Double-proportion type high-water-base proportional valve

Abstract

The invention discloses a double-proportion type high water base proportional valve. A liquid return valve element is arranged at the left end in the double-proportion type high-water-base proportional valve shell in a sliding mode, a valve sleeve is fixedly installed at the right end in the double-proportion type high-water-base proportional valve shell, and a valve seat and a load valve element are arranged in the valve sleeve. The inner cavities of the liquid return valve core, the valve seat and the load valve core are communicated with a load end port A; a liquid inlet runner is formed between the valve seat and the load valve element, a liquid return runner is formed between the liquid return valve element and the inner wall of the shell, an annular control cavity and an annular control protrusion which are in sliding sealing fit with each other are arranged between the load valve element and the valve sleeve, and the annular control cavity is divided into a left control cavity and a right control cavity through the annular control protrusion. The pressure difference between the left control cavity and the right control cavity drives the load valve element to slide, so that the double-proportion type high-water-base proportional valve is switched between the working positions, and the flow is proportionally controlled under the double working positions. The double-proportion type high-water-base proportional valve has good control at the PA working position and the AT working position, the degree of freedom is low, and the proportional effect can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of proportional valves, and in particular to a dual-proportional high-water-based proportional valve. Background Art

[0002] The high water-based proportional valve is a hydraulic valve used for pure water or emulsion medium flow regulation, mainly used in coal mines and other places that require explosion protection. The high water-based hydraulic cylinder of the hydraulic system of the left fully-mechanized mining face is mainly controlled by the time of the switch valve, which often causes the problem of over-extension or over-contraction of the hydraulic cylinder, and the posture control of the hydraulic support cannot be guaranteed. In order to break through the bottleneck of the difficulty in accurately controlling the posture of the hydraulic support, a high water-based proportional valve with stepless flow regulation function is urgently needed.

[0003] Existing high water-based proportional valves are divided into three categories. The first category is controlled by a high-speed switch valve pilot, such as CN116607989A (a water-based proportional valve) and CN111894924A (a high-water-based, high-pressure, and large-flow digital proportional directional valve with manual and automatic control); the second category is controlled by a motor pilot, such as CN109555740B (a water-based proportional valve and its control method) and CN117329189A (a follow-up pilot water-based proportional valve); the third category is a hydraulic balance scheme controlled by a pilot pressure reducing valve, such as CN113685387B (a pressure-balanced water-based proportional reversing valve) and CN115653961A (a high water-based proportional directional valve and its working method).

[0004] Due to the requirements for mining sealing, the above solutions are all proportional valves with two-position three-way cone valve structure, but the return oil working position is all switch type, and only the oil inlet working position is proportional. There is room for improvement in control freedom and energy saving. Summary of the invention

[0005] The present invention aims to solve the problem that the existing water-based proportional valve has only a unilateral proportional function, and provides a dual-proportional high water-based proportional valve. The water-based proportional valve of the present invention has the advantages of dual proportions of liquid inlet and liquid return, easy load independent control and energy saving.

[0006] The technical solution adopted by the present invention is:

[0007] 1. A dual-proportional high water-based proportional valve

[0008] The dual-proportional high-water-based proportional valve comprises a housing and a load valve core, a valve sleeve, a valve seat and a liquid return valve core coaxially arranged inside the housing; the housing is provided with a liquid return T port, a liquid inlet P port, a left control chamber K1 port, a right control chamber K2 port and a load end A port.

[0009] A liquid return valve core is slidably arranged at the left end of the shell, and a valve sleeve is arranged at the right end. A valve seat and a load valve core are slidably arranged in the valve sleeve from left to right in sequence; the valve sleeve is fixedly connected to the shell, and the inner cavity of the liquid return valve core, the inner cavity of the valve seat, the inner cavity of the load valve core and the load end A port are connected.

[0010] A liquid inlet channel is formed between the valve seat and the load valve core, and the load valve core slides to open or close the liquid inlet channel. The liquid inlet channel is opened so that the liquid inlet port P is connected to the inner cavity of the valve seat; a liquid return channel is formed between the liquid return valve core and the inner wall of the shell, and the liquid return valve core slides to open or close the liquid return channel. The liquid return channel is opened so that the liquid return port T is connected to the inner cavity of the valve seat.

[0011] An annular control chamber and an annular control protrusion that slide and seal with each other are provided between the load valve core and the valve sleeve. The annular control protrusion divides the annular control chamber into a left control chamber and a right control chamber. The left control chamber is connected to the left control chamber K1 port, and the right control chamber is connected to the right control chamber K2 port. The pressure difference between the left control chamber and the right control chamber drives the load valve core to slide, thereby enabling the dual-proportional high-water-based proportional valve to switch between the intermediate working position, the PA working position and the AT working position, and proportionally control the flow in the PA working position and the AT working position.

