JP2023148891A - Electromagnetic valve and brake control device - Google Patents

Abstract

To obtain, as one example, an electromagnetic valve which can suppress an influence of foreign matters to performance.SOLUTION: An electromagnetic valve of the present embodiment comprises, as one example: a coil; a plunger energized in a first direction by a magnetic field; a base having an outer face oriented toward the plunger, and formed with a hole extending in the first direction from the outer face; a movable member accommodated in the hole, and energized in the first direction by the plunger; a cylinder accommodated in the hole, and located between the inner face of the hole and the movable member; a support member having a first salient part which is salient from the cylinder to the inside of the cylinder in a position separated from the plunger in the first direction, and a second salient part which is salient from the cylinder to the outside of the cylinder in a position separated from the first salient part in a second direction opposite to the first direction, and located between the outer face and the plunger; and an elastic member located between the first salient part and the movable member, and energizing the movable member.SELECTED DRAWING: Figure 1

Description

Embodiments of the present invention relate to a solenoid valve and a brake control device.

In conventional brake control devices, a solenoid valve attracts a plunger with a magnetic field generated by an energized coil. For example, the plunger attracted by the magnetic field pushes the valve body in a direction in which the flow path is closed. Further, for example, a spring pushes the valve body in the direction in which the flow path opens (Patent Document 1).

Japanese Patent Application Publication No. 2011-503459

However, in conventional configurations, a sleeve press-fitted into a hole through which the valve body passes supports the spring. There is a possibility that foreign matter generated by press-fitting into the hole of the sleeve may affect the performance of the solenoid valve.

Therefore, the present invention has been made in view of the above, and provides a solenoid valve and a brake control device that can suppress the influence of foreign substances on performance.

As an example, a solenoid valve according to an embodiment of the present invention includes a coil that generates a magnetic field when a current is passed through it, a plunger that is biased in a first direction by the magnetic field, and an outer surface facing the plunger. , a base having a hole extending from the outer surface in the first direction, and biased in the first direction by the plunger at least partially received in the hole and biased by the magnetic field. a movable member; a tube that is at least partially accommodated in the hole and located between the inner surface of the hole and the movable member; and a tube that is spaced apart from the plunger in the first direction. a first protrusion that protrudes inward of the tube; and a first protrusion that protrudes from the tube to the outside of the tube at a position spaced apart from the first protrusion in a second direction opposite to the first direction; and a second protruding portion located between the first protruding portion and the movable member, the supporting member having a second protruding portion located between the first protruding portion and the movable member; and an elastic member. Therefore, for example, when assembling the electromagnetic valve, the support member is inserted into the hole from the end of the hole in the second direction substantially in the first direction. Therefore, even if foreign matter is generated due to contact between the base and the support member during assembly of the solenoid valve, the foreign matter will be generated between the cylinder and the inner surface of the hole, or between the second protrusion and the outer surface of the base. It's easy to stay in between. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

FIG. 1 is a sectional view showing a brake device according to a first embodiment. FIG. 2 is a sectional view showing a part of the base and the support member of the first embodiment. FIG. 3 is a sectional view showing the base, cylinder, and support part of the first embodiment along line F3-F3 in FIG. 1. FIG. 4 is a sectional view showing a part of the base and the support member during assembly of the first embodiment. FIG. 5 is a sectional view showing a part of the base and a support member according to the second embodiment. FIG. 6 is a sectional view showing a part of the base and the support member when the second embodiment is assembled. FIG. 7 is a sectional view showing a part of the base and a support member according to the third embodiment.

(First embodiment)
A first embodiment will be described below with reference to FIGS. 1 to 4. Note that, in this specification, a constituent element according to an embodiment and a description of the element may be described using a plurality of expressions. The components and their descriptions are examples and are not limited by the language in this specification. Components may also be identified by different names than herein. Also, components may be described using language that differs from that used herein.

FIG. 1 is a sectional view showing a brake device 10 according to a first embodiment. The brake device 10 is mounted on a vehicle 1 such as an automobile. Note that the brake device 10 is not limited to this example.

As shown in FIG. 1, the brake device 10 includes a master cylinder (M/C) 11, a wheel cylinder (W/C) 12, and a hydraulic pressure control device 13. The hydraulic control device 13 is an example of a brake control device. Note that the brake device 10 is not limited to this example.

A brake flow path 15 through which brake fluid flows is provided between the M/C 11 and the W/C 12. The hydraulic pressure control device 13 is provided between the M/C 11 and the W/C 12 in the brake flow path 15, and controls the pressure of brake fluid.

The hydraulic control device 13 includes a solenoid valve 21, a pump 22, and an ECU 23. The solenoid valve 21 is, for example, a differential pressure control valve in the hydraulic pressure control device 13. The hydraulic control device 13 further includes various components such as a pressure increase control valve, a pressure decrease control valve, a reservoir, a check valve, and a fixed displacement damper. The electromagnetic valve 21 is not limited to a differential pressure control valve, but may be a pressure increase control valve, a pressure decrease control valve, or another valve.

The electromagnetic valve 21 is provided in the brake flow path 15 between the M/C 11 and the W/C 12. Note that the brake flow path 15 may have a flow path that bypasses the electromagnetic valve 21. The electromagnetic valve 21 includes a housing 31 , a plunger 32 , a valve member 33 , a coil 34 , a spool 35 , a yoke 36 , and an elastic member 37 . The valve member 33 is an example of a movable member.

