Valve device for vehicle electronic brake system and vehicle electronic brake system

Abstract

A valve device (200) for a vehicle electronic brake system (100) and the vehicle electronic brake system (100). The valve device (200) comprises: a housing (40); an electromagnet (42); a first piston (44); a first spacer (56), wherein a pilot chamber (60) in the housing (40) is in fluid communication with a brake pedal side of a brake circuit of the vehicle electronic brake system (100); a second spacer (62), wherein a control chamber (66) is in fluid communication with a brake actuator side of the brake circuit, and a high-pressure chamber (68) is in fluid communication with a high-pressure air source side of the brake circuit; and a relay valve (70) which comprises a second piston (76), wherein in an unactuated valve position of the valve device (200), the electromagnet (42) is de-energized, and the first piston (44) abuts against the second piston (76) and the second piston (76) abuts against the second spacer (62), so as to isolate the high-pressure chamber (68) from the control chamber (66); and in a first operating valve position of the valve device (200), the electromagnet (42) is energized and pushes the first piston (44) through the second spacer (62) to push the second piston (76) towards a second axial end of the housing (40), so as to make the high-pressure chamber (68) in fluid communication with the control chamber (66), such that high-pressure air from the high-pressure air source side enters the brake actuator side through the high-pressure chamber (68) and the control chamber (66) to generate braking pressure.

Description

Valve devices for vehicle electronic braking systems and vehicle electronic braking systems Technical Field

[0001] This application relates to valve devices for vehicle electronic braking systems and vehicle electronic braking systems. Background Technology

[0002] A vehicle's Electronic Brake System (EBS) typically includes an electronic control unit and three braking circuits to facilitate a comfortable, electronically controlled braking process. Each braking circuit utilizes a valve device to modulate compressed air from a high-pressure air source to achieve the desired braking pressure. Current valve devices are complex in structure and contain numerous solenoid valves, each with a unique function, on the associated piping. Therefore, they are prone to failure if one solenoid valve malfunctions, and their response time during braking is relatively slow. Summary of the Invention

[0003] One object of this application is to provide an improved valve device and electronic braking system for vehicles to address some problems existing in the prior art.

[0004] According to a first aspect of this application, a valve device for a vehicle electronic braking system is provided, comprising: a housing; an electromagnet extending from a first shaft end of the housing into the housing; a first piston slidably fitted onto the electromagnet; a first spacer disposed on the outer periphery of the first piston; a pilot chamber in the housing between the first spacer and the first shaft end and in fluid communication with the brake pedal side of the brake circuit of the vehicle electronic braking system; a second spacer disposed in the housing; a control chamber between the first spacer and the second spacer, in fluid communication with the pilot chamber via a perforation in the first spacer, and in fluid communication with the brake side of the brake circuit; and a high-pressure chamber between the second spacer and the housing. The high-pressure gas source side of the brake circuit is fluidly connected between the second shaft ends of the housing and the second shaft end of the housing; a relay valve extends from the second shaft end of the housing into the housing, the relay valve including a second piston, in the valve device in the unactivated valve position, the electromagnet is de-energized, the first piston abuts against the second piston, and the second piston abuts against the second spacer to isolate the high-pressure chamber from the control chamber, and in the first operating valve position of the valve device, the electromagnet is energized and pushes the first piston through the second spacer toward the second shaft end of the housing to push the second piston to fluidly connect the high-pressure chamber to the control chamber, and the high-pressure gas from the high-pressure gas source side enters the brake side through the high-pressure chamber and the control chamber to generate braking pressure.

[0005] According to a second aspect of this application, a vehicle electronic braking system is provided, comprising: an electronic control device; a single-channel electro-pneumatic modulator, a dual-channel electro-pneumatic modulator, and a trailer control valve device, wherein at least one of the single-channel electro-pneumatic modulator, the dual-channel electro-pneumatic modulator, and the trailer control valve device includes the aforementioned valve device, wherein the electronic control device is configured to control the valve device.

