Anti-impact low-hysteresis integrated multi-way valve and control method thereof

Abstract

The invention relates to an anti-impact low-hysteresis integrated multi-way valve and a control method thereof, a valve body of the multi-way valve is integrally cast, is universal for manual and hydraulic control, is integrated with a rotary brake release valve, and is used for providing pressure for brake release of a rotary motor during manual control; the integrated dangerous working condition unloading valve is used for overload pressure unloading during manual control; the standby low-pressure unloading valve is integrated and used for low-pressure unloading during standby, unloading noise is low, and energy is saved; the integrated telescopic switching valve is used for switching of telescopic oil cylinder control during hydraulic control. System pipeline connection is simplified by integrating the valves. After-valve compensation is adopted, LS pressure acts on a compensator spring cavity through damping and a one-way valve, the compensator is opened slowly and closed quickly, load sensitive response rapidness is guaranteed, and the stability of the compensator during composite action is achieved. The three-way pressure compensator adopts a double-spring design, so that the diverter valve can be quickly opened, and the influence of the three-way pressure compensator on hysteresis of main and auxiliary coiling, amplitude variation and telescopic work is reduced.

Description

Technical Field

[0001] The invention patent relates to the field of hydraulic valves, and in particular to an anti-shock low-hysteresis integrated multi-way valve and a control method thereof. Background Art

[0002] The multi-way valve is a key component of the hydraulic system of construction machinery. It is located between the power source and the actuator and is used to control the direction and flow of the hydraulic oil, thereby centrally controlling the movement direction and speed of the construction machinery actuator. The performance of the multi-way valve directly affects the operability and comfort of the entire system.

[0003] In order to improve the operating characteristics of the multi-way valve, a load-sensitive multi-way valve has been developed. A compensator is arranged in the load-sensitive multi-way valve. By keeping the pressure difference before and after the valve stem throttle port basically constant, the output flow is only related to the valve stem opening and has nothing to do with the load, thereby improving the operational coordination during compound actions. However, small impact and fast response cannot be met at the same time, and there is a large hysteresis problem when used in a quantitative pump system.

[0004] The existing crane multi-way valves are divided into integral multi-way valves and plate multi-way valves. The integral multi-way valve usually only integrates the winch, luffing, telescopic and slewing working links. The telescopic switching valve, slewing brake release valve, dangerous working condition unloading valve, etc. in the load-sensitive system of the quantitative pump on the car are arranged in a dispersed manner using functional valve blocks, and the quantitative pump flow is unloaded through the three-way pressure compensator when in standby mode. The compensator in the multi-way valve adopts fixed damping buffer.

[0005] The telescopic switching valve, swing brake release valve, hazardous condition unloading valve and other functions in the on-board metering pump load-sensitive system adopt functional valve blocks, which are arranged in a dispersed manner, with complex pipeline connections, high costs, and many leakage points and failure points; when the metering pump load-sensitive system is on standby, the pump flow is unloaded through the three-way pressure compensator, which is noisy and energy-intensive; the working hysteresis loop of the metering pump load-sensitive system is affected by the three-way pressure compensator, and the hysteresis loop is large; the multi-way valve compensator adopts fixed damping buffering, which has a slow response. Summary of the invention

[0006] The object of the present invention is to overcome the deficiencies in the prior art and to provide an anti-shock low-hysteresis integrated multi-way valve and a control method thereof.

[0007] In order to solve the problems of the prior art, the present invention discloses an anti-impact low-hysteresis integrated multi-way valve, the valve body of the multi-way valve is integrally cast, and is provided with a D port, a T1 port, an L port, a K port, a LS port, a P1 port, a P2 port, a T1 port and a T2 port, and also includes a first joint, a working joint and a rotary valve; the first joint includes: a rotary brake release valve, a dangerous working condition unloading valve, a standby low-pressure unloading valve, a three-way pressure compensator, a telescopic switching valve, a safety valve, a first damping, a second damping and a first check valve; a power source quantitative pump is connected to the P1 port to provide a constant flow for the multi-way valve, and the P1 port is connected to the three-way pressure compensator, The telescopic switching valve, the safety valve and the working connection are connected; the T1 port is connected to the standby low-pressure unloading valve, the three-way pressure compensator, the safety valve and the working connection; the LS port is connected to the dangerous condition unloading valve, the three-way pressure compensator and the working connection, and the LS port is connected to the T1 port through the second damper and the first damper; the L port is connected to the swing brake release valve, the dangerous condition unloading valve and the telescopic switching valve; the K port is connected to the swing brake release valve; the D port is connected to the telescopic switching valve; the dangerous condition unloading valve is connected to the standby low-pressure unloading valve; the swing brake release valve is connected to the working connection, and the P2 port is connected to the swing brake release valve through the first check valve.

