CN117231798A - Bistable switch valve - Google Patents

Abstract

The invention belongs to the technical field of valves, and provides a bistable switch valve, wherein an upper pole piece and a lower pole piece are connected at the upper end and the lower end of a sleeve, a permanent magnet, an exciting coil and a valve shell are sequentially sleeved outside the sleeve in a coaxial manner, an armature cavity is arranged in the valve shell, the armature cavity is movably connected with an armature and a push rod, a main valve is sleeved at the lower end of the lower pole piece, a main valve core is arranged at the inner side of the main valve sleeve, a pilot cavity is formed among the main valve core, the valve shell and the lower pole piece, the lower pole piece is provided with a first through hole for communicating the armature cavity and the pilot cavity, the push rod stretches into the pilot cavity through the first through hole, the main valve is sleeved with an inlet runner and an outlet runner, a main valve cavity is circulated in the inlet runner and the outlet runner, the main valve core is provided with a second through hole which is communicated with the pilot cavity and the outlet runner in a radial direction. The invention has the advantages that: the switching of the switching state of the valve can be completed simply by changing the current direction, and the valve has the power-off self-locking capability at the steady-state position, so that the loss of electric energy is reduced, and the stability of the switching valve during operation is ensured.

Description

Bistable switch valve

Technical Field

The invention belongs to the technical field of valves, and particularly relates to a bistable switching valve.

Background

In fluid delivery systems such as automotive thermal management, hydraulic control, and lubrication and cooling, electromagnetic on-off valves are often used to control the on-off of a section of tubing. Electromagnetic switching valves are generally classified into a normally open valve type and a normally closed valve type, and the two types of electromagnetic valves do not need to be electrified in a default state and need to be continuously electrified in another state, so that the two types of electromagnetic valves mainly have the following two problems in actual use. Firstly, when the control circuit works in a non-default state, continuous power-on is needed, and the power consumption of the control circuit is increased; second, when the control circuit voltage is unstable, or power is accidentally lost, the solenoid valve may jump to a default state, possibly resulting in system instability.

Disclosure of Invention

The invention aims to provide a bistable switching valve, which can complete the switching of the switching state of the valve simply by changing the current direction after combining a permanent magnet and an exciting coil, has the power-off self-locking capability at a steady-state position, reduces the loss of electric energy and ensures the stability of the switching valve during operation.

The technical scheme adopted for solving the technical problems is as follows: a bistable switching valve is proposed, comprising: the upper pole piece and the lower pole piece are respectively connected with the upper end and the lower end of the sleeve, the permanent magnet, the exciting coil and the valve casing are sequentially sleeved on the outer side of the sleeve from inside to outside in a coaxial manner, an armature cavity is formed between the upper pole piece, the lower pole piece and the sleeve, the pilot control component comprises an armature and a push rod connected at the lower end of the armature, the armature is connected in the armature cavity in a sliding manner up and down, the upper part of the main valve sleeve is sleeved at the lower part of the lower pole piece, the main valve core is connected at the inner side of the main valve sleeve in an up-down movable manner, a pilot cavity is formed between the upper end of the main valve core, the main valve sleeve and the lower pole piece, a first through hole which is axially communicated is formed in the lower pole piece, the lower end of the push rod extends into the pilot cavity, at least one inlet flow passage is formed in the peripheral wall of the main valve sleeve, an axial outlet flow passage is formed in the lower end of the main valve sleeve, a main valve core is provided with a second through hole which is axially communicated with the lower end of the main valve sleeve, and a three-way seat which is axially communicated with the inlet flow passage and the second through hole, and the inlet seat which is axially communicated with the main valve seat when the main valve core is in the sealing seat and the lower end of the main valve seat which is in a sealing manner, and the main valve core, the main valve seat and the main valve sleeve form a main valve cavity, the main valve cavity is communicated with the inlet flow passage, the main valve core is provided with an orifice, the orifice is communicated with the pilot cavity and the main valve cavity, and the diameter of the orifice is smaller than that of the second through hole.