[0006] The valve device provided in this application can complete all operations of the valve device during braking solely by an electromagnet mounted in the housing for directly actuating the first piston. This reduces the risk of encountering a failure of one of the numerous solenoid valves, simplifies the valve device structure, and improves the response speed of the valve device during braking. Furthermore, the response speed of the valve device during braking is further improved by utilizing optional solenoid valves. The vehicle electronic braking system provided in this application will also possess the aforementioned advantages by applying such a valve device.

[0007] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0008] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0009] Figure 1 is a schematic block diagram of a vehicle electronic braking system according to an embodiment of this application.

[0010] Figure 2 is a schematic cross-sectional view of a valve device for the vehicle electronic braking system of Figure 1 according to an embodiment of this application.

[0011] Figure 3 is another schematic cross-sectional view of the valve device in Figure 2.

[0012] Figure 4 is another schematic cross-sectional view of the valve device in Figure 2. Detailed Implementation

[0013] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0014] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0015] Techniques, methods, apparatuses, and systems known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, apparatuses, and systems should be considered part of the specification.

[0016] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0017] Figure 1 illustrates an exemplary vehicle electronic braking system 100 of this application, which is particularly applicable to trucks including tractors and trailers, and may include an electronic control unit 10 and three braking circuits, namely, a first braking circuit, a second braking circuit, and a third braking circuit. The electronic control unit 10, as the central control center of the vehicle electronic braking system 100, can communicate with and / or control at least some of the electronic devices associated with the three braking circuits in a wired or wireless manner (as shown by the dashed lines in Figure 1) based on the specific application. Both the electronic control unit 10 and these electronic devices can be powered by a vehicle battery (not shown).

[0018] The first braking circuit originates from a first air tank 12. The first air tank 12 is connected in parallel via a conduit to the first air inlet 14a1 of the brake pedal 14 and the first air inlet 16a1 of the single-channel electronic pneumatic modulator (SEPM). It is then connected via a conduit from the first air outlet 14b1 of the brake pedal 14 to the second air inlet 16a2 of the SEPM. From the exemplary air outlet 16b of the SEPM, it is connected via a conduit to the air inlet 18a of the exemplary ABS valve 18 of the anti-lock braking system (ABS). Finally, it is connected via a conduit from the air outlet 18b of the exemplary ABS valve 18 to the exemplary front wheel brake 20 for braking the front wheels during driving. It is understood that the number of exemplary air outlets 16b of the SEPM, the exemplary ABS valve 18, and the exemplary front wheel brake 20 will be determined based on the number of front wheels.

[0019] The second braking circuit originates from the second air tank 22, which is connected in parallel via a conduit to the second air inlet 14a2 of the brake pedal 14 and the first air inlet 24a1 of the dual-channel EPM 24. The air tank 22 is then connected in parallel via a conduit from the second air outlet 14b2 of the brake pedal 14 to the second air inlet 24a2 of the dual-channel EPM 24 and the first air inlet of the trailer control valve device 26. Finally, the circuit is connected via a conduit from the exemplary air outlet 24b of the dual-channel EPM 24 to the exemplary rear wheel brake 28 for braking the rear wheels during driving. It is understood that the number of exemplary air outlets 24b of the dual-channel EPM 24 and the number of exemplary rear wheel brakes 28 will be determined based on the number of rear wheels.

[0020] The third braking circuit starts with the third air tank 30, which is connected in parallel via a pipeline to the air inlet 32a of the parking brake control device 32 (e.g., handbrake) and the second air inlet 26a2 of the trailer control valve device 26. It is then connected via a pipeline from the first air outlet 32b1 of the parking brake control device 32 to the third air inlet 26a3 of the trailer control valve device 26. Simultaneously, it is connected via a pipeline from the second air outlet 32b2 of the parking brake control device 32 to the first air inlet 34a of a separate control valve 34. An exemplary air outlet 34b of the separate control valve 34 is connected to the parking brake 36 of the rear wheel for braking the rear wheel when parked. In the case where the vehicle electronic braking system 100 is used for a truck, the exemplary air outlet 26b of the trailer control valve device 26 is connected to the pneumatic system of the trailer and ultimately to the trailer wheel brake 38 for braking the exemplary trailer wheel during driving in a manner similar to the second braking circuit. It is understood that the number of exemplary air outlets 26b of the trailer control valve device 26 and the number of exemplary trailer wheel brakes 38 will be determined based on the number of trailer wheels.