[0008] Furthermore, the working connection includes several connections, each connection is provided with a pilot oil port and a working oil port, and each connection includes a main valve core, a compensator and a second one-way valve; the main valve core is respectively connected to the pilot oil port and the working oil port, the compensator is connected to the main valve core, and the compensator is connected to the rotary brake release valve through the second one-way valve.

[0009] Furthermore, the P1 port is connected to the a port of the three-way pressure compensator, the a port of the telescopic switching valve, one end of the safety valve and the P port of the main valve core; the T1 port is connected to the b port of the standby low-pressure unloading valve, the b port of the three-way pressure compensator, the other end of the safety valve and the T port of the main valve core; the LS port is connected to the c port of the dangerous working condition unloading valve, the spring chamber of the three-way pressure compensator and the b port of the compensator, and the LS port is connected to the T1 port through the second damping and the first damping; the L port is connected to the a port of the slewing brake release valve, the a port of the dangerous working condition unloading valve and the telescopic switching valve The b port of the main valve core is connected to the b port of the compensator; the K port is connected to the c port of the swing brake release valve; the D port is connected to the c port of the telescopic switching valve; the b port of the dangerous condition unloading valve is connected to the spring chamber of the standby low-pressure unloading valve; the P' port of the main valve core is connected to the a port of the compensator and is connected to the b port of the swing brake release valve through the second one-way valve, the P" port of the main valve core is connected to the c port of the compensator, and the A and B ports of the main valve core are connected to the working oil port; the P2 port is connected to the b port of the swing brake release valve through the first one-way valve, and the pilot oil port is connected to the pilot handle oil port that controls the action of the main valve core.

[0010] Furthermore, the standby low-pressure unloading valve includes a cone valve, a standby low-pressure unloading valve spring and a plug. The cone valve is provided with a right chamber and a spring chamber. The pressure at the P1 port acts on the right chamber, and the LS pressure acts on the spring chamber through the dangerous working condition unloading valve. The plug is used to limit the stroke of the cone valve.

[0011] Furthermore, the three-way pressure compensator includes a left screw plug, a first spring, a three-way pressure compensator valve core, a second spring and a right screw plug. The first spring is located at the left end, and the LS pressure acts on the first spring chamber. The second spring is located at the right end, and the P1 port pressure acts on the second spring chamber. The left screw plug and the right screw plug are used to limit the stroke of the three-way pressure compensator valve core. The compression amount of the second spring is the covering amount of the three-way pressure compensator valve core. From the connection between P1 port and T port to the full opening of P1-T, the equivalent pressure of the first spring and the second spring is a constant. When the P1 port-LS pressure is greater than the equivalent pressure of the first spring and the second spring, the three-way pressure compensator opens.

[0012] Furthermore, the compensator includes a screw plug, a compensator spring, a third one-way valve, a groove damping, a third damping and a compensator valve core. The P' port pressure acts on the lower end of the compensator valve core, and the LS pressure acts on the compensator spring chamber through the third one-way valve, the third damping and the groove damping. When the compensator valve core reaches a balanced state under the compensator spring, the LS pressure and the P' port pressure, the P' port pressure is almost equal to the LS pressure; the screw plug limits the stroke of the compensator valve core.

[0013] Correspondingly, in the control method of the above-mentioned anti-shock low-hysteresis integrated multi-way valve, when the pilot handle is not operated, there is no pressure in the pilot oil port, the main valve core is in the middle position, the P' port pressure of the main valve core is zero, the compensator valve core does not move, the LS pressure is close to zero, the standby low-pressure unloading valve is opened, and the oil from the metering pump returns to the T1 port from the standby low-pressure unloading valve.

[0014] Correspondingly, in the control method of the above-mentioned impact-proof low-hysteresis integrated multi-way valve, when a single link in the working link needs to be activated, the pilot handle of the single link is pushed, the pressure of the pilot oil port increases, the main valve core is reversed, the throttle port from port P to port P' increases to fully open, port P is connected to port P', pressure is established at port P', the compensator moves upward under the pressure of port P', port a of the compensator is connected to port c, and at the same time connected to port A or port B of the main valve core, and port a of the compensator is connected to port b, the pressure of port P' is fed back to port LS, and the LS pressure acts on the compensator spring chamber through the third one-way valve, the third damping and the groove damping; the standby low-pressure unloading valve is closed, the three-way pressure compensator is opened, part of the flow of the quantitative pump flows through the working link to the working oil port, and part flows through the three-way pressure compensator back to port T1.