The solenoid valve 21 can be controlled, for example, into a communication state and a differential pressure state. In normal times when the driver operates the brake pedal of the vehicle 1, the electromagnetic valve 21 is in a communicating state with no current flowing through the coil 34. On the other hand, in the electromagnetic valve 21, when a current is passed through the coil 34, the plunger 32 and the valve member 33 are urged in the valve closing direction by the magnetic field generated by the coil 34. Thereby, the electromagnetic valve 21 functions like a relief valve and enters a differential pressure state. The differential pressure value generated by the solenoid valve 21 changes depending on the current value of the current flowing through the coil 34 of the solenoid valve 21.

The solenoid valve 21 in the differential state has a brake fluid pressure (hereinafter referred to as W/C pressure) at a portion connected to the W/C 12 via the brake flow path 15 (hereinafter referred to as the W/C 12 side). , when the brake fluid pressure (hereinafter referred to as M/C pressure) at the part connected to the M/C 11 via the brake flow path 15 (hereinafter referred to as the M/C 11 side) becomes higher than a predetermined value or more. Then, brake fluid is made to flow from the W/C 12 side to the M/C 11 side. Therefore, the solenoid valve 21 in the differential state maintains the W/C pressure so that it does not become higher than the M/C pressure by a predetermined value.

The structure of the solenoid valve 21 will be described in detail below. The housing 31 includes a base 41, a sheet 42, a sleeve 43, a filter 44, and a support member 45. That is, the base 41, the sheet 42, the sleeve 43, the filter 44, and the support member 45 are provided in the housing 31.

The base 41 is made of a magnetic material such as metal. The base 41 is formed into a substantially cylindrical shape extending along the central axis Ax. The central axis Ax passes approximately through the center of the base 41 and extends in the longitudinal direction of the base 41. Note that the central axis Ax may be offset from the center of the base 41.

In this specification, axial direction, radial direction, and circumferential direction are defined for convenience. The axial direction is a direction along the central axis Ax. The radial direction is a direction perpendicular to the central axis Ax. The circumferential direction is the direction of rotation around the central axis Ax. The axial direction is approximately equal to the longitudinal direction of the base 41.

The axial direction includes a first direction D1 and a second direction D2. The first direction D1 is one direction along the central axis Ax, and may also be referred to as the valve closing direction. The second direction D2 is the opposite direction to the first direction D1, and may also be referred to as the valve opening direction.

An inner hole 50 is provided inside the substantially cylindrical base 41 . The inner hole 50 extends along the central axis Ax and passes through the base 41 in the axial direction. Therefore, the inner hole 50 is open to the end surface 41a of the base 41 in the second direction D2 and the end surface 41b of the base 41 in the first direction D1. The end surface 41a is an example of an outer surface. Note that the outer surface is not limited to the end surface of the base.

The inner hole 50 has a first insertion hole 51 and a second insertion hole 52. The first insertion hole 51 is an example of a hole. The first insertion hole 51 and the second insertion hole 52 are each part of the inner hole 50. The first insertion hole 51 and the second insertion hole 52 communicate with each other in the axial direction.

The first insertion hole 51 opens in the end surface 41a of the base 41 and extends in the first direction from the end surface 41a. The second insertion hole 52 opens in the end surface 41b of the base 41, and communicates between the end surface 41b and the first insertion hole 51.

Each cross section of the first insertion hole 51 and the second insertion hole 52 perpendicular to the central axis Ax is formed, for example, into a substantially circular shape. The diameter of the second insertion hole 52 is shorter than the diameter of the first insertion hole 51. Note that the cross sections of each of the first insertion hole 51 and the second insertion hole 52 perpendicular to the central axis Ax may have other shapes such as a polygon.

The base 41 has an inner surface 51a of a first insertion hole 51 and an inner surface 52a of a second insertion hole 52. The inner surface 51a forms (defines, partitions) the first insertion hole 51. The inner surface 52a forms a second insertion hole 52. The inner surfaces 51a and 52a are formed into a substantially cylindrical shape extending in the axial direction. In other words, the inner surfaces 51a and 52a extend in the circumferential direction and face the central axis Ax.

A groove 55 is provided in the base 41. The groove 55 is provided on the inner surface 52a of the second insertion hole 52. The groove 55 extends substantially in the axial direction between the vicinity of the first insertion hole 51 and the vicinity of the end surface 41b of the base 41.

The sheet 42 is fitted into the second insertion hole 52 at a position spaced apart from the first insertion hole 51 in the first direction D1. Thereby, a space 56 is formed between the seat 42 and the end surface 41a in the axial direction. The space 56 includes at least a portion of the first insertion hole 51 and a portion of the second insertion hole 52 between the first insertion hole 51 and the sheet 42 . The groove 55 communicates the space 56 with the outside of the base 41 .

The sheet 42 is made of metal and has a substantially cylindrical shape. A first flow path 61 is provided inside the substantially cylindrical sheet 42 . The first channel 61 is an example of a channel. The first flow path 61 penetrates the sheet 42 in the axial direction along the central axis Ax. Therefore, the first flow path 61 and the inner hole 50 are arranged concentrically (coaxially).