Compared with the prior art, the invention has the advantages that: when the exciting coil is used, the armature moves downwards under the action of the exciting coil and the permanent magnet, the armature drives the push rod to move downwards, the lower end of the push rod is abutted against the upper end of the second through hole of the main valve core, at the moment, the inlet runner is communicated with the pilot cavity through the orifice, the pressure at the inlet runner is consistent with the pressure of the pilot cavity, and the large pressure at the inlet runner is greater than that of the outlet runner, so that the main valve core and the armature synchronously move downwards under the pushing of the pressure until the lower end of the armature is abutted against the lower pole piece, and meanwhile, the lower end of the main valve core is abutted against the upper end of the main valve seat, and the main valve core blocks the circulation between the inlet runner and the outlet runner, so that the switching valve is in a closed state; then, the armature is powered off, the armature is kept to be abutted against the lower pole piece under the action of the permanent magnet, when the pressure at the inlet flow passage is increased, the balance between the pressure of the main valve cavity and the pressure of the pilot cavity is kept through the orifice, the excessive pressure at the inlet flow passage is avoided, the main valve core is pushed to move upwards, and the main valve cavity of the inlet flow passage and the main valve cavity of the outlet flow passage are communicated, so that the switching valve is invalid; the armature moves upwards under the action of the exciting coil and the permanent magnet, so that the upper end of the armature is abutted against the upper pole piece, at the moment, the second through hole is communicated with the outlet flow passage and the pilot cavity, so that the pressure at the position of the pilot cavity and the outlet flow passage is balanced, the pressure at the position of the inlet flow passage is increased, the diameter of the orifice is smaller than that of the second through hole, the flow resistance at the position of the orifice is far greater than that at the position of the second through hole, the pressure in the main valve cavity is far greater than that of the pilot cavity at the moment when the second through hole is opened, and the main valve cavity is pushed to move upwards under the action of the pressure of the main valve cavity, and the inlet flow passage and the outlet flow passage are communicated, so that the switch valve is in an opened state; and then the power supply is turned off, the armature is abutted against the lower end of the upper pole piece under the action of the permanent magnet, the main valve core is kept at a position far away from the main valve seat, and the switching valve is kept in an open state. When the exciting coil is electrified with positive current, the armature moves upwards under the action of the exciting coil and the permanent magnet, and when the exciting coil is electrified with negative current, the armature moves downwards under the action of the exciting coil and the permanent magnet, and the working principle is the same as that described above. Therefore, after the permanent magnet and the exciting coil are combined, the bistable switching valve can complete switching of the switching state of the valve simply by changing the current direction, has the power-off self-locking capability at the steady-state position, reduces the loss of electric energy and ensures the stability of the switching valve during working. The upper pole piece, the lower pole piece, the exciting coil and the permanent magnet are arranged to form a closed magnetic circuit, so that leakage of the magnetic circuit is avoided.

In the bistable switch valve, the magnetization direction of the permanent magnet is radial magnetization, so that the distribution direction of magnetic poles of the permanent magnet is axial after the magnetization is completed and the magnetic field is overlapped, and the acting force of magnetic force born by the armature is zero when the armature moves to the middle position of the permanent magnet under the action of no current; when the armature moves upwards continuously from the middle position, the magnetic force born by the armature is gradually increased and the direction is upwards; when the armature moves downwards continuously from the middle position, the magnetic force born by the armature is gradually increased and the direction is downwards.

In the bistable switch valve, a radial through hole is formed in the lower end of the push rod, the radial through hole is communicated with the pilot cavity, an axial through hole is further formed in the push rod, one end of the axial through hole is communicated with the armature cavity, and the other end of the axial through hole extends downwards to be communicated with the radial through hole. Through setting up radial through-hole and axial through-hole on the push rod, intercommunication armature chamber and guide chamber, avoid the pressure differential between armature chamber and the guide chamber to the influence of armature reciprocates, improve the accuracy of ooff valve control.