[0015] Correspondingly, in the control method of the above-mentioned anti-shock low-hysteresis integrated multi-way valve, when two links in the working link need to perform a compound action, the pilot handles of the two links are pushed, the main valve cores of the two links are switched, the throttle port from the P port to the P' port is increased to fully open, and the P port is connected to the P' port. Pressure is established at the P' port, and the compensator moves upward under the pressure of the P' port. The a port of the compensator is connected to the c port, and is also connected to the A port or the B port of the main valve core. The working oil port pressure of the one with the larger load pressure in the two connections is fed back to the a port of the compensator through the c port of the compensator, so that the compensator of this connection moves upward, and the a port of the compensator of this connection is connected to the b port. The larger load pressure of this connection is fed back to the LS port, and the LS pressure acts on the spring chamber of the compensator of the two connections through the third one-way valve, the third damping and the groove damping. At this time, the a port and the b port of the compensator of the one with the smaller load are not connected, and the P' port pressure of this connection is almost equal to the LS pressure and the P' port of the larger load connection. Therefore, the pressure difference before and after the throttle port of the main throttle valve core of the two connections is equal, and the flow distribution through the two connections is only related to the size of the throttle port of the two connections, and has nothing to do with the load.

[0016] Correspondingly, in the control method of the above-mentioned anti-shock low-hysteresis integrated multi-way valve, when the multi-way valve is manually controlled, port K provides pressure for the swing brake release valve; when the swing brake release valve is not energized, port c of the swing brake release valve is connected to port a, that is, port K is connected to port L, and the swing brake release pressure is zero; when the swing brake release valve is energized, port c of the swing brake release valve is connected to port b, that is, port K is connected to port b of the swing brake release valve, when there is pressure at port P2, port P2 acts on port b of the swing brake release valve through the first one-way valve, and port K is the pressure of port P2, thereby realizing the release of the swing brake; or when there is pressure at port P' of the main valve core, the pressure at port P' acts on port b of the swing brake release valve through the second one-way valve, and port K is the pressure of port P', thereby realizing the release of the swing brake; When the hazardous condition unloading valve is not energized, port c of the hazardous condition unloading valve is connected to port b, that is, LS pressure acts on the spring chamber of the standby low-pressure unloading valve, and LS pressure is not unloaded; when the hazardous condition unloading valve is energized, port c of the hazardous condition unloading valve is connected to port a, that is, LS pressure is unloaded to port L through the hazardous condition unloading valve, thereby realizing the unloading of system pressure under hazardous conditions.

[0017] The present invention has the beneficial effects: (1) The present invention relates to an impact-proof, low-hysteresis integrated multi-way valve, the valve body of which is integrally cast and integrates the main and auxiliary rolls, variable amplitude, telescopic working joints and rotary valves. It is universal for manual and hydraulic control, making the product easy to process, efficient, with low leakage risk and high reliability.

[0018] (2) The multi-way valve of the present invention is integrated with a swing brake release valve, which is used to provide pressure for releasing the brake of the swing motor during manual control.

[0019] (3) The multi-way valve of the present invention is integrated with a hazardous condition unloading valve, which is used to unload overload pressure during manual control.

[0020] (4) The multi-way valve of the present invention integrates a standby low-pressure unloading valve, which is used to provide low-pressure unloading when in standby mode, with low unloading noise and energy saving.

[0021] (5) The multi-way valve of the present invention integrates a telescopic switching valve, which is used to switch the telescopic cylinder control during hydraulic control. The integration of the above valve simplifies the system pipeline connection, reduces costs, and reduces leakage points and failure points.

[0022] (6) The multi-way valve of the present invention adopts post-valve compensation. The LS pressure acts on the compensator spring chamber through the damping and the one-way valve. The compensator opens slowly and closes quickly, which not only ensures the rapidity of load-sensitive response, but also realizes the stability of the compensator during compound actions.

[0023] (7) The three-way pressure compensator in the multi-way valve of the present invention adopts a double spring design, so that the diverter valve can be opened quickly, reducing the influence of the three-way pressure compensator on the working hysteresis loop. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the principle of the multi-way valve of the present invention; Figure 2 It is a structural schematic diagram of a standby low-pressure unloading valve in a multi-way valve of the present invention; Figure 3 It is a schematic diagram of the structure of a three-way pressure compensator in a multi-way valve of the present invention; Figure 4 This is a schematic diagram of the structure of the compensator in the multi-way valve of the present invention; Figure 5 It is a schematic diagram of the groove damping structure of the compensator in the multi-way valve of the present invention.