The first flow path 61 opens to the end surface 42a of the sheet 42 in the second direction D2 and the end surface 42b of the sheet 42 in the first direction D1. The end surface 42 a faces the space 56 and the first insertion hole 51 . End surface 42b is located on the opposite side of end surface 42a. The first flow path 61 can communicate with the space 56 .

The first flow path 61 is provided with an orifice 61a. The orifice 61a is a portion whose cross section perpendicular to the central axis Ax is smaller than other portions of the first flow path 61. Further, the seat 42 has a substantially conical seat surface 42c that tapers from the end surface 42a toward the orifice 61a.

The sleeve 43 is opened in the first direction D1 and has a substantially cylindrical shape with a bottom. The sleeve 43 is made of, for example, a non-magnetic metal such as stainless steel. Note that the sleeve 43 is not limited to this example.

A portion of the base 41 including the end surface 41a is housed inside the sleeve 43. Sleeve 43 is secured to base 41 by welding or other means. Thereby, a storage chamber 62 that communicates with the first insertion hole 51 of the base 41 is provided inside the sleeve 43 .

The sleeve 43 has an inner peripheral surface 43a and a bottom surface 43b. The inner circumferential surface 43a is formed into a substantially cylindrical shape extending in the axial direction, and faces the central axis Ax. A portion of the inner peripheral surface 43a is fixed to the base 41, for example, by welding. The bottom surface 43b is a substantially hemispherical surface facing the end surface 41a of the base 41. Note that the shapes of the inner peripheral surface 43a and the bottom surface 43b are not limited to this example.

The inner peripheral surface 43a, the bottom surface 43b, and the end surface 41a of the base 41 form the storage chamber 62. Note that the accommodation chamber 62 is not limited to this example. The inner peripheral surface 43a, the bottom surface 43b, and the end surface 41a of the base 41 face toward the inside of the storage chamber 62.

The filter 44 is formed into a substantially cylindrical shape extending in the axial direction. For example, a portion of the base 41 including the end surface 41b is fitted into the filter 44. The filter 44 can collect foreign matter from the brake fluid passing through the filter 44 .

An internal flow path 15v through which brake fluid flows is provided inside the casing 31 described above. The internal flow path 15v includes the above-described first flow path 61 and second flow path 65. The second flow path 65 includes a groove 55 and a space 56. Therefore, the first flow path 61 and the second flow path 65 can communicate with each other.

The internal flow path 15v is connected to the M/C 11 and the W/C 12 through the brake flow path 15. The first flow path 61 is connected to the W/C 12 through the brake flow path 15. Furthermore, the first flow path 61 is connected to the pump 22 through the brake flow path 15 . The second flow path 65 is connected to the M/C 11 through the brake flow path 15. In this way, the first flow path 61 is on the W/C 12 side of the internal flow path 15v, and the second flow path 65 is on the M/C 11 side of the internal flow path 15v. The filter 44 is provided between the internal flow path 15v and the M/C 11.

The support member 45 is a different component from the base 41. Support member 45 is made of a material such as metal. The material of the support member 45 may be magnetic or non-magnetic. The support member 45 of the first embodiment is harder than the base 41. For example, the support member 45 is harder than the base 41 in at least one of Young's modulus, Brinell hardness, Rockwell hardness, and Knoop hardness, which can represent hardness or rigidity.

FIG. 2 is a sectional view showing a part of the base 41 and the support member 45 of the first embodiment. As shown in FIG. 2, the support member 45 includes a tube 70, a first protrusion 71, and a second protrusion 72. The second protrusion 72 may also be referred to as a flange. The tube 70, the first protrusion 71, and the second protrusion 72 are integrally formed. Note that the support member 45 is not limited to this example.

The cylinder 70 is formed into a substantially cylindrical shape extending in the axial direction. Note that the cylinder 70 may be formed in other shapes such as a polygonal cylinder. The tube 70 is at least partially accommodated in the first insertion hole 51 of the base 41 . The tube 70 of the first embodiment includes a first portion 75, a second portion 76, and a connecting portion 77.

Each of the first portion 75 and the second portion 76 is formed into a cylindrical shape extending in the axial direction. The first portion 75 is spaced apart from the second portion 76 in the second direction D2. Further, the first portion 75 is spaced apart from the end 70a of the tube 70 in the first direction D1 in the second direction D2. The connecting portion 77 is located between the first portion 75 and the second portion 76 and connects the first portion 75 and the second portion 76.

The first portion 75 has an outer surface 75a and an inner surface 75b. The outer surface 75a is an example of a fixed surface. The outer surface 75a and the inner surface 75b are formed into a cylindrical shape extending in the axial direction. The outer surface 75a faces radially outward. The inner surface 75b is located on the opposite side of the outer surface 75a and faces radially inward.

The first portion 75 is press-fitted into the first insertion hole 51 and fixed to the base 41. Therefore, the outer surface 75a is fixed to the inner surface 51a of the first insertion hole 51 by coming into contact with the inner surface 51a of the first insertion hole 51. Note that the first portion 75 may be fixed to the base 41 by other methods.

Second portion 76 has an outer surface 76a and an inner surface 76b. The outer surface 76a and the inner surface 76b are formed into a cylindrical shape extending in the axial direction. The outer surface 76a faces radially outward. The inner surface 76b is located on the opposite side of the outer surface 76a and faces radially inward.

