Self-checking valve and braking system

Abstract

The application relates to a self-checking valve and brake system, which comprises a valve body, a movable valve rod and a first oil cavity arranged in the valve body, a first oil channel and a second oil channel as external oil ports arranged on the valve body, an oil guide hole arranged between the first oil cavity and the second oil cavity, a ball head arranged at one end of the valve rod and movable to completely or partially block the oil guide hole, and the second oil channel, the oil guide hole, the first oil cavity and the first oil channel sequentially communicated. According to the scheme, the pressure sensor is connected outside the first oil channel, the ball head of the valve rod is used to make the oil guide hole partially blocked, the throttling effect is good when the oil guide hole is in a half-open state, pressure is added through a servo pressure building unit at this time, brake fluid is discharged under a linear hovering control state of a system self-checking valve, actual pressure output of the pressure sensor is read, and comparison is made with an initial calibration curve, so that the pressure output linearity of the pressure sensor is calibrated.

Description

Technical Field

[0001] This invention relates to braking systems, and more particularly to a self-testing valve and braking system. Background Technology

[0002] Pressure sensors often deviate from their theoretical static parameters due to errors introduced during the manufacturing process. Sensors used in braking systems must meet certain accuracy requirements in terms of sensitivity, nonlinearity, and repeatability to ensure distortion-free signal conversion. Therefore, a pressure sensor calibration system must be used to calibrate them to obtain their actual performance parameters and assess their accuracy level.

[0003] In existing braking systems, there is a lack of a structure to calibrate the linearity of the pressure sensor output pressure, making it impossible to calibrate the pressure sensor in real time, which affects the detection accuracy. Summary of the Invention

[0004] This invention addresses the problem in the prior art that pressure sensors in braking systems cannot be calibrated, by providing a self-testing valve and braking system capable of linearly calibrating pressure sensors.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A self-testing valve includes a valve body, wherein a movable valve stem and a first oil chamber are provided in the valve body, and a first oil passage and a second oil passage are provided on the valve body as an external oil port, and an oil guide hole is provided between the first oil chamber and the second oil passage. One end of the valve stem is a ball head and can be moved to completely or partially block the oil guide hole. The second oil passage, the oil guide hole, the first oil chamber and the first oil passage are connected in sequence.

[0006] The beneficial effects of this invention are as follows: The valve body is provided with a first oil passage and a second oil passage for connecting to an external oil circuit structure. When oil enters through the second oil passage and exits through the first oil passage, the pressure sensor can be connected to the outside of the first oil passage. The guide hole is partially blocked by the ball head of the valve stem, i.e., the guide hole is in a half-open state, which has a good throttling effect. At this time, the pressure is increased by the servo pressure building unit, and then the brake fluid is released by the system self-test valve in the linear hovering control state. The actual pressure output of the pressure sensor is read and compared with the initial calibration curve, thereby calibrating the linearity of the pressure output of the pressure sensor. The ball head is set to block the guide hole, which has a good sealing effect. When it is half-open, the ball head can achieve uniform oil output in the circumference, resulting in a good oil guiding effect.

[0007] Based on the above technical solution, the present invention can be further improved as follows.

[0008] Furthermore, the other end of the valve stem is provided with a movable clamping member, and the valve body is provided with a stepped hole for the valve stem to pass through. One end of an elastic member in a compressed state is abutted on the end face of the stepped hole, and the other end of the elastic member presses the valve stem against the clamping member.

[0009] The beneficial effect of adopting the above-mentioned further solution is that the valve stem and valve body are respectively abutted at both ends of the elastic element, which is used to press the valve stem and the clamping element together, so that the self-test valve is kept in the normally open state, that is, the corresponding oil guide hole is in the open state.

[0010] Furthermore, both the clamping element and the valve body are magnetically conductive, and the outer periphery of the clamping element and the valve body is surrounded by energized coil windings.