[0025] Reference numerals: 1. First joint; 2. Working joint; 3. Swing valve; 4. Swing brake release valve; 5. Dangerous condition unloading valve; 6. Standby low-pressure unloading valve; 7. Three-way pressure compensator; 8. Telescopic switching valve; 9. Safety valve; 10. First damping; 11. Second damping; 12. Main valve core; 13. Compensator; 14. Second check valve; 15. First check valve; Working oil port of working joint: A1, B1, A2, B2, A3, B3, A4, B4; Working pilot oil port: a1, b1, a2, b2, a3, b3, a4, b4; Oil inlet P1, P2; oil return port T1, T2; 6.1. Cone valve; 6.2. Spring of standby low-pressure unloading valve; 6.3. Plug; 7.1. Left screw plug; 7.2. First spring; 7.3. Three-way pressure compensator valve core; 7.4. Second spring; 7.5 Right screw plug; 13.1. Screw plug; 13.2. Compensator spring; 13.3. Third one-way valve; 13.4. Groove damping; 13.5. Third damping; 13.6. Compensator valve core. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0027] like Figure 1 As shown, the impact-proof low-hysteresis integrated multi-way valve proposed in the present invention has a valve body that is integrally cast and is provided with a D port, a T1 port, an L port, a K port, a LS port, a P1 port, a P2 port, a T1 port and a T2 port, and also includes a first joint 1, a working joint 2, and a rotary valve 3; the first joint 1 includes a rotary brake release valve 4, a dangerous condition unloading valve 5, a standby low-pressure unloading valve 6, a three-way pressure compensator 7, a telescopic switching valve 8, a safety valve 9, a first damper 10, a second damper 11, and a first check valve 15; the working joint 2 includes a main volume joint, an auxiliary volume joint, a variable amplitude joint, and a telescopic joint, and each joint has the same structure and mainly includes a main valve core 12, a compensator 13, and a second check valve 14.

[0028] The power source metering pump is connected to the P1 port to provide a constant flow for the multi-way valve. The P1 port is connected to the a port of the three-way pressure compensator 7, the a port of the telescopic switching valve 8, one end of the safety valve 9 and the P port of the main valve core; the T1 port is connected to the b port of the standby low-pressure unloading valve 6, the b port of the three-way pressure compensator 7, the other end of the safety valve 9 and the T port of the main valve core; the LS port is connected to the c port of the dangerous working condition unloading valve 5, the spring chamber of the three-way pressure compensator 7 and the b port of the compensator 13, and the LS port is connected to the T1 port through the second damping 11 and the first damping 10; the L port is connected to the a port of the swing brake release valve 4, the a port of the dangerous working condition unloading valve 5 and the b port of the telescopic switching valve 8; the K port is connected to the swing brake release valve 4. The c port of the swing brake release valve 4 is connected; the D port is connected to the c port of the telescopic switching valve 8; the b port of the dangerous condition unloading valve 5 is connected to the spring chamber of the standby low-pressure unloading valve 6; the P' port of the main valve core 12 is connected to the a port of the compensator 13 and is connected to the b port of the swing brake release valve 4 through the second one-way valve 14, the P" port of the main valve core 12 is connected to the c port of the compensator 13, and the A port and B port of the main valve core 12 are connected to the working oil port; the P2 port is connected to the b port of the swing brake release valve 4 through the first one-way valve 15 and is used for the oil supply of the swing valve, and the T2 port is used for the oil return of the swing valve. For the hydraulically controlled multi-way valve, the pilot oil ports a and b are connected to the pilot handle oil port that controls the action of the main valve core 12.

[0029] like Figure 2As shown, the standby low-pressure unloading valve 6 includes a cone valve 6.1, a standby low-pressure unloading valve spring 6.2 and a plug 6.3. The pressure at the P1 port acts on the right chamber of the cone valve, and the LS pressure acts on the spring chamber of the left chamber of the cone valve through the dangerous working condition unloading valve 5. The plug 6.3 limits the stroke of the cone valve 6.1, wherein the area of ​​the spring chamber is much larger than the area of ​​the right chamber, and the equivalent pressure of the standby low-pressure unloading valve spring 6.2 is very small.