The diameter of the outer surface 76a of the second portion 76 is shorter than the diameter of the outer surface 75a of the first portion 75. The outer surface 76a of the second portion 76 is spaced apart from the inner surface 51a of the first insertion hole 51. The diameter of the inner surface 76b of the second portion 76 is shorter than the diameter of the inner surface 75b of the first portion 75.

The thickness of the first portion 75 and the thickness of the second portion 76 are approximately constant. The thickness of the first portion 75 is the distance between the outer surface 75a and the inner surface 75b of the first portion 75 in the radial direction. The thickness of the second portion 76 is the distance between the outer surface 76a and the inner surface 76b of the second portion 76 in the radial direction.

The connecting portion 77 is formed into a substantially conical shape that tapers from the first portion 75 to the second portion 76 . Therefore, the tube 70 is spaced apart from the inner surface 51a of the first insertion hole 51 between the end 70a of the tube 70 and the outer surface 75a of the first portion 75 in the first direction D1. Note that the connecting portion 77 may be formed in other shapes.

The first protrusion 71 protrudes from the end 70a of the cylinder 70 to the inside of the cylinder 70. Note that the first protrusion 71 may be provided at a position spaced apart from the end 70a of the tube 70 in the second direction D2. However, the first protrusion 71 is spaced apart in the first direction D1 from the end 70b of the cylinder 70 in the second direction D2.

In this embodiment, the first protrusion 71 protrudes radially inward from the cylinder 70. In other words, the first protrusion 71 protrudes from the tube 70 in a direction substantially perpendicular to the central axis Ax. Note that the first protrusion 71 may protrude in another direction diagonally intersecting the central axis Ax as long as it is inside the cylinder 70.

The first protrusion 71 is formed in an annular shape that protrudes from the entire circumferential area (entire circumference) of the inner surface 76b of the second portion 76. Note that the first protrusion portion 71 may include a plurality of portions that protrude from the tube 70 and are spaced apart from each other in the circumferential direction.

The first protrusion 71 is located in the first insertion hole 51 . As shown in FIG. 1, the first protrusion 71 is spaced apart from the sheet 42 in the second direction D2. In the axial direction, the first protrusion 71 is located between the first flow path 61 provided in the seat 42 and the end surface 41a of the base 41.

As shown in FIG. 2, the second protrusion 72 protrudes from the end 70b of the cylinder 70 to the outside of the cylinder 70. In other words, the second protrusion 72 protrudes from the tube 70 at a position spaced apart from the first protrusion 71 in the second direction D2.

In this embodiment, the second protrusion 72 protrudes radially outward from the tube 70. In other words, the second protrusion 72 protrudes from the tube 70 in a direction substantially perpendicular to the central axis Ax. Note that the second protrusion 72 may protrude in another direction diagonally intersecting the central axis Ax as long as it is outside the tube 70.

The second protrusion 72 is formed in an annular shape that protrudes from the entire area of the outer surface 75a of the first portion 75 in the circumferential direction. Note that the second protruding portion 72 may include a plurality of portions that protrude from the tube 70 and are spaced apart from each other in the circumferential direction.

The outer diameter of the second protrusion 72 is longer than the diameter of the first insertion hole 51. Furthermore, the outer diameter of the second protrusion 72 is shorter than the diameter of the inner peripheral surface 43a of the sleeve 43. Therefore, the second protrusion 72 is spaced radially inward from the sleeve 43.

The second protrusion 72 is located outside the first insertion hole 51 . An end surface 41 a of the base 41 faces the second protrusion 72 . In the first embodiment, the end surface 41 a may be in contact with the second protrusion 72 or may be spaced apart from the second protrusion 72 .

The plunger 32 shown in FIG. 1 is made of a magnetic material such as metal, and has a substantially cylindrical shape extending along the central axis Ax. The plunger 32 is housed in the housing chamber 62 of the sleeve 43. Therefore, the plunger 32 is housed in the housing 31 at a position spaced apart from the seat 42 in the second direction D2. Plunger 32 has a side surface 32a, an end surface 32b, and an end surface 32c.

The side surface 32a is a substantially cylindrical surface extending in the axial direction. Note that the center of the side surface 32a may be slightly shifted from the central axis Ax. The side surface 32a faces the inner peripheral surface 43a of the sleeve 43. The diameter of the side surface 32a is slightly shorter than the diameter of the inner peripheral surface 43a of the sleeve 43.

The side surface 32a of the plunger 32 is supported by the inner circumferential surface 43a of the sleeve 43 so as to be movable in the axial direction with respect to the housing 31. In other words, the plunger 32 is guided in the axial direction by the inner peripheral surface 43a of the sleeve 43.

For example, the inner circumferential surface 43a of the sleeve 43 limits movement of the plunger 32 in the radial direction by abutting a part of the side surface 32a. Further, the inner peripheral surface 43a is slightly spaced apart from the other part of the side surface 32a, thereby allowing the plunger 32 to move smoothly in the axial direction.

