High-water-base large-flow digital proportional valve

Abstract

The invention relates to the technical field of hydraulic valves, and discloses a high-water-base large-flow digital proportional valve which comprises a valve seat unit. By adjusting the pressure of the control cavity K1 and the pressure of the control cavity K2, a certain pressure difference is formed between high-water-base hydraulic media in the control cavity K1 and the control cavity K2, so that the high-water-base hydraulic media can push a low-pressure side pushing check ring or a high-pressure side pushing check ring to move, the low-pressure side pushing check ring or the high-pressure side pushing check ring can drive a push rod to move, and the low-pressure side pushing check ring or the high-pressure side pushing check ring can push the high-pressure side pushing check ring to move. Therefore, the high-pressure side cone valve element or the low-pressure side cone valve element can be driven to move synchronously, when the high-pressure side cone valve element moves, the high-pressure side cone valve element can be matched with a reset spring to press the low-pressure side cone valve element, and when the low-pressure side cone valve element moves, the low-pressure side cone valve element can be matched with the reset spring to press the high-pressure side cone valve element. Due to the fact that the push rod is in separated drive with the high-pressure side cone valve element and the low-pressure side cone valve element, the three-position three-way O-shaped full-proportion control valve with the meso-position function is achieved, accuracy of flow control is guaranteed, and hydraulic impact is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic valves, in particular to a high-water-base large-flow digital proportional valve. Background Art

[0002] High-pressure, high-flow, high-water-based electro-hydraulic reversing valves are the core components of underground fully-mechanized mining in coal mines. However, due to issues such as explosion-proof safety and environmental protection, mine hydraulic systems generally use high-water-based emulsions as transmission media. This high-water-based medium has the characteristics of low viscosity and easy leakage. Therefore, a switch-type electro-hydraulic reversing valve in the form of a cone valve is mainly used for flow control, which has problems such as large hydraulic shock, poor control accuracy, and component damage. It is also difficult to meet the precise control of the flow during fine-tuning actions. Therefore, there is an urgent need for a high-water-based reversing valve that can achieve flow ratio regulation.

[0003] At present, Chinese patent CN109555740A discloses a water-based proportional valve for hydraulic support electro-hydraulic control system, which adopts DC servo motor for control to realize proportional control of main reversing valve, but the structure of the invention is relatively complex, and can only realize proportional control of high-pressure water inlet chamber P→working chamber A, while working chamber A→return water chamber T is still switch control, and needs the assistance of two-position two-way switch valve; Chinese patent CN115653961A discloses a high water-based proportional directional valve, which realizes proportional control of reversing valve by driving independent double valve core three-way valve structure through double voice coil motor, but has no O-type neutral position function, and has more sliding seals, large running resistance, and reduced dynamic performance of valve core. Therefore, developing a high water-based large flow digital proportional valve with low leakage, high dynamic and high reliability with O-type neutral position function is a technical problem that needs to be solved in the field of mining hydraulic valves.

[0004] Currently, no effective solution has been proposed for the problems in the related technologies. Summary of the invention

[0005] 1. Technical issues to be solved

[0006] In view of the shortcomings of the prior art, the present invention provides a high-water-base, large-flow digital proportional valve, which has a push rod and a high-pressure side cone valve core and a low-pressure side cone valve core that are driven separately, thereby realizing a three-position, three-way, O-type, neutral-position fully proportional control valve, ensuring the accuracy of flow control, avoiding hydraulic shock and other advantages, and solving the problems of more sliding seals, greater operating resistance, and reduced dynamic performance of the valve core.

[0007] (II) Technical solution

[0008] In order to solve the above-mentioned technical problems of too many sliding seals, large running resistance and reduced dynamic performance of the valve core, the present invention provides the following technical solutions:

[0009] A high water-based large flow digital proportional valve, comprising a valve seat unit:

[0010] The valve seat unit is respectively provided with a pilot unit and a main reversing valve unit;

[0011] The valve seat unit includes a main valve body, one end of which is fixedly connected to a pilot unit, a valve sleeve is provided on the main reversing valve unit, and the valve sleeve is concentrically matched with the inner hole of the main valve body. A push rod is provided inside the main reversing valve unit, and the control chamber K1 and the control chamber K2 of the pilot unit act on both sides of the push rod respectively, so that the pressure of the control chamber K1 and the control chamber K2 of the pilot unit drives the push rod to move, so as to control the direction and flow rate of the high water-based hydraulic medium;