[0011] The beneficial effect of adopting the above-mentioned further solution is that both the clamping element and the valve body are magnetic. When the coil winding is energized, a magnetic force will be generated to attract each other, thereby causing the clamping element to move toward the valve body and press down the valve stem. The magnitude of the magnetic field can be controlled by controlling the magnitude of the current, thereby controlling the downward pressing distance of the valve stem, that is, controlling the opening size of the oil guide hole; the clamping element can be an armature.

[0012] Furthermore, a magnetic shielding sleeve is provided inside the coil winding. The magnetic shielding sleeve is fixed to the side wall of the valve body and forms a receiving cavity at the end of the valve body. The clamping member is movably disposed in the receiving cavity.

[0013] The beneficial effect of adopting the above-mentioned further solution is that the clamping component is located inside the magnetic shielding sleeve, which serves to isolate the magnetic field. At the same time, the receiving cavity formed by the magnetic shielding sleeve serves as a limiting cavity for the movement of the clamping component.

[0014] Furthermore, rubber shock-absorbing pads are fixed to the outside of the coil winding and the magnetic shielding sleeve, and the coil winding is connected to the coil body, with the coil body passing through the shock-absorbing pads.

[0015] The beneficial effect of adopting the above-mentioned further solution is that the shock-absorbing pad has the effect of shock absorption and protects the coil body.

[0016] Furthermore, the oil guide hole is located on the first valve seat, which is a thin-walled structure and fixed inside one end of the valve body. The oil guide hole is divided into a circular hole, a first conical hole, and a second conical hole with successively increasing diameters and coaxially connected along the axial direction. The second conical hole is set towards the valve stem.

[0017] The beneficial effect of adopting the above-mentioned further scheme is that two conical holes are set. The first conical hole with a small angle to the axial direction is used for linear pressure and flow control, and the second conical hole with a large angle to the axial direction is used for large opening and large flow control. The circular hole is used for throttling, and the size and length of the circular hole determine the throttling parameters.

[0018] Furthermore, a second valve seat is fixed to the end of the first valve seat facing away from the valve stem. The second valve seat has a third conical hole. The small end of the third conical hole is connected to the first oil chamber, and the large end of the third conical hole is connected to the second oil passage and is equipped with a valve ball to form a one-way conduction structure.

[0019] The beneficial effect of adopting the above-mentioned further scheme is that the third cone hole and the valve ball form a structure that allows forward passage and cuts off in reverse.

[0020] Furthermore, a detachable valve cover is connected to the end of the second valve seat facing away from the valve body, and a filter screen is fixed on the valve cover.

[0021] The beneficial effect of adopting the above-mentioned further solution is that setting up a filter screen can isolate pollutants and prevent them from entering the internal working chamber of the solenoid valve, thus playing a protective role.

[0022] Furthermore, an exhaust hole is provided at the end of the valve stem ball head, with a diameter of 0.4 mm and a depth of 0.03 mm.

[0023] The beneficial effect of adopting the above-mentioned further solution is that by setting a mold vent at the valve port, the roundness of the high-precision spherical surface is guaranteed.

[0024] Another technical solution of the present invention to solve the above-mentioned technical problems is as follows: a braking system, including the above-mentioned self-test valve. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the self-test valve of the present invention in a first direction;

[0026] Figure 2 This is a cross-sectional view of a partial structure of the self-test valve of the present invention in a second direction;

[0027] Figure 3 This is a structural diagram of the valve stem of the present invention;

[0028] Figure 4 This is a structural diagram of the first valve seat of the present invention;

[0029] Figure 5 This is a structural diagram of the clamping component of the present invention.