[0021] The compressed air in the first to third air tanks 12, 22, and 30 can come from at least one air compressor (not shown).

[0022] In the vehicle electronic braking system 100, when the brake pedal 14 is depressed, the electronic brake sensor associated with the brake pedal 14 detects the degree to which the brake pedal 14 is depressed and generates a brake request signal related to the degree to which the brake pedal 14 is depressed. The electronic control unit 10 determines the desired braking pressure based on the brake request signal from the electronic brake sensor, and controls the relevant electronic devices (e.g., electromagnets, solenoid valves) in any one of the single-channel electro-pneumatic modulator 16, the dual-channel electro-pneumatic modulator 24, and the trailer control valve device 26 based on the desired braking pressure, so that the pressure of compressed air from any one of the first to third air tanks 12, 22, 30 is modulated in each of the single-channel electro-pneumatic modulator 16, the dual-channel electro-pneumatic modulator 24, and the trailer control valve device 26. Simultaneously, each of the single-channel electro-pneumatic modulator 16, the dual-channel electro-pneumatic modulator 24, and the trailer control valve device 26 is equipped with a pressure sensor 84 to detect in real time whether the compressed air therein is modulated to have the desired braking pressure.

[0023] Therefore, for the vehicle electronic braking system 100, compressed air is mainly modulated to the desired braking pressure via electronic control. In the event of failure of the relevant electronic components, the pressure of compressed air can be purely pneumatically modulated in any of the single-channel electronic pneumatic modulator 16, the dual-channel electronic pneumatic modulator 24, and the trailer control valve device 26 via redundant pipelines designed in the first to third braking circuits.

[0024] Any of the single-channel electro-pneumatic modulator 16, the dual-channel electro-pneumatic modulator 24, and the trailer control valve device 26 mentioned herein can include the exemplary valve device 200 of this application, and in particular, the exemplary valve device 200 of this application can be part of the trailer control valve device 26.

[0025] Taking Figure 2 as an example, the exemplary valve device 200 includes: a housing 40, which may include a separate housing end cap 41 and a base 43, which are sealed together; an electromagnet 42 extending axially from a first axial end of the housing 40, i.e., the housing end cap 41, into the housing 40; and a first piston 44 slidably mounted on the electromagnet 42.

[0026] For example, the electromagnet 42 includes a first sleeve 46 extending axially from the first shaft end of the housing 40, i.e. the housing end cap 41, into the housing 40. In some embodiments, including this embodiment, the first sleeve 46 is integrally formed with the housing end cap 41. In other embodiments, it can be set separately, as long as the first sleeve 46 is fixed relative to the housing 40. A first piston 44 is slidably fitted onto a first sleeve 46. For example, the first piston 44 includes an axially extending cylindrical layer 44a that slides with the radial outer peripheral surface of the first sleeve 46, and an abutting connector 44b disposed at a first axial end of the cylindrical layer 44a. The axial length of the cylindrical layer 44a is equal to or less than the axial length of the radial outer peripheral surface of the first sleeve 46. A groove 48 extends axially away from the first axial end of the first sleeve 46 and away from the second axial end of the first sleeve 46. A first spring 50 is received in the groove 48. An armature 52 is disposed in the first sleeve 46, and the first axial end of the armature 52 is at least partially received in the groove 48 so as to be pushed by the first spring 50, that is, the first spring 50 is compressed, and the second axial end of the armature 52 is pushed away from the first spring 50 due to the thrust from the first spring 50. The second shaft end of the sleeve 46 extends partially to abut against the abutment connector 44b of the first piston 44 and is sufficient to push the first piston 44 relative to the first sleeve 46; and a hollow magnetizing assembly is located between the radial inner circumferential surface of the first sleeve 46 and the radial outer circumferential surface of the armature 52. The hollow magnetizing assembly may include an electromagnetic coil 48a disposed around the inner circumferential surface of the first sleeve 46 and a hollow static magnetic core 48b disposed around the inner circumferential surface of the electromagnetic coil 48a. When the electromagnet 42 is energized, the electromagnetic coil 48a generates a magnetic force and the hollow static magnetic core 48b modulates and locally enhances the magnetic force generated by the electromagnetic coil 48a. The magnetic force pushes the second shaft end of the armature 52 to extend further from the second shaft end of the first sleeve 46 to further push the first piston 44 relative to the first sleeve 46.