[0012] The main reversing valve unit includes a right bushing, which is concentrically matched with the inner hole of the valve sleeve. A cover plate is provided at the right end of the right bushing, and the right bushing is fixedly connected to the main valve body through the cover plate. The cover plate presses the right end surface of the valve sleeve and the right bushing to complete the fixation of the valve sleeve and the right bushing. The left side of the push rod is concentrically matched with the inner hole of the valve sleeve to form a control chamber K1, and the right side of the push rod is concentrically matched with the inner hole of the right bushing to form a control chamber K2. The outer circle of the left section of the push rod is sequentially sleeved with a low-pressure side push ring, a low-pressure side push ring, and a low-pressure side push ring. The pressure side cone valve core, the return spring, the high-pressure side cone valve core and the high-pressure side push ring, the left end of the low-pressure side cone valve core is a frustoconical structure, and the right end is a cylindrical structure, the left conical surface of the low-pressure side cone valve core cooperates with the step surface of the valve sleeve, which is the conical sealing surface of the working chamber → the return water chamber, the right end surface of the low-pressure side cone valve core cooperates with the plane of the return spring, and the spring force of the return spring acts on the right end surface of the low-pressure side cone valve core, so that the low-pressure side cone valve core can be reliably pressed against the step surface of the valve sleeve to ensure that the working chamber → the return water chamber forms a reliable conical seal with extremely low leakage;

[0013] The high-pressure side cone valve core is a cone-shaped structure as a whole. The right side cone surface of the high-pressure side cone valve core cooperates with the left step surface of the right bushing to form a cone sealing surface of the high-pressure water inlet chamber→working chamber. The left end surface of the high-pressure side cone valve core cooperates with the plane of the return spring so that the spring force of the return spring acts on the left end surface of the high-pressure side cone valve core, so that the high-pressure side cone valve core is reliably pressed against the step surface of the right bushing, so as to ensure that the high-pressure water inlet chamber→working chamber forms a reliable cone seal with extremely low leakage;

[0014] When the pressure of the control chamber K1 and the control chamber K2 are adjusted, the push rod is moved by the pressure difference on both sides, and the push rod is pushed by the low-pressure side push ring or the high-pressure side push ring to realize the synchronous movement of the high-pressure side cone valve core or the low-pressure side cone valve core, so that the other side cone valve core is tightened, and the opening of the cone valve port is proportional to the displacement of the push rod, thereby realizing proportional control of the flow rate and flow direction of the main reversing valve, so as to accurately control the position of the push rod and realize accurate proportional control of the opening of the cone valve. The main reversing valve is a three-position, three-way, O-type, mid-position functional cone valve, which is used for full proportional flow control of the cone valve structure.

[0015] Preferably, the push rod is a two-section concentric cylinder, the left section of the push rod is provided with a pressure equalizing groove, the control chamber K1 is connected with the pilot pressure chamber through the internal channel of the push rod, so that the pilot pressure chamber is connected with the pilot unit control valve group, the right end of the push rod is slidably matched with the inner hole of the right bushing, and the outer surface of the right end of the push rod is provided with a pressure equalizing groove, so that the push rod can reciprocate along the axis of the right bushing, so as to reduce the hydraulic clamping force and prevent the valve core from being biased;

[0016] The control chamber K2 is connected to the pilot unit control valve group through a channel, and the orderly high-frequency on-off of the four high-speed switch valves in the pilot unit is controlled to sensitively and quickly adjust the pressures of the control chamber K1 and the control chamber K2, so that the pressure difference formed by the control chamber K1 and the control chamber K2 acts on both sides of the push rod to generate an axial thrust on the push rod and make the push rod move axially. The pilot control unit can also adopt other pilot drive methods to adjust the pressures of the control chamber K1 and the control chamber K2.

[0017] Preferably, the low-pressure side push-retaining ring and the high-pressure side push-retaining ring are respectively fixedly assembled in the groove of the left section cylinder of the push rod, so that the low-pressure side push-retaining ring and the high-pressure side push-retaining ring follow the push rod to move axially, the low-pressure side push-retaining ring cooperates with the left end face of the low-pressure side cone valve core, and the high-pressure side push-retaining ring cooperates with the right end face of the high-pressure side cone valve core;

[0018] The left side cone table surface of the high-pressure side cone valve core is the sealing cone surface of the high-pressure water inlet chamber→working chamber. The right side outer cylindrical surface of the high-pressure side cone valve core is concentrically matched with the inner hole of the right bushing, so that the high-pressure side cone valve core balances the thrust generated by the high-pressure water source on the left side cone table surface and the thrust generated by the high-pressure water source on the right side step surface, so as to avoid the high-pressure side cone valve core being opened by the pressure of the high-pressure water source. The chamber formed by the right end of the high-pressure side cone valve core and the push rod is a low-pressure chamber, and the low-pressure chamber is connected with the return water chamber through the internal channel of the push rod, so as to avoid vacuum or pressure holding inside the low-pressure chamber.

[0019] Preferably, the pilot unit includes a high-speed switching valve and a cover plate, and four groups of two-position two-way high-speed switching valves are used to form a pilot unit control valve group. The pilot unit control valve group is plugged and fixed to the right end face of the cover plate, and a channel is opened inside the cover plate so that the channel and the high-speed switching valve form a hydraulic full-bridge circuit, and the orderly high-frequency switching of the four groups of high-speed switching valves is controlled so that the two pilot control oil circuits enter the control chamber K1 and the control chamber K2 respectively, so as to realize the rapid control of the internal pressure of the control chamber K1 and the control chamber K2. The cover plate is connected to the main valve body by bolts, and the end face between the cover plate and the main valve body is provided with a static sealing ring for sealing.

