CN114321063B

CN114321063B - Piston valve and vehicle

Info

Publication number: CN114321063B
Application number: CN202111604493.6A
Authority: CN
Inventors: 何浴辉; 宛勇健; 倪辉
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2024-09-17
Anticipated expiration: 2041-12-24
Also published as: CN114321063A

Abstract

The embodiment of the application provides a piston valve and a vehicle. The piston valve comprises a cylinder body, the annular side wall is provided with a fluid inlet and a fluid outlet; a piston movable in an axial direction within the cylinder; the reversing mechanism is arranged at the gap between the cylinder body and the piston around the circumferential direction of the piston, is positioned between the fluid inlet and the fluid outlet along the axial direction and is communicated with the fluid outlet, and when the piston moves along the axial direction, the reversing mechanism is switched between a one-way conduction state and a two-way conduction state, and can seal the gap in one direction, prevent fluid from flowing from the fluid inlet to the fluid outlet and enable the fluid to flow back from the fluid outlet to the fluid inlet; in a bi-directional conducting state, the reversing mechanism enables bi-directional fluid flow between the fluid inlet and the fluid outlet. The embodiment of the application realizes the function of integrating the check valve on the piston valve, ensures that the high-pressure fluid at the fluid outlet can flow back to the fluid inlet when the pressure of the fluid inlet is reduced, has less parts, reduces the leakage risk, improves the reliability and reduces the cost.

Description

Piston valve and vehicle

Technical Field

The application relates to the field of vehicles, in particular to a piston valve and a vehicle.

Background

An electro-mechanical brake system (electro-MECHANICAL BRAKE, EMB) is a brake system in a vehicle, which uses the electro-mechanical system to replace a hydraulic device, has extremely high response speed, greatly shortens the braking distance, and is simple to arrange and lighter due to the absence of the hydraulic system, so that the functions of electronic parking, anti-lock, braking force distribution and the like are convenient to integrate. However, EMB has no mechanical failure protection device, and the system safety and reliability are insufficient.

In order to solve the safety and reliability problems of EMB, a hybrid braking system based on hydraulic and electronic machinery is formed. In the hybrid braking system, a piston valve, such as a two-position three-way solenoid valve, may be used to switch between a hydraulic braking mode and an electromechanical braking mode. When braking is carried out in a hydraulic braking mode, brake fluid in the hydraulic assembly flows into a brake cylinder to provide braking force; when braking is carried out in an electromechanical braking mode, the electronic equipment acquires a braking signal to control wheels to provide braking force, and brake fluid in the hydraulic assembly flows into the pedal feel simulator to provide feedback force so as to avoid stepping on the air.

In addition, in order to prevent that the brake fluid pressure in the brake cylinder and the pedal feel simulator is greater than the brake fluid pressure in the hydraulic component, a first one-way valve is independently arranged between the brake cylinder and the hydraulic component, and a second one-way valve is independently arranged between the pedal feel simulator and the hydraulic component, so that the one-way valve can assist a system in quick pressure release, and on the other hand, when the pressure in the hydraulic component is reduced, high-pressure fluid in the brake cylinder and the pedal feel simulator can smoothly flow back to the hydraulic component, and the probability of danger is reduced.

Because the check valve and the piston valve are independently arranged, the number of parts of the system and the flow channels are more, the leakage risk is increased, the cost is not beneficial to being reduced, and meanwhile, the occupied volume of the system is larger, and the miniaturization is not beneficial to being realized.

Disclosure of Invention

The embodiment of the application provides a piston valve and a vehicle, which realize the function of integrating a one-way valve on the piston valve, ensure that high-pressure fluid at a fluid outlet can flow back to the fluid inlet when the pressure at the fluid inlet is reduced, ensure that the pressure at the fluid outlet in a stable state is not greater than the pressure at the fluid inlet, reduce the number of parts and the number of channels, reduce the leakage risk, improve the reliability, reduce the cost and facilitate the realization of miniaturization.

For this purpose, the embodiment of the application adopts the following technical scheme:

In a first aspect, an embodiment of the present application provides a piston valve, including: a cylinder body, the annular side wall of which is provided with a fluid inlet and at least one fluid outlet at intervals along the axial direction; a piston movable in the axial direction within the cylinder; at least one reversing mechanism disposed at a gap of the cylinder and the piston around a circumferential direction of the piston, the reversing mechanism being located between the fluid inlet and the fluid outlet in the axial direction and being in communication with the fluid outlet, the reversing mechanism being switchable between a unidirectional conducting state and a bidirectional conducting state when the piston is moved in the axial direction, wherein: in the unidirectional conductive state, the reversing mechanism is capable of unidirectional sealing the gap to prevent fluid flow from the fluid inlet through the reversing mechanism to the fluid outlet and to enable backflow of the fluid from the fluid outlet through the reversing mechanism to the fluid inlet; in the bi-directional conduction state, the reversing mechanism is capable of flowing the fluid from the fluid inlet to the fluid outlet through the reversing mechanism or capable of reversing the fluid from the fluid outlet to the fluid inlet through the reversing mechanism.

According to the piston valve provided by the embodiment of the application, the unidirectional conduction or the bidirectional conduction between the fluid inlet and the fluid outlet can be realized through the reversing mechanism, the function of integrating the unidirectional valve on the piston valve is realized, and when the pressure at the fluid inlet is reduced, the high-pressure fluid at the fluid outlet can flow back to the fluid inlet, so that the pressure at the fluid outlet in a stable state is not greater than the pressure at the fluid inlet, the probability of danger is reduced, the number of parts and the number of flow channels are reduced, the leakage risk is reduced, the reliability is improved, the cost is reduced, and the miniaturization is facilitated.

In one possible implementation, the reversing mechanism includes: a ring groove provided on one of an inner wall of the cylinder and an outer wall of the piston, and a one-way seal provided inside the ring groove; an annular outer wall and an annular groove channel, adjacently disposed on the other of the inner wall of the cylinder body and the outer wall of the piston, and the fluid inlet and the annular groove channel are located on both sides of the annular outer wall in the axial direction, the fluid outlet is communicated with the annular groove channel, wherein: in the one-way conduction state, the one-way seal is in contact with the annular outer wall, the one-way seal being capable of sealing the gap in a direction from the fluid inlet to the annular channel and of flowing fluid through the gap in a direction from the annular channel to the fluid inlet to return to the fluid inlet; in the bi-directional conductive state, the one-way seal corresponds to the annular channel, enabling the fluid to flow through the annular channel in a direction from the fluid inlet to the annular channel to flow to the fluid outlet or in a direction from the annular channel to the fluid inlet to flow back to the fluid inlet.

That is, in this implementation, the annular outer wall and the annular groove channel may be disposed adjacently on the inner wall of the cylinder, the annular groove may be disposed on the outer wall of the piston, and the one-way seal may be disposed in the annular groove. Or the outer wall of the piston can be adjacently provided with an annular outer wall and an annular groove channel, the inner wall of the cylinder body can be provided with an annular groove, and the unidirectional sealing element can be arranged in the annular groove. The one-way seal is realized when the one-way seal is in contact with the annular outer wall, fluid at the fluid inlet is prevented from flowing to the fluid outlet through the one-way seal, and the fluid at the fluid outlet can pass through a gap between the one-way seal and the annular outer wall so as to flow back to the fluid inlet; when the one-way seal is in contact with the annular channel, fluid is able to flow bi-directionally through the annular channel at the one-way seal.

In one possible implementation, the unidirectional seal comprises a lip seal having a lip facing the side of the fluid inlet, wherein: under the condition that the unidirectional sealing piece is correspondingly contacted with the annular outer wall, when the pressure of fluid at the lip side is greater than that of fluid at the opposite side of the lip, the lip of the lip sealing ring is enabled to be tightly attached to the annular outer wall, and the gap is sealed along the direction from the fluid inlet to the annular groove channel; when the fluid pressure of the lip side is smaller than that of the opposite side of the lip, the lip contracts to enable the lip of the lip-shaped sealing ring to be separated from the annular outer wall to form a gap, so that the fluid can flow from the opposite side of the lip to the lip side through the gap, and one-way sealing or one-way conduction can be realized; in the case where the one-way seal corresponds to the annular groove passage, when the pressure of the fluid on the lip side is greater than the pressure of the fluid on the opposite side of the lip, the fluid can flow from the lip side to the opposite side of the lip through the annular groove passage; when the pressure of the fluid on the lip side is smaller than the pressure of the fluid on the opposite side of the lip, the fluid can flow from the opposite side of the lip to the lip side through the annular groove passage, thereby realizing bidirectional communication.