[0030] The attached diagram lists the components represented by each number as follows:

[0031] 1 Valve body; 1-1 First oil chamber; 1-2 First oil passage; 1-3 Second oil passage; 1-4 Stepped orifice;

[0032] 2. Valve stem; 2-1. Exhaust port; 2-2. First flow stabilizer groove;

[0033] 3. Clamping component; 3-1. Second flow stabilizer;

[0034] 4. Elastic components;

[0035] 5. Coil winding; 6. Magnetic shielding sleeve; 7. Shock-absorbing pad; 8. Valve ball; 9. Valve cover;

[0036] 10 First valve seat; 10-1 Oil guide hole; 10-2 Round hole; 10-3 First conical hole; 10-4 Second conical hole;

[0037] 11 Second valve seat; 11-1 Third conical hole;

[0038] 12. Circular filter screen; 13. Coil frame; 14. Coil shell; 15. Coil lower yoke; 16. Coil body; 17. Laser weld. Detailed Implementation

[0039] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0040] like Figure 1 , 2 The self-test valve has three operating states, which are determined by the opening degree of the oil guide hole 10-1:

[0041] In the first configuration, the oil guide hole 10-1 is in a semi-open or partially open state, used for linear calibration of the pressure sensor. The pressure of the clamping member 3 on the valve stem 2 and the movement distance of the valve stem 2 are controlled by controlling the current in the coil winding 5, thereby controlling the opening of the oil guide hole 10-1. At this time, oil enters through the second oil passage 1-3, passes through the oil guide hole 10-1, and then through the first flow channel. The outlet of the first flow channel is connected to the pressure sensor. Correspondingly, the first conical hole 10-3 with a small axial angle is used for linear pressure and flow control, facilitating linear calibration of the pressure sensor. The calibration process involves utilizing the good sealing and linear control performance of the self-test valve TSV, pressurizing the servo pressure-building unit, and then releasing the brake fluid through the system self-test valve in a linear hovering control state. The actual pressure output of the pressure sensor is read and compared with the initial calibration curve, thereby calibrating the linearity of the pressure sensor's pressure output. When the pressure sensor is calibrated linearly, the brake fluid flows in the opposite direction from the lower end of the second oil passage 1-3 and the master cylinder suction port, through the central guide hole 10-1 of the TSV valve seat and the valve stem 2 at a small opening for throttling, and then flows from the side end of the first oil passage 1-2 to the oil reservoir.

[0042] The second method involves keeping the oil guide hole 10-1 fully closed to check for leaks in the circuit. The pressure of the clamping member 3 on the valve stem 2 is controlled by adjusting the current in the coil winding 5, pressing the valve stem 2 against the oil guide hole 10-1, thus completely closing it. The self-test valve then isolates the liquid at both ends of the oil guide hole 10-1, preventing relative flow and allowing each end to form a closed circuit. For example, if the second valve seat 11 is connected to the master cylinder, during the onebox system's power-on self-test, the system self-test valve TSV is energized and closed, isolating the reservoir T1 port from the master cylinder's first chamber PC. At this time, the master cylinder chamber, simulator chamber, and wheel cylinder chamber form an independent closed hydraulic circuit, pressurized by the servo pressure building unit PSU, and then the pressure sensor detects whether the entire braking circuit leaks. During the system's hydraulic circuit self-test, the self-test valve TSV is energized, completely isolating the first oil passage 1-2 (side port) connected to the oil reservoir and the second oil passage 1-3 (lower port) connected to the master cylinder's oil suction port.

[0043] The third type is when the oil guide hole 10-1 is fully open. At this time, the coil winding 5 is not energized, the self-test valve is not working, and there is no pressure difference between the two ends of the valve ball 8 and it is in the open position.

[0044] Furthermore, the self-test valve can also achieve specific or customized pedal feel. During the pedal feel simulator's oil intake and return, the linear control performance of the system's self-test valve (TSV) is utilized to control the return oil speed and flow rate by adjusting the TSV opening, thus achieving a specific or customized pedal feel. When a specific pedal feel is achieved, the brake fluid flows back from the lower end of the second oil passage 1-3 and the master cylinder intake port to the side end of the first oil passage 1-2 and then to the reservoir.