[0012] In the middle working position, the return liquid flow channel and the liquid inlet flow channel are closed, and the return liquid T port, the liquid inlet P port and the load end A port are not connected to each other; in the PA working position, the return liquid flow channel is closed, the liquid inlet flow channel is connected, and the liquid inlet P port is connected to the load end A port; in the AT working position, the return liquid flow channel is connected, the liquid inlet flow channel is closed, and the return liquid T port is connected to the load end A port.

[0013] The dual-proportional high-water-based proportional valve also includes a load spring arranged in the inner cavity of the load valve core, and a liquid return spring and a valve seat reset spring arranged in the inner cavity of the liquid return valve core; the two ends of the load spring respectively press against the inner end surface of the right end of the shell and the inner end surface of the left end of the load valve core; the two ends of the liquid return spring respectively press against the inner end surface of the left end of the shell and the inner end surface of the right end of the liquid return valve core; the two ends of the valve seat reset spring respectively press against the inner end surface of the left end of the shell and the outer end surface of the left end of the valve seat.

[0014] The valve seat is mainly composed of a left working section, a middle working section and a right working section, the outer diameters of which increase successively; the right working section and the load valve core form a liquid inlet channel on the left side of the liquid inlet P port; the right working section is provided with a flange, which is slidably arranged in an annular limiting cavity, and the annular limiting cavity is mainly enclosed by the outer wall of the valve seat and the stepped groove on the inner wall of the valve sleeve, and a through hole is provided on the inner wall of the groove bottom of the stepped groove, so that the annular limiting cavity is connected with the liquid inlet P port; the outer wall surface of the middle working section is in sliding sealing cooperation with the inner wall surface of the shell or the valve sleeve; the left working section extends into the liquid return valve core and is connected with the liquid return valve core in a sliding sealing manner, and the outer end surface of the left working section serves as a supporting surface for the valve seat reset spring.

[0015] The liquid return valve core and the shoulder on the inner side of the shell form a liquid return flow channel on the right side of the liquid return T port. The center of the right end surface of the liquid return valve core extends axially toward the right side to form an extension portion with a smaller diameter. The extension portion of the liquid return valve core is sleeved on the outer side of the left working section of the valve seat, and the middle working section of the valve seat and the extension portion of the liquid return valve core are arranged at intervals. A liquid return cavity is formed between the extension portion of the liquid return valve core and the inner wall of the shell. The liquid return cavity is connected with the liquid return T port through the liquid return flow channel. A plurality of through holes are opened on the end surface of the middle working section of the valve seat, so that the liquid return cavity is connected with the inner cavity of the valve seat.

[0016] The center of the left end surface of the load valve core extends axially toward the left side to form an extension portion with a smaller diameter, and the extension portion of the load valve core extends into the inner cavity of the valve seat; a plurality of first connecting holes are arranged around the outer peripheral surface of the extension portion of the load valve core, and a second connecting hole is arranged on the left end surface, so that the inner cavity of the load valve core is connected with the inner cavity of the valve seat.

[0017] The outer circumference of the valve sleeve is provided with a first annular groove and a second annular groove, and the first annular groove and the second annular groove are respectively connected with the left control chamber K1 port and the right control chamber K2 port; the inner wall of the valve sleeve is provided with a third annular groove, and the third annular groove and the load valve core form an annular control chamber; the inner wall of the groove bottom of the first annular groove is provided with a plurality of circumferentially distributed through holes, so that the left control chamber K1 port, the first annular groove and the left control chamber in the annular control chamber are connected; the inner wall of the groove bottom of the second annular groove is provided with a plurality of circumferentially distributed through holes, so that the right control chamber K2 port, the second annular groove and the right control chamber in the annular control chamber are connected.

[0018] A fourth annular groove is provided on the outer periphery of the valve sleeve, which is connected to the liquid inlet P port. A plurality of circumferentially distributed through holes are provided on the inner wall of the bottom of the fourth annular groove, so that the liquid inlet P port, the fourth annular groove and the liquid inlet channel are connected.

[0019] The shell is mainly formed by sealingly connecting a left end cover, an outer shell and a right end cover.

[0020] There is always a gap between the liquid return valve core and the inner wall surface of the left end of the shell; there is always a gap between the load valve core and the inner wall surface of the right end of the shell.