In the bistable switch valve, the pilot control assembly further comprises a spring and a first sealing gasket, a spring cavity is arranged on the inner side of the lower end of the push rod, the spring cavity is coaxially arranged and communicated with the axial through hole, the spring cavity extends to the lower end of the push rod, the spring is arranged in the spring cavity, the first sealing gasket is arranged below the spring, and the first sealing gasket is used for being matched with the second through hole. Through set up the spring in the push rod inboard, eliminate the influence of push rod and main valve core along axial upward processing dimensional error, guarantee that the first sealed pad of push rod lower extreme can be shutoff on the second through-hole of main valve core, the spring also plays buffering absorbing effect simultaneously to the spring chamber sets up with axial through-hole is coaxial, and processing is convenient. During assembly, the spring is inserted into the spring cavity from the lower end of the push rod, then the first sealing gasket is inserted into the spring cavity and is abutted against the ordering of the spring, and then the thin-wall structure at the lower end of the push rod is subjected to cold deformation under the action of the tool, so that the first sealing gasket is prevented from falling out of the spring cavity. When the switching valve is in a closed state, the push rod is abutted to the upper end of the second through hole of the main valve core through the first sealing gasket, the communication between the second through hole and the pilot cavity is blocked, and the inlet runner is prevented from being communicated with the outlet runner through the throttling hole, the pilot cavity and the second through hole, so that the switching valve is ensured to be in the closed state.

In the bistable switching valve, the sealing ring is arranged between the lower pole piece and the main valve sleeve, so that the tightness between the lower pole piece and the main valve sleeve is ensured, and the sealing performance of the switching valve is ensured.

In the bistable switching valve, a second sealing gasket is sleeved at the lower end of the main valve core, a fixed ring is connected at the lower end of the second sealing gasket, the inner side of the fixed ring is connected with the main valve core, and when the main valve core moves downwards to close a main valve cavity between an inlet of the switching valve and an outlet of the switching valve, the second sealing gasket is abutted with the upper end face of the main valve seat. During assembly, the main valve core is plugged into the inner cavity of the main valve sleeve, and then the main valve seat is plugged into the inner cavity of the main valve sleeve, so that the lower end of the main valve seat is in interference fit with the lower end of the main valve sleeve, and the main valve seat is positioned below the main valve core. When the switch valve is in a closed state, the second sealing gasket at the lower end of the main valve core is abutted to the upper end of the main valve seat, and the main valve core blocks the communication between the inlet flow passage and the outlet flow passage, so that the switch valve is closed. The second sealing gasket plays a sealing role, and the fixing ring is used for ensuring that the sealing gasket cannot fall off from the lower end of the main valve core.

In the bistable switch valve, the outer peripheral wall of the main valve core is provided with the annular groove, the annular groove is internally provided with the antifriction ring, the outer periphery of the antifriction ring is in sliding fit with the inner wall of the main valve sleeve, the antifriction ring can reduce abrasion when the main valve core moves up and down relative to the main valve sleeve, and meanwhile, the bistable switch valve also has a sealing effect, namely, the antifriction ring has a sealing effect in the up and down sliding process of the main valve core relative to the main valve sleeve, so that the leakage amount between the main valve core and the main valve sleeve is reduced, and the influence on the use of the switch valve is avoided.

In the bistable switch valve, the pilot control assembly further comprises an upper buffer pad and a lower buffer pad, buffer grooves are coaxially formed in the upper end and the lower end of the armature, the upper buffer pad and the lower buffer pad are respectively arranged in the buffer grooves, and the end faces of the upper buffer pad and the lower buffer pad are exposed out of the buffer grooves. The upper cushion pad and the lower cushion pad are pressed into the buffer groove through interference fit, and the buffer and shock absorption effects are achieved in the up-and-down movement process of the armature.

In the bistable switch valve, an upper magnetic ring and a lower magnetic ring are respectively arranged on the upper side and the lower side of the permanent magnet, an upper magnetism isolating ring is arranged between the upper magnetic ring and the permanent magnet, a lower magnetism isolating ring is arranged between the lower magnetic ring and the permanent magnet, and the upper magnetic ring, the lower magnetic ring, the upper magnetism isolating ring and the lower magnetism isolating ring are all sleeved on the outer side of the permanent magnet. The upper magnetic ring and the lower magnetic ring play a role in magnetic conduction, namely, the originally lost magnetic flux plays a role, so that the main magnetic flux is improved.