[0027] For example, a protruding opening is formed at the second shaft end of the first sleeve 46 by the first sleeve 46 and / or the hollow magnetizing assembly. The diameter of the second shaft end of the armature 52 is slightly smaller than the diameter of the rest of the armature 52, and the diameter of the protruding opening is between the diameter of the second shaft end of the armature 52 and the diameter of the rest of the armature 52, so that only the second shaft end of the armature 52 can protrude from the protruding opening, while the rest of the armature 52 is blocked by the first sleeve 46 and / or the magnetizing assembly forming the protruding opening, thus limiting the protrusion range of the armature 52. Therefore, there will be a certain difference between the inner diameter of the hollow static magnetic core 48b and, in particular, the diameter of the second shaft end of the armature 52. When the second shaft end of the armature 52 does not fully protrude from the second shaft end of the first sleeve 46, such a difference will cause an undesirable gap 54 filled with air medium to be generated in the hollow magnetizing assembly. Therefore, the difference should be minimized.

[0028] A first spacer 56 is provided on the radially outer peripheral surface of the first piston 44, for example near the second axial end of the cylindrical layer 44a. In some embodiments, including this one, the first spacer 56 is integrally formed with the first piston 44; in other embodiments, it can be provided separately, as long as it can isolate the pilot cavity 60 and the control cavity 66 into relatively independent chambers. Both axial end faces of the first spacer 56 can be bent, tilted, or flexed at least partially toward the second axial end of the housing 40 to form an umbrella-like surface that substantially covers the radial cross-section of the inner wall of the housing 40. Additionally, an elastic sealing ring 58 can be provided on the radially outer peripheral surface of the first spacer 56. The elastic sealing ring 58 is deformed by compression due to contact with the inner wall of the housing 40 and can slide relative to the inner wall. Furthermore, a stop 59 can be provided in the housing 40 relative to one of the two axial end faces of the first spacer 56 to limit the sliding range of the first spacer 56 and therefore the first piston 44.

[0029] A pilot cavity 60 in the housing 40 is defined by the first spacer 56 and the inner wall of the housing 40 at its first shaft end, and the pilot cavity 60 is configured to be in fluid communication with the brake pedal side of any of the first to third brake circuits via the housing 40, for example, the first port 40a of the base 43. That is, the first port 40a of the housing 40 can be used as the second air inlet 16a2 of the single-channel electro-pneumatic modulator 16, the second air inlet 24a2 of the dual-channel electro-pneumatic modulator 24, or the third air inlet 26a3 of the trailer control valve device 26.

[0030] The valve device 200 also includes a second spacer 62 disposed in the housing 40. The second spacer 62 is located in the middle of the housing 40, is annular, and has an inner ring portion 62a forming an opening. The inner ring portion 62a is deflected toward the second axial end of the housing 40 to form a contact end face with a smaller area. Additionally, a fixed-sealing integrated ring 64 may be provided between the radially outer peripheral surface of the second spacer 62 and the inner wall of the housing 40. It is understood that the second spacer 62 is formed separately in some embodiments, including this embodiment; however, the second spacer 62 may also be integrally formed with the housing 40, thus eliminating the need for the fixed-sealing integrated ring 64.

[0031] The control cavity 66 in the housing 40 is defined by the first spacer 56, the second spacer 62, and the inner wall of the housing 40 between the first spacer 56 and the second spacer 62. The control cavity 66 is fluidly connected to the pilot cavity 60 via an axial pore specially provided in the first spacer 56. It can be understood that the volume of the pore is significantly smaller than the volume of the pilot cavity 60 and the volume of the control cavity 66. That is, if the air pressure in the control cavity 66 is significantly greater than the air pressure in the pilot cavity 60, it will take a period of time to balance the air pressure in the control cavity 66 and the air pressure in the pilot cavity 60 via the axial pore. Furthermore, the control chamber 66 is in fluid communication with the front wheel brake side of the first braking circuit, the rear wheel brake side of the second braking circuit, or the trailer wheel brake side of the third braking circuit via the second port 40b of the housing 40, such as the base 43. That is, the second port 40b of the housing 40 can be used as an exemplary air outlet 16b of the single-channel electro-pneumatic modulator 16, an exemplary air outlet 24b of the dual-channel electro-pneumatic modulator 24, or an exemplary air outlet 26b of the trailer control valve device 26.