[0030] like Figure 3 As shown, the three-way pressure compensator 7 comprises a left screw plug 7.1, a first spring 7.2, a three-way pressure compensator valve core 7.3, a second spring 7.4 and a right screw plug 7.5, and adopts a double-spring two-end arrangement structure, the first spring 7.2 is located at the left end, and the LS pressure acts on the first spring cavity, the second spring 7.4 is located at the right end, and the P1 port pressure acts on the second spring cavity; the left screw plug 7.1 and the right screw plug 7.5 limit the stroke of the three-way pressure compensator valve core, the compression amount of the second spring 7.4 is the covering amount of the three-way pressure compensator valve core 7.3, from P1-T being connected to P1-T being fully open, the equivalent pressure of the two springs is basically a constant, that is, when the P1-LS pressure is greater than the equivalent pressure of the two springs, the three-way pressure compensator 7 is opened.

[0031] like Figure 4 As shown, the compensator 13 includes a screw plug 13.1, a compensator spring 13.2, a third one-way valve 13.3, a groove damper 13.4, a third damper 13.5, and a compensator valve core 13.6. The P' port pressure acts on the lower end of the compensator valve core 13.6, and the LS pressure acts on the compensator spring cavity through the third one-way valve 13.3, the third damper 13.5 and the groove damper 13.4. The equivalent pressure of the compensator spring 13.2 is very small. Therefore, when the compensator valve core 13.6 reaches a balanced state under the compensator spring 13.2, the LS pressure and the P' port pressure, the P' port pressure is almost equal to the LS pressure; the screw plug 13.1 and the valve body limit the stroke of the compensator valve core 13.6.

[0032] like Figure 5 As shown, the groove damping 13.4 is a concave groove milled from top to bottom on the outer diameter of the compensator valve core 13.6. The oil in the compensator spring chamber can only flow out through the groove damping 13.4. The oil in the compensator 13 can flow into the compensator spring chamber through the groove damping 13.4, and can also flow into the compensator spring chamber through the third damping 13.5 and the third one-way valve 13.3, thereby realizing slow opening and fast closing of the compensator.

[0033] Taking the hydraulically controlled multi-way valve as an example, when the pilot handle is not operated, there is no pressure at the pilot oil port a and the oil port b of the multi-way valve, the main valve core 12 does not change direction and is located in the middle position, the pressure at the P' port of the main valve core 12 is zero, the compensator valve core 13.6 does not move, and the LS pressure is almost zero. Since the equivalent pressure of the standby low-pressure unloading valve spring 6.2 is much smaller than the equivalent pressure of the two springs of the three-way pressure compensator 7, the standby low-pressure unloading valve 6 is opened, and the oil from the metering pump returns to the T1 port from the standby low-pressure unloading valve 6, thereby realizing low-pressure unloading of the metering pump flow in standby mode, with low noise and low power.

[0034] When the single-link is in action, the pilot handle of the single-link is gradually pushed, and the pressure of the pilot oil port a or oil port b of the multi-way valve gradually increases. The single-link main valve core 12 gradually changes direction, and the throttle port from the P port to the P' port gradually increases to fully open. The P port is connected to the P' port, and the pressure at the P' port is established. The compensator 13 moves upward under the pressure of the P' port, and the a port of the compensator 13 is connected to the c port and is connected to the A port or the B port of the main valve core 12 at the same time, and the a port of the compensator 13 is connected to the b port. The pressure of the P' port is fed back to the LS port, and the LS pressure acts on the compensator spring cavity through the third one-way valve 13.3, the third damping 13.5 and the groove damping 13.4; the equivalent pressure of the two springs of the three-way pressure compensator 7 is not enough to offset the area difference between the spring cavity and the right cavity of the standby low-pressure unloading valve, so the standby low-pressure unloading valve 6 is closed, and the three-way pressure compensator 7 is opened. At this time, the pressure difference before and after the throttle port of the main valve core is P- P' is approximately the equivalent pressure of the two springs of the three-way pressure compensator 7, so part of the flow of the quantitative pump flows through the working link 2 to the working oil port, and part flows through the three-way pressure compensator back to the T1 port.