[0021] 2. A control method using the above-mentioned dual-proportional high water-based proportional valve

[0022] The following steps are involved:

[0023] Keep the pressure of the left control chamber and the right control chamber the same or without pressure, so that the annular control protrusion is located in the center of the annular control chamber, the flange on the right working section of the valve seat abuts against the right side wall of the annular limit chamber, the right end face of the right working section of the valve seat is sealed with the left end face of the load valve core, the liquid inlet flow channel is closed, the right end face of the liquid return valve core is sealed with the left side face of the shoulder on the inner side of the shell, the liquid return flow channel is closed, and the proportional valve is in the middle working position, and the liquid return T port, the liquid inlet P port and the load end A port are not connected to each other;

[0024] Increase the liquid pressure in the left control chamber so that the pressure in the left control chamber is greater than the pressure in the right control chamber. The pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the load spring on the load valve core, driving the load valve core to move rightward, and the right end surface of the right working section of the valve seat is separated from the left end surface of the load valve core. The liquid inlet channel is connected, and the liquid inlet port P, the liquid inlet channel, the inner cavity of the valve seat, the inner cavity of the load valve core and the load end A port are connected, thereby switching the proportional valve to the PA working position, and the liquid inlet port P is connected to the load end A port; in the PA working position, adjust the pressure of the left control chamber K1 port according to the target flow rate until the flow rate of the liquid flowing out of the load end A port reaches the target flow rate;

[0025] Increase the liquid pressure in the right control chamber so that the pressure in the left control chamber is less than that in the right control chamber. The pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the valve seat return spring on the valve seat, drives the load valve core to drive the valve seat to move left synchronously, and the pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the return spring and the valve seat return spring, drives the load valve core to drive the valve seat and the return valve core to move left synchronously, so that the right end face of the return valve core is separated from the left side face of the shoulder on the inner side of the shell, the return liquid flow channel is connected, the return liquid T port, the return liquid flow channel, the return liquid chamber, the inner cavity of the valve seat, the inner cavity of the load valve core and the load end A port are connected, and then the proportional valve is switched to the AT working position, and the return liquid T port is connected to the load end A port; in the AT working position, adjust the pressure of the left control chamber K1 port according to the target flow rate until the flow rate of the liquid flowing out of the return liquid T port reaches the target flow rate.

[0026] The beneficial effects of the present invention are as follows:

[0027] The present invention designs a dual-proportional high-water-based proportional valve, which overcomes the problem that the existing high-water-based proportional valve has a proportional effect only in the PA working position and has a low control freedom in the AT working position switch control, and is conducive to realizing independent control of the valve port and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the dual-proportional high water-based proportional valve in the present invention in the middle working position;

[0029] Figure 2 It is a structural schematic diagram of the dual-proportional high water-based proportional valve in the present invention in the PA working position;

[0030] Figure 3 It is a partial enlarged view of the main valve port (liquid inlet P port) of the dual-proportional high water-based proportional valve in the present invention;

[0031] Figure 4 It is a structural schematic diagram of the dual-proportional high water-based proportional valve in the present invention in the AT working position.

[0032] In the figure: 1. left end cover, 2. outer shell, 2.1. liquid return T port, 2.2. liquid inlet P port, 2.3. left control chamber K1 port, 2.4. right control chamber K2 port, 3. right end cover, 3.1. load end A port, 4. load spring, 5. load valve core, 6. valve sleeve, 7. valve seat, 8. liquid return valve core, 9. liquid return spring, 10. valve seat return spring. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] A first aspect of the present invention provides a dual-proportional high-water-based proportional valve.

[0035] The dual-proportional high water-based proportional valve of the present invention comprises a housing and a load valve core 5, a valve sleeve 6, a valve seat 7 and a liquid return valve core 8 coaxially arranged inside the housing. Figure 1 As shown, the outer wall of the housing is provided with a return liquid T port 2.1, a liquid inlet P port 2.2, a left control chamber K1 port 2.3 and a right control chamber K2 port 2.4 in sequence from left to right, and a load end A port 3.1 is provided at the right end of the housing. Specifically, the return liquid T port 2.1, the liquid inlet P port 2.2, the left control chamber K1 port 2.3 and the right control chamber K2 port 2.4 are all provided along the radial direction of the dual-proportional high water-base proportional valve, and the load end A port 3.1 is provided along the axial direction of the dual-proportional high water-base proportional valve.

[0036] A liquid return valve core 8 is slidably arranged at the left end inside the shell, and a valve sleeve 6 is arranged at the right end inside the shell. A valve seat 7 and a load valve core 5 are slidably arranged in the valve sleeve 6 from left to right in sequence. The valve sleeve 6 is fixedly connected to the shell, and the inner cavity of the liquid return valve core 8, the inner cavity of the valve seat 7, the inner cavity of the load valve core 5 and the load end A port 3.1 are connected.

[0037] A return liquid flow channel and a liquid inlet flow channel are provided inside the shell, which are connected to the return liquid T port 2.1 and the liquid inlet P port 2.2 respectively. Specifically, a liquid inlet flow channel is formed between the valve seat 7 and the load valve core 5, and the load valve core 5 slides to open or close the liquid inlet flow channel. The liquid inlet flow channel is opened so that the liquid inlet P port 2.2 is connected to the inner cavity of the valve seat 7, and then the liquid inlet P port 2.2, the liquid inlet flow channel, the inner cavity of the valve seat 7, the inner cavity of the load valve core 5 and the load end A port 3.1 are connected in sequence. A return liquid flow channel is formed between the return liquid valve core 8 and the inner wall of the shell, and the return liquid valve core 8 slides to open or close the return liquid flow channel. The return liquid flow channel is opened so that the return liquid T port 2.1 is connected to the inner cavity of the valve seat 7, and then the return liquid T port 2.1, the return liquid flow channel, the inner cavity of the valve seat 7, the inner cavity of the load valve core 5 and the load end A port 3.1 are connected in sequence.