[0032] The high-pressure chamber 68 in the housing 40 is defined by the second spacer 62 and the inner wall of the housing 40 at its second shaft end, and the high-pressure chamber 68 is in fluid communication with a high-pressure air source via the housing 40, for example, the third port 40c of the base 43, i.e., any one of the first to third air tanks 12, 22, 30. That is, the third port 40c of the housing 40 can be used as the first air inlet 16a1 of the single-channel electro-pneumatic modulator 16, the first air inlet 24a1 of the dual-channel electro-pneumatic modulator 24, or the second air inlet 26a2 of the trailer control valve device 26.

[0033] The valve device 200 also includes a relay valve 70 that extends axially from the second shaft end of the housing 40 into the housing 40, is located in the high-pressure chamber 68, and is opposite to the electromagnet 42.

[0034] For example, the relay valve 70 includes: a second sleeve 72 extending axially from a second shaft end of the housing 40 into the housing 40, the second sleeve 72 including a radially outer cylinder layer 72a and a radially inner cylinder layer 72b defining an annular groove; a second spring 74 received in the annular groove, the second spring 74 being configured as, but not limited to, a helical spring; a second piston 76 including a radially outer cylinder layer 76a, a radially inner cylinder layer 76b, and an abutting connector 76c connecting the radially outer cylinder layer 76a and the radially inner cylinder layer 76b, the second piston 76 being slidably fitted onto the second sleeve 72 to be pushed by the second spring 74, that is, the second spring 74 is compressed, and the second piston 76 tends to move toward the second spacer 62 due to the thrust from the second spring 74 until the abutting connector 76c of the second piston 76 abuts against the contact end face of the second spacer 62. For example, a stop-seal integrated ring 78 can be provided between the radial outer cylinder layer 76a of the second piston 76 and the radial outer cylinder layer 72a of the second sleeve 72 to enclose the second spring 74 in the annular groove and limit the sliding range of the second piston 76.

[0035] The radial inner cylinder layer 72b of the second sleeve 72 and the radial inner cylinder layer 72b of the second piston 76 further define the central channel 80 together, and the second shaft end of the housing 40, i.e., the base 43, also includes a fourth port 40d, which fluidly connects the central channel 80 of the second sleeve 72 to the external environment. However, even when the electromagnet 42 is de-energized, the first piston 44 is pushed by the armature 52 pushed by the first spring 50 and tends to move toward the second piston 76. The abutting connector 44b of the first piston 44 abuts against the abutting connector 76c of the second piston 76 to isolate the control cavity 66 from the central channel 80 of the second sleeve 72 and thus the external environment. At this time, the abutting connector 44b of the first piston 44 is axially separated from the second shaft end of the first sleeve 46 by a certain distance, that is, the second shaft end of the armature 52 extends partially from the second shaft end of the first sleeve 46. Specifically, the abutment connector 44b of the first piston 44 may include an abutment protrusion 44b1 extending axially away from the cylindrical layer 44a. The abutment protrusion 44b1 abuts against the abutment connector 76c of the second piston 76 to facilitate isolation. In some embodiments, including this embodiment, the abutment protrusion 44b1 is integrally formed with the abutment connector 44b; in other embodiments, it may be provided separately, as long as the abutment protrusion 44b1 can abut against the abutment connector 76c of the second piston 76 to facilitate isolation.

[0036] Optionally, the housing 40 also includes an air passage that fluidly connects the pilot chamber 60 to the external environment. This air passage can be formed by the housing 40, for example, by the fifth port 40e of the housing end cap 41 (as shown in Figure 2), or it can be formed by an air line connected in parallel with the brake pedal side of any of the first to third braking circuits. Correspondingly, the valve device 200 also includes a solenoid valve 82, which is configured to open the air passage when energized and close the air passage when de-energized; that is, the solenoid valve 82 is a normally closed solenoid valve.