[0020] Preferably, the valve seat unit includes a main valve body, an LVDT core and an LVDT shell. The main valve body is designed in a valve seat shape. A high-pressure water inlet chamber, a return water chamber and a working chamber are provided inside the main valve body. The high-pressure water inlet chamber is connected to the system pressure source, the return water chamber is connected to the return water tank, and the working chamber is connected to the working chamber. A valve hole that is assembled with the valve sleeve is provided inside the main valve body to realize the connection between the main reversing valve unit and the valve seat unit. The right end face of the main valve body is matched with the end face of the cover plate and is connected by screws to realize the connection between the pilot unit and the valve seat unit. The LVDT core is connected to the push rod through a thread, and the LVDT shell is fixedly connected to the main valve body through a thread. The LVDT core moves synchronously with the push rod, and the axial displacement of the push rod is quickly and accurately fed back by the LVDT core. Other sensors that can provide feedback signals for closed-loop control of the main valve core position can also be used.

[0021] Preferably, the high-pressure side cone valve core, the low-pressure side cone valve core and the push rod are concentrically matched, and there is a relative displacement between the high-pressure side cone valve core, the low-pressure side cone valve core and the push rod, and the inner matching surfaces of the high-pressure side cone valve core, the low-pressure side cone valve core and the push rod are provided with sliding sealing rings to achieve sealing between the working chamber and the high-pressure water inlet chamber and the return water chamber.

[0022] (III) Beneficial effects

[0023] Compared with the prior art, the present invention provides a high water-base large flow digital proportional valve, which has the following beneficial effects:

[0024] 1. The present invention adjusts the pressure of the control chamber K1 and the control chamber K2 to form a certain pressure difference between the high-water-based hydraulic medium in the control chamber K1 and the control chamber K2, so that the high-water-based hydraulic medium can push the low-pressure side push retaining ring or the high-pressure side push retaining ring to move, so that it can drive the push rod to move, thereby driving the high-pressure side cone valve core or the low-pressure side cone valve core to move synchronously, and then when the high-pressure side cone valve core moves, it can cooperate with the return spring to press the low-pressure side cone valve core, and when the low-pressure side cone valve core moves, it can cooperate with the return spring to press the high-pressure side cone valve core. Since the push rod and the high-pressure side cone valve core and the low-pressure side cone valve core are driven separately, a three-position three-way O-type neutral function full-proportional control valve is realized, thereby ensuring the accuracy of flow control and avoiding hydraulic shock.

[0025] 2. The present invention arranges the right outer cylindrical surface of the high-pressure side cone valve core concentrically with the inner hole of the right bushing, and the high-pressure side cone valve core can balance the thrust of the high-pressure water source on the left cone table surface and the thrust of the high-pressure water source on the right step surface, thereby preventing the high-pressure side cone valve core from opening due to the pressure of the high-pressure water source, thereby ensuring that the valve core is subjected to balanced force while ensuring extremely low leakage.

[0026] 3. The present invention arranges multiple sets of sliding sealing rings between the push rod, the high-pressure side cone valve core and the low-pressure side cone valve core respectively, so as to seal the push rod, the high-pressure side cone valve core and the low-pressure side cone valve core, thereby ensuring the high dynamic, high reliability and low leakage characteristics of the reversing valve core.

[0027] 4. The present invention controls the valve group through a pilot unit to perform orderly high-frequency switching, so that the two high-speed switch valves therein respectively control the oil circuits to enter the control chamber K1 and the control chamber K2, thereby being able to perform high-frequency and precise control of the internal pressures of the control chamber K1 and the control chamber K2, and having the advantages of flexible control, high control accuracy and fast response. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the proportional valve structure of the present invention;

[0029] Figure 2 It is a schematic diagram of the overall appearance of the digital proportional valve of the present invention;

[0030] Figure 3 This is a schematic diagram of a three-position three-way digital proportional valve of the present invention;

[0031] Figure 4 This is a schematic diagram of the fully proportional control drive principle of the three-position three-way cone valve of the present invention.

[0032] In the figure: 1. high-speed switching valve; 2. cover plate; 3. valve sleeve; 4. right bushing; 5. static sealing ring; 6. high-pressure side cone valve core; 7. low-pressure side cone valve core; 8. main valve body; 9. LVDT core; 10. LVDT housing; 11. low-pressure side push and retaining ring; 12. return spring; 13. sliding sealing ring; 14. high-pressure side push and retaining ring; 15. push rod; P, high-pressure water inlet chamber; A, working chamber; T, return water chamber; b, pilot pressure chamber; c, control chamber K1; d, low-pressure chamber; e, control chamber K2. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] As introduced in the background technology, there are deficiencies in the prior art. In order to solve the above technical problems, this application proposes a high water-based large flow digital proportional valve.