In the bistable switch valve, the valve shell and the upper pole piece are connected through bolts, and the valve shell and the upper pole piece can also be fixedly connected in a threaded connection, welding and other manners, which are all within the protection scope of the invention

Drawings

FIG. 1 is a schematic view of the overall structure of an embodiment of the present invention;

FIG. 2 is a cross-sectional view of one embodiment of the present invention;

FIG. 3 is a second cross-sectional view of one embodiment of the present invention;

FIG. 4 is a cross-sectional view of a pilot control assembly according to one embodiment of the invention;

fig. 5 is a schematic structural view of a main valve element according to an embodiment of the present invention.

In the figure, 1, a valve housing; 2. a main valve sleeve; 3. a pole piece is arranged on the upper part; 4. a lower pole piece; 5. a sleeve; 6. an exciting coil; 7. a permanent magnet; 8. a pilot control assembly; 9. a main spool; 10. an armature cavity; 11. an armature; 12. a push rod; 13. a pilot cavity; 14. a first through hole; 15. an inlet flow passage; 16. an outlet flow passage; 17. a main valve cavity; 18. a second through hole; 19. a radial through hole; 20. an axial through hole; 21. a spring; 22. a first gasket; 23. a spring cavity; 24. a seal ring; 25. a main valve seat; 26. a third through hole; 27. a second gasket; 28. a fixing ring; 29. an antifriction ring; 30. an upper cushion pad; 31. a lower cushion pad; 32. a buffer tank; 33. a magnetic conduction ring is arranged on the upper part; 34. a lower magnetic conduction ring; 35. a magnetism isolating ring is arranged on the upper part; 36. a lower magnetism isolating ring; 37. a bolt; 38. a copper coil; 39. a spool; 40. an orifice.

Detailed Description

The following are specific embodiments of the present invention and the technical solutions of the present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1 to 5, a bistable switching valve of the present invention includes: valve casing 1, main valve cover 2, upper pole piece 3, lower pole piece 4, sleeve 5, exciting coil 6, permanent magnet 7, pilot control assembly 8, main valve core 9. The upper pole piece 3 and the lower pole piece 4 are made of ferromagnetic materials, the sleeve 5 is made of nonferromagnetic materials, the upper pole piece 3 and the lower pole piece 4 are respectively connected to the upper end and the lower end of the sleeve 5 and are fixed through welding, the upper pole piece 3, the lower pole piece 4 and the sleeve 5 form a semi-sealed cavity, which is called an armature cavity 10, the armature cavity 10 is communicated with the outside through a first through hole 14 on the lower pole piece 4, and the first through hole 14 penetrates through the lower pole piece 4 along the axial direction. The permanent magnet 7 is of a whole circular ring structure, and can also be of a plurality of circular arc structures spliced together to form the whole circular ring structure, the permanent magnet 7 is more convenient to install, and the permanent magnet 7 is fixedly connected to the outer surface of the sleeve 5 through glue or axial interference. The exciting coil 6 comprises a copper coil 38 and a winding shaft 39, the copper coil 38 is wound on the winding shaft 39 to form the exciting coil 6, the exciting coil 6 is sleeved on the periphery of the permanent magnet 7, the valve housing 1 is made of ferromagnetic materials and sleeved on the periphery of the exciting armature 11, and the valve housing 1 is fixed on the upper pole piece 3 through a bolt 37 and is in interference connection with the outer cylindrical surface of the lower pole piece 4. The upper pole piece 3, the lower pole piece 4, the exciting coil 6 and the permanent magnet 7 form a closed magnetic circuit, and leakage of the magnetic circuit is avoided. In the invention, the valve casing 1 can be canceled by changing the design parameters of the exciting coil 6 and the permanent magnet 7 to achieve the same effect as that of the valve casing 1, and in addition, the valve casing 1, the upper pole piece 3 and the lower pole piece 4 can also adopt the connection modes of screw threads, welding and the like, which are also within the protection scope of the invention.