That is, in this implementation, the one-way seal may be a lip seal. The lip of the lip-shaped sealing ring deforms under the action of hydraulic pressure, so that the lip is tightly attached to the sealing surface. The higher the hydraulic pressure, the tighter the lip and the sealing surface are stuck, and the sealing lip has certain automatic compensation capability after being worn. Because the O-shaped sealing ring needs interference fit to seal when sealing, namely needs precompression, the motion resistance is larger, more power is consumed, the volume of the driving mechanism is larger, in addition, the size of the O-shaped sealing ring along the axial direction is larger than that of the lip-shaped sealing ring, after the O-shaped sealing ring is precompressed, the size along the axial direction is further increased, the motion stroke of the piston when the piston is switched between a sealing state and a conducting state is larger, and the structural volume is larger. The lip sealing ring has no precompression, small movement resistance, and reduces the sliding resistance of the piston valve, and meanwhile, the lip sealing ring relies on lip sealing, so that the axial size is small, the movement stroke of the piston valve is reduced, and the power consumption of a driving mechanism for driving the piston to move is reduced.

In one possible implementation, the annular groove channel includes a plurality of groove bodies spaced apart in a circumferential direction around the other of the inner wall of the cylinder body and the outer wall of the piston, the outer wall between adjacent groove bodies being capable of supportingly contacting the unidirectional seal when the unidirectional seal corresponds to the annular groove channel.

That is, in this implementation, the annular groove channel is an intermittent groove design along the circumferential direction, so that a large lip of the lip seal can be reliably supported, so that the lip seal can realize on-off of liquid without significant deformation, overturn can be effectively prevented, and the life of the lip seal is also improved.

In one possible implementation, the dimension of the groove body in the axial direction is greater than or less than or equal to the dimension in the circumferential direction; and/or the longitudinal section or the cross section of the groove body is arc-shaped, and two ends of the arc along the bending direction are far away from the central axis of the piston relative to the middle part of the arc.

That is, in this implementation, the dimension of the slot body along the axial direction may be greater than the dimension along the circumferential direction, for example, the slot body is an elongated slot, the length of which along the axial direction coincides with the flow direction of the fluid, so that more slot bodies may be disposed along the circumferential direction, so that the fluid may flow through the multiple slot bodies separately in multiple ways, so that the stress is more uniform; or the dimension of the groove body along the axial direction can be smaller than the dimension along the circumferential direction, so that the groove body is wider, can contain more fluid, and can enable the fluid to pass through the groove body faster. Of course, the dimension of the groove body in the axial direction may be equal to the dimension in the circumferential direction. In addition, the cross section of cell body can be selected according to the work needs, for example, the cross section of cell body is the arc, and the flow channel that the cell body formed is comparatively smooth like this, makes things convenient for fluid to get into the cell body and follow the cell body and flows out, and the fluid can pass through more smoothly promptly, is difficult for making the fluid remain, is favorable to accelerating fluid velocity. Of course, other shapes of the trough body may be selected, such as a rectangular cross section.

In one possible implementation manner, the cylinder body is provided with two fluid outlets, the fluid inlet is located between the two fluid outlets along the axial direction, the two fluid outlets are a first fluid outlet and a second fluid outlet, and the piston valve comprises two reversing mechanisms, and the two reversing mechanisms are a first reversing mechanism and a second reversing mechanism; the first reversing mechanism is located between the fluid inlet and the first fluid outlet along the axial direction and is communicated with the first fluid outlet, and the second reversing mechanism is located between the fluid inlet and the second fluid outlet along the axial direction and is communicated with the second fluid outlet; the piston is movable between a first position and a second position, wherein: when the first reversing mechanism is in the bidirectional conduction state, the second reversing mechanism is in the unidirectional conduction state; and when the first reversing mechanism is in the second position, the first reversing mechanism is in the unidirectional conduction state, and the second reversing mechanism is in the bidirectional conduction state.

That is, in this implementation, the piston valve may include one fluid inlet and two fluid outlets, the piston valve may be a two-position three-way solenoid valve, and two reversing mechanisms are disposed on the piston valve, and the two reversing mechanisms have different conducting states, specifically, when the piston is at the first position, the first reversing mechanism may be in a two-way conducting state, and the second reversing mechanism may be in a one-way conducting state; when the piston moves to the second position, the first reversing mechanism can be in a one-way conduction state, and the second reversing mechanism can be in a two-way conduction state. The first reversing mechanism can realize unidirectional conduction or bidirectional conduction between the fluid inlet and the first fluid outlet, ensures that high-pressure fluid at the first fluid outlet can flow back to the fluid inlet when the pressure at the fluid inlet is reduced, ensures that the pressure at the first fluid outlet in a stable state is not greater than the pressure at the fluid inlet, and the second reversing mechanism can realize unidirectional conduction or bidirectional conduction between the fluid inlet and the second fluid outlet, ensures that the high-pressure fluid at the second fluid outlet can flow back to the fluid inlet when the pressure at the fluid inlet is reduced, ensures that the pressure at the second fluid outlet in a stable state is not greater than the pressure at the fluid inlet, reduces the probability of danger, simultaneously does not need to independently arrange a one-way valve, reduces the number of parts and channels, reduces the leakage risk, improves the reliability, reduces the cost and is beneficial to realizing miniaturization.

In one possible implementation, an annular channel is provided on the other of the inner wall of the cylinder and the outer wall of the piston, the fluid inlet communicates with the annular channel, and the annular channel is the same as or different from the annular channel structure of the reversing mechanism.

That is, in this implementation, in order to enable the liquid at the fluid inlet to flow into the gap between the cylinder and the piston as soon as possible, the size of the gap at the fluid inlet may be increased, and in particular, an annular passage may be provided on the outer wall of the piston, or an annular passage may be provided on the inner wall of the cylinder. The annular channel may be located between the annular outer wall of the first reversing mechanism and the annular outer wall of the second reversing mechanism.

In one possible implementation, the piston valve further includes: a first seal ring located at a first end of the piston and capable of sealing a circumferential gap between the cylinder and the piston in a direction from a second end of the piston to the first end of the piston; a second seal ring located at the second end of the piston and capable of sealing a circumferential gap between the cylinder and the piston in a direction from the first end of the piston to the second end of the piston; the fluid inlet, the fluid outlet, and the reversing mechanism are located between the first seal ring and the second seal ring along the axial direction.

That is, in this implementation, in order to ensure that fluid does not flow out from both ends of the piston along the gap between the piston and the cylinder, sealing may be performed by providing sealing rings at both ends of the piston, which are required to seal the gap at least in the direction toward the outside at both ends of the piston. Here, "outward direction" refers to a direction away from the fluid inlet in an axial direction at the end of the piston. Specifically, at a first end of the piston, "outward direction" refers to the direction of the second end of the fluid inlet/piston to the first end of the piston; at the second end of the piston, "outward direction" refers to the direction of the first end of the fluid inlet/piston to the second end of the piston.

In one possible implementation, the first seal ring and the second seal ring are each one of an O-ring seal and a lip seal ring, wherein: the O-ring is capable of bi-directionally sealing the gap in a direction from the first end of the piston to the second end of the piston and in a direction from the second end of the piston to the first end of the piston; the lip seal is open toward the side of the fluid inlet, and is capable of unidirectionally sealing the gap in a direction from the lip side to the opposite side of the lip.

That is, in this implementation, the seal ring may bi-directionally seal the gap along the axial direction at both ends of the piston, where "bi-directionally seal" refers to a direction along the first end to the second end of the piston and a direction along the second end to the first end of the piston, where an O-ring seal may be employed to achieve bi-directional sealing; or the seal rings unidirectionally seal the gap at both ends of the piston in a direction toward the outside. The "one-way seal" herein means that the gap is sealed only in the outward direction, and in this case, one-way sealing may be achieved by using a lip seal such as a U-shaped seal or a V-shaped seal.

In one possible implementation, the piston valve further includes a driving mechanism for driving the piston to move in the axial direction, the driving mechanism being one of a manual operation mechanism, an electromagnetic driving mechanism, a pneumatic driving mechanism, a hydraulic driving mechanism, and an electro-hydraulic driving mechanism; and, electromagnetic drive mechanism includes still iron, moves the iron, connects still iron with move the iron's elastic component and set up move the iron with still iron outlying solenoid, move the iron with the piston is connected, wherein: when the electromagnetic coil is not electrified, the moving iron and the static iron are arranged at intervals, and the piston is positioned at the first position; when the electromagnetic coil is electrified, the moving iron and the static iron are magnetized, so that the moving iron drives the piston to move towards the static iron and compress the elastic piece, and the piston is located at the second position.

That is, in this implementation, the piston may be driven to move in the axial direction in a variety of manners, where when the piston is driven to move by the electromagnetic driving mechanism, the piston valve is an electromagnetic valve, the static iron and the moving iron are disposed at intervals when the electromagnetic coil is not energized, the piston is located at the first position, the static iron and the moving iron are magnetized by the electromagnetic coil when the electromagnetic coil is energized, the moving iron moves toward the static iron under the action of suction force, and drives the piston to move until dynamic and static contact occurs, and at this time the piston is located at the second position, thereby realizing movement of the piston between the first position and the second position.

In one possible implementation, the lip seal includes one of a U-shaped seal, a V-shaped seal, and a Y-shaped seal. It will be appreciated that other lip seals capable of performing similar functions, or other sealing rings or other sealing structures capable of performing similar functions, may be selected as desired.

