications or changes in the specific embodiments described herein can occur to those skilled in the art to which the application pertains without departing from the spirit of the application, and it is understood that such modifications or changes are to be considered as within the scope of the application as defined by the appended claims.

Claims

1. A load sensitive multi-way valve comprising a valve body (3) including an oil inlet link (1) and at least one reversing link (2), said oil inlet link (1) having a main oil return oil passage (12), a main oil passage (11) communicating with an external variable pump, and a main feedback oil passage (13), said reversing link (2) having a reversing oil inlet oil passage (21) communicating with the main oil passage (11), a reversing load pressure Ls oil passage (23) communicating with the main feedback oil passage (13), and a reversing oil return oil passage (22) communicating with the main oil return oil passage (12), characterized in that, The oil inlet joint (1) also has an auxiliary oil path (15) in communication with the external metering pump, the oil inlet joint (1) is provided with an unloading shunt valve (14) capable of communicating the auxiliary oil path (15) and the main oil return path (12), the unloading shunt valve (14) is provided with a shunt unloading valve core (14a) capable of adjusting flow when moving, the unloading shunt valve (14) has a control cavity (14b) and a spring cavity (14c) located at both ends of the unloading shunt valve (14) respectively, the main oil path (11) is in communication with the control cavity (14b), the main feedback oil path (13) is in communication with the spring cavity (14c), and the spring cavity (14c) is provided with a compression spring (4) acting on one end of the shunt unloading valve core (14a), the oil inlet joint (1) is also provided with a confluence check valve (5) capable of guiding the auxiliary oil path (15) to the main oil path (11), when the pressure difference between the main oil path (11) and the main feedback oil path (13) is greater than or equal to the set value of the compression spring (4), the auxiliary oil path (15) and the main oil return path (12) are in communication.

2. The load sensing multiple spool valve of claim 1, wherein, The oil inlet joint (1) is provided with a control oil channel (16) arranged along the axial direction of the shunt unloading valve core (14a), the main oil path (11) is in communication with the control cavity (14b) through the control oil channel (16), and the control oil channel (16) is provided with a damping plug one (6).

3. The load sensing multiple spool valve of claim 2 wherein, The middle part of the shunt unloading valve core (14a) is located in the auxiliary oil path (15), and the end is provided with an annular throttle groove (14d), and the oil inlet of the confluence check valve (5) is in communication with the auxiliary oil path (15).

4. The load sensing multiple spool valve of claim 1 or 2 or 3, wherein, The throttle groove (14d) is provided with a pilot flow groove (14e) extending to the outer peripheral wall on the groove wall near the spring cavity (14c), and the pilot flow groove (14e) is arc-shaped and is arranged on the side facing the spring cavity (14c).

5. The load sensing multiple spool valve of claim 1 or 2 or 3, wherein, The main feedback oil path (13) is provided with an Ls overflow valve (7), and the main feedback oil path (13) can be in communication with the main oil return path (12) through the Ls overflow valve (7).

6. The load sensing multiple spool valve of claim 5, wherein, The unloading shunt valve (14) and the Ls overflow valve (7) are located on one side of the oil inlet joint (1), and the other side of the oil inlet joint (1) is provided with a main safety valve (101) capable of communicating the main oil path (11) and the main oil return path (12).

7. The load sensing multiple spool valve of claim 6 wherein, The main feedback oil path (13) includes an oil channel one (13a) in communication with a reversing load pressure Ls oil path (23), an oil channel three (13c) in communication with the spring cavity (14c), and an oil channel two (13b) arranged between the oil channel one (13a) and the oil channel three (13c), and the oil channel two (13b) communicates the oil channel one (13a) and the oil channel three (13c).

8. The load sensing multiple spool valve of claim 6, wherein, The oil channel one (13a) is provided with a damping plug two (8), the oil channel three (13c) is provided with a damping hole (13c1), and the damping hole (13c1) is provided with a damping plug three (9).

9. The load sensing multiple spool valve of claim 6, wherein, The upper end of the oil channel three (13c) extends upward and penetrates the valve body (3), the oil inlet joint (1) is provided with a plug (10) at the upper end port of the oil channel three (13c), and the Ls overflow valve (7) is arranged in the middle part of the oil channel three (13c).

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