The end surface 32b is the end surface of the plunger 32 in the first direction D1. Note that the plunger 32 may have a portion protruding from the end surface 32b in the first direction D1. The end surface 32b is formed substantially flat and faces in the first direction D1. Note that the end surface 32b is not limited to this example, and may have other shapes. The end surface 32b of the plunger 32 and the end surface 41a of the base 41 face each other with a gap therebetween. Further, the end surface 32b faces the end surface 42a of the sheet 42 via the base 41.

The second protrusion 72 of the support member 45 is located between the end surface 41 a of the base 41 and the end surface 32 b of the plunger 32 . Therefore, the end surface 32b of the plunger 32 faces the second protrusion 72. The distance between the second protrusion 72 and the end surface 41a of the base 41 is shorter than the distance between the second protrusion 72 and the end surface 32b of the plunger 32.

End surface 32c is located on the opposite side of end surface 32b. The end surface 32c is the end surface of the plunger 32 in the second direction D2. Note that the end surface 32c is not limited to this example. The end surface 32c faces the bottom surface 43b of the sleeve 43.

The valve member 33 is made of a non-magnetic material such as synthetic resin, for example. The valve member 33 is located between the seat 42 and the plunger 32 and is housed in the housing 31. Valve member 33 is axially movable relative to seat 42 . The valve member 33 has a shaft 81 and a valve body 82.

The shaft 81 passes through the inside of the cylinder 70 of the support member 45 and the first protrusion 71 and extends substantially in the axial direction. Therefore, the cylinder 70 is located between the inner surface 51a of the first insertion hole 51 and the valve member 33. The shaft 81 has a support portion 85 and an extension portion 86 . The support portion 85 and the extension portion 86 are integrally formed. The support portion 85 and the extension portion 86 are formed in a substantially cylindrical shape extending in the axial direction along the central axis Ax.

FIG. 3 is a sectional view showing the base 41, cylinder 70, and support part 85 of the first embodiment along the line F3-F3 in FIG. As shown in FIG. 3, the support portion 85 has a plurality of curved surfaces 85a and a plurality of flat surfaces 85b.

Each of the plurality of curved surfaces 85a is an arcuate curved surface extending substantially in the circumferential direction. The plurality of curved surfaces 85a have a common center extending in the axial direction. Each of the plurality of planes 85b is formed substantially flat and faces substantially in the radial direction. The plurality of curved surfaces 85a and the plurality of flat surfaces 85b are provided alternately in the circumferential direction. The plurality of curved surfaces 85a and the plurality of flat surfaces 85b are formed, for example, by cutting out the outer surface of the substantially cylindrical support portion 85 extending in the axial direction. Note that the plurality of curved surfaces 85a and the plurality of flat surfaces 85b are not limited to this example.

At least a portion of the support portion 85 is located inside the first portion 75 of the tube 70 . The diameter of the curved surface 85a of the support portion 85 is shorter than the diameter of the inner surface 75b of the first portion 75. Therefore, a gap is provided between the curved surface 85a of the support portion 85 and the inner surface 75b of the first portion 75. The first portion 75 can support the support portion 85 movably in the axial direction. In other words, the first portion 75 guides the support portion 85 in the axial direction.

As shown in FIG. 1, the support portion 85 has end faces 85c and 85d. The end surface 85c is provided at the end of the support portion 85 in the first direction D1, and faces in the first direction D1. The end surface 85d is located on the opposite side of the end surface 85c. The end surface 85d is provided at the end of the support portion 85 in the second direction D2, and faces in the second direction D2.

The extending portion 86 extends from the end surface 85c of the support portion 85 in the first direction D1 through the inner side of the tube 70 and the first protruding portion 71. The outer diameter of the extending portion 86 inside the first protrusion 71 is shorter than the inner diameter of the first protrusion 71 . Therefore, the extending portion 86 is spaced apart from the first protruding portion 71.

The difference between the outer diameter of the extending portion 86 and the inner diameter of the first protrusion 71 is larger than the difference between the diameter of the curved surface 85a and the diameter of the inner surface 75b of the first portion 75. Therefore, even when the support portion 85 comes into contact with the inner surface 75b of the first portion 75, the extension portion 86 remains spaced apart from the first protrusion portion 71.

The outer diameter of the extended portion 86 is shorter than the minimum width of the support portion 85 in the radial direction. Therefore, the end surface 85c of the support portion 85 is exposed. An end surface 85c of the support portion 85 faces the first protrusion 71.

The valve body 82 is formed, for example, into a substantially hemispherical shape. Note that the shape of the valve body 82 is not limited to this example. The valve body 82 is located in the space 56 and provided at the end of the extending portion 86 in the first direction D1. The valve body 82 can move in the axial direction together with the shaft 81.

The end surface 85d of the support portion 85 contacts the end surface 32b of the plunger 32. Therefore, the shaft 81 can move integrally with the plunger 32 in the axial direction. Note that the shaft 81 may be fixed to the plunger 32.

The valve member 33 is movable in the axial direction between a closed position Pc and an open position Po. In FIG. 1, the valve member 33 located in the closed position Pc is shown with a chain double-dashed line, and the valve member 33 located in the open position Po is shown with a solid line.

When the valve member 33 is located in the closed position Pc, the valve body 82 closes the first flow path 61 by contacting the seat surface 42c of the seat 42. In other words, when the valve member 33 is located in the closed position Pc, the valve body 82 blocks the first flow path 61 and the second flow path 65 by contacting the seat surface 42c.