[0035] During compound action, gradually push the pilot handles of the two groups, the main valve cores 12 of the two groups change direction, the throttle port from port P to port P' gradually increases to full open, and port P is connected to port P'. Pressure is built up at the P' port, and the compensator 13 moves upward under the pressure of the P' port. The a port of the compensator 13 is connected to the c port and is connected to the A port or the B port of the main valve core 12. The working oil port pressure of the one with the larger load pressure in the two links will be fed back to the a port of the compensator 13 through the c port of the compensator 13, so that the compensator 13 of this link moves upward, and the a port of the compensator 13 of this link is connected to the b port. The larger load pressure of this link is fed back to the LS port, and the LS pressure acts on the compensator spring chamber of the two links through the third one-way valve 13.3, the third damper 13.5 and the groove damper 13.4. At this time, the a port and the b port of the compensator 13 of the link with the smaller load are not connected, and the P' port pressure of this link is almost equal to the LS pressure and the P' port of the link with the larger load. Therefore, the pressure difference before and after the throttle port of the main throttle valve core 12 of the two links is equal, and the flow distribution through the two links is only related to the size of the throttle port of the two links, and has nothing to do with the load.

[0036] When the throttle opening from port P to port P' of the main valve core 12 gradually increases to fully open, the three-way pressure compensator 7 gradually closes from port a to port b; when the throttle opening from port P to port P' of the main valve core 12 gradually decreases to closed, the three-way pressure compensator 7 gradually opens from port a to port b from closed, and the second spring 7.4 of the three-way pressure compensator 7 can make the valve core open quickly, compensate for the friction and hydraulic force during opening, and reduce the influence of its multiple working hysteresis loops.

[0037] When the compensator 13 moves upward to open, the oil in the spring chamber of the compensator 13 can only flow out through the groove damper 13.4 to relieve the pressure in the spring chamber and open slowly; when the heavy load link cuts in and the LS pressure suddenly increases, causing the compensator 13 to move downward and close, the oil can flow into the spring chamber through the third one-way valve 13.3, the third damper 13.5 and the groove damper 13.4 to build up pressure and cause the compensator valve core 13.6 to move downward quickly. Therefore, the compensator 13 can open slowly and close quickly, which not only ensures the rapidity of load-sensitive response, but also realizes the stability of the compensator during compound actions.

[0038] When the multi-way valve is manually controlled, a swing brake release valve 4 is installed on the valve body 1. The swing brake release valve 4 is a two-position three-way solenoid valve, and the K port provides pressure for the swing brake release; when the swing brake release valve 4 is not energized, the c port is connected to the a port, that is, the K port is connected to the L port, and the swing brake release pressure is zero; when the swing brake release valve 4 is energized, the c port is connected to the b port, that is, the K port is connected to the b port, when there is pressure at the swing link oil inlet port P2, the P2 port acts on the b port of the swing brake release valve 4 through the first one-way valve 15, and the K port is the P2 port pressure, thereby realizing the release of the swing brake; or when there is pressure at the P' port of the working link reversing main valve core, the P' port pressure acts on the b port of the swing brake release valve 4 through the second one-way valve 14, and the K port is the P' port pressure, thereby realizing the release of the swing brake.

[0039] When the multi-way valve is manually controlled, a dangerous condition unloading valve 5 is installed on the valve body, and the dangerous condition unloading valve 5 is a two-position three-way solenoid valve; when the dangerous condition unloading valve 5 is not energized, port c is connected to port b, that is, LS pressure acts on the spring chamber of the standby low-pressure unloading valve 6, and LS pressure is not unloaded; when the dangerous condition unloading valve 5 is energized, port c is connected to port a, that is, LS pressure is unloaded to port L through the dangerous condition unloading valve 5, thereby realizing the unloading of system pressure under dangerous conditions.

[0040] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. At the same time, in the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the equipment or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. And in the drawings of the present invention, the filling pattern is only to distinguish the layers, without any other limitation.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An anti-shock low hysteresis integrated multi-way valve, characterized in that: The valve body of the multi-way valve is integrally cast and is provided with a D port, a T1 port, an L port, a K port, an LS port, a P1 port, a P2 port, a T1 port and a T2 port, and further comprises a first joint (1), a working joint (2) and a rotary valve (3); the first joint (1) comprises: a rotary brake release valve (4), a dangerous condition unloading valve (5), a standby low-pressure unloading valve (6), a three-way pressure compensator (7), a telescopic switching valve (8), a safety valve (9), a first damper (10), a second damper (11) and a first check valve (15); a power source quantitative pump is connected to the P1 port to provide a constant flow rate for the multi-way valve; the P1 port is connected to the three-way pressure compensator (7), the telescopic switching valve (8) and the safety valve (9) and the working connection (2); the T1 port is connected to the standby low-pressure unloading valve (6), the three-way pressure compensator (7), the safety valve (9) and the working connection (2); the LS port is connected to the dangerous working condition unloading valve (5), the three-way pressure compensator (7) and the working connection (2), and the LS port is connected to the T1 port through the second damper (11) and the first damper (10); the L port is connected to the swing brake release valve (4), the dangerous working condition unloading valve (5) and the telescopic switching valve (8); the K port is connected to the swing brake release valve (4); the D port is connected to the telescopic switching valve (8); the dangerous working condition unloading valve (5) is connected to the standby low-pressure unloading valve (6); the swing brake release valve (4) is connected to the working connection (2), and the P2 port is connected to the swing brake release valve (4) through the first non-return valve (15).