The upper portion of main valve housing 2 cup joints the lower part of the outer cylinder of lower pole piece 4, be equipped with sealing washer 24 between lower pole piece 4 and main valve housing 2, sealing washer 24 suit is in the seal groove of lower pole piece 4, guarantee the sealing performance of ooff valve, main valve housing 2 and lower pole piece 4 pass through welded fastening, afterwards, main valve core 9 is packed into main valve housing 2 along the axial, be equipped with antifriction ring 29 between main valve housing 2 and main valve core 9, reduce the wearing and tearing when main valve core 9 reciprocates relative main valve housing 2, be equipped with the mounting groove at the lower extreme of main valve housing 2, the interference fit is connected with second sealing washer 27 in the mounting groove, second sealing washer 27 can adopt metal or plastics material to make, the lower extreme of second sealing washer 27 is equipped with the mounting groove, the interference connection has solid fixed ring 28 in the mounting groove, gu fixed ring 28 is used for guaranteeing that second sealing washer 27 can not drop from main valve core 9's tip, then with main valve seat 25 along the axial pressure main valve housing 2, and make the lower extreme of main valve seat 25 and main valve housing 2 cooperate and sealing connection, so as to prevent main valve core 9 from deviating from inside of interference housing 2. After the main valve core 9 is plugged into the inner cavity of the main valve sleeve 2, a cavity between the upper end of the main valve core 9, the main valve sleeve 2 and the lower pole piece 4 is called as a pilot cavity 13, at least one inlet runner 15 is uniformly distributed on the side wall of the main valve sleeve 2 along the axial interval, an axial outlet runner 16 is arranged at the lower end of the main valve sleeve 2, a through second through hole 18 is radially arranged on the main valve core 9, the second through hole 18 is communicated with the pilot cavity 13 and the outlet runner 16, a first through hole 14 of the lower pole piece 4 is communicated with the armature cavity 10 and the pilot cavity 13, and the first through hole 14 and the second through hole 18 are both arranged on the same radial line and are positioned at the center position. The main valve seat 25 is provided with a third through hole 26 along the radial direction, the third through hole 26 is communicated with the second through hole 18 and the outlet flow passage 16, when the main valve core 9 moves downwards to be abutted with the main valve seat 25, the main valve core 9 blocks the communication between the inlet flow passage 15 and the outlet flow passage 16, a main valve cavity 17 is formed among the main valve core 9, the main valve seat 25 and the main valve sleeve 2, and the main valve cavity 17 is communicated with the inlet flow passage 15. An orifice 40 is further provided in the main spool 9, the orifice 40 communicates the main valve chamber 17 and the pilot chamber 13, and the diameter of the orifice 40 is smaller than the diameter of the second through hole 18.