[0035] Embodiment 1:

[0036] See also Figure 1 and Figure 2 , a high water-based large flow digital proportional valve, comprising a valve seat unit:

[0037] The valve seat unit is respectively provided with a pilot unit and a main reversing valve unit;

[0038] The valve seat unit includes a main valve body 8, one end of which is fixedly connected to the pilot unit. A valve sleeve 3 is provided on the main reversing valve unit, and the valve sleeve 3 is concentrically matched with the inner hole of the main valve body 8. A push rod 15 is provided inside the main reversing valve unit. The control chamber K1c and the control chamber K2e of the pilot unit act on both sides of the push rod 15 respectively, so that the pressure of the control chamber K1c and the control chamber K2e of the pilot unit drives the push rod to move, so as to control the direction and flow size of the high water-based hydraulic medium.

[0039] The main reversing valve unit includes a right bushing 4, which is concentrically matched with the inner hole of the valve sleeve 3. A cover plate 2 is provided at the right end of the right bushing 4. The right bushing 4 is fixedly connected to the main valve body 8 through the cover plate 2. The cover plate 2 presses the right end surface of the valve sleeve 3 and the right bushing 4 to complete the fixation of the valve sleeve 3 and the right bushing 4. The left side of the push rod 15 is concentrically matched with the inner hole of the valve sleeve 3 to form a control chamber K1. c, and the right side of the push rod 15 is concentrically matched with the inner hole of the right bushing 4 to form a control chamber K2e. The outer circle of the left section of the push rod 15 is sleeved with a low-pressure side push and retaining ring 11, a low-pressure side cone valve core 7, a return spring 12, a high-pressure side cone valve core and a high-pressure side push and retaining ring 14 from the left end to the right end. The left end of the low-pressure side cone valve core 7 is a frustum-shaped structure, and the right end is a cylindrical structure. The left conical surface of the low-pressure side cone valve core 7 is matched with the step surface of the valve sleeve 3 to form a conical sealing surface of the working chamber A→return chamber T. The right end surface of the low-pressure side cone valve core 7 is matched with the plane of the return spring 12. The spring force of the return spring 12 acts on the right end surface of the low-pressure side cone valve core 7, so that the low-pressure side cone valve core 7 is reliably pressed against the step surface of the valve sleeve 3 to ensure that the working chamber A→return chamber T forms a reliable conical seal with extremely low leakage;

[0040] The high-pressure side cone valve core 6 is a cone-shaped structure as a whole. The right cone surface of the high-pressure side cone valve core 6 cooperates with the left step surface of the right bushing 4 to form a conical sealing surface of the high-pressure water inlet chamber P→working chamber A. The left end surface of the high-pressure side cone valve core 6 cooperates with the plane of the return spring 12, so that the spring force of the return spring 12 acts on the left end surface of the high-pressure side cone valve core 6, so that the high-pressure side cone valve core 6 is reliably pressed against the step surface of the right bushing 4, so as to ensure that the high-pressure water inlet chamber P→working chamber A forms a reliable conical seal with extremely low leakage;

[0041] When the pressure of the control chamber K1c and the control chamber K2e are adjusted, the push rod 15 is moved by the pressure difference on both sides. The push rod 15 is pushed by the low-pressure side push and retaining ring 11 or the high-pressure side push and retaining ring 14 to realize the synchronous movement of the high-pressure side cone valve core 6 or the low-pressure side cone valve core 7, so that the other side cone valve core is compressed. The opening of the cone valve port is proportional to the displacement of the push rod 15, realizing the proportional control of the flow rate of the main reversing valve and the flow direction control, so as to accurately control the position of the push rod 15 and realize the precise proportional control of the opening of the cone valve. The main reversing valve is a three-position three-way O-type center-function cone valve, which is used for the full proportional flow control of the cone valve structure.

[0042] When in use, by adjusting the pressure of the control chamber K1c and the control chamber K2e, since the control chamber K1c and the control chamber K2e are respectively located on both sides of the push rod 15, and the pressure of the high-water-based hydraulic medium inside the control chamber K1c and the control chamber K2e can be adjusted, a certain pressure difference is formed between the high-water-based hydraulic medium inside the control chamber K1c and the control chamber K2e, so that the high-water-based hydraulic medium can push the low-pressure side push and retaining ring 11 or the high-pressure side push and retaining ring 14 to move, so that it can drive the push rod 15 to move, thereby enabling it to drive the high-pressure side cone valve core 6 or the low-pressure side cone valve core 7 to move synchronously, and then when the high-pressure side cone valve core 6 moves, it can cooperate with the return spring 12 to press the low-pressure side cone valve core 7, and when the low-pressure side cone valve core 7 moves, it can cooperate with the return spring 12 to press the high-pressure side cone valve core 6, and since the opening of the cone valve port is proportional to the displacement of the push rod 15, the flow rate of the main reversing valve can be proportionally controlled and the flow direction can be controlled.

[0043] The present invention adjusts the pressure of the control chamber K1c and the control chamber K2e to form a certain pressure difference between the high-water-based hydraulic medium inside the control chamber K1c and the control chamber K2e, so that the high-water-based hydraulic medium can push the low-pressure side push and retaining ring 11 or the high-pressure side push and retaining ring 14 to move, so that it can drive the push rod 15 to move, thereby enabling it to drive the high-pressure side cone valve core 6 or the low-pressure side cone valve core 7 to move synchronously, and then when the high-pressure side cone valve core 6 moves, it can cooperate with the return spring 12 to press the low-pressure side cone valve core 7, and when the low-pressure side cone valve core 7 moves, it can cooperate with the return spring 12 to press the high-pressure side cone valve core 6. Since the push rod 15 and the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are driven separately, a three-position three-way O-type neutral function full-proportional control valve is realized, thereby ensuring the accuracy of flow control and avoiding hydraulic shock.