When the valve member 33 is located at the open position Po, the valve body 82 is separated from the seating surface 42c of the seat 42. Thereby, the valve body 82 opens the first flow path 61 and allows the first flow path 61 to communicate with the second flow path 65 . The closed position Pc is a position spaced apart from the open position Po in the first direction D1.

As shown in FIG. 1, the coil 34 is, for example, a solenoid wound around the central axis Ax. The coil 34 is located outside the sleeve 43 and surrounds the sleeve 43. The coil 34 generates a magnetic field by passing a current through it. The ECU 23 controls the current flowing to the coil 34.

The spool 35 is made of, for example, a non-magnetic material such as resin, and has a substantially cylindrical shape. Coil 34 is housed in spool 35. A sleeve 43 is inserted inside the spool 35. Yoke 36 is made of magnetic material. The yoke 36 holds the spool 35 and the coil 34 and is attached to the housing 31.

The elastic member 37 is, for example, a coil spring wound around the central axis Ax. Note that the elastic member 37 may be another elastic body. The elastic member 37 is arranged inside the tube 70.

An extension 86 extends through the inside of the elastic member 37. The inner diameter of the elastic member 37 is longer than the outer diameter of the extending portion 86. The elastic member 37 is located between the tube 70 and the extending portion 86 in the radial direction. The elastic member 37 is spaced apart from the tube 70 and the extending portion 86.

The elastic member 37 is located between the first protrusion 71 and the end surface 85c of the support portion 85 in the axial direction. In other words, the elastic member 37 is located between the first protrusion 71 and the valve member 33.

The elastic member 37 is supported by the first protrusion 71 and the end surface 85c of the support part 85, and is compressed between the first protrusion 71 and the support part 85. Therefore, the elastic member 37 is supported by the first protrusion 71 and urges the valve member 33 in the second direction D2 by its elastic force. As the valve member 33 urged by the elastic member 37 moves in the second direction D2, the valve body 82 is separated from the seat 42. That is, the elastic member 37 urges the valve member 33 toward the open position Po with elastic force.

When the valve member 33 biased by the elastic member 37 moves in the second direction D2, the plunger 32 also moves integrally with the valve member 33 in the second direction D2. The first protrusion 71 is provided at a position spaced apart from the plunger 32 in the first direction D1, and supports the elastic member 37 that pushes the plunger 32 in the second direction D2 via the valve member 33.

When the valve member 33 moves to the open position Po, the end surface 32c of the plunger 32 comes into contact with the bottom surface 43b of the sleeve 43. The bottom surface 43b supports the plunger 32 and limits further separation of the plunger 32 from the seat 42 when the valve member 33 is in the open position Po.

The ECU 23 can control the W/C pressure generated in each W/C 12 by controlling the solenoid valve 21 and the pump 22. In normal times, the ECU 23 does not apply current to the coil 34. The valve member 33 is biased by the elastic member 37 and is located at the open position Po. As a result, the solenoid valve 21 is brought into communication.

In the solenoid valve 21 in the communicating state, the first flow path 61 communicates with the second flow path 65 . In other words, the solenoid valve 21 opens, and the brake flow path 15 on the M/C 11 side and the brake flow path 15 on the W/C 12 side communicate with each other. Therefore, brake fluid can flow between the M/C 11 side and the W/C 12 side.

When the brake pedal of the vehicle 1 is depressed, brake fluid flows from the M/C 11 to the W/C 12 through the first flow path 61. On the other hand, when the depression of the brake pedal is stopped, the brake fluid is quickly returned from the W/C 12 to the M/C 11 through the first flow path 61.

On the other hand, when the pressure of the W/C 12 is increased by the pump 22, the ECU 23 drives the pump 22 and controls the solenoid valve 21 to a differential pressure state. The ECU 23 causes the coil 34 to generate a magnetic field by passing a current through the coil 34.

The coil 34 generates a magnetic field to attract the plunger 32 in the first direction D1 by electromagnetic force. In other words, the plunger 32 is urged in the first direction D1 by the magnetic field generated by the coil 34.

When the coil 34 generates a magnetic field, magnetic flux flows through the end surface 41a of the base 41 and the end surface 32b of the plunger 32. Thereby, the plunger 32 is attracted to the end surface 41a. When the material of the support member 45 is magnetic, the magnetic flux flows through the second protrusion 72 . When the material of the support member 45 is a non-magnetic material, the thickness of the second protrusion 72 is set such that magnetic flux can flow through the end surface 41a of the base 41 and the end surface 32b of the plunger 32. Ru.

The plunger 32 attracted by the magnetic field pushes the valve member 33 in the first direction D1 and brings the valve body 82 closer to the seating surface 42c of the seat 42. In this way, the valve member 33 is biased in the first direction D1 by the plunger 32 biased by the magnetic field.

Pump 22 is connected to first flow path 61 via brake flow path 15 . The brake fluid discharged by the pump 22 flows into the first flow path 61 from the brake flow path 15 on the W/C 12 side. The brake fluid is ejected from the first flow path 61 toward the valve body 82 of the valve member 33 .

The brake fluid pushes the valve element 82 of the valve member 33, which is energized by the magnetic field of the coil 34, in the second direction D2. The brake fluid separates the valve body 82 from the seat surface 42c of the seat 42, passes through the gap between the valve body 82 and the seat surface 42c, and enters the space 56 of the second flow channel 65 from the first flow path 61. Inflow.