In a second aspect, an embodiment of the present application provides a vehicle including: the piston valve provided in the first aspect and provided with a first fluid outlet and a second fluid outlet; a brake master cylinder in communication with the fluid inlet of the piston valve; a wheel and a brake cylinder in communication with the first fluid outlet of the piston valve to provide braking force to brake the wheel upon receipt of fluid; a pedal feel simulator in communication with the second fluid outlet of the piston valve to simulate a pedaling force upon receipt of the fluid; wherein: when the brake master cylinder is at the first position, the brake master cylinder is in bidirectional conduction with the brake wheel cylinder through the first reversing mechanism; the brake master cylinder is in one-way conduction with the pedal feel simulator through the second reversing mechanism; when the brake master cylinder is at the second position, the brake master cylinder is in one-way conduction with the brake wheel cylinder through the first reversing mechanism; the brake master cylinder and the pedal feel simulator are conducted in a bidirectional mode through the second reversing mechanism.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The drawings that accompany the detailed description can be briefly described as follows.

FIG. 1A is a schematic illustration of a vehicle brake system in a first operating position;

FIG. 1B is a schematic illustration of the braking system of FIG. 1A in a second operating position;

FIG. 1C is a schematic and actual block diagram of a check valve in the brake system shown in FIG. 1A;

fig. 2 is a schematic cross-sectional view of a piston valve according to a first embodiment of the present application;

FIG. 3A is an exemplary schematic diagram of the piston valve shown in FIG. 2;

FIG. 3B is another exemplary schematic diagram of the piston valve shown in FIG. 2;

FIG. 3C is a schematic illustration of yet another exemplary configuration of a piston of the piston valve shown in FIG. 2;

fig. 4 is a schematic cross-sectional view of a piston valve according to a second embodiment of the present application;

FIG. 5A is an exemplary schematic diagram of the piston valve shown in FIG. 4;

FIG. 5B is another exemplary schematic diagram of the piston valve shown in FIG. 4;

fig. 5C is a schematic view of still another exemplary structure of a piston of the piston valve shown in fig. 4.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

In the description of the present application, the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or by an abutting or integral connection; the specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a particular feature, structure, material, or characteristic may be combined in any suitable manner in one or more embodiments or examples.

In order to solve the safety and reliability problems of EMB, a hybrid braking system based on hydraulic and electronic machinery is formed. The hybrid braking system is described in detail below in conjunction with fig. 1A, 1B, and 1C.

Fig. 1A is a schematic illustration of a brake system of a vehicle in a first operating position. FIG. 1B is a schematic illustration of the braking system of FIG. 1A in a second operating position. As shown in fig. 1A and 1B, the vehicle includes a pedal assembly 1, a hydraulic assembly 2, a steering assembly 3, a front wheel assembly 4, a rear wheel assembly 5, a pedal feel simulator 6, and a first electronic control unit ECU7. The pedal assembly 1 may include a brake pedal 101 and a pedal travel sensor 102. The hydraulic assembly 2 may include a reservoir 201, a master cylinder 202, and an input pushrod 203. The pedal travel sensor 102 is mounted on the brake pedal 101, or the pedal travel sensor 102 is mounted on the input pushrod 203. The front wheel assembly 4 may include two front wheels 401 and a first EMB brake actuator 402. A first EMB brake actuator 402 is mounted on each of the two front wheels 401. The rear wheel assembly 5 comprises two rear wheels 501 and a second EMB brake actuator 502, the second EMB brake actuator 502 being mounted to each of the two rear wheels 501.

As shown in fig. 1A, in the first working position, the vehicle is in a completely disabled condition, when the driver steps on the pedal 101, the input push rod 203 is displaced under the action of the pedal assembly 1, so that the brake fluid in the brake master cylinder 202 of the hydraulic assembly 2 flows into the brake wheel cylinder of the first EMB actuator 402 of the front wheel assembly 4 through the reversing assembly 3, and the brake wheel cylinder provides braking force for the front wheel 401 under the driving of the brake fluid.

As shown in fig. 1B, in the second operating position, when the vehicle is in a normal operating condition or a non-complete failure condition, the input push rod 203 is displaced under the action of the pedal assembly 1 when the driver steps on the pedal 101, so that the brake fluid in the hydraulic assembly 2 flows into the pedal feel simulator 6 through the reversing assembly 3, and the pedal feel simulator 6 is used for generating a feedback force of the pedal assembly, so that the driver can easily perceive and control the magnitude of the braking force applied. In addition, the first ECU7 controls the front wheel assembly 4 and the rear wheel assembly 5 to provide braking force according to the acquired braking signal.

In the above hybrid brake system, the reversing assembly 3 may be a two-position three-way electromagnetic valve, that is, the two-position three-way electromagnetic valve 3 may be used as a guiding mechanism for the output hydraulic pressure of the brake master cylinder 202, so as to switch the brake master cylinder 202 between being conducted with the front wheel assembly 4 and being conducted with the pedal feel simulator 6. When the electricity is normal (namely, the second working position), the driver steps on the pedal 101, the hydraulic pressure in the brake master cylinder 202 is led into the pedal feel simulator 6 through the two-position three-way electromagnetic valve, and a force and displacement feedback is given to the driver; when the electric failure (i.e., the first operating position), the driver steps on the pedal 101, and the hydraulic two-position three-way solenoid valve in the master cylinder 202 is directed to the two front wheel brakes 401, resulting in emergency backup braking.

In addition, as shown in fig. 1A and 1B, the brake system may further include a check valve 8 and a check valve 9, the check valve 8 being provided on a pipe between the hydraulic assembly 2 and the front wheel assembly 4, and a direction in which the check valve 8 is conducted being a direction in which the front wheel assembly 4 flows toward the hydraulic assembly 2. A check valve 9 is provided on a pipe between the hydraulic pressure unit 2 and the pedal feel simulator 6, and a conduction direction of the check valve 9 is a direction from the pedal feel simulator 6 to the hydraulic pressure unit 2. In this way, when the brake pedal 101 is released in the first working position, the fluid in the brake cylinder of the first EMB actuator 402 can flow back to the brake master cylinder 202 through the hydraulic component 2, and the check valve 8 can assist the system to quickly release pressure; in the second operating position, when the brake pedal 101 is released, the fluid in the pedal feel simulator 6 can flow back to the master cylinder 202 through the hydraulic assembly 2, and the check valve 9 can assist the system in rapid pressure relief.

In addition, the check valve 8 ensures that the pressure in the brake cylinder of the first EMB actuator 402 of the front wheel assembly 4 is not greater than the pressure in the hydraulic assembly 2, i.e., the high pressure fluid in the brake cylinder can flow back to the hydraulic assembly 2 when the pressure in the hydraulic assembly 2 decreases, whether in the first operating position or the second operating position; the non-return valve 9 ensures that the high pressure fluid in the pedal feel simulator 6 is able to flow back to the hydraulic assembly 2 when the pressure in the steady state pedal feel simulator 6 is not greater than the pressure in the hydraulic assembly 2, i.e. the pressure in the hydraulic assembly 2 is reduced. That is, the check valve 8 and the check valve 9 can ensure so-called "driver intention first", that is, when the driver releases the pedal in any case and the hydraulic pressure in the master cylinder 202 decreases, the hydraulic pressure in the wheel cylinders of the first EMB actuator 402 of the front wheel assembly 4 may flow back through the check valve 8, and the hydraulic pressure in the pedal feel simulator 6 may flow back through the check valve 9, thereby ensuring that the pressure thereof follows the driver intention.

Fig. 1C is a schematic diagram and an actual structural view of a check valve in the brake system shown in fig. 1A. In fig. 1C, fig. 1 (a) is two schematic diagrams of the check valve, and fig. 1 (b 2), fig. 3 (b 4) are four practical structural diagrams of the check valve. As shown in fig. 1C, the check valve is generally formed by arranging a ball or cone at the conical nozzle, and fluid can only flow from the top of the cone to the bottom of the cone, otherwise, the fluid can push the ball or cone to press the conical nozzle, and the fluid is locked to form unidirectional circulation. The one-way valve is typically present as a single component.

As can be seen from fig. 1A, fig. 1B and fig. 1C, the above solution needs to separately set a check valve outside the reversing assembly 3, such as a two-position three-way valve, which results in more parts and flow channels, higher leakage risk, adverse cost reduction, and larger volume, and adverse miniaturization.

In view of this, embodiments of the present application provide a piston valve and a vehicle. The fluid inlet and the fluid outlet of the piston valve can be conducted in one way or in two directions through the reversing mechanism, the function of integrating the check valve on the piston valve is realized, the single check valve is avoided, the high-pressure fluid at the fluid outlet can flow back to the fluid inlet when the pressure at the fluid inlet is reduced, the pressure at the fluid outlet in a stable state can not be larger than the pressure at the fluid inlet, the probability of danger is reduced, the number of parts is reduced, the leakage risk is reduced, the reliability is improved, the cost is reduced, and the miniaturization is facilitated. The piston valve can comprise a fluid inlet, a fluid outlet and a reversing mechanism, and is a two-position two-way valve; alternatively, the piston valve may comprise one fluid inlet, two fluid outlets and two reversing mechanisms, in which case the piston valve is a two-position three-way valve. The number of the piston valves and the number of the openings can be increased as required, for example, the piston valves can be three-position five-way valves, and the reversing mechanism can be correspondingly increased.