[0038] In a specific implementation, the liquid return valve core 8 and the shoulder on the inner wall of the shell form a liquid return flow channel.

[0039] In a specific implementation, the liquid inlet channel is located on the left side of the liquid inlet P port 2.2, and the liquid return channel is located on the right side of the liquid return T port 2.1.

[0040] The working state switching and flow control of the dual-proportional high-water-based proportional valve are realized by the load valve core 5 moving left and right along the axial direction, and the left and right movement control of the load valve core 5 is realized by the pressure difference between the left control chamber K1 port 2.3 and the right control chamber K2 port 2.4. The left and right movement control of the load valve core 5 is realized in the following manner: an annular control chamber is arranged between the load valve core 5 and the valve sleeve 6, an annular control protrusion is arranged on the outside of the load valve core 5, the outer peripheral surface of the annular control protrusion is slidably sealed with the inner peripheral surface of the annular control chamber, and the annular control protrusion separates the annular control chamber into a left control chamber and a right control chamber, the left control chamber and the right control chamber are not connected to each other, the left control chamber is connected to the left control chamber K1 port 2.3, and the right control chamber is connected to the right control chamber K2 port 2.4, and the pressure difference between the left control chamber and the right control chamber can drive the load valve core 5 to slide, thereby switching the proportional valve between the middle working position, the PA working position and the AT working position.

[0041] When the proportional valve switches between the intermediate working position, the PA working position and the AT working position, in the intermediate working position, the return liquid flow channel and the liquid inlet flow channel are closed, and the return liquid T port 2.1, the liquid inlet P port 2.2 and the load end A port 3.1 are not connected to each other; in the PA working position, the return liquid flow channel is closed, the liquid inlet flow channel is connected, and the liquid inlet P port 2.2 and the load end A port 3.1 are connected; in the AT working position, the return liquid flow channel is connected, the liquid inlet flow channel is closed, and the return liquid T port 2.1 and the load end A port 3.1 are connected.

[0042] The dual-proportional high-water-base proportional valve also includes a load spring 4 arranged in the inner cavity of the load valve core 5, and a liquid return spring 9 and a valve seat return spring 10 arranged in the inner cavity of the liquid return valve core 8. The two ends of the load spring 4 respectively abut against the inner end surface of the right end of the housing and the inner end surface of the left end of the load valve core 5; the two ends of the liquid return spring 9 respectively abut against the inner end surface of the left end of the housing and the inner end surface of the right end of the liquid return valve core 8; the two ends of the valve seat return spring 10 respectively abut against the inner end surface of the left end of the housing and the outer end surface of the left end of the valve seat 7. The load spring 4, the liquid return spring 9 and the valve seat return spring 10 are all in a compressed state in the middle working position.

[0043] Specifically, the housing is mainly formed by the sealed connection of the left end cover 1, the outer shell 2 and the right end cover 3. The left part of the outer shell 2 accommodates the liquid return function component (mainly composed of the liquid return valve core 8), on which a liquid return T port 2.1 is opened, which is limited and sealed by the left end cover 1. The right part accommodates the liquid inlet function component (mainly composed of the load valve core 5, the valve sleeve 6 and the valve seat 7), on which a liquid inlet P port 2.2, a left control chamber K1 port 2.3 and a right control chamber K2 port 2.4 are opened, which are limited and sealed by the right end cover 3. The right end cover 3 is provided with a load end A port 3.1. The two ends of the load spring 4 respectively abut the left side surface of the right end cover 3 and the inner end surface of the left end of the load valve core 5; the two ends of the liquid return spring 9 respectively abut the right side surface of the left end cover 1 and the inner end surface of the right end of the liquid return valve core 8; the two ends of the valve seat return spring 10 respectively abut the right side surface of the left end cover 1 and the outer end surface of the left end of the valve seat 7.