The pilot control assembly 8 includes an armature 11, an upper cushion 30, a lower cushion 31, a pushrod 12, a spring 21, and a first seal 22. The armature 11 adopts ferromagnetic material, and armature 11 swing joint is in armature chamber 10, and armature 11 can reciprocate along armature chamber 10, and push rod 12 is connected to the lower extreme of armature 11, and push rod 12 and armature 11 interference fit are connected, and push rod 12 adopts non-ferromagnetic material, and the lower extreme of push rod 12 stretches into in the guide chamber 13 through first through-hole 14. According to the invention, the magnetizing direction of the permanent magnet 7 is radial magnetizing, so that after the magnetizing is completed and the magnetic field is overlapped, the magnetic pole distribution direction of the permanent magnet 7 is axial, and the acting force of the magnetic force born by the armature 11 is zero when the armature 11 moves to the middle position of the permanent magnet 7 under the action of no current; when the armature 11 continuously moves upwards from the intermediate position, the magnetic force born by the armature 11 gradually increases and the direction is upwards; as the armature 11 continues to move downward from the neutral position, the magnetic force experienced by the armature 11 increases gradually, in a downward direction. The upper end and the lower end of the armature 11 are coaxially provided with buffer grooves 32, the upper buffer pad 30 and the lower buffer pad 31 are made of plastic materials, and the upper buffer pad 30 and the lower buffer pad 31 are pressed into annular grooves on the armature 11 in an interference manner, so that the effects of buffering and damping are achieved. The lower extreme of push rod 12 is equipped with radial through-hole 19, and radial through-hole 19 and pilot chamber 13 communicate, is equipped with axial through-hole 20 on the push rod 12, and axial through-hole 20 one end and armature chamber 10 communicate, and the other end downwardly extending communicates with radial through-hole 19, through radial through-hole 19 and axial through-hole 20, communicates armature chamber 10 and pilot chamber 13, avoids the influence of the pressure differential between armature chamber 10 and pilot chamber 13 to armature 11 reciprocates, improves the accuracy of ooff valve control. The inner side of the lower end of the push rod 12 is provided with a spring cavity 23, the spring cavity 21 is coaxially arranged and communicated with the axial through hole 20, the spring cavity 23 extends to the lower end of the push rod 12, a spring 21 is arranged in the spring cavity 23, a first sealing gasket 22 is arranged below the spring 21, the first sealing gasket 22 is made of metal or plastic materials, the spring 21 and the first sealing gasket 22 are sequentially arranged in the spring cavity 23 of the push rod 12, the thin-wall structure at the end part of the push rod 12 is subjected to cold deformation under the action of a fixture, so that the first sealing gasket 22 is prevented from being separated from the spring cavity 23, the spring 21 eliminates the influence of machining dimensional errors of the push rod 12 and the main valve core 9 in the axial direction, the first sealing gasket 22 at the lower end of the push rod 12 can be blocked on the second through hole 18 of the main valve core 9, and meanwhile, the spring 21 also plays a role in buffering and damping. When the switching valve is in a closed state, the push rod 12 is abutted to the upper end of the second through hole 18 of the main valve core 9 through the first sealing gasket 22, so that the communication between the second through hole 18 and the pilot cavity 13 is blocked, and the inlet flow passage 15 is prevented from being communicated with the outlet flow passage 16 through the main valve cavity 17, the throttle hole 40, the pilot cavity 13 and the second through hole 18, so that the switching valve is ensured to be in the closed state.

As a preferred technical scheme, in the invention, an upper magnetic conducting ring 33 and a lower magnetic conducting ring 34 can be respectively arranged on the upper side and the lower side of the permanent magnet 7, an upper magnetism isolating ring 35 is arranged between the upper magnetic conducting ring 33 and the permanent magnet 7, a lower magnetism isolating ring 36 is arranged between the lower magnetic conducting ring 34 and the permanent magnet 7, the upper magnetic conducting ring 33, the lower magnetic conducting ring 34, the upper magnetism isolating ring 35 and the lower magnetism isolating ring 36 are all sleeved on the outer side of the permanent magnet 7, the upper magnetic conducting ring 33 and the lower magnetic conducting ring 34 are all made of ferromagnetic materials, the upper magnetism isolating ring 35 and the lower magnetism isolating ring 36 are all made of plastic materials, and the upper magnetic conducting ring 33 and the lower magnetic conducting ring 34 play a role in magnetic conduction, namely, the originally lost magnetic flux is enabled to act, and the main magnetic flux is improved. In the invention, the upper and lower magnetic conductive rings can be canceled by changing the design parameters of the exciting coil 6 and the permanent magnet 7, so as to achieve the same effect as the effect of reserving the magnetic conductive rings. The upper and lower magnetic conductive rings can be combined with the upper pole piece 3 and the lower pole piece 4 to form a part.