Fig. 2 is a schematic cross-sectional view of a piston valve according to a first embodiment of the present application. As shown in fig. 2, the piston valve includes a cylinder 1, a piston 2, and a reversing mechanism 3. The piston 2 is provided in the cylinder 1 and is movable in the axial direction in the cylinder 1. The annular side wall of the cylinder body 1 is provided with a fluid inlet R and a fluid outlet C at intervals along the axial direction, namely the piston valve is a two-position two-way valve. Also, the fluid inlet R may be disposed along the entire circumferential direction of the cylinder 1, and the fluid outlet C may be disposed along the entire circumferential direction of the cylinder 1, i.e., the fluid inlet R and the fluid outlet C may be disposed around the outer wall of the cylinder 1, and in this case, the piston valve further includes a valve seat (not shown in fig. 2) provided with a plurality of passages communicating with the fluid inlet R and the fluid outlet C, respectively.

In fig. 2, the axial positions of the fluid inlets R in the entire circumferential direction on the cylinder 1 are the same, and the axial positions of the fluid outlets C in the entire circumferential direction on the cylinder 1 are the same, i.e., the fluid inlets R and the fluid outlets C may be disposed around the outer circumference of a "cross section" of the cylinder 1, which is perpendicular to the central axis of the cylinder 1, respectively. Of course, it will be appreciated that the configuration of the fluid inlet R and the fluid outlet C may also be varied as desired. For example, the fluid inlet R and the fluid outlet C are arranged along part of the circumferential direction. For example, if necessary, the fluid inlet R may be designed so that the axial positions of the different portions in the circumferential direction on the cylinder 1 are different, and the fluid outlet C may be designed so that the different portions in the circumferential direction are different in the axial positions of the cylinder 1, that is, the fluid inlet R and the fluid outlet C may be respectively disposed around the outer periphery of a "transverse cross section" of the cylinder 1, which is at an angle to the above-mentioned "cross section" and is not perpendicular to the central axis of the cylinder 1.

Here, description will be mainly made taking as an example "the fluid inlet R and the fluid outlet C are respectively provided on the cylinder block 1 in the entire circumferential direction and the axial positions of the different portions each in the circumferential direction are the same".

As shown in fig. 2, the reversing mechanism 3 may be disposed at a gap of the cylinder 1 and the piston 2 around the circumferential direction of the piston 2, the reversing mechanism 3 being located between the fluid inlet R and the fluid outlet C in the axial direction and communicating with the fluid outlet C. The reversing mechanism 3 is capable of switching between a unidirectional conducting state and a bidirectional conducting state when the piston 2 moves in the axial direction.

In the unidirectional conducting state, the reversing mechanism 3 is capable of unidirectional sealing the circumferential gap between the cylinder 1 and the piston 2, i.e. the reversing mechanism 3 unidirectional seals the gap in the entire circumferential direction, to prevent fluid flow from the fluid inlet R through the reversing mechanism 3 to the fluid outlet C and to enable fluid flow from the fluid outlet C back through the reversing mechanism 3 to the fluid inlet R.

In the bi-directional conducting state, the reversing mechanism 3 is capable of flowing fluid from the fluid inlet R through the reversing mechanism 3 to the fluid outlet C or capable of reversing fluid from the fluid outlet C through the reversing mechanism 3 back to the fluid inlet R. It should be noted that, the "bidirectional conduction state" herein means that fluid can flow from the fluid inlet R to the fluid outlet C through the reversing mechanism 3 in the first period, and fluid can flow back from the fluid outlet C to the fluid inlet R through the reversing mechanism 3 in the second period, that is, conduction in different directions of the same channel can be achieved in different periods.

Wherein the fluid may be a liquid or a gas, etc. In addition, since the reversing mechanism 3 is in either the unidirectional or bidirectional conductive state, the reversing mechanism 3 (specifically, the annular groove passage 34 of the reversing mechanism 3, which will be described below) is in communication with the fluid outlet C, so that it is ensured that the liquid at the fluid outlet C can flow back to the fluid inlet R through the reversing mechanism 3, i.e., when the pressure at the fluid inlet R decreases, the high-pressure fluid at the fluid outlet C can flow back to the fluid inlet R, so that the pressure at the steady-state fluid outlet C is not greater than the pressure at the fluid inlet R, and the probability of occurrence of a hazard is reduced.

With continued reference to fig. 2, the reversing mechanism 3 may include a ring groove 31, a one-way seal 32, an annular outer wall 33, and a ring groove channel 34. A ring groove 31 is provided on one of the inner wall of the cylinder 1 and the outer wall of the piston 2, and a one-way seal 32 is provided in the ring groove 31. The annular outer wall 33 and the annular groove passage 34 are adjacently provided on the other of the inner wall of the cylinder 1 and the outer wall of the piston 2, and the fluid inlet R and the annular groove passage 34 are located on both sides of the annular outer wall 33 in the axial direction, and the fluid outlet C communicates with the annular groove passage 34.

In fig. 2 and fig. 4, which will be described later, an annular outer wall 33 and an annular groove passage 34 are provided adjacently on the outer wall of the piston 2, an annular groove 31 is provided on the inner wall of the cylinder 1, and a one-way seal 32 may be provided in the annular groove 31. It will be appreciated that the annular outer wall and annular groove channel may be provided adjacent to the inner wall of the cylinder 1, while the annular groove is provided on the outer wall of the piston 2, and the one-way seal 32 may be provided in the annular groove at the outer wall of the piston 2.

As shown in fig. 2, the reversing mechanism 3 is in a two-way conduction state, and the one-way seal 32 is offset from the annular outer wall 33 and corresponds to the annular groove channel 34. Fluid entering the gap between the cylinder 1 and the piston 2 from the fluid inlet R can flow through the annular groove passage 34 in the direction from the fluid inlet R to the annular groove passage 34 to flow to the fluid outlet C; or fluid that enters the gap between the cylinder 1 and the piston 2 from the fluid outlet C can flow through the annular groove passage 34 in the direction from the annular groove passage 34 to the fluid inlet R to flow back to the fluid inlet R. That is, when the one-way seal 32 is in contact with the annular groove passage 34, the fluid can achieve two-way flow through the annular groove passage 34 at the one-way seal 32.

In addition, in the bidirectional conduction state shown in fig. 2, when the piston 2 moves in the axial direction so that the one-way seal 32 is in contact with the annular outer wall 33, the reversing mechanism 3 is in the one-way conduction state. At this time, the one-way seal 32 can seal the gap in the direction from the fluid inlet R to the annular groove passage 34, the fluid that enters the gap between the cylinder 1 and the piston 2 from the fluid inlet R cannot flow to the fluid outlet C through the reversing mechanism 3, and the one-way seal 32 can flow the fluid that enters the gap between the cylinder 1 and the piston 2 through the fluid outlet C through the gap in the direction from the annular groove passage 34 to the fluid inlet R to flow back to the fluid inlet R. That is, one-way sealing/one-way conduction can be achieved when the one-way seal 32 is in contact with the annular outer wall 33, fluid at the fluid inlet R can be prevented from flowing through the one-way seal 32, and fluid at the fluid outlet can be allowed to flow back to the fluid inlet R through the gap between the one-way seal 32 and the annular outer wall 33.

The unidirectional seal 32 may comprise a lip seal, the lip of which faces the side of the fluid inlet R. The lip side, i.e. the side on which the fluid inlet R is located; the opposite side of the lip, i.e. the side on which the fluid outlet C is located. In this way, when the unidirectional sealing member 32 is in corresponding contact with the annular outer wall 33, the lip expands outwards when the pressure of the fluid on the lip side is greater than the pressure of the fluid on the opposite side of the lip, so that the lip of the lip seal ring can be abutted against the annular outer wall 33, and the gap can be sealed along the direction from the fluid inlet R to the annular groove channel 34. And when the fluid pressure at the lip side is smaller than that at the opposite side of the lip, the lip contracts, so that the lip of the lip-shaped sealing ring is separated from the annular outer wall 33 to form a gap, and fluid flows from the opposite side of the lip to the lip side through the gap, thereby realizing unidirectional sealing or unidirectional conduction. And, in the case where the one-way seal 32 corresponds to the annular groove passage 34, when the pressure of the fluid on the lip side is greater than the pressure of the fluid on the opposite side of the lip, the fluid can flow from the lip side to the opposite side of the lip through the annular groove passage 34; when the pressure of the fluid on the lip side is smaller than the pressure of the fluid on the opposite side of the lip, the fluid can flow from the opposite side of the lip to the lip side through the annular groove passage 34, thereby achieving bidirectional communication. Wherein the lip seal may comprise one of a U-shaped seal, a V-shaped seal, and a Y-shaped seal. In fig. 2 and 4, the one-way seal 32 is a U-shaped seal ring. It will be appreciated that other lip seals, other types of seals or other sealing arrangements that perform similar functions may be selected as desired.