[0037] In the vehicle electronic braking system 100, the electronic control unit 10 determines the desired braking pressure based on the braking request signal from the electronic braking sensor, and controls the electromagnet 42 and optional solenoid valve 82 based on the desired braking pressure so that the compressed air from the first to third air tanks 12, 22, 30 is modulated to the desired braking pressure in the valve device 200.

[0038] Here, the valve device 200 includes a first working valve position and a second working valve position to correspond to different working states of the valve device 200. The valve device 200 also includes an inactive valve position to correspond to the stopped state of the valve device 200. In the first working valve position of the valve device 200, the electronic control device 10 controls the electromagnet 42 to be energized to push the first piston 44. The first piston 44 then passes through the second spacer 62 to push the second piston 76 toward the second shaft end of the housing 40. The abutment connector 76c of the second piston 76 will disengage from the contact end face of the second spacer 62 to form a gap 77 that fluidly connects the control chamber 66 to the high-pressure chamber 68, as shown in FIG3. At this time, high-pressure gas from the high-pressure gas source enters the front wheel brake side of the first braking circuit, the rear wheel brake side of the second braking circuit, or the trailer wheel brake side of the third braking circuit through the high-pressure chamber 68 and the control chamber 66 to generate braking pressure.

[0039] As explained above, a pressure sensor 84 will be provided in the control chamber 66 of the valve device 200, for example on the first spacer 56, to detect the pressure of the compressed air in the control chamber 66 in real time during the modulation of the desired braking pressure by the valve device 200, and transmit the pressure signal related to the detected pressure to the electronic control device 10. The electronic control device 10 then combines the difference between the desired braking pressure and the detected pressure to control the electromagnet 42 to adjust the size of the gap 77, wherein the greater the current transmitted to the electromagnet 42, the larger the gap 77 and the greater the braking pressure generated. Alternatively or supplementarily, the electronic control device 10 may also control the pulse frequency of the current transmitted to the electromagnet 42 to adjust the frequency of occurrence of the gap 77, wherein the greater the pulse frequency of the current, the greater the frequency of occurrence of the gap 77 and the greater the braking pressure generated. For example, if the detected pressure is greater than the desired braking pressure, the electronic control device 10 will control the current transmitted to the electromagnet 42 to decrease and / or the pulse frequency of the current to decrease the gap 77 or the frequency of occurrence of the gap 77. Optionally, to improve the response speed of the valve device 200, the electronic control device 10 can control the solenoid valve 82 to be energized synchronously based on the decrease in the current transmitted to the electromagnet 42, thereby opening the air passage. This would further increase the pressure difference between the control chamber 66 and the pilot chamber 60, further causing the first piston 44 to retract, thus reducing the gap 77. Alternatively, the pulse frequency of the current transmitted to the solenoid valve 82 can be designed to be opposite to the pulse frequency of the current transmitted to the electromagnet 42. Conversely, if the detected pressure is less than the desired braking pressure, the electronic control device 10 will control the current transmitted to the electromagnet 42 to increase and / or increase the pulse frequency of the current, thereby increasing the gap 77 or the frequency of its occurrence.

[0040] In addition, as mentioned above, when the electromagnet 42 malfunctions, the first piston 44 and the first spacer 56 can still be pneumatically driven by the pressure of compressed air received from the brake pedal side of any of the first to third brake circuits from the first port 40a of the housing 40.