[0045] Example 1

[0046] A self-testing valve includes a valve body 1, a movable valve stem 2 and a first oil chamber 1-1 inside the valve body 1, a first oil passage 1-2 and a second oil passage 1-3 as an external oil inlet on the valve body 1, an oil guide hole 10-1 between the first oil chamber 1-1 and the second oil passage 1-3, one end of the valve stem 2 is a ball head and can be moved to completely or partially block the oil guide hole 10-1, and the second oil passage 1-3, the oil guide hole 10-1, the first oil chamber 1-1 and the first oil passage 1-2 are connected in sequence.

[0047] The beneficial effects of this embodiment are as follows: The valve body 1 is provided with a first oil passage 1-2 and a second oil passage 1-3 for connecting to the external oil circuit structure. When oil enters the second oil passage 1-3 and oil exits the first oil passage 1-2, the pressure sensor can be connected to the outside of the first oil passage 1-2. The oil guide hole 10-1 is partially blocked by the ball head of the valve stem 2, that is, when the oil guide hole 10-1 is in a half-open state, the throttling effect is good. At this time, the pressure is increased by the servo pressure building unit, and then the brake fluid is released by the system self-test valve in the linear hovering control state. The actual pressure output of the pressure sensor is read and compared with the initial calibration curve, thereby calibrating the linearity of the pressure output of the pressure sensor. The ball head is set to block the oil guide hole 10-1, which has a good sealing effect. When it is half-open, the oil can be evenly discharged around the ball head, resulting in a good oil guiding effect.

[0048] Based on the above embodiment, the outer side of the first oil passage 1-2 is connected to the oil reservoir, and the outer side of the second oil passage 1-3 is connected to the master cylinder; the self-test valve is columnar, the first oil passage 1-2 is located on the side of the valve body 1, and the second oil passage 1-3 is located at the end of the valve body 1. At this time, an annular filter 12 can be set at the location of the first oil passage 1-2. The annular filter 12 surrounds the valve body 1, which can isolate large lateral contaminants and prevent large lateral contaminants from entering the internal working chamber of the solenoid valve.

[0049] Example 2

[0050] Preferably, based on embodiment 1, the other end of the valve stem 2 is provided with a movable clamping member 3, and the valve body 1 is provided with a stepped hole 1-4 for the valve stem 2 to pass through. One end of an elastic member 4 in a compressed state is abutted on the end face of the stepped hole 1-4, and the other end of the elastic member 4 presses the valve stem 2 against the clamping member 3.

[0051] The beneficial effect of adopting the preferred solution in the above embodiments is that the elastic element 4 has valve stem 2 and valve body 1 abutting at both ends respectively, which is used to press valve stem 2 and clamping element 3 together, so that the self-test valve is kept in the normally open state, that is, the corresponding oil guide hole 10-1 is in the open state.

[0052] Based on the above embodiments, the valve stem 2 has a tapered structure. The end of the valve stem 2 closest to the clamping member 3 is the large end, and the end of the valve stem 2 with a ball head is the small end. The middle part of the valve stem 2 is provided with a shoulder for abutting against the elastic member 4. Under the action of the elastic member 4, the large end of the valve stem 2 always keeps in contact with the clamping member 3. The valve stem 2 can be a high-precision injection molded part made of PEEK material. The large end of the valve stem 2 has 4 first flow stabilizing grooves 2-2 along the axial direction. The ball head of the small end of the valve stem 2 is a high-precision valve port sealing surface. The valve stem 2 made of PEEK material has a small mass and a small moment of inertia, which is beneficial for linear "hovering" stability control and noise control.

[0053] like Figure 1 and Figure 3The elastic element 4 can be a structure that is elastic and has a rebound force after compression. A spring can be preferred. The spring can be a small diameter cylindrical compression spring to provide a restoring force when the solenoid valve is opened and closed. In the non-energized state, the pre-pressure of the spring keeps the exhaust port 2-1 of the self-test valve normally open.

[0054] like Figure 5 The clamping part 3 is a cold-forged part with two second flow-stabilizing grooves 3-1 along the axial direction, and has good magnetic permeability. After the electromagnetic coil is energized, it provides thrust for the valve stem 2 to close, pushing the valve stem 2 to seal with the valve seat or to keep it in a certain position. The corresponding oil guide hole 10-1 is partially opened to output a specific pressure or flow.