The piston of the traditional piston valve is provided with a groove and a high point, the high point is provided with an O-shaped sealing ring, the cylinder body matched with the piston is also provided with the groove and the high point, and the high point of the cylinder body is not required to be provided with the sealing ring. When the high point of the piston is aligned with the high point of the cylinder body, the O-shaped sealing ring can seal the circumferential gap between the cylinder body and the piston, so that the hydraulic pressure is isolated; when the driving mechanism pushes the piston to move along the axial direction, when the high point of the piston is staggered from the high point of the cylinder body, the O-shaped sealing ring cannot seal the circumferential gap between the cylinder body and the piston, and liquid can be conducted. Because the O-shaped sealing ring needs interference fit to seal, namely needs precompression during sealing, the motion resistance is larger, further, the size of the O-shaped sealing ring along the axial direction is larger than that of the lip-shaped sealing ring, and after the O-shaped sealing ring is precompressed, the size of the O-shaped sealing ring along the axial direction is further increased, so that the motion stroke of the piston 2 during switching between a sealing state and a conducting state is larger, the power consumption is higher, a driving mechanism with higher power is needed, and the size is larger because a matched spring and an electromagnetic valve are larger when an electromagnetic driving mechanism is adopted, and the miniaturization is not facilitated.

The unidirectional seal 32 in the reversing mechanism 3 of the embodiment of the application may be a lip seal. The lip of the lip-shaped sealing ring deforms under the action of hydraulic pressure, so that the lip is tightly attached to the sealing surface. The higher the hydraulic pressure, the tighter the lip and the sealing surface are stuck, and the sealing lip has certain automatic compensation capability after being worn. The lip seal ring has no precompression, so that the movement resistance is small, the sliding resistance of the piston valve is reduced, and meanwhile, the lip seal ring is sealed by virtue of the lip, and the axial size is small, so that the movement stroke of the piston valve is reduced, the power consumption of a driving mechanism for driving the piston 2 to move is reduced, the volume can be reduced, and the miniaturization is facilitated.

In addition, in order to ensure that the fluid does not flow out from both ends of the piston 2 along the gap between the piston 2 and the piston, sealing rings may be provided at both ends of the piston 2 to seal. With continued reference to fig. 2, the piston valve may also include a first seal M1 and a second seal M2. Two annular grooves can be formed in the inner wall of the cylinder body 1, and the first sealing ring M1 and the second sealing ring M2 are respectively arranged in the two annular grooves. At this time, the ring groove 31 accommodating the one-way seal 32 is located between the first seal ring M1 and the second seal ring M2 in the axial direction.

In particular, the first sealing ring M1 may be located at a first end of the piston 2 and is capable of sealing a circumferential gap between the cylinder 1 and the piston 2 at the first end of the piston 2 in a direction from the second end to the first end of the piston 2. The second sealing ring M2 is located at the second end of the piston 2 and is capable of sealing a circumferential gap between the cylinder 1 and the piston 2 at the second end of the piston 2 in a direction from the first end to the second end of the piston 2. The fluid inlet R, the fluid outlet C, and the reversing mechanism 3 are located between the first seal ring M1 and the second seal ring M2 in the axial direction.

The first seal ring M1 and the second seal ring M2 need to seal the gap at both ends of the piston 2 at least in the direction toward the outside, respectively. I.e. the first sealing ring M1 and the second sealing ring M2 function to block fluid flow out of the piston valve. Here, "outward direction" refers to a direction away from the fluid inlet in the axial direction at the end of the piston 2. For example, at a first end of the piston 2, "outward direction" refers to the direction of the second end of the fluid inlet/piston 2 to the first end of the piston 2; at the second end of the piston 2, the "outward direction" refers to the direction of the first end of the fluid inlet/piston 2 to the second end of the piston 2.

The first sealing ring M1 and the second sealing ring M2 may have, but are not limited to, the following two ways:

Mode 1—the first seal ring M1 and the second seal ring M2 are lip-shaped seal rings, and the lip-shaped seal rings can seal a gap unidirectionally along a direction from a lip side to an opposite side of the lip. As shown in fig. 2 and fig. 4 to be described later, the lip seal as the first seal ring M1 has an opening toward the side of the fluid inlet R, so that the circumferential gap between the cylinder 1 and the piston 2 can be sealed in the direction from the lip side, i.e., the fluid inlet R, to the opposite side, i.e., the first end of the piston 2; the lip seal as the second seal M1 has an opening facing the side of the fluid inlet R, so that the circumferential gap between the cylinder 1 and the piston 2 can be sealed in the direction from the lip side, i.e., the fluid inlet R, to the opposite side, i.e., the second end of the piston 2.

The lip seal ring has no precompression, so that the movement resistance is small, the sliding resistance of the piston valve is reduced, and meanwhile, the lip seal ring is sealed by the lip, and the axial size is small, so that the movement stroke of the piston valve is reduced, and the power consumption of a driving mechanism for driving the piston 2 to move is reduced.

Mode 2—the first seal ring M1 and the second seal ring M2 are both O-ring seals, wherein the O-ring seals the gap in both directions from the first end of the piston 2 to the second end of the piston 2 and from the second end of the piston 2 to the first end of the piston 2. That is, the first and second sealing rings M1 and M2 may bidirectionally seal the circumferential gap between the cylinder 1 and the piston 2 in the axial direction at both ends of the piston 2, respectively, and herein, "bidirectionally seal" means a direction from the first end to the second end of the piston 2 and a direction from the second end to the first end of the piston 2, and at this time, the first and second sealing rings M1 and M2 may use O-rings to realize bidirectionally sealing.

In addition to the above two modes, the first seal ring M1 may be an O-ring seal, and the second seal ring M2 may be a lip-ring seal. Or the first sealing ring M1 is a lip-shaped sealing ring, and the second sealing ring M2 is an O-shaped sealing ring.

Further, the piston valve may further include a driving mechanism for driving the piston 2 to move in the axial direction, the driving mechanism being one of a manual operation mechanism, an electromagnetic driving mechanism 4, a pneumatic driving mechanism, a hydraulic driving mechanism, and an electro-hydraulic driving mechanism. The electromagnetic drive mechanism 4 is mainly described herein as an example. The piston valve may be a solenoid valve at this time. As shown in fig. 2 and fig. 4 to be described later, the electromagnetic driving mechanism 4 may include a stationary iron 41, a moving iron 42, an elastic member 43 connecting the stationary iron 41 and the moving iron 42, and an electromagnetic coil 44 disposed at the periphery of the moving iron 42 and the stationary iron 41, the moving iron 42 being connected to the piston 2, for example, the moving iron 42 and the piston 2 being fixed together by a tight fit of a hole shaft, the moving iron 42 being moved to pull the piston 2 up and down in the cylinder 1.

The elastic member 43 may be a spring, one end of which is connected to the stationary iron 41 and the other end of which is connected to the moving iron 42. As shown in fig. 2, when the electromagnetic coil 44 is not energized, the moving iron 42 and the static iron 41 are arranged at intervals, the piston 2 is located at the first position, and the elastic member 43 can be in a compressed state; when the electromagnetic coil 44 is electrified, the moving iron 42 and the static iron 41 are magnetized, and under the action of attractive force generated between the moving iron 42 and the static iron 41, the moving iron 42 drives the piston 2 to move towards the static iron 41 and further compresses the elastic piece 43 until the interval between the moving iron 42 and the static iron 41 disappears, namely the moving iron 42 is contacted with the static iron 41, and the piston 2 is positioned at the second position. The interval is the travel of the moving iron 42.

In addition, in order to allow the liquid at the fluid inlet R to flow into the gap between the cylinder 1 and the piston 2 as soon as possible, the size of the gap at the fluid inlet R may be increased, and in particular, an annular passage T may be provided on the other of the inner wall of the cylinder 1 and the outer wall of the piston 2. As shown in fig. 2, the ring groove 31 is provided on the inner wall of the cylinder 1, and the annular passage T may be provided on the outer wall of the piston 2. Or if the ring groove 31 is provided on the outer wall of the piston 2, the annular passage T may be provided on the inner wall of the cylinder 1. Also, the fluid inlet R may be in communication with an annular channel T, which may be the same or different from the annular channel 34 of the reversing mechanism 3.

Fig. 3A is a schematic view of an exemplary structure of a piston of the piston valve shown in fig. 2. As shown in fig. 3A, the annular groove passages 34 are identical in structure to the annular passage T, and are continuous grooves extending in the circumferential direction. Thus, the processing difficulty is low, and the time is saved.

Fig. 3B is another exemplary structural schematic of a piston of the piston valve shown in fig. 2. Unlike the piston 2 shown in fig. 3A, in the piston 2 shown in fig. 3B, the annular groove passage 34 is of an intermittent groove design in the circumferential direction, and specifically, the annular groove passage 34 includes a plurality of groove bodies G arranged at intervals in the circumferential direction around the other of the inner wall of the cylinder 1 and the outer wall of the piston 2, wherein the plurality of groove bodies G may be arranged at intervals in the circumferential direction or may be unevenly arranged. When the unidirectional sealing element 32 corresponds to the annular groove channel 34, the outer wall W between the adjacent groove bodies G can support and contact the unidirectional sealing element 32, namely, the lip edge of the lip-shaped sealing ring can be reliably supported, so that the lip-shaped sealing ring can realize on-off of liquid under the condition that the lip-shaped sealing ring is not remarkably deformed, the unidirectional sealing element 32 can be effectively prevented from overturning, and the service life of the lip-shaped sealing ring is prolonged. In addition, in fig. 3B, the annular channel T is still a continuous groove extending in the circumferential direction.