[0044] Specifically, the valve seat 7 is mainly composed of a left working section, a middle working section and a right working section, which are connected and have outer diameters that increase in sequence. The right end surface of the right working section and the left end surface of the load valve core 5 form a liquid inlet channel on the left side of the liquid inlet P port 2.2. A flange is provided at the left end of the right working section, and the flange is slidably arranged in the annular limiting cavity, and the outer peripheral surface of the flange is gap-matched with the inner peripheral surface of the annular limiting cavity. Figure 3 As shown, the annular limiting cavity is mainly enclosed by the outer wall of the valve seat 7 and the stepped groove on the inner wall of the valve sleeve 6. A through hole is provided on the inner wall of the bottom of the stepped groove, so that the annular limiting cavity is connected to the liquid inlet P port 2.2. The outer wall surface of the middle working section is in sliding sealing cooperation with the inner wall surface of the housing or the valve sleeve 6; the left working section extends into the interior of the liquid return valve core 8 and is connected to the liquid return valve core 8 in a sliding sealing connection, and the left outer end surface of the left working section serves as the support surface of the valve seat return spring 10.

[0045] In a specific implementation, the right outer end surface of the right working section and the left outer end surface of the load valve core 5 are both provided with conical surfaces. When the liquid inlet channel is closed, the two conical surfaces are sealed and fitted together. When the liquid inlet channel is open, the two conical surfaces are spaced apart.

[0046] Specifically, the right end face of the liquid return valve core 8 and the left side face of the shoulder on the inner side of the shell form a liquid return flow channel on the right side of the liquid return T port 2.1, and the center of the right end face of the liquid return valve core 8 extends axially toward the right side to form an extension portion with a smaller diameter than the main body of the liquid return valve core 8. The extension portion of the liquid return valve core 8 is sleeved on the outer side of the left working section of the valve seat 7, and the extension portion of the liquid return valve core 8 and the left working section of the valve seat 7 are connected in a sliding and sealing manner. A liquid return cavity is formed between the extension portion of the liquid return valve core 8 and the inner wall of the shell, and the liquid return cavity is located on the right side of the liquid return T port 2.1. The liquid return cavity is connected to the liquid return T port 2.1 through the liquid return flow channel, and a number of through holes evenly distributed along the circumferential direction are opened on the end face of the middle working section of the valve seat 7, so that the liquid return cavity is connected to the inner cavity of the valve seat 7.

[0047] Furthermore, the middle working section of the valve seat 7 and the extension of the liquid return valve core 8 are arranged at intervals, so that a dead zone, i.e., a transition distance, is formed between the valve seat 7 and the liquid return valve core 8. The setting of the dead zone can ensure that the two working positions PA and AT do not affect each other, that is, the load valve core 5 and the valve seat 7 move to the left together, and will not contact the liquid return valve core 8 until they cross the dead zone distance.

[0048] Furthermore, the right end surface of the liquid return valve core 8 and the left side surface of the shoulder inside the shell are both provided with conical surfaces. When the liquid return flow channel is closed, the two conical surfaces are sealed and fitted; when the liquid return flow channel is closed, the two conical surfaces are spaced apart.

[0049] Specifically, the center of the left end face of the load valve core 5 extends axially toward the left side to form an extension portion with a smaller diameter than the main body of the load valve core 5. The extension portion of the load valve core 5 extends into the inner cavity of the valve seat 7, specifically, the inner cavity of the middle working section and the right working section of the valve seat 7. The outer peripheral surface of the extension portion of the load valve core 5 is gap-matched with the inner peripheral surface of the valve seat 7, and a certain small gap is maintained between the outer end face on the left side of the extension portion of the load valve core 5 and the inner end face of the middle working section of the valve seat 7. A plurality of first connecting holes are provided around the outer periphery of the extension portion of the load valve core 5, and a second connecting hole is provided at the center of the left end face, so that the inner cavity of the load valve core 5 is connected with the inner cavity of the valve seat 7. In a specific implementation, the first connecting holes are all provided in the radial direction, and the second connecting holes are provided in the axial direction.

[0050] Further, the outer circumference of the valve sleeve 6 is provided with a first annular groove and a second annular groove, and the first annular groove and the second annular groove are respectively connected with the left control chamber K1 port 2.3 and the right control chamber K2 port 2.4 on the housing 2. The inner wall of the valve sleeve 6 is provided with a third annular groove, and the third annular groove and the load valve core 5 form an annular control chamber surrounding the load valve core 5. The width of the third annular groove is greater than the distance between the left control chamber K1 port 2.3 and the right control chamber K2 port 2.4. The inner wall of the groove bottom of the first annular groove is provided with a plurality of circumferentially evenly distributed through holes, so that the left control chamber K1 port 2.3, the first annular groove and the left control chamber in the annular control chamber are connected; the inner wall of the groove bottom of the second annular groove is provided with a plurality of circumferentially evenly distributed through holes, so that the right control chamber K2 port 2.4, the second annular groove and the right control chamber in the annular control chamber are connected.

[0051] Furthermore, a fourth annular groove is provided on the outer periphery of the valve sleeve 6, the fourth annular groove is connected to the liquid inlet P port 2.2, and a plurality of through holes evenly distributed along the circumferential direction are provided on the inner wall of the groove bottom of the fourth annular groove, so that the liquid inlet P port 2.2, the fourth annular groove and the liquid inlet channel are connected.