Working principle: when the exciting coil 6 is used, assuming that the armature 11 moves downwards under the action of the exciting coil 6 and the permanent magnet 7 when forward current is fed, the armature 11 drives the push rod 12 to move downwards, the lower end of the push rod 12 is abutted against the upper end of the second through hole 18 of the main valve core 9, at the moment, the inlet runner 15 is communicated with the pilot cavity 13 through the orifice 40, the pressure at the inlet runner 15 is consistent with the pressure of the pilot cavity 13, the large pressure at the inlet runner 15 is greater than the outlet runner 16, so that the main valve core 9 and the armature 11 synchronously move downwards under the pushing of the pressure until the lower end of the armature 11 is abutted against the lower pole piece 4, and meanwhile, the lower end of the main valve core 9 is abutted against the upper end of the main valve seat 25, and the main valve core 9 blocks the communication between the inlet runner 15 and the outlet runner 16, so that the switch valve is in a closed state; after the power is off, the armature 11 is kept to be abutted against the lower pole piece 4 under the action of the permanent magnet 7, when the pressure at the inlet runner 15 is increased, the balance of the pressure of the main valve cavity 17 and the pressure of the pilot cavity 13 is kept through the orifice 40, the excessive pressure at the inlet runner 15 is avoided, the main valve core 9 is pushed to move upwards, and the main valve cavity 17 of the inlet runner 15 and the outlet runner 16 is communicated, so that the switching valve is invalid; the armature 11 moves upwards under the action of the exciting coil 6 and the permanent magnet 7, so that the upper end of the armature 11 is abutted against the upper pole piece 3, at the moment, the second through hole 18 is communicated with the outlet flow passage 16 and the pilot cavity 13, so that the pressure at the position of the pilot cavity 13 and the outlet flow passage 16 is balanced, the pressure at the position of the inlet flow passage 15 is increased, the diameter of the throttle hole 40 is smaller than that of the second through hole 18, the flow resistance at the position of the throttle hole 40 is far greater than that at the position of the second through hole 18, the pressure in the main valve cavity 17 is far greater than that of the pilot cavity 13 at the moment when the second through hole 18 is opened, and the main valve core 9 is pushed to move upwards under the action of the pressure of the main valve cavity 17, the inlet flow passage 15 and the outlet flow passage 16 are communicated, and the switch valve is in an open state; then the power supply is turned off, the armature 11 is abutted against the lower end of the upper pole piece 3 under the action of the permanent magnet 7, the main valve core 9 is kept at a position far away from the main valve seat 25, and the switching valve is kept in an open state. When the exciting coil 6 is electrified with positive current, the armature 11 moves upwards under the action of the exciting coil 6 and the permanent magnet 7, and when the exciting coil 6 is electrified with negative current, the armature 11 moves downwards under the action of the exciting coil 6 and the permanent magnet 7, and the working principle is the same as that described above.

Therefore, after the permanent magnet 7 and the exciting coil 6 are combined, the bistable switching valve can complete the switching of the switching state of the valve simply by changing the current direction, has the power-off self-locking capability at the steady-state position, reduces the loss of electric energy and ensures the stability of the switching valve during working.

The specific embodiments described herein are offered by way of example only. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions thereof without departing from the scope of the invention as defined.

Claims (10)

1. A bistable switching valve, comprising: valve casing (1), main valve cover (2), go up pole piece (3), lower pole piece (4), sleeve pipe (5), exciting coil (6), permanent magnet (7), pilot control subassembly (8), main valve core (9), go up pole piece (3) and lower pole piece (4) and connect respectively the upper and lower both ends of sleeve pipe (5), the outside of sleeve pipe (5) is from inside to outside with the axle sleeve in proper order establish permanent magnet (7), exciting coil (6) and valve casing (1), go up pole piece (3), lower pole piece (4) with form armature chamber (10) between sleeve pipe (5), pilot control subassembly (8) include armature (11) and push rod (12) of connection in armature (11) lower extreme, armature (11) from top to bottom sliding connection is in armature chamber (10), the upper portion of main valve cover (2) cup joints the lower part of lower pole piece (4), main valve core (9) are gone up from top to bottom swing joint and are in main valve cover (2) inboard, main valve core (9) upper end, cover (2) and lower pole piece (4) are equipped with one and link up between pole piece (14) and form one axial through hole (13), the lower extreme of push rod (12) stretches into through first through-hole (14) pilot chamber (13), be equipped with at least one import runner (15) on the perisporium of main valve cover (2), the lower extreme of main valve cover (2) is equipped with axial export runner (16), main valve core (9) are equipped with along the second through-hole (18) that link up axially, second through-hole (18) intercommunication pilot chamber (13) and export runner (16), exciting coil (6) with permanent magnet (7) are used for driving push rod (12) reciprocate, when push rod (12) down move with main valve core (9) butt, push rod (12) shutoff is in the upper end of second through-hole (18), the below of main valve core (9) is equipped with main valve seat (25), the lower extreme of main valve seat (25) with the inner wall joint of the lower extreme of main valve cover (2), main valve seat (25) are equipped with third through-hole (26) along the axial, third through-hole (26) are equipped with main valve seat (25), third through-hole (26) and export (16) when the shutoff of main valve core (9) move down, the through-hole (16) and the passageway (9) are connected respectively A main valve cavity (17) is formed between a main valve seat (25) and a main valve sleeve (2), the main valve cavity (17) is communicated with an inlet flow passage (15), an orifice (40) is arranged on a main valve core (9), the orifice (40) is communicated with a pilot cavity (13) and the main valve cavity (17), and the diameter of the orifice (40) is smaller than that of a second through hole (18).