2. The anti-shock low hysteresis integrated multi-way valve according to claim 1, characterized in that: The working link (2) comprises a plurality of links, each link being provided with a pilot oil port and a working oil port, and each link comprising a main valve core (12), a compensator (13) and a second one-way valve (14); the main valve core (12) is respectively connected to the pilot oil port and the working oil port, the compensator (13) is connected to the main valve core (12), and the compensator (13) is connected to the swing brake release valve (4) via the second one-way valve (14).

3. The anti-shock low hysteresis integrated multi-way valve according to claim 2, characterized in that: The P1 port is connected to the a port of the three-way pressure compensator (7), the a port of the telescopic switching valve (8), one end of the safety valve (9) and the P port of the main valve core (12); the T1 port is connected to the b port of the standby low-pressure unloading valve (6), the b port of the three-way pressure compensator (7), the other end of the safety valve (9) and the T port of the main valve core (12); the LS port is connected to the c port of the dangerous working condition unloading valve (5), the spring chamber of the three-way pressure compensator (7) and the b port of the compensator (13), and the LS port is connected to the T1 port through the second damper (11) and the first damper (10); the L port is connected to the a port of the swing brake release valve (4), the a port of the dangerous working condition unloading valve (5) and the port of the telescopic switching valve (8); The b port is connected; the K port is connected to the c port of the swing brake release valve (4); the D port is connected to the c port of the telescopic switching valve (8); the b port of the dangerous condition unloading valve (5) is connected to the spring chamber of the standby low-pressure unloading valve (6); the P' port of the main valve core (12) is connected to the a port of the compensator (13) and is connected to the b port of the swing brake release valve (4) through the second non-return valve (14); the P" port of the main valve core (12) is connected to the c port of the compensator (13); the A port and the B port of the main valve core (12) are connected to the working oil port; the P2 port is connected to the b port of the swing brake release valve (4) through the first non-return valve (15); and the pilot oil port is connected to the pilot handle oil port for controlling the action of the main valve core (12).

4. The anti-shock low hysteresis integrated multi-way valve according to claim 1, characterized in that: The standby low-pressure unloading valve (6) comprises a cone valve (6.1), a standby low-pressure unloading valve spring (6.2) and a plug (6.3); the cone valve (6.1) is provided with a right chamber and a spring chamber; the pressure at the P1 port acts on the right chamber; the LS pressure acts on the spring chamber via the hazardous condition unloading valve (5); and the plug (6.3) is used to limit the stroke of the cone valve (6.1).

5. The anti-shock low hysteresis integrated multi-way valve according to claim 1, characterized in that: The three-way pressure compensator (7) comprises a left screw plug (7.1), a first spring (7.2), a three-way pressure compensator valve core (7.3), a second spring (7.4) and a right screw plug (7.5). The first spring (7.2) is located at the left end, and the LS pressure acts on the first spring chamber. The second spring (7.4) is located at the right end, and the P1 port pressure acts on the second spring chamber. The left screw plug (7.1) and the right screw plug (7.5) are used to limit the stroke of the three-way pressure compensator valve core (7.3). The compression amount of the second spring (7.4) is the covering amount of the three-way pressure compensator valve core (7.3). From the connection between the P1 port and the T port to the full opening of the P1-T port, the equivalent pressure of the first spring (7.2) and the second spring (7.4) is a constant value. When the P1 port-LS pressure is greater than the equivalent pressure of the first spring (7.2) and the second spring (7.4), the three-way pressure compensator (7) is opened.