The attractive force generated by the magnetic field biases the valve member 33 in the first direction D1, while the reaction force generated by the brake fluid and the elastic member 37 biases the valve member 33 in the second direction D2. The valve member 33 moves to a position where the suction force and the reaction force are balanced, and adjusts the degree of opening of the first flow path 61 (valve opening degree). The ECU 23 adjusts the position of the valve member 33 and the pressure in the W/C 12 by adjusting the current flowing through the coil 34.

The ECU 23 may control the solenoid valve 21 to be in a closed state. That is, the ECU 23 applies current to the coil 34 to urge the plunger 32 and the valve member 33 in the first direction D1. By moving the valve member 33 to the closed position Pc, the valve body 82 closes the first flow path 61. When the valve member 33 is in the closed position Pc, the end surface 32b of the plunger 32 is spaced apart from the second protrusion 72.

FIG. 4 is a sectional view showing a part of the base 41 and the support member 45 during assembly of the first embodiment. As described above, the first portion 75 of the support member 45 is press-fitted into the first insertion hole 51 and fixed to the base 41. Therefore, when assembling the solenoid valve 21, the diameter of the outer surface 75a of the first portion 75 is slightly longer than the diameter of the inner surface 51a of the first insertion hole 51.

The support member 45 is inserted into the first insertion hole 51 from the end surface 41 a of the base 41 . The diameter of the outer surface 76a of the second portion 76 of the cylinder 70 is shorter than the diameter of the inner surface 51a of the first insertion hole 51. Therefore, the second portion 76 can be inserted into the first insertion hole 51 while being spaced apart from the inner surface 51a.

When the first portion 75 is press-fitted into the first insertion hole 51, the first portion 75 scrapes the base 41. As a result, foreign matter O such as a piece of the base 41 may be generated. When the first portion 75 is scraped, foreign matter O is generated, for example, in the gap G between the outer surface 76a of the second portion 76 and the inner surface 51a of the first insertion hole 51.

As shown in FIG. 2, in the axial direction, the length between the end 70a of the tube 70 and the outer surface 75a of the first portion 75 is longer than the length of the outer surface 75a. In other words, in the axial direction, the length of the gap G is longer than the length of the outer surface 75a. Therefore, the foreign matter O is difficult to flow out from the gap G and tends to remain in the gap G. In other words, the solenoid valve 21 can hold the generated foreign matter O in the gap G. Further, the outer surface 75a may be formed rougher than the inner surface 75b or may have irregularities so that the foreign matter O can be easily held.

If the foreign object O is caught between the side surface 32a of the plunger 32 and the inner circumferential surface 43a of the sleeve 43, it may become difficult for the plunger 32 to move in the axial direction. If the foreign object O is caught between the shaft 81 and the cylinder 70, there is a possibility that the valve member 33 will be difficult to move in the axial direction. Furthermore, if the foreign matter O is located between the valve body 82 and the seat surface 42c, there is a possibility that the valve body 82 will be difficult to block the first flow path 61. However, in the solenoid valve 21 of the present embodiment, by holding the foreign matter O in the gap G, there is a gap between the plunger 32 and the sleeve 43, between the shaft 81 and the cylinder 70, and between the valve body 82 and the seat surface 42c. It is possible to suppress foreign matter O from being caught in between.

The distance C1 between the outer surface 76a of the second portion 76 and the inner surface 51a of the first insertion hole 51 shown in FIG. 2 is the maximum distance between the curved surface 85a and the inner surface 75b of the first portion 75 shown in FIG. is shorter than the distance C2. The distance C2 is the distance between the other curved surface 85a and the inner surface 75b when the valve member 33 moves in the radial direction with respect to the support member 45 and one curved surface 85a abuts the inner surface 75b of the first portion 75. is the maximum distance.

If a foreign object O whose width is larger than the distance C2 is caught between the curved surface 85a and the inner surface 75b, there is a possibility that the valve member 33 becomes difficult to move in the axial direction. However, since the distance C1 is shorter than the distance C2, the foreign object O having a width larger than the distance C2 is held between the outer surface 76a of the second portion 76 and the inner surface 51a of the first insertion hole 51. Therefore, the solenoid valve 21 can suppress the foreign matter O that obstructs the movement of the valve member 33 in the axial direction from flowing out from the gap G.

In the hydraulic pressure control device 13 according to the first embodiment described above, the support member 45 includes a cylinder 70, a first protrusion 71, and a second protrusion 72. The cylinder 70 is at least partially accommodated in the first insertion hole 51 of the base 41 and located between the inner surface 51 a of the first insertion hole 51 and the valve member 33 . The first protrusion 71 protrudes inward from the cylinder 70 at a position spaced apart from the plunger 32 in the first direction D1. The second protrusion 72 protrudes from the tube 70 to the outside of the tube 70 at a position spaced apart from the first protrusion 71 in a second direction D2 opposite to the first direction D1, and extends from the end surface of the base 41. 41a and the plunger 32. According to the above configuration, when assembling the solenoid valve 21, the support member 45 is moved from the end of the first insertion hole 51 in the second direction D2 to the inside of the first insertion hole 51 in approximately the first direction. It will be inserted into D1. Therefore, even if foreign matter O is generated due to contact between the base 41 and the support member 45 during assembly of the solenoid valve 21, the foreign matter O will be between the cylinder 70 and the inner surface 51a of the first insertion hole 51. , or easily stay between the second protrusion 72 and the end surface 41a of the base 41. Therefore, the solenoid valve 21 can prevent the foreign matter O from affecting the performance of the solenoid valve 21.