[0055] Example 3

[0056] Preferably, based on embodiments 1-2, both the clamping member 3 and the valve body 1 are magnetically conductive, and the outer periphery of the clamping member 3 and the valve body 1 is surrounded by an energized coil winding 5.

[0057] The beneficial effect of adopting the preferred solution in the above embodiments is that both the clamping member 3 and the valve body 1 are magnetic. When the coil winding 5 is energized, a magnetic force will be generated to attract each other, thereby causing the clamping member 3 to move toward the valve body 1 and press down the valve stem 2. The magnitude of the magnetic field can be controlled by controlling the magnitude of the current, thereby controlling the downward pressing distance of the valve stem 2, that is, controlling the opening size of the oil guide hole 10-1; the clamping member 3 can be an armature.

[0058] In this embodiment, a coil frame 13 can be provided as a carrier for the coil winding 5, allowing the coil winding 5 to be wound on the coil frame 13, facilitating coil winding and density adjustment. The coil frame 13 can be an insulating plastic part injection molded from PA66+30GF or PBT material. The coil winding 5 can be a helical coil wound on the coil frame 13 with enameled wire at 220°C, with a wire diameter of 0.25mm, 552 turns, 12 layers, and a resistance value of 7.3±0.2Ω.

[0059] Example 4

[0060] Preferably, based on embodiments 1-3, a magnetic shielding sleeve 6 is provided inside the coil winding 5. The magnetic shielding sleeve 6 is fixed to the side wall of the valve body 1 and forms a receiving cavity at the end of the valve body 1. The clamping member 3 is movably disposed in the receiving cavity.

[0061] The beneficial effect of adopting the preferred solution in the above embodiments is that the clamping member 3 is provided inside the magnetic shielding sleeve 6, the magnetic shielding sleeve 6 plays the role of isolating the magnetic field, and at the same time, the receiving cavity formed by the magnetic shielding sleeve 6 serves as a limiting cavity for the movement of the clamping member 3.

[0062] Based on this embodiment, the magnetic shielding sleeve 6 is a precision stamped part made of stainless and non-magnetic material. After being connected to the valve body 1 by laser welding, it forms a receiving cavity, which serves as the upper cavity of the hydraulic working chamber of the self-test valve. The coil winding 5 is surrounded by a coil housing 14 and a lower coil yoke 15, which are connected. The coil housing 14 extends to the magnetic shielding sleeve 6. Specifically: 1) The yoke of the coil housing 14 is a high-permeability part made of soft magnetic material through stretching and stamping, serving as the main path for the closed loop of external magnetic lines of force generated by the coil winding 5. The upper plane and inner flange of the coil housing 14 constitute the upper coil yoke. The coil housing 14 and the magnetic shielding sleeve 6 are fitted with a small clearance. The lower part of the coil housing 14 is press-fitted with the lower coil yoke 15 to minimize magnetic leakage. 2) The lower coil yoke 15 is made of a soft magnetic material with high permeability, enabling the coil winding 5 to generate a closed loop of magnetic lines of force at the bottom of the coil. The upper end face of the lower coil yoke 15 is in contact with the lower end face of the coil frame 13, and the outer circular surface of the lower coil yoke 15 is press-fitted with the inner circular surface of the coil housing 14. The magnetic shielding sleeve 6 is connected to the valve body 1 by laser welding to form the upper chamber of the hydraulic working chamber of the self-test valve.

[0063] Example 5

[0064] Preferably, based on embodiments 1-4, a rubber shock-absorbing pad 7 is fixed outside the coil winding 5 and the magnetic shielding sleeve 6, and the coil winding 5 is connected to the coil body 16, which passes through the shock-absorbing pad 7.

[0065] The beneficial effect of adopting the preferred solution in the above embodiments is that the shock-absorbing pad 7 plays a role in shock absorption and protects the coil body 16.