2. A bistable switching valve according to claim 1, characterized in that the direction of magnetization of said permanent magnet (7) is radial magnetization.

3. Bistable switching valve according to claim 1, characterized in that the lower part of the push rod (12) is provided with a radial through hole (19), the radial through hole (19) is communicated with the pilot cavity (13), the push rod (12) is further provided with an axial through hole (20), one end of the axial through hole (20) is communicated with the armature cavity (10), and the other end of the axial through hole (20) extends downwards to be communicated with the radial through hole (19).

4. A bistable switch valve according to claim 3, characterized in that said pilot control assembly (8) further comprises a spring (21) and a first gasket (22), a spring chamber (23) is provided inside the lower end of said push rod (12), said spring chamber (23) is coaxially arranged and communicates with said axial through hole (20), said spring chamber (23) extends to the lower end of said push rod (12), said spring (21) is provided in said spring chamber (23), said first gasket (22) is provided at the lower end of said spring (21), said first gasket (22) is adapted to cooperate with said second through hole (18).

5. Bistable switching valve according to claim 1, characterized in that a sealing ring (24) is arranged between the lower pole piece (4) and the main valve sleeve (2).

6. A bistable switch valve according to claim 1, characterized in that the lower end of the main valve core (9) is sleeved with a second sealing gasket (27), the lower end of the second sealing gasket (27) is connected with a fixing ring (28), the inner side of the fixing ring (28) is connected with the main valve core (9), and when the main valve core (9) moves downwards to be abutted with the main valve seat (25), the second sealing gasket (27) is abutted with the upper end face of the main valve seat (25).

7. Bistable switching valve according to claim 1, characterized in that the peripheral wall of the main valve core (9) is provided with an annular groove, an antifriction ring (29) is arranged in the annular groove, and the periphery of the antifriction ring (29) is in sliding fit with the inner wall of the main valve sleeve (2).

8. The bistable switch valve according to claim 1, characterized in that said pilot control assembly (8) further comprises an upper buffer pad (30) and a lower buffer pad (31), said armatures (11) are coaxially provided with buffer grooves (32) at both upper and lower ends, said buffer grooves (32) are respectively provided with said upper buffer pad (30) and said lower buffer pad (31), and the end surfaces of said upper buffer pad (30) and said lower buffer pad (31) are exposed outside said buffer grooves (32).

9. The bistable switch valve according to claim 1, wherein an upper magnetic conducting ring (33) and a lower magnetic conducting ring (34) are respectively arranged on the upper side and the lower side of the permanent magnet (7), an upper magnetism isolating ring (35) is arranged between the upper magnetic conducting ring (33) and the permanent magnet (7), a lower magnetism isolating ring (36) is arranged between the lower magnetic conducting ring (34) and the permanent magnet (7), and the upper magnetic conducting ring (33), the lower magnetic conducting ring (34), the upper magnetism isolating ring (35) and the lower magnetism isolating ring (36) are all sleeved on the outer side of the permanent magnet (7).

10. A bistable switching valve according to claim 1, characterized in that said valve housing (1) is connected to said upper pole piece (3) by means of bolts (37).