[0052] Furthermore, there is always a gap between the liquid return valve core 8 and the inner wall surface of the left end of the housing; there is always a gap between the load valve core 5 and the inner wall surface of the right end of the housing.

[0053] A second aspect of the present invention provides a control method for a dual-proportional high-water-based proportional valve.

[0054] The specific control method is:

[0055] like Figure 1 As shown, the pressures of the left control chamber and the right control chamber are kept the same or without pressure, so that the annular control protrusion is located in the center of the annular control chamber. At this time, the liquid enters the annular limiting chamber from the liquid inlet P port 2.2, and the valve seat 7 is subjected to the rightward pressure of the liquid inlet P port 2.2 and the rightward elastic force of the valve seat return spring 10, so that the flange on the right working section of the valve seat 7 abuts against the right side wall of the annular limiting chamber, and the valve seat 7 is pressed tightly against the valve sleeve 6. At the same time, the load valve core 5 is also pressed tightly against the valve seat 7 due to the leftward elastic force of the load spring 4, and the right end face of the right working section of the valve seat 7 is sealed and fitted with the left end face of the load valve core 5, and the liquid inlet flow channel is closed. Under the action of the liquid return spring 9, the liquid return valve core 8 is pressed tightly against the housing 2, so that the right end face of the liquid return valve core 8 is sealed and fitted with the left side face of the shoulder inside the housing, and the liquid return flow channel is closed, so that the proportional valve is in the middle working position. At this time, the liquid return T port 2.1, the liquid inlet P port 2.2 and the load end A port 3.1 of the high water base proportional valve are not connected to each other.

[0056] like Figure 2As shown, the liquid pressure of the left control chamber is increased, so that the pressure of the left control chamber is greater than the pressure of the right control chamber, and the pressure difference between the left control chamber and the right control chamber is greater than the elastic force of the load spring 4 on the load valve core 5, pushing the load valve core 5 to move to the right. Since the valve seat 7 is limited by the valve sleeve 6, the right end face of the right working section of the valve seat 7 is separated from the left end face of the load valve core 5, the liquid inlet flow channel is connected, and the liquid inlet P port 2.2, the fourth annular groove, the liquid inlet flow channel, the inner cavity of the valve seat 7, the inner cavity of the load valve core 5 and the load end A port 3.1 are connected, so that the proportional valve is switched to the PA working position, and the liquid inlet P port 2.2 is connected to the load end A port 3.1. By controlling the pressure of the left control chamber K1 port 2.3, the opening between the load valve core 5 and the valve seat 7 is controlled to change proportionally. In the PA working position, the pressure of the left control chamber K1 port 2.3 is adjusted according to the target flow until the flow of the liquid flowing out of the load end A port 3.1 reaches the target flow.

[0057] like Figure 4 As shown, the liquid pressure in the right control chamber is increased, so that the pressure in the left control chamber is less than that in the right control chamber, and the pressure difference between the left control chamber and the right control chamber is greater than the elastic force of the valve seat return spring 10 on the valve seat 7, driving the load valve core 5 to drive the valve seat 7 to move left synchronously. After crossing the dead zone distance, as the pressure of the right control chamber K2 port 2.4 continues to increase, the pressure difference between the left control chamber and the right control chamber is greater than the sum of the elastic forces of the liquid return spring 9 and the valve seat return spring 10, that is, the pressure difference overcomes the elastic forces of the liquid return spring 9 and the valve seat return spring 10 at the same time, driving the load valve core 5 to drive the valve seat 7 and the liquid return valve core 8 to move left synchronously, the right end face of the liquid return valve core 8 is separated from the left side face of the shoulder on the inner side of the shell, the liquid return flow channel is connected, the liquid return T port 2.1, the liquid return flow channel, the liquid return chamber, the inner cavity of the valve seat 7, the inner cavity of the load valve core 5 and the load end A port 3.1 are connected, so that the proportional valve is switched to the AT working position, and the liquid return T port 2.1 is connected to the load end A port 3.1. By controlling the pressure of the right control chamber K2 port 2.4, the opening between the return valve core 8 and the housing 2 is controlled to change proportionally. In the AT working position, the pressure of the left control chamber K1 port 2.3 is adjusted according to the target flow rate until the flow rate of the liquid outflowing from the return liquid T port 2.1 reaches the target flow rate.

[0058] The above is only an explanation of the best embodiment of the present invention, but it should not be understood as a limitation of the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to be changed. All changes made within the scope of protection of the independent claims of the present invention are within the scope of protection of the present invention.