[0066] Based on this embodiment, the damping pad 7 is made of vibration-damping rubber vulcanized from EPDM material. The damping pad 7 can provide preload for the coil when mounted on the solenoid valve and attenuate the vibration of the coil and solenoid valve during engagement and disengagement, so as to protect the coil body 16PI N and the crimped conductive structure of the ECU PCB board and improve durability.

[0067] The coil body 16 can be a solid press-fit structure, which is the lead connecting the coil winding 5 and the ECU PCB board. It is connected to the ECU PCB board through a press-fit structure. The ECU PCB board provides voltage or current control signals to the coil winding 5 through the coil body 16.

[0068] Example 6

[0069] like Figure 1 and Figure 4Preferably, based on embodiments 1-5, the oil guide hole 10-1 is provided on the first valve seat 10. The first valve seat 10 has a thin-walled structure and is fixed inside one end of the valve body 1. The oil guide hole 10-1 is divided along the axial direction into a circular hole 10-2, a first conical hole 10-3, and a second conical hole 10-4, which are successively enlarged in diameter and coaxially connected. The second conical hole 10-4 is set towards the valve stem 2.

[0070] The beneficial effect of adopting the preferred scheme in the above embodiments is that two conical holes are provided. The first conical hole 10-3 with a small angle to the axial direction is used for linear pressure and flow control, and the second conical hole 10-4 with a large angle to the axial direction is used for large opening and large flow control. The circular hole 10-2 is used for throttling. The size and length of the circular hole 10-2 determine the throttling parameters.

[0071] Based on this embodiment, the first valve seat 10 can be a high-precision thin-walled precision stretching part, and the two conical surfaces provided at the valve port are two inner conical surfaces that are connected to each other, and the inner conical surfaces are ground.

[0072] Example 7

[0073] Preferably, based on embodiments 1-6, a second valve seat 11 is fixed to one end of the first valve seat 10 facing away from the valve stem 2. The second valve seat 11 has a third conical hole 11-1. The two ends of the third conical hole 11-1 are respectively connected to the first oil chamber 1-1 and the second oil passage 1-3. The small end of the third conical hole 11-1 is connected to the first oil chamber 1-1, and the large end of the third conical hole 11-1 is connected to the second oil passage 1-3 and is provided with a valve ball 8 to form a one-way conduction structure.

[0074] The beneficial effect of adopting the preferred solution in the above embodiments is that the third conical hole 11-1 and the valve ball 8 form a structure that allows forward conduction and reverse cut-off.

[0075] Based on this embodiment, the second valve seat 11 can be an integral plastic part formed by bonding an annular filter screen 12 to a one-way valve plastic seat body. The upper positioning surface of the second valve seat 11 is fitted with the lower end of the valve body 1; the upper sealing post of the second valve seat 11 is interference-fitted with the inner circular surface of the first valve seat 10. The diameter of the valve ball 8 can be 1.7mm. The valve ball 8 is made of PEEK material. The PEEK material valve ball 8 has small mass and small moment of inertia, and has the advantages of good sealing performance and fast opening and closing response speed. When there is a pressure difference between the two ends of the valve ball 8, it will push the valve ball 8 to move, so that the valve ball 8 is fitted or separated from the third conical hole 11-1, thereby corresponding to the open and closed states of the valve ball 8 and the third conical hole 11-1. In addition, the diameter of the valve ball 8 can be 1.2mm, and the through diameter of the third conical hole 11-1 can be 0.67mm.

[0076] Example 8

[0077] Preferably, based on embodiments 1-7, the second valve seat 11 is connected to a detachable valve cover 9 at the end facing away from the valve body 1, and a filter screen is fixed on the valve cover 9.

[0078] The beneficial effect of adopting the preferred solution in the above embodiments is that the filter screen can isolate pollutants and prevent them from entering the internal working chamber of the solenoid valve, thus playing a protective role.

[0079] Based on this embodiment, the valve cover 9 can serve as the lower limit of the one-way valve ball 8.