Further, the dimension of the groove body G in the axial direction may be larger than the dimension in the circumferential direction, for example, the groove body G may be an elongated groove, and the length of the elongated groove is in the axial direction and is consistent with the flow direction of the fluid, so that more groove bodies G may be disposed in the circumferential direction, so that the fluid may flow from the more groove bodies G separately in a divided manner, and the stress may be more balanced. In addition, the dimension of the groove body G in the axial direction may be smaller than the dimension in the circumferential direction, so that the groove body G can accommodate more fluid and the fluid can pass through the groove body G faster. Of course, the dimension of the groove G in the axial direction may be equal to the dimension in the circumferential direction.

In addition, the longitudinal section or cross section of the groove body G is arc-shaped. The "cross section of the groove G" refers to a transverse cross section perpendicular to the central axis of the piston 2. The "longitudinal section of the groove G" refers to a longitudinal section through the central axis of the piston 2. In addition, the arc may be distant from the central axis of the piston 2 along both ends of the bending direction with respect to the middle of the arc. Namely, the arc is bent away from the central axis of the piston 2, so that the middle space of the groove body G is larger, the spaces at the two ends are smaller, and the processing and the manufacturing are convenient. And when the section of cell body G is the arc, the flow channel that forms is comparatively smooth, makes things convenient for fluid to get into cell body G and follow cell body G outflow, and the fluid can pass through more smoothly promptly, is difficult for making the fluid remain, is favorable to accelerating fluid velocity. It is understood that the cross section of the tank G may be other shapes, for example, the cross section of the tank G is rectangular.

Fig. 3C is a schematic view of still another exemplary structure of a piston of the piston valve shown in fig. 2. The difference from the piston 2 shown in fig. 3B is that in the piston 2 shown in fig. 3C, the annular passage T has the same structure as the annular groove passage 34, and is designed as an intermittent groove in the circumferential direction.

According to the piston valve provided by the embodiment of the application, the fluid inlet R and the fluid outlet C can be conducted in one way or two ways through the reversing mechanism 3, so that the function of integrating the check valve on the piston valve is realized, the high-pressure fluid at the fluid outlet C can flow back to the fluid inlet R when the pressure at the fluid inlet R is reduced, the pressure at the fluid outlet C in a stable state is not greater than the pressure at the fluid inlet R, the probability of danger is reduced, the adoption of a single check valve is avoided, the number of parts and the number of flow channels are reduced, the leakage risk is reduced, the reliability is improved, the cost is reduced, and the miniaturization is facilitated.

In addition, the unidirectional sealing element 32 may be a lip sealing ring, and the lip sealing ring has no precompression, small movement resistance, and reduces the sliding resistance of the piston valve, and meanwhile, the lip sealing ring relies on lip sealing, so that the axial dimension is small, the movement stroke of the piston valve is reduced, the power consumption of a driving mechanism for driving the piston 2 to move is reduced, the volume can be reduced, and the miniaturization is facilitated.

The piston 2 can adopt the design scheme of an intermittent groove, wherein the intermittent groove refers to that a groove is intermittent in the circumferential direction, a continuous annular groove is not formed, and a complete annular ring which is arranged adjacent to the intermittent groove, namely, an annular outer wall and a lip-shaped sealing ring such as a U-shaped sealing ring lip are matched to form one-way sealing to block fluid such as liquid flow in one way; when the U-shaped sealing ring lip is attached to the intermittent groove, liquid can flow bidirectionally from the groove. The intermittent groove can ensure that the piston 2 can smoothly slide bidirectionally relative to the U-shaped sealing ring, and can reliably support the lip edge of the lip-shaped sealing ring, so that the lip-shaped sealing ring can realize on-off of liquid under the condition that the lip-shaped sealing ring does not generate remarkable deformation, the unidirectional sealing piece 32 can be effectively prevented from overturning, and the service life of the lip-shaped sealing ring is prolonged. The steps of the continuous groove are easy to cause the overturning and damage of the rubber lip edge of the continuous groove when the continuous groove slides reversely relative to the U-shaped sealing ring.

Fig. 4 is a schematic cross-sectional view of a piston valve according to a second embodiment of the present application. The difference from the piston valve shown in fig. 2 is that in the piston valve shown in fig. 4, two fluid outlets C are provided on the cylinder 1, the fluid inlet R is located between the two fluid outlets C in the axial direction, the two fluid outlets C are a first fluid outlet C1 and a second fluid outlet C2, the piston valve is a two-position three-way valve, the piston valve comprises two reversing mechanisms 3, and the two reversing mechanisms 3 are a first reversing mechanism 3a and a second reversing mechanism 3b. The first reversing mechanism 3a is located between the fluid inlet R and the first fluid outlet C1 along the axial direction and is in communication with the first fluid outlet C1, specifically, the annular groove channel 34 of the first reversing mechanism 3a is in communication with the first fluid outlet C1, and the first reversing mechanism 3a can realize unidirectional or bidirectional communication between the fluid inlet R and the first fluid outlet C1, so that when the pressure at the fluid inlet R is reduced, the high-pressure fluid at the first fluid outlet C1 can flow back to the fluid inlet R, so that the pressure at the first fluid outlet C1 is not greater than the pressure at the fluid inlet R in a steady state. The second reversing mechanism 3b is located between the fluid inlet R and the second fluid outlet C2 along the axial direction and is in communication with the second fluid outlet C2, specifically, the annular groove channel 34 of the second reversing mechanism 3b is in communication with the second fluid outlet C2, and the second reversing mechanism 3b can realize unidirectional or bidirectional communication between the fluid inlet R and the second fluid outlet C2, so that when the pressure at the fluid inlet R is reduced, the high-pressure fluid at the second fluid outlet C2 can flow back to the fluid inlet R, so that the pressure at the second fluid outlet C2 is not greater than the pressure at the fluid inlet R in a steady state.

The piston 2 is movable between a first position and a second position. In the first position, the first reversing mechanism 3a is in a bidirectional conduction state, and the second reversing mechanism 3b is in a unidirectional conduction state; in the second position, the first reversing mechanism 3a is in a unidirectional conduction state, and the second reversing mechanism 3b is in a bidirectional conduction state. I.e. the first 3a and second 3b commutation mechanisms are in different conducting states at the first and second positions.

The form of the drive mechanism for driving the piston 2 to move in the axial direction can be seen from the description of the piston valve of the first embodiment. As shown in fig. 4, when the electromagnetic driving mechanism is used to drive the piston 2 to move, the elastic member 43 pushes the moving iron 42 and the piston 2 to the lowest position when the electromagnetic coil 44 is not energized, the piston 2 is located at the first position, the moving iron 41 and the moving iron 42 are magnetized by the electromagnetic coil 44, the moving iron 42 is moved towards the moving iron 41 by electromagnetic force, and the piston 2 is driven to move until the moving iron 42 contacts the moving iron 41, and the piston 2 can move to the second position, so that the piston 2 can move between the first position and the second position.

With continued reference to fig. 4, in the piston valve of the second embodiment of the present application, the annular passage T communicating with the fluid inlet R may be located between the annular outer wall 33 of the first reversing mechanism 3a and the annular outer wall 33 of the second reversing mechanism 3 b. And the annular channel T is the same as or different from the annular channel 34 of the reversing mechanism 3.

Fig. 5A is a schematic view of an exemplary structure of a piston of the piston valve shown in fig. 4. As shown in fig. 5A, the annular groove passage 34 of the first reversing mechanism 3a and the annular groove passage 34 of the second reversing mechanism 3b are each continuous grooves extending in the circumferential direction, like the annular passage T. Thus, the processing difficulty is low, and the time is saved.

Fig. 5B is another exemplary structural schematic of a piston of the piston valve shown in fig. 4. The difference from the piston 2 shown in fig. 5A is that in the piston 2 shown in fig. 5B, the annular groove passage 34 of the first reversing mechanism 3a and the annular groove passage 34 of the second reversing mechanism 3B are of an intermittent groove design, and for details of the intermittent groove, reference is made to the description relating to fig. 3B. In addition, in fig. 5B, the annular channel T is still a continuous groove extending in the circumferential direction.

Fig. 5C is a schematic view of still another exemplary structure of a piston of the piston valve shown in fig. 4. The difference from the piston 2 shown in fig. 5B is that in the piston 2 shown in fig. 5C, the annular passage T has the same structure as the annular groove passage 34, and is designed as an intermittent groove in the circumferential direction.