[0059] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

Claims

1. A dual-proportional high water-based proportional valve, characterized in that: The dual-proportional high-water-base proportional valve comprises a housing, and a load valve core (5), a valve sleeve (6), a valve seat (7) and a liquid return valve core (8) coaxially arranged inside the housing; the housing is provided with a liquid return T port (2.1), a liquid inlet P port (2.2), a left control chamber K1 port (2.3), a right control chamber K2 port (2.4) and a load end A port (3.1); A liquid return valve core (8) is slidably disposed at the left end of the housing, and a valve sleeve (6) is arranged at the right end. A valve seat (7) and a load valve core (5) are slidably arranged in sequence from left to right in the valve sleeve (6); the valve sleeve (6) is fixedly connected to the housing, and the inner cavity of the liquid return valve core (8), the inner cavity of the valve seat (7), the inner cavity of the load valve core (5) and the load end A port (3.1) are in communication; A liquid inlet flow channel is formed between the valve seat (7) and the load valve core (5), and the load valve core (5) slides to open or close the liquid inlet flow channel, and the liquid inlet flow channel is opened so that the liquid inlet port (2.2) is connected to the inner cavity of the valve seat (7); a liquid return flow channel is formed between the liquid return valve core (8) and the inner wall of the shell, and the liquid return valve core (8) slides to open or close the liquid return flow channel, and the liquid return flow channel is opened so that the liquid return port (2.1) is connected to the inner cavity of the valve seat (7); An annular control chamber and an annular control protrusion which are slidably sealed with each other are arranged between the load valve core (5) and the valve sleeve (6); the annular control protrusion divides the annular control chamber into a left control chamber and a right control chamber; the left control chamber is connected to the left control chamber K1 port (2.3), and the right control chamber is connected to the right control chamber K2 port (2.4); the pressure difference between the left control chamber and the right control chamber drives the load valve core (5) to slide, thereby enabling the dual-proportional high-water-base proportional valve to switch between the intermediate working position, the PA working position and the AT working position, and proportionally control the flow in the PA working position and the AT working position; In the middle working position, the return liquid flow channel and the inlet liquid flow channel are closed, and the return liquid T port (2.1), the inlet liquid P port (2.2) and the load end A port (3.1) are not connected to each other; in the PA working position, the return liquid flow channel is closed, the inlet liquid flow channel is connected, and the inlet liquid P port (2.2) and the load end A port (3.1) are connected; in the AT working position, the return liquid flow channel is connected, the inlet liquid flow channel is closed, and the return liquid T port (2.1) and the load end A port (3.1) are connected.

2. A dual-proportional high water-based proportional valve according to claim 1, characterized in that: The dual-proportional high-water-based proportional valve further comprises a load spring (4) arranged in the inner cavity of the load valve core (5), and a liquid return spring (9) and a valve seat reset spring (10) arranged in the inner cavity of the liquid return valve core (8); the two ends of the load spring (4) respectively abut against the inner end surface of the right end of the housing and the inner end surface of the left end of the load valve core (5); the two ends of the liquid return spring (9) respectively abut against the inner end surface of the left end of the housing and the inner end surface of the right end of the liquid return valve core (8); the two ends of the valve seat reset spring (10) respectively abut against the inner end surface of the left end of the housing and the outer end surface of the left end of the valve seat (7).

3. A dual-proportional high water-based proportional valve according to claim 2, characterized in that: The valve seat (7) is mainly composed of a left working section, a middle working section and a right working section, the outer diameters of which are successively larger, and are connected to each other; the right working section and the load valve core (5) form a liquid inlet channel on the left side of the liquid inlet P port (2.2); the right working section is provided with a flange, which is slidably arranged in an annular limiting cavity, and the annular limiting cavity is mainly enclosed by the outer wall of the valve seat (7) and the stepped groove on the inner wall of the valve sleeve (6), and a through hole is opened on the inner wall of the groove bottom of the stepped groove, so that the annular limiting cavity is connected with the liquid inlet P port (2.2); the outer wall surface of the middle working section is in sliding sealing cooperation with the inner wall surface of the shell or the valve sleeve (6); the left working section extends into the liquid return valve core (8) and is connected to the liquid return valve core (8) in a sliding sealing manner, and the outer end surface of the left working section serves as a supporting surface for the valve seat reset spring (10).

4. A dual-proportional high water-based proportional valve according to claim 3, characterized in that: The liquid return valve core (8) and the shoulder on the inner side of the shell form a liquid return flow channel on the right side of the liquid return T port (2.1). The center of the right end surface of the liquid return valve core (8) extends axially toward the right side to form an extension portion with a smaller diameter. The extension portion of the liquid return valve core (8) is sleeved on the outer side of the left working section of the valve seat (7), and the middle working section of the valve seat (7) and the extension portion of the liquid return valve core (8) are arranged at intervals. A liquid return cavity is formed between the extension portion of the liquid return valve core (8) and the inner wall of the shell. The liquid return cavity is connected to the liquid return T port (2.1) through the liquid return flow channel. A plurality of through holes are provided on the end surface of the middle working section of the valve seat (7) so that the liquid return cavity is connected to the inner cavity of the valve seat (7).