[0080] Based on the above embodiments, the valve cover 9 can be an integrated plastic part combined with the lower filter screen, and the inner circumferential surface of the valve cover 9 and the outer circumferential surface of the lower end of the valve seat are connected by interference fit.

[0081] Example 9

[0082] Preferably, based on embodiments 1-8, the end of the ball head of valve stem 2 is provided with an exhaust hole 2-1, the diameter of exhaust hole 2-1 is 0.4mm and the depth is 0.03mm.

[0083] The beneficial effect of adopting the preferred solution in the above embodiments is that the mold exhaust hole 2-1 is set at the valve port to ensure the roundness of the high-precision spherical surface.

[0084] Example 10

[0085] Preferably, based on embodiments 1-8, another technical solution of the present invention to solve the above-mentioned technical problems is as follows: a braking system, including the above-mentioned self-test valve.

[0086] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0087] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0088] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0089] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0091] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A self-testing valve, characterized in that, Includes a valve body (1), which has a movable valve stem (2) and a first oil chamber (1-1) inside. The valve body (1) has a first oil passage (1-2) and a second oil passage (1-3) as an external oil inlet. An oil guide hole (10-1) is provided between the first oil chamber (1-1) and the second oil passage (1-3). One end of the valve stem (2) is a ball head and can be moved to completely or partially block the oil guide hole (10-1). The second oil passage (1-3), the oil guide hole (10-1), the first oil chamber (1-1), and the first oil passage (1-2) are connected in sequence. The other end of the valve stem (2) is provided with a movable clamping member (3). 1) A stepped hole (1-4) is provided inside for the valve stem (2) to pass through. One end of an elastic element (4) in a compressed state is abutted on the end face of the stepped hole (1-4). The other end of the elastic element (4) presses the valve stem (2) against the clamping element (3). The oil guide hole (10-1) is provided on the first valve seat (10). The first valve seat (10) is a thin-walled structure and is fixed in one end of the valve body (1). The oil guide hole (10-1) is divided into a circular hole (10-2), a first conical hole (10-3), and a second conical hole (10-4) with increasing diameters and connected coaxially in sequence. The second conical hole (10-4) is set towards the valve stem (2).

2. The self-test valve according to claim 1, characterized in that, Both the clamping member (3) and the valve body (1) are magnetically conductive, and the outer periphery of the clamping member (3) and the valve body (1) is surrounded by an energized coil winding (5).

3. A self-testing valve according to claim 2, characterized in that, The inner side of the coil winding (5) is provided with a magnetic shielding sleeve (6), which is fixed to the side wall of the valve body (1) and forms a receiving cavity at the end of the valve body (1). The clamping member (3) is movably disposed in the receiving cavity.

4. A self-testing valve according to claim 3, characterized in that, Rubber shock-absorbing pads (7) are fixed to the outside of the coil winding (5) and the magnetic shielding sleeve (6). The coil winding (5) is connected to the coil body (16), and the coil body (16) passes through the shock-absorbing pads (7).

5. A self-testing valve according to claim 1, characterized in that, The first valve seat (10) has a second valve seat (11) fixed at one end facing away from the valve stem (2). The second valve seat (11) has a third conical hole (11-1). The small end of the third conical hole (11-1) is connected to the first oil chamber (1-1), and the large end of the third conical hole (11-1) is connected to the second oil passage (1-3) and has a valve ball (8) to form a one-way conduction structure.

6. A self-testing valve according to claim 5, characterized in that, The second valve seat (11) is connected to a detachable valve cover (9) at the end facing away from the valve body (1), and a filter screen is fixed on the valve cover (9).

7. A self-testing valve according to claim 1, characterized in that, The valve stem (2) has an exhaust hole (2-1) at the end of the ball head. The exhaust hole (2-1) has a diameter of 0.4 mm and a depth of 0.03 mm.

8. A braking system, characterized in that, Includes the self-test valve described in any one of claims 1-7.

Images