6. The anti-shock low hysteresis integrated multi-way valve according to claim 3, characterized in that: The compensator (13) comprises a screw plug (13.1), a compensator spring (13.2), a third one-way valve (13.3), a groove damper (13.4), a third damper (13.5) and a compensator valve core (13.6); the pressure at the P' port acts on the lower end of the compensator valve core (13.6); the LS pressure acts on the compensator spring chamber through the third one-way valve (13.3), the third damper (13.5) and the groove damper (13.4); when the compensator valve core (13.6) reaches a balanced state under the compensator spring (13.2), the LS pressure and the P' port pressure, the P' port pressure is nearly equal to the LS pressure; the screw plug (13.1) limits the stroke of the compensator valve core (13.6).

7. The control method of the anti-shock low hysteresis integrated multi-way valve according to claim 6, characterized in that: When the pilot handle is not operated, there is no pressure in the pilot oil port, the main valve core (12) is in the middle position, the pressure at the P' port of the main valve core (12) is zero, the compensator valve core (13.6) does not move, the LS pressure is close to zero, the standby low-pressure unloading valve (6) opens, and the oil from the metering pump returns to the T1 port from the standby low-pressure unloading valve (6).

8. The control method of the anti-shock low hysteresis integrated multi-way valve according to claim 6, characterized in that: When the single link in the working link (2) needs to be actuated, the pilot handle of the single link is pushed, the pressure of the pilot oil port increases, the main valve core (12) changes direction, the throttle port from the P port to the P' port increases to fully open, the P port is connected to the P' port, the P' port builds up pressure, the compensator (13) moves upward under the pressure of the P' port, the a port of the compensator (13) is connected to the c port, and is connected to the A port or the B port of the main valve core (12), and the a port of the compensator (13) is connected to the b port, the P' port pressure is fed back to the LS port, and the LS pressure acts on the compensator spring chamber through the third check valve (13.3), the third damper (13.5) and the groove damper (13.4); the standby low-pressure unloading valve (6) is closed, the three-way pressure compensator (7) is opened, part of the flow of the quantitative pump flows through the working link (2) to the working oil port, and part flows through the three-way pressure compensator (7) back to the T1 port.

9. The control method of the anti-shock low hysteresis integrated multi-way valve according to claim 6, characterized in that: When the two links in the working link (2) need to perform a compound action, the pilot handles of the two links are pushed, the main valve cores (12) of the two links are switched, the throttle port from the P port to the P' port is increased to fully open, the P port is connected to the P' port, the P' port builds up pressure, the compensator (13) moves upward under the pressure of the P' port, the a port of the compensator (13) is connected to the c port, and is connected to the A port or the B port of the main valve core (12); the working oil port pressure of the link with the larger load pressure in the two links is fed back to the a port of the compensator (13) through the c port of the compensator (13), so that the compensator (13) of this link moves upward, and the a port of the compensator (13) of this link is connected to the b port, and the larger load pressure of this link is fed back to the LS port , LS pressure acts on the spring chamber of the two-link compensator through the third non-return valve (13.3), the third damper (13.5) and the groove damper (13.4); at this time, the port a and the port b of the compensator (13) of the link with the smaller load are not connected, and the pressure of the port P' of this link is nearly equal to the LS pressure and the port P' of the link with the larger load. Therefore, the pressure difference before and after the throttle port of the main throttle valve core (12) of the two links is equal, and the flow distribution through the two links is only related to the size of the throttle port of the two links, and has nothing to do with the load.

10. The control method of the anti-shock low hysteresis integrated multi-way valve according to claim 3, characterized in that: When the multi-way valve is manually controlled, port K provides pressure for the swing brake release valve (4); when the swing brake release valve (4) is not energized, port c of the swing brake release valve (4) is connected to port a, that is, port K is connected to port L, and the swing brake release pressure is zero; when the swing brake release valve (4) is energized, port c of the swing brake release valve (4) is connected to port b, that is, port K is connected to port b of the swing brake release valve (4), when port P2 has pressure, port P2 acts on port b of the swing brake release valve (4) through the first check valve (15), and port K is the pressure of port P2, thereby releasing the swing brake; or when port P' of the main valve core (12) has pressure, port P' pressure acts on port b of the swing brake release valve (4) through the second check valve (14), and port K is the pressure of port P', thereby releasing the swing brake; When the hazardous condition unloading valve (5) is not energized, the port c of the hazardous condition unloading valve (5) is connected to the port b, that is, the LS pressure acts on the spring chamber of the standby low-pressure unloading valve (6), and the LS pressure is not unloaded; when the hazardous condition unloading valve (5) is energized, the port c of the hazardous condition unloading valve (5) is connected to the port a, that is, the LS pressure is unloaded to the port L through the hazardous condition unloading valve (5), thereby realizing the unloading of the system pressure under hazardous conditions.

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