The application scenario of the piston valve according to the second embodiment of the present application is that a two-position three-way valve is required to selectively guide one hydraulic input to two output passages, and when the pressure of the input passage is reduced, the high-pressure liquid at the two output passages can flow back to the input passage, so that the pressure of the two output passages in a steady state is not greater than the pressure of the input passage, wherein the input passage is connected to the fluid inlet, and the output passage is connected to the fluid outlet. Specifically, two check valves and two-position three-way valves are designed as a whole, two-position three-way valves are connected in parallel, the occurrence of single check valves is avoided, the pressure of two output ends/fluid outlets can flow back to an input end, namely, when the pressure of the fluid inlet is reduced, the high-pressure fluid at the fluid outlet can flow back to the fluid inlet, the pressure at the fluid outlet in a stable state can not be larger than the pressure at the fluid inlet, the probability of danger is reduced, the number of parts and the number of flow channels are reduced, the leakage risk is reduced, the reliability is improved, the cost is reduced, and the miniaturization is facilitated.

Furthermore, the embodiment of the application uses the lip-shaped sealing ring such as a U-shaped sealing ring to replace an O-shaped sealing ring, and uses the unidirectional conduction function of the lip-shaped sealing ring to replace a unidirectional valve so as to realize the function of connecting the two-position three-way valve with the unidirectional valve in parallel. The lip seal ring has no precompression, so that the movement resistance is small, the sliding resistance of the piston valve is reduced, and meanwhile, the lip seal ring is sealed by virtue of the lip, and the axial size is small, so that the movement stroke of the piston valve is reduced, the power consumption of a driving mechanism for driving the piston 2 to move is reduced, the volume can be reduced, and the miniaturization is facilitated.

The embodiment of the application also provides a vehicle which comprises a piston valve, a brake master cylinder, wheels, brake wheel cylinders and a pedal feel simulator. The piston valve of the vehicle may be the piston valve of the second embodiment of the present application described above. The master cylinder communicates with the fluid inlet R of the piston valve. The wheel cylinders communicate with the first fluid outlet C1 of the piston valve, and provide braking force to brake the wheels when fluid is received. The pedal feel simulator communicates with the second fluid outlet C2 of the piston valve, simulating a stepping force when receiving fluid.

In the first position, the brake master cylinder is conducted with the brake wheel cylinder in a bidirectional manner through the first reversing mechanism 3 a; the brake master cylinder and the pedal feel simulator are conducted in one direction through the second reversing mechanism 3 b. Thus, when the driver steps on the pedal, the fluid pressure in the brake master cylinder is increased, so that the fluid in the brake master cylinder sequentially enters the brake cylinder through the fluid inlet R, the first reversing mechanism 3a and the first fluid outlet C1 to apply braking force to the wheels; the unidirectional sealing piece 32 of the second reversing mechanism 3b unidirectional seals the gap between the piston 2 and the cylinder body 1, so that the fluid in the brake master cylinder can be prevented from passing, and the fluid cannot enter the pedal feel simulator; when the driver releases the pedal, the fluid pressure in the master cylinder decreases, and the fluid in the wheel cylinders can flow back to the master cylinder through the first fluid outlet C1, the first steering mechanism 3a, and the fluid inlet R in this order.

Specifically, as shown in fig. 4, in the first position, with respect to the first reversing mechanism 3a, the unidirectional seal 32, such as a U-shaped seal ring, in the ring groove 31 of the cylinder 1 is fitted with the intermittent groove, that is, the ring groove channel 34, and the unidirectional seal 32 does not circumferentially seal the gap between the piston 2 and the cylinder 1, and the high-pressure liquid in the master cylinder connected to the fluid inlet R can continue to flow through the intermittent groove at the piston 2, flow to the first fluid outlet C1, and enter the brake cylinder to form a backup brake. In addition, when the fluid pressure in the brake cylinder is higher than the fluid pressure in the master cylinder, the fluid in the brake cylinder may enter the cylinder 1 through the first fluid outlet C1 and flow back to the fluid inlet R through the one-way seal 32, and thus enter the master cylinder. With the second reversing mechanism 3b, the annular outer wall 33 on the piston 2 is sealed in one direction with the one-way seal 32, such as a U-shaped seal, in the annular groove 31 of the cylinder 1, and after the fluid in the master cylinder connected to the fluid inlet R enters the gap between the cylinder 1 and the piston 2, it cannot pass through the one-way seal 32 of the second reversing mechanism 3b to the second fluid outlet C2, and thus cannot enter the pedal feel simulator. However, when the fluid pressure in the pedal feel simulator is higher than the fluid pressure in the master cylinder, the fluid in the pedal feel simulator may enter the cylinder 1 through the second fluid outlet C2 and flow back to the fluid inlet R through the one-way seal 32, and thus enter the master cylinder.

When the piston valve is electrified, the braking force of the wheels can be provided by the first ECU shown in the figures 1A and 1B, and fluid in the brake master cylinder can be used for entering the pedal simulator to simulate the stepping force, at the moment, the piston 2 is positioned at the second position, and the brake master cylinder is in one-way conduction with the brake cylinder through the first reversing mechanism 3 a; the brake master cylinder and the pedal feel simulator are conducted in two directions through the second reversing mechanism 3 b. The driver steps on the pedal, the fluid pressure in the brake master cylinder is increased, so that the fluid in the brake master cylinder sequentially enters the pedal feel simulator through the fluid inlet R, the second reversing mechanism 3b and the second fluid outlet C2, and the one-way sealing piece 32 of the first reversing mechanism 3a seals the gap between the piston 2 and the cylinder body 1 in a one-way manner, so that the fluid in the brake master cylinder can be prevented from passing through, and the fluid cannot enter the brake wheel cylinder; the driver releases the pedal, the hydraulic pressure in the master cylinder decreases, and the fluid in the pedal feel simulator can flow back to the master cylinder through the second fluid outlet C2, the second reversing mechanism 3b, and the fluid inlet R in this order.

Specifically, in the second position, for the first reversing mechanism 3a, the annular outer wall 33 on the piston 2 and the one-way seal 32 such as a U-shaped seal ring are bonded to form a one-way seal, so that after the liquid in the brake master cylinder enters the cylinder 1 through the fluid inlet R, the liquid cannot flow to the first fluid outlet C1 through the first reversing mechanism 3a, and thus cannot enter the brake cylinder; however, when the fluid pressure in the brake cylinder is higher than the fluid pressure in the master cylinder, the fluid in the brake cylinder may enter the gap between the cylinder 1 and the piston 2 through the first fluid outlet C1 and flow back to the fluid inlet R through the one-way seal 32, and thus enter the master cylinder. For the second reversing mechanism 3b, the unidirectional sealing member 32, such as a U-shaped sealing ring, in the ring groove 31 of the cylinder 1 is attached to the intermittent groove, i.e., the ring groove channel 34, and after the high-pressure liquid in the master cylinder connected to the fluid inlet R enters the gap between the cylinder 1 and the piston 2, the high-pressure liquid can continue to flow through the intermittent groove at the piston 2, flow to the second fluid outlet C2, and enter the pedal feel simulator to form pedal feedback. In addition, when the fluid pressure in the pedal feel simulator is higher than the fluid pressure in the master cylinder, the fluid in the pedal feel simulator may enter the gap between the cylinder 1 and the piston 2 through the second fluid outlet C2, and flow back to the fluid inlet R through the one-way seal 32 of the second reversing mechanism 3b, and thus enter the master cylinder.

In summary, in the embodiment of the application, the lip-shaped sealing ring such as the U-shaped sealing ring is used to replace the O-shaped sealing ring, which plays a role in unidirectional conduction, avoids the split one-way valve, realizes the function of connecting the one-way valve in parallel on the piston valve, reduces the number of parts and the number of channels, reduces the leakage risk, improves the reliability, reduces the cost, and is beneficial to reducing the volume and realizing miniaturization. Further, the intermittent groove design not only can form a fluid, such as a liquid channel, but also can support the lip of the lip-shaped sealing ring, such as the U-shaped sealing ring, so that the on-off of the liquid is realized under the condition that no significant deformation occurs, the service life of the U-shaped sealing ring is prolonged, and the bidirectional movement of the piston relative to the U-shaped sealing ring is facilitated. In addition, the sealing is realized without using the height H of the whole U-shaped sealing ring, and only the smooth section matched sealing between the lip edge and the intermittent groove is used, so that the friction resistance can be reduced, the stroke of the electromagnetic valve is smaller, and the lip-shaped sealing ring is not precompressed, the movement resistance is small, the piston 2 moves bidirectionally and smoothly, and the reduction of power consumption is facilitated.