[0044] Embodiment 2:

[0045] The difference from the above embodiment is that, see Figure 1 and Figure 4 The push rod 15 is a two-section concentric cylinder. The left section of the push rod 15 is provided with a pressure equalizing groove. The control chamber K1c is connected with the pilot pressure chamber b through the internal channel of the push rod 15, so that the pilot pressure chamber b is connected with the pilot unit control valve group. The right end of the push rod 15 is slidably matched with the inner hole of the right bushing 4, and the outer surface of the right end of the push rod 15 is provided with a pressure equalizing groove, so that the push rod 15 can reciprocate along the axis of the right bushing 4 to reduce the hydraulic clamping force and prevent the valve core from being biased.

[0046] The control chamber K2e is connected to the pilot unit control valve group through the orifice, and the pressures of the control chamber K1c and the control chamber K2e are sensitively and quickly adjusted by controlling the orderly high-frequency on-off of the four high-speed switch valves 1 in the pilot unit, so that the pressure difference formed by the control chamber K1c and the control chamber K2e acts on both sides of the push rod 15, so as to generate an axial thrust on the push rod 15 and make the push rod 15 move axially. The pilot control unit can also adopt other pilot drive modes to adjust the pressures of the control chamber K1c and the control chamber K2e.

[0047] By controlling the orderly high-frequency on-off of the four high-speed switch valves 1 in the pilot unit, the internal pressures of the control chamber K1c and the control chamber K2e can be adjusted to form a pressure difference between the control chamber K1c and the control chamber K2e. Since the control chamber K1c is connected to the pilot pressure chamber b through the internal channel of the push rod 15, and the pilot pressure chamber b is connected to the pilot unit control valve group, the pressure difference between the control chamber K1c and the control chamber K2e can push the push rod 15 to move axially, so as to accurately control the movement of the push rod 15.

[0048] Embodiment three:

[0049] The difference from the above embodiment is that, see Figure 1 The low-pressure side push-retaining ring 11 and the high-pressure side push-retaining ring 14 are respectively fixedly assembled in the groove of the left cylindrical part of the push rod 15, so that the low-pressure side push-retaining ring 11 and the high-pressure side push-retaining ring 14 follow the push rod 15 to move axially, the low-pressure side push-retaining ring 11 cooperates with the left end surface of the low-pressure side cone valve core 7, and the high-pressure side push-retaining ring 14 cooperates with the right end surface of the high-pressure side cone valve core 6;

[0050] The left side cone table surface of the high-pressure side cone valve core 6 is the sealing cone surface of the high-pressure water inlet chamber P→working chamber A. The right side outer cylindrical surface of the high-pressure side cone valve core 6 is concentrically matched with the inner hole of the right bushing 4, so that the high-pressure side cone valve core 6 can balance the thrust generated by the high-pressure water source on the left side cone table surface and the thrust generated by the high-pressure water source on the right side step surface, so as to avoid the high-pressure side cone valve core 6 from being opened by the pressure of the high-pressure water source. The chamber formed by the right end of the high-pressure side cone valve core 6 and the push rod 15 is the low-pressure chamber d, and the low-pressure chamber d is connected with the return chamber T through the internal channel of the push rod 15, so as to avoid vacuum or pressure holding inside the low-pressure chamber d.

[0051] Since both the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are cone-surface structures, the forces on the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 can be more balanced. Since the right outer cylindrical surface of the high-pressure side cone valve core 6 is concentrically arranged with the inner hole of the right bushing 4, and the high-pressure side cone valve core 6 can balance the thrust of the high-pressure water source on the left cone table surface and the thrust of the high-pressure water source on the right step surface, the high-pressure side cone valve core 6 can be prevented from being opened by the pressure of the high-pressure water source, thereby ensuring that the valve core is under balanced force while ensuring extremely low leakage.

[0052] Embodiment 4:

[0053] The difference from the above embodiment is that, see Figure 1 and Figure 4 The pilot unit includes a high-speed switch valve 1 and a cover plate 2. Four groups of two-position two-way high-speed switch valves 1 are used to form a pilot unit control valve group. The pilot unit control valve group is plugged and fixed to the right end surface of the cover plate 2. A hole is opened inside the cover plate 2 so that the hole and the high-speed switch valve 1 form a hydraulic full-bridge circuit to control the orderly high-frequency switching of the four groups of high-speed switch valves 1 so that the two pilot control oil circuits enter the control chamber K1c and the control chamber K2e respectively, so as to realize the rapid control of the internal pressure of the control chamber K1c and the control chamber K2e. The cover plate 2 is connected to the main valve body 8 by bolts, and the end surface between the cover plate 2 and the main valve body 8 is provided with a static sealing ring 5 for sealing.