[0041] When the brake pedal 14 is released, the electronic control unit 10 will stop receiving brake request signals, and the control valve device 200 will move from the first working valve position to the second working valve position. In the second working valve position, the electromagnet 42 is completely de-energized, the magnetic force disappears relatively quickly, and the second piston 76 will move towards the second spacer 62 due to the thrust of the second spring 74 and push back the first piston 44 until the contact end face of the second piston 76 abutting the connecting member 76c returns to abutting the second spacer 62, so as to isolate the high-pressure chamber 68 from the control chamber 66. However, at this time, the pressure of the residual compressed air remaining in the control chamber 66, as well as the pressure of the residual compressed air from the front wheel brake side of the first brake circuit, the rear wheel brake side of the second brake circuit, or the trailer wheel brake side of the third brake circuit, is still significantly greater than the pressure of the pilot chamber 60 and the pressure of the residual compressed air from the brake pedal side of any of the first to third brake circuits (when the brake pedal 14 is released). When released, most of the compressed air on the brake pedal side has been discharged to the external environment by the angle valve. Due to the pressure difference between the control chamber 66 and the pilot chamber 60, the first piston 44 and the first spacer 56 will continue to retract after the contact end face of the second spacer 62 is restored to the contact end face of the second piston 76's abutment connector 76c, resisting the thrust of the armature 52 pushed by the first spring 50. As a result, the abutment connector 44b of the first piston 44 will disengage from the abutment connector 76c of the second piston 76, so that the control chamber 66 is fluidly connected to the central channel 80 of the second sleeve 72 and thus to the external environment, which is conducive to the rapid discharge of the remaining compressed air in the control chamber 66 to the external environment, as shown in Figure 4. At this time, the abutment connector 44b of the first piston 44 can abut against the second shaft end of the first sleeve 46, that is, the second shaft end of the armature 52 is completely pushed back into the first sleeve 46 from the second shaft end of the first sleeve 46.

[0042] Optionally, in the second working valve position, in order to improve the response speed of the valve device 200, the electronic control device 10 can further control the solenoid valve 82 to be energized to open the air passage, thereby further facilitating the discharge of the residual compressed air in the pilot chamber 60 to the external environment.

[0043] As the pressure in the control chamber 66 gradually equals the ambient air pressure, the first piston 44, pushed by the armature 52 abutted by the first spring 50, extends back toward the second piston 76 until the abutment connector 44b of the first piston 44 returns to abutment connector 76c of the second piston 76, thus re-isolating the control chamber 66 from the central channel 80 of the second sleeve 72 and thus the external environment. The electronic control device 10 can de-energize the solenoid valve 82 to close the air passage when the pressure signal from the pressure sensor 84 indicates that the detected pressure in the control chamber is substantially equal to the ambient air pressure. At this time, the valve device 200 moves from the second operating valve position to / re-enters the inactive valve position. In the inactive valve position, the first piston 44 abuts against the second piston 76, and the second piston 76 abuts against the second spacer 62, isolating the high-pressure chamber 68 from the control chamber 66, as shown in Figure 2.

[0044] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A valve device (200) for a vehicle electronic braking system (100), comprising: Shell (40); An electromagnet (42) extends from the first shaft end of the housing (40) into the housing (40); The first piston (44) is slidably fitted onto the electromagnet (42); The first spacer (56) is disposed on the outer periphery of the first piston (44), and the pilot cavity (60) in the housing (40) is between the first spacer (56) and the first shaft end and is in fluid communication with the brake pedal side of the brake circuit of the vehicle electronic braking system (100). The second spacer (62) is disposed in the housing (40), the control chamber (66) is between the first spacer (56) and the second spacer (62), fluidly connected to the pilot chamber (60) through the pores of the first spacer (56), and fluidly connected to the brake side of the braking circuit, while the high pressure chamber (68) is between the second spacer (62) and the second shaft end of the housing (40) and fluidly connected to the high pressure air source side of the braking circuit; A relay valve (70) extending from the second shaft end of the housing (40) into the housing (40), the relay valve (70) including a second piston (76), In the inactive valve position of the valve assembly (200), the electromagnet (42) is de-energized, the first piston (44) abuts against the second piston (76), and the second piston (76) abuts against the second spacer (62) to isolate the high-pressure chamber (68) from the control chamber (66), and In the first working valve position of the valve device (200), the electromagnet (42) is energized and pushes the first piston (44) through the second spacer (62) toward the second shaft end of the housing (40) to push the second piston (76) so as to fluidly connect the high pressure chamber (68) to the control chamber (66). High pressure gas from the high pressure gas source side enters the brake side through the high pressure chamber (68) and the control chamber (66) to generate braking pressure.