The last explanation is: the above embodiments are only for illustrating the technical solution of the present application, but are not limited thereto; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims

1. A piston valve, comprising:

a cylinder (1) with annular side walls provided with a fluid inlet (R) and at least one fluid outlet (C) at intervals along the axial direction, wherein the fluid inlet (R) is at least used for being connected with a brake master cylinder, and the fluid outlet (C) is at least used for being connected with a brake wheel cylinder and/or a pedal feel simulator;

a piston (2) movable in the axial direction within the cylinder (1);

at least one reversing mechanism (3) arranged around the circumferential direction of the piston at the gap between the cylinder (1) and the piston (2), the reversing mechanism (3) being located between the fluid inlet (R) and the fluid outlet (C) in the axial direction and being in communication with the fluid outlet (C), the reversing mechanism (3) being switchable between a unidirectional conducting state and a bidirectional conducting state when the piston (2) is moved in the axial direction, wherein:

In the unidirectional conducting state, the reversing mechanism (3) is capable of unidirectionally sealing the gap to prevent fluid from flowing from the fluid inlet (R) through the reversing mechanism (3) to the fluid outlet (C) and to enable the fluid to flow back from the fluid outlet (C) through the reversing mechanism (3) to the fluid inlet (R);

In the bi-directional conducting state, the reversing mechanism (3) is capable of flowing the fluid from the fluid inlet (R) through the reversing mechanism (3) to the fluid outlet (C) or of flowing the fluid from the fluid outlet (C) back through the reversing mechanism (3) to the fluid inlet (R).

2. The piston valve according to claim 1, wherein the reversing mechanism (3) comprises:

a ring groove (31) and a one-way seal (32), the ring groove (31) being provided on one of an inner wall of the cylinder (1) and an outer wall of the piston (2), the one-way seal (32) being provided within the ring groove (31);

an annular outer wall (33) and an annular groove passage (34) provided adjacently on the other of the inner wall of the cylinder (1) and the outer wall of the piston (2), and the fluid inlet (R) and the annular groove passage (34) being located on both sides of the annular outer wall (33) in the axial direction, the fluid outlet (C) being in communication with the annular groove passage (34), wherein:

In the unidirectional conductive state, the unidirectional seal (32) is in contact with the annular outer wall (33), the unidirectional seal (32) being capable of sealing the gap in a direction from the fluid inlet (R) to the annular channel (34) and of flowing fluid through the gap in a direction from the annular channel (34) to the fluid inlet (R) to return to the fluid inlet (R);

In the bi-directional conduction state, the one-way seal (32) corresponds to the annular channel (34), enabling the fluid to flow through the annular channel (34) in a direction from the fluid inlet (R) to the annular channel (34) to flow to the fluid outlet (C) or in a direction from the annular channel (34) to the fluid inlet (R) to flow through the annular channel (34) to flow back to the fluid inlet (R).

3. The piston valve of claim 2, wherein the one-way seal (32) comprises a lip seal with a lip facing the side of the fluid inlet (R), wherein:

When the unidirectional sealing element (32) is correspondingly contacted with the annular outer wall (33), the lip is expanded outwards when the pressure of fluid at the lip side is larger than that of fluid at the opposite side of the lip, so that the lip of the lip sealing ring is tightly attached to the annular outer wall (33) to realize the sealing of the gap along the direction from the fluid inlet (R) to the annular groove channel (34); when the fluid pressure of the lip side is smaller than that of the opposite side of the lip, the lip contracts to enable the lip of the lip-shaped sealing ring to be separated from the annular outer wall (33) to form a gap, so that the fluid flows from the opposite side of the lip to the lip side through the gap, and one-way sealing or one-way conduction is realized;

In the case of the unidirectional seal (32) corresponding to the annular groove channel (34), the fluid can flow from the lip side to the opposite side of the lip through the annular groove channel (34) when the pressure of the fluid on the lip side is greater than the pressure of the fluid on the opposite side of the lip; when the pressure of the fluid on the lip side is smaller than the pressure of the fluid on the opposite side of the lip, the fluid can flow from the opposite side of the lip to the lip side through the annular groove passage (34), thereby realizing bidirectional communication.

4. A piston valve according to claim 2 or 3, characterized in that the annular groove channel (34) comprises a plurality of groove bodies (G) arranged at intervals in the circumferential direction around the other of the inner wall of the cylinder (1) and the outer wall of the piston (2), the outer wall (W) between adjacent groove bodies (G) being capable of supporting contact with the unidirectional seal (32) when the unidirectional seal (32) corresponds to the annular groove channel (34).

5. The piston valve of claim 4 wherein:

The dimension of the groove body (G) in the axial direction is greater than or less than or equal to the dimension in the circumferential direction; and/or the number of the groups of groups,

The longitudinal section or the cross section of the groove body (G) is arc-shaped, and two ends of the arc along the bending direction are far away from the central axis of the piston (2) relative to the middle part of the arc.

6. A piston valve according to any one of claims 1-3, characterized in that the cylinder (1) is provided with two fluid outlets (C), the fluid inlet (R) being located between the two fluid outlets (C) in the axial direction, the two fluid outlets (C) being a first fluid outlet (C1) and a second fluid outlet (C2), the piston valve comprising two reversing mechanisms (3), the two reversing mechanisms (3) being a first reversing mechanism (3 a) and a second reversing mechanism (3 b); -the first reversing mechanism (3 a) is located between the fluid inlet (R) and the first fluid outlet (C1) in the axial direction and communicates with the first fluid outlet (C1), -the second reversing mechanism (3 b) is located between the fluid inlet (R) and the second fluid outlet (C2) in the axial direction and communicates with the second fluid outlet (C2); the piston (2) is movable between a first position and a second position, wherein:

In the first position, the first reversing mechanism (3 a) is in the bidirectional conduction state, and the second reversing mechanism (3 b) is in the unidirectional conduction state;

in the second position, the first reversing mechanism (3 a) is in the unidirectional conduction state, and the second reversing mechanism (3 b) is in the bidirectional conduction state.

7. A piston valve according to any one of claims 1-3, characterized in that an annular channel (T) is provided on the other of the inner wall of the cylinder (1) and the outer wall of the piston (2), the fluid inlet (R) being in communication with the annular channel (T), the annular channel (T) being structurally identical or different from the annular channel (34) of the reversing mechanism (3).

8. The piston valve of any one of claims 1-3, wherein the piston valve further comprises:

A first sealing ring (M1) located at a first end of the piston (2) and capable of sealing a circumferential gap between the cylinder (1) and the piston (2) in a direction from a second end of the piston (2) to the first end of the piston (2);

A second sealing ring (M2) located at a second end of the piston (2) and capable of sealing a circumferential gap between the cylinder (1) and the piston (2) in a direction from the first end of the piston (2) to the second end of the piston (2);

The fluid inlet (R), the fluid outlet (C) and the reversing mechanism (3) are located between the first sealing ring (M1) and the second sealing ring (M2) along the axial direction.

9. The piston valve of claim 8, wherein the first seal ring (M1) and the second seal ring (M2) are each one of an O-ring seal and a lip seal, wherein:

The O-ring is capable of bi-directionally sealing the gap in a direction from a first end of the piston (2) to a second end of the piston (2) and in a direction from the second end of the piston (2) to the first end of the piston (2);

The lip seal is open towards the side of the fluid inlet (R), the lip seal being capable of unidirectionally sealing the gap in a direction from the lip side to the opposite side of the lip.

10. The piston valve according to claim 6, further comprising a drive mechanism for driving the piston (2) to move in the axial direction, the drive mechanism being one of a manual operation mechanism, an electromagnetic drive mechanism (4), a pneumatic drive mechanism, a hydraulic drive mechanism and an electro-hydraulic drive mechanism;

And, electromagnetic drive mechanism (4) include quiet iron (41), move indisputable (42), connect still iron (41) with move elastic component (43) of indisputable (42) and set up move indisputable (42) with quiet iron (41) peripheral solenoid (44), move indisputable (42) with piston (2) are connected, wherein:

when the electromagnetic coil (44) is not electrified, the moving iron (42) and the static iron (41) are arranged at intervals, and the piston (2) is positioned at a first position;

when the electromagnetic coil (44) is electrified, the movable iron (42) and the static iron (41) are magnetized, so that the movable iron (42) drives the piston (2) to move towards the static iron (41) and compress the elastic piece (43), and the piston (2) is located at the second position.

11. The piston valve according to claim 7, further comprising a drive mechanism for driving the piston (2) to move in the axial direction, the drive mechanism being one of a manual operation mechanism, an electromagnetic drive mechanism (4), a pneumatic drive mechanism, a hydraulic drive mechanism and an electro-hydraulic drive mechanism;

12. The piston valve of any of claims 3 or 9, wherein the lip seal comprises one of a U-seal, a V-seal, and a Y-seal.

13. A vehicle, characterized by comprising:

the piston valve of any one of claims 6-12;

A brake master cylinder in communication with a fluid inlet (R) of the piston valve;

a wheel and a brake cylinder communicating with a first fluid outlet (C1) of the piston valve to provide a braking force to brake the wheel when fluid is received;

A pedal feel simulator in communication with the second fluid outlet (C2) of the piston valve to simulate a pedaling force upon receipt of the fluid; wherein:

When in a first position, the brake master cylinder is in bidirectional conduction with the brake wheel cylinder through a first reversing mechanism (3 a); the brake master cylinder is in one-way conduction with the pedal feel simulator through a second reversing mechanism (3 b);

When the brake master cylinder is at the second position, the brake master cylinder is in one-way conduction with the brake wheel cylinder through the first reversing mechanism (3 a); the brake master cylinder and the pedal feel simulator are conducted in two directions through the second reversing mechanism (3 b).