[0054] The pilot unit controls the valve group to perform orderly high-frequency on-off, so that the two high-speed switch valves 1 respectively control the oil circuit to enter the control chamber K1c and the control chamber K2e, thereby enabling high-frequency and precise control of the internal pressure of the control chamber K1c and the control chamber K2e, which has the advantages of flexible control, high control accuracy and fast response.

[0055] Embodiment five:

[0056] The difference from the above embodiment is that, see Figure 1 The valve seat unit includes a main valve body 8, an LVDT core 9 and an LVDT housing 10. The main valve body 8 is designed in a valve seat shape. A high-pressure water inlet chamber P, a return water chamber T and a working chamber A are provided inside the main valve body 8. The high-pressure water inlet chamber P is connected to the system pressure source, the return water chamber T is connected to the return water tank, and the working chamber A is connected to the working chamber. A valve hole that is assembled with the valve sleeve 3 is provided inside the main valve body 8 to realize the connection between the main reversing valve unit and the valve seat unit. The right end face of the main valve body 8 is matched with the end face of the cover plate 2 and is connected by screws to realize the connection between the pilot unit and the valve seat unit. The LVDT core 9 is connected to the push rod 15 by threads, and the LVDT housing 10 is fixedly connected to the main valve body 8 by threads. The LVDT core 9 moves synchronously with the push rod 15, and the axial displacement of the push rod 15 is quickly and accurately fed back by the LVDT core 9. Other sensors that can provide feedback signals for the closed-loop control of the main valve core position can also be used.

[0057] Since the LVDT core 9 is threadedly connected to the push rod 15, and the LVDT core 9 can move synchronously with the movement of the push rod 15, the LVDT core 9 can quickly and accurately feed back the movement data of the push rod 15 to the sensor, thereby detecting the movement state of the push rod 15 in real time to determine the real-time data of the high-water-base large-flow digital proportional valve for adjustment thereof.

[0058] Embodiment six:

[0059] The difference from the above embodiment is that, see Figure 1 The high-pressure side cone valve core 6, the low-pressure side cone valve core 7 and the push rod 15 are concentrically matched, and there is a relative displacement between the high-pressure side cone valve core 6, the low-pressure side cone valve core 7 and the push rod 15. The inner matching surfaces of the high-pressure side cone valve core 6, the low-pressure side cone valve core 7 and the push rod 15 are provided with a sliding sealing ring 13 to achieve the sealing of the working chamber A with the high-pressure water inlet chamber P and the return water chamber T.

[0060] Since three groups of sliding sealing rings 13 are provided and respectively located between the push rod 15, the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7, the push rod 15, the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are sealed to ensure the high dynamic, high reliability and low leakage characteristics of the reversing valve core.

[0061] Working principle: When in use, when the push rod 15 is subjected to the combined thrust to the left and moves to the left, the high-pressure side push and retaining ring 14 overcomes the spring force of the return spring 12 and the hydraulic force in the valve, and pushes the high-pressure side cone valve core 6 to move to the left synchronously, opening the opening of the high-pressure water inlet chamber P→working chamber A, while the low-pressure side push and retaining ring 11 is disengaged from the low-pressure side cone valve core 7, and the low-pressure side cone valve core 7 is reliably pressed against the step surface of the valve sleeve 3 by the spring force, ensuring reliable sealing of the working chamber A→return chamber T;

[0062] Similarly, when the push rod 15 is moved rightward by the combined thrust to the right, the low-pressure side push-retainer ring 11 overcomes the spring force of the return spring 12 and the hydraulic force in the valve, and pushes the low-pressure side cone valve core 7 to move rightward synchronously, opening the opening of the working chamber A→the return chamber T, while the high-pressure side push-retainer ring 14 is disengaged from the high-pressure side cone valve core 6, and the high-pressure side cone valve core 6 is reliably pressed against the step surface of the right bushing 4 by the spring force, ensuring that the high-pressure water inlet chamber P→the working chamber A is reliably sealed;

[0063] When the push rod 15 is kept in the middle position, both the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are acted upon by the spring force and are reliably pressed against the step surface to achieve reliable sealing.

[0064] Through the above technical scheme, 1. By adjusting the pressure of the control chamber K1c and the control chamber K2e, a certain pressure difference is formed between the high-water-based hydraulic medium in the control chamber K1c and the control chamber K2e, so that the high-water-based hydraulic medium can push the low-pressure side push-retaining ring 11 or the high-pressure side push-retaining ring 14 to move, so that it can drive the push rod 15 to move, thereby enabling it to drive the high-pressure side cone valve core 6 or the low-pressure side cone valve core 7 to move synchronously, and then when the high-pressure side cone valve core 6 moves, it can cooperate with the return spring 12 to press the low-pressure side cone valve core 7, and when the low-pressure side cone valve core 7 moves, it can cooperate with the return spring 12 to press the high-pressure side cone valve core 6. Since the push rod 15 and the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are driven separately, a three-position three-way O-type mid-position full-proportional control valve is realized, which ensures the accuracy of flow control and avoids hydraulic shock.