5. A dual-proportional high water-based proportional valve according to claim 2, characterized in that: The center of the left end surface of the load valve core (5) extends axially toward the left side to form an extension portion with a smaller diameter, and the extension portion of the load valve core (5) extends into the inner cavity of the valve seat (7); a plurality of first connecting holes are arranged around the outer circumference of the extension portion of the load valve core (5), and a second connecting hole is arranged on the left end surface, so that the inner cavity of the load valve core (5) is connected to the inner cavity of the valve seat (7).

6. A dual-proportional high water-based proportional valve according to claim 1, characterized in that: The outer circumference of the valve sleeve (6) is provided with a first annular groove and a second annular groove, the first annular groove and the second annular groove are respectively connected to the left control chamber K1 port (2.3) and the right control chamber K2 port (2.4); the inner wall of the valve sleeve (6) is provided with a third annular groove, the third annular groove and the load valve core (5) form an annular control chamber; the inner wall of the groove bottom of the first annular groove is provided with a plurality of circumferentially distributed through holes, so that the left control chamber K1 port (2.3), the first annular groove and the left control chamber in the annular control chamber are connected; the inner wall of the groove bottom of the second annular groove is provided with a plurality of circumferentially distributed through holes, so that the right control chamber K2 port (2.4), the second annular groove and the right control chamber in the annular control chamber are connected.

7. A dual-proportional high water-based proportional valve according to claim 1, characterized in that: A fourth annular groove is provided on the outer periphery of the valve sleeve (6), the fourth annular groove being in communication with the liquid inlet P port (2.2), and a plurality of circumferentially distributed through holes are provided on the inner wall of the groove bottom of the fourth annular groove, so that the liquid inlet P port (2.2), the fourth annular groove and the liquid inlet flow channel are in communication.

8. A dual-proportional high water-based proportional valve according to claim 1, characterized in that: The shell is mainly formed by sealingly connecting a left end cover (1), an outer shell (2) and a right end cover (3).

9. A dual-proportional high water-based proportional valve according to claim 1, characterized in that: There is always a gap between the liquid return valve core (8) and the inner wall surface at the left end of the housing; there is always a gap between the load valve core (5) and the inner wall surface at the right end of the housing.

10. A control method using the dual-proportional high water-base proportional valve according to any one of claims 1 to 9, characterized in that: The pressures in the left control chamber and the right control chamber are kept the same or are pressure-free, so that the annular control protrusion is located in the center of the annular control chamber, the flange on the right working section of the valve seat (7) abuts against the right side wall of the annular limit chamber, the right end face of the right working section of the valve seat (7) is sealed against the left end face of the load valve core (5), the liquid inlet flow channel is closed, the right end face of the liquid return valve core (8) is sealed against the left side face of the shoulder inside the shell, the liquid return flow channel is closed, and the proportional valve is in the middle working position, and the liquid return T port (2.1), the liquid inlet P port (2.2) and the load end A port (3.1) are not connected to each other; The liquid pressure in the left control chamber is increased so that the pressure in the left control chamber is greater than the pressure in the right control chamber. The pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the load spring (4) on the load valve core (5), drives the load valve core (5) to move rightward, separates the right end surface of the right working section of the valve seat (7) from the left end surface of the load valve core (5), connects the liquid inlet flow channel, connects the liquid inlet P port (2.2), the liquid inlet flow channel, the inner cavity of the valve seat (7), the inner cavity of the load valve core (5) and the load end A port (3.1), thereby switching the proportional valve to the PA working position, connecting the liquid inlet P port (2.2) and the load end A port (3.1); in the PA working position, adjust the pressure of the left control chamber K1 port (2.3) according to the target flow rate until the flow rate of the liquid flowing out of the load end A port (3.1) reaches the target flow rate; The liquid pressure in the right control chamber is increased, so that the pressure in the left control chamber is less than that in the right control chamber. The pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the valve seat return spring (10) on the valve seat (7), drives the load valve core (5) to drive the valve seat (7) to move synchronously to the left. The pressure difference between the left control chamber and the right control chamber overcomes the elastic force of the return spring (9) and the valve seat return spring (10), drives the load valve core (5) to drive the valve seat (7) and the return valve core (8) to move synchronously to the left, and causes the right end of the return valve core (8) to move synchronously to the left. The surface is separated from the left side of the shoulder on the inner side of the shell, the return liquid flow channel is connected, the return liquid T port (2.1), the return liquid flow channel, the return liquid cavity, the inner cavity of the valve seat (7), the inner cavity of the load valve core (5) and the load end A port (3.1) are connected, so that the proportional valve is switched to the AT working position, and the return liquid T port (2.1) is connected with the load end A port (3.1); in the AT working position, the pressure of the left control cavity K1 port (2.3) is adjusted according to the target flow until the flow of liquid flowing out of the return liquid T port (2.1) reaches the target flow.

Images