2. The valve device (200) according to claim 1, wherein, The relay valve (70) also includes a central channel (80) that fluidly connects the control chamber (66) to the external environment. In the unactivated valve position and the first working valve position of the valve device (200), the first piston (44) abuts against the second piston (76) so that the control chamber (66) is isolated from the central channel (80). In the second working valve position of the valve device (200), the electromagnet (42) is de-energized, and the first piston (44) disengages from the second piston (76) so that the control chamber (66) is fluidly connected to the central channel (80).

3. The valve device (200) according to claim 1 or 2, wherein, The valve device (200) also includes a solenoid valve (82), which is configured to close the air passage that connects the pilot chamber (60) to the external environment when de-energized and to open the air passage when energized. In the unactivated valve position of the valve device (200), the solenoid valve (82) is de-energized, and in the first and second working valve positions of the valve device (200), the solenoid valve (82) is energized.

4. The valve device (200) according to claim 3, wherein, The valve assembly (200) also includes a pressure sensor (84) configured to detect pressure in the control chamber (66). In the first working valve position of the valve assembly (200), when the detected pressure is greater than the desired braking pressure, the solenoid valve (82) is energized, and in the second working valve position of the valve assembly (200), when the detected pressure is equal to the ambient air pressure, the solenoid valve (82) is de-energized, so that the valve assembly (200) moves from the second working valve position to the inactive valve position.

5. The valve device (200) according to any one of claims 1 to 4, wherein, The electromagnet (42) includes: A first sleeve (46) extends from the first shaft end of the housing (40) into the housing (40), and a first piston (44) is slidably fitted onto the first sleeve (46); A groove (48) extending from the first shaft end of the first sleeve (46) away from the second shaft end of the first sleeve (46); The first spring (50) is received in the groove (48); An armature (52) disposed in the first sleeve (46) has its first shaft end at least partially received in a groove (48) to be pushed by a first spring (50), and its second shaft end abutting against a first piston (44); and A hollow magnetizing assembly is located between the first sleeve (46) and the armature (52). The hollow magnetizing assembly is configured to generate a magnetic force when the electromagnet (42) is energized. The magnetic force pushes the second shaft end of the armature (52) to extend out from the second shaft end of the first sleeve (46) and push the first piston (44) relative to the first sleeve (46).

6. The valve device (200) according to claim 5, wherein, An extension opening is formed at the second shaft end of the first sleeve (46) by the first sleeve (46) and / or the hollow magnetizing assembly. The diameter of the second shaft end of the armature (52) is smaller than the diameter of the rest of the armature (52), and the diameter of the extension opening is between the diameter of the second shaft end of the armature (52) and the diameter of the rest of the armature (52), so that only the second shaft end of the armature (52) is allowed to extend out from the extension opening.

7. The valve device (200) according to claim 6, wherein, The difference between the inner diameter of the hollow magnetizing assembly and the diameter of the second shaft end of the armature (52) is minimized.

8. The valve device (200) according to any one of claims 5 to 7, further comprising at least one of the following: The first piston (44) includes a cylindrical layer (44a) extending axially to slide in contact with the outer periphery of the first sleeve (46), the axial length of the cylindrical layer (44a) being equal to or less than the axial length of the outer periphery of the first sleeve (46). The first piston (44) includes an abutment ring (44b1) configured to abut against the second piston (76); and A stop (59) is provided in the housing (40) on one axial end face relative to the first spacer (56).

9. The valve device (200) according to any one of claims 1 to 8, wherein, The relay valve (70) also includes: A second sleeve (72) extends from the second shaft end of the housing (40) into the housing (40); and The second spring (74) is received in the second sleeve (72); The second piston (76) is slidably mounted on the second sleeve (72) and is pushed by the second spring (74).

10. A vehicle electronic braking system (100), comprising: Electronic control device (10); A single-channel electro-pneumatic modulator (16), a dual-channel electro-pneumatic modulator (24), and a trailer control valve device (26), wherein at least one of the single-channel electro-pneumatic modulator (16), the dual-channel electro-pneumatic modulator (24), and the trailer control valve device (26) includes a valve device (200) according to any one of claims 1 to 9, wherein the electronic control device (10) is configured to control the valve device (200).

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