[0065] 2. By setting the right outer cylindrical surface of the high-pressure side cone valve core 6 concentrically with the inner hole of the right bushing 4, the high-pressure side cone valve core 6 can balance the thrust of the high-pressure water source on the left cone table surface and the thrust of the high-pressure water source on the right step surface, thereby preventing the high-pressure side cone valve core 6 from being opened by the pressure of the high-pressure water source, thereby ensuring that the valve core is balanced in force and extremely low leakage is guaranteed;

[0066] 3. By arranging multiple sets of sliding sealing rings 13 between the push rod 15, the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7, the push rod 15, the high-pressure side cone valve core 6 and the low-pressure side cone valve core 7 are sealed to ensure the high dynamic, high reliability and low leakage characteristics of the reversing valve core;

[0067] 4. The pilot unit controls the valve group to perform orderly high-frequency on-off, so that the two high-speed switch valves 1 respectively control the oil circuit to enter the control chamber K1c and the control chamber K2e, thereby enabling high-frequency and precise control of the internal pressure of the control chamber K1c and the control chamber K2e, which has the advantages of flexible control, high control accuracy and fast response.

[0068] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A high water-based large flow digital proportional valve, comprising a valve seat unit, characterized in that: The valve seat unit is respectively provided with a pilot unit and a main reversing valve unit; The valve seat unit comprises a main valve body (8), one end of which is fixedly connected to a pilot unit, a valve sleeve (3) is arranged on the main reversing valve unit, the valve sleeve (3) is concentrically matched with the inner hole of the main valve body (8), a push rod (15) is arranged inside the main reversing valve unit, and a control chamber K1 (c) and a control chamber K2 (e) of the pilot unit act on two sides of the push rod (15) respectively, so that the pressure of the control chamber K1 (c) and the control chamber K2 (e) of the pilot unit drives the push rod to move, so as to control the direction and flow rate of the high water-based hydraulic medium; The main reversing valve unit comprises a right bushing (4), the right bushing (4) is coaxially matched with the inner hole of the valve sleeve (3), a cover plate (2) is arranged at the right end of the right bushing (4), the right bushing (4) is fixedly connected with the main valve body (8) through the cover plate (2), the cover plate (2) presses the right end surface of the valve sleeve (3) and the right bushing (4) to complete the fixation of the valve sleeve (3) and the right bushing (4), the left side of the push rod (15) is coaxially matched with the inner hole of the valve sleeve (3) to form a control chamber K1 (c), and the right side of the push rod (15) is coaxially matched with the inner hole of the right bushing (4) to form a control chamber K2 (e), and the outer circle of the left section of the push rod (15) is sequentially sleeved with low-pressure side push blocks from the left end to the right end. The low-pressure side cone valve core (7) is provided with a ring (11), a low-pressure side cone valve core (7), a return spring (12), a high-pressure side cone valve core and a high-pressure side push-retaining ring (14), wherein the left end of the low-pressure side cone valve core (7) is a cone-shaped structure, and the right end is a cylindrical structure. The left cone surface of the low-pressure side cone valve core (7) cooperates with the step surface of the valve sleeve (3) to form a cone sealing surface from the working chamber (A) to the return chamber (T). The right end surface of the low-pressure side cone valve core (7) cooperates with the plane of the return spring (12). The spring force of the return spring (12) acts on the right end surface of the low-pressure side cone valve core (7), so that the low-pressure side cone valve core (7) can be reliably pressed against the step surface of the valve sleeve (3) to ensure that the working chamber (A) → the return chamber (T) forms a reliable cone seal with extremely low leakage; The high-pressure side cone valve core (6) is a cone-shaped structure as a whole. The right cone surface of the high-pressure side cone valve core (6) cooperates with the left step surface of the right bushing (4) to form a cone sealing surface from the high-pressure water inlet chamber (P) to the working chamber (A). The left end surface of the high-pressure side cone valve core (6) cooperates with the plane of the return spring (12) so that the spring force of the return spring (12) acts on the left end surface of the high-pressure side cone valve core (6), so that the high-pressure side cone valve core (6) can be reliably pressed against the step surface of the right bushing (4), so as to ensure that the high-pressure water inlet chamber (P) → the working chamber (A) forms a reliable cone seal with extremely low leakage; When the pressure of the control chamber K1 (c) and the control chamber K2 (e) are adjusted, the push rod (15) is moved by the pressure difference on both sides. The push rod (15) is pushed by the low-pressure side push ring (11) or the high-pressure side push ring (14) to achieve synchronous movement of the high-pressure side cone valve core (6) or the low-pressure side cone valve core (7), so that the cone valve core on the other side is compressed. The opening of the cone valve port is proportional to the displacement of the push rod (15), thereby achieving proportional control of the flow rate and flow direction of the main reversing valve, so as to accurately control the position of the push rod (15) and achieve accurate proportional control of the opening of the cone valve. The main reversing valve is a three-position three-way O-type center-function cone valve, which is used for full proportional flow control of the cone valve structure.

2. A high water base large flow digital proportional valve according to claim 1, characterized in that: The push rod (15) is a two-section concentric cylinder. The left section of the push rod (15) is provided with a pressure equalizing groove. The control chamber K1 (c) is connected with the pilot pressure chamber (b) through the internal channel of the push rod (15), so that the pilot pressure chamber (b) is connected with the pilot unit control valve group. The right end of the push rod (15) is slidably matched with the inner hole of the right bushing (4), and the outer surface of the right end of the push rod (15) is provided with a pressure equalizing groove, so that the push rod (15) can move back and forth along the axis of the right bushing (4) to reduce the hydraulic clamping force and prevent the valve core from being biased. The control chamber K2(e) is connected to the pilot unit control valve group through a channel, and the pressure of the control chamber K1(c) and the control chamber K2(e) is sensitively and quickly adjusted by controlling the orderly high-frequency on and off of the four high-speed switch valves (1) in the pilot unit, so that the pressure difference formed by the control chamber K1(c) and the control chamber K2(e) acts on both sides of the push rod (15) to generate an axial thrust on the push rod (15) and make the push rod (15) move axially. The pilot control unit can also adopt other pilot drive methods to adjust the pressure of the control chamber K1(c) and the control chamber K2(e).

3. A high water base large flow digital proportional valve according to claim 1, characterized in that: The low-pressure side thrust ring (11) and the high-pressure side thrust ring (14) are respectively fixedly assembled in the groove of the left cylindrical section of the push rod (15), so that the low-pressure side thrust ring (11) and the high-pressure side thrust ring (14) follow the push rod (15) to move axially, the low-pressure side thrust ring (11) cooperates with the left end surface of the low-pressure side cone valve core (7), and the high-pressure side thrust ring (14) cooperates with the right end surface of the high-pressure side cone valve core (6); The left cone surface of the high-pressure side cone valve core (6) is a sealing cone surface of the high-pressure water inlet chamber (P) → working chamber (A). The right outer cylindrical surface of the high-pressure side cone valve core (6) is concentrically matched with the inner hole of the right bushing (4), so that the high-pressure side cone valve core (6) can balance the thrust generated by the high-pressure water source on the left cone surface and the thrust generated by the high-pressure water source on the right step surface, so as to prevent the high-pressure side cone valve core (6) from opening due to the pressure of the high-pressure water source. The chamber formed by the right end of the high-pressure side cone valve core (6) and the push rod (15) is a low-pressure chamber (d). The low-pressure chamber (d) is connected to the return water chamber (T) through the internal channel of the push rod (15), so as to prevent the low-pressure chamber (d) from being sucked in or blocked.

4. A high water base large flow digital proportional valve according to claim 1, characterized in that: The pilot unit comprises a high-speed switch valve (1) and a cover plate (2). Four groups of two-position two-way high-speed switch valves (1) are used to form a pilot unit control valve group. The pilot unit control valve group is plugged and fixed to the right end face of the cover plate (2). A hole is provided inside the cover plate (2) so that the hole and the high-speed switch valve (1) form a hydraulic full-bridge circuit to control the orderly high-frequency switching of the four groups of high-speed switch valves (1) so that two pilot control oil circuits enter the control chamber K1 (c) and the control chamber K2 (e) respectively, so as to realize the rapid control of the internal pressure of the control chamber K1 (c) and the control chamber K2 (e). The cover plate (2) is connected to the main valve body (8) by bolts, and the end face between the cover plate (2) and the main valve body (8) is provided with a static sealing ring (5) for sealing.

5. A high water base large flow digital proportional valve according to claim 1, characterized in that: The valve seat unit comprises a main valve body (8), an LVDT core (9) and an LVDT housing (10); the main valve body (8) is designed in the shape of a valve seat; a high-pressure water inlet chamber (P), a return water chamber (T) and a working chamber (A) are provided inside the main valve body (8); the high-pressure water inlet chamber (P) is connected to a system pressure source; the return water chamber (T) is connected to a return water tank; the working chamber (A) is connected to the working chamber; a valve hole is provided inside the main valve body (8) to be assembled with the valve sleeve (3) so as to realize the connection between the main reversing valve unit and the valve seat unit; The right end face of the main valve body (8) cooperates with the end face of the cover plate (2) and is connected by screws to realize the connection between the pilot unit and the valve seat unit. The LVDT core (9) is connected to the push rod (15) by threads. The LVDT housing (10) is fixedly connected to the main valve body (8) by threads. The LVDT core (9) moves synchronously with the push rod (15). The LVDT core (9) quickly and accurately feeds back the axial displacement of the push rod (15). Other sensors that can provide feedback signals for the closed-loop control of the main valve core position can also be used.

6. A high water base large flow digital proportional valve according to claim 1, characterized in that: The high-pressure side cone valve core (6), the low-pressure side cone valve core (7) and the push rod (15) are concentrically matched, and there is relative displacement between the high-pressure side cone valve core (6), the low-pressure side cone valve core (7) and the push rod (15). The inner matching surfaces of the high-pressure side cone valve core (6), the low-pressure side cone valve core (7) and the push rod (15) are provided with sliding sealing rings (13) to achieve sealing between the working chamber (A) and the high-pressure water inlet chamber (P) and the water return chamber (T).

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