The tube 70 has an outer surface 75a. The outer surface 75a is provided at a position spaced apart in the second direction D2 from the end 70a of the tube 70 in the first direction D1, and is in contact with the inner surface 51a of the first insertion hole 51, so that the outer surface 75a closes the first insertion hole 51. is fixed to the inner surface 51a of. That is, the outer surface 75a is fixed to the inner surface 51a of the first insertion hole 51, for example, by press fitting. The tube 70 is separated from the inner surface 51a of the first insertion hole 51 between the end 70a of the tube 70 in the first direction D1 and the outer surface 75a. As a result, even if a foreign object O is generated due to the press-fitting of the outer surface 75a during assembly of the solenoid valve 21, the foreign object O will be removed from the outer surface 75a between the end 70a of the cylinder 70 and the outer surface 75a in the first direction D1. It tends to stay in the gap G between the inner surface 51a of the first insertion hole 51 or between the second protrusion 72 and the end surface 41a of the base 41. Therefore, the solenoid valve 21 can prevent the foreign matter O from affecting the performance of the solenoid valve 21. Further, since the support member 45 is fixed to the base 41, the support member 45 can be prevented from coming into contact with the valve member 33 or the elastic member 37 and preventing movement of the valve member 33 or contraction of the elastic member 37.

Support member 45 is harder than base 41. Therefore, when the support member 45 is press-fitted into the first insertion hole 51 during assembly of the electromagnetic valve 21, the base 41 is scraped and foreign matter O is generated. In this case, the foreign object O enters the gap G between the tube 70 and the inner surface 51a of the first insertion hole 51 between the end 70a and the outer surface 75a of the tube 70 in the first direction D1, and enters the gap G between the tube 70 and the inner surface 51a of the first insertion hole 51. Stay in. Therefore, the solenoid valve 21 can prevent the foreign matter O from affecting the performance of the solenoid valve 21.

(Second embodiment)
A second embodiment will be described below with reference to FIGS. 5 and 6. In addition, in the description of multiple embodiments below, components having the same functions as already described components are given the same reference numerals as the already described components, and further explanation may be omitted. . Furthermore, the plurality of components labeled with the same reference numerals do not necessarily have all functions and properties in common, and may have different functions and properties depending on each embodiment.

FIG. 5 is a sectional view showing a part of the base 41 and the support member 45 according to the second embodiment. FIG. 6 is a sectional view showing a part of the base 41 and the support member 45 during assembly of the second embodiment. In the second embodiment, the support member 45 is softer than the base 41.

As shown in FIG. 6, when the first portion 75 is press-fitted into the first insertion hole 51, the base 41 scrapes the first portion 75. As a result, foreign matter O such as a piece of the support member 45 may be generated. When the first portion 75 is scraped, foreign matter O is generated, for example, between the end surface 41a of the base 41 and the second protrusion 72.

As shown in FIG. 5, when the press-fitting of the support member 45 is completed, the end surface 41a of the base 41 and the second protrusion 72 crush the foreign object O between them and hold the foreign object O. Therefore, the foreign matter O is difficult to flow out from between the end surface 41 a of the base 41 and the second protrusion 72 and tends to remain between the end surface 41 a of the base 41 and the second protrusion 72 .

The second protrusion 72 is spaced apart from the end surface 41a of the base 41. However, since the first portion 75 is press-fitted into the inner surface 51a of the first insertion hole 51, the support member 45 is fixed to the base 41.

In the hydraulic pressure control device 13 of the second embodiment described above, the support member 45 is softer than the base 41. Therefore, when the support member 45 is press-fitted into the first insertion hole 51 during assembly of the electromagnetic valve 21, the support member 45 is scraped and foreign matter O is generated. In this case, the foreign matter O enters between the second protrusion 72 and the end surface 41 a of the base 41 and remains between the second protrusion 72 and the end surface 41 a of the base 41 . Therefore, the solenoid valve 21 can prevent the foreign matter O from affecting the performance of the solenoid valve 21.

The second protrusion 72 protrudes from the entire circumference of the cylinder 70 to the outside of the cylinder 70 . Thereby, the second protrusion 72 can more reliably hold the foreign object O between the second protrusion 72 and the end surface 41a of the base 41.

(Third embodiment)
A third embodiment will be described below with reference to FIG. 7. FIG. 7 is a sectional view showing a part of the base 41 and the support member 45 according to the third embodiment. As shown in FIG. 7, the support member 45 of the second embodiment has a tube 170 instead of the tube 70. Tube 170 is substantially identical to tube 70, except as described below.

The cylinder 170 is formed into a cylindrical shape extending in the axial direction. The tube 170 has an outer surface 170a and an inner surface 170b. The outer surface 170a and the inner surface 170b are formed into a cylindrical shape extending in the axial direction between the end 70a of the tube 170 in the first direction D1 and the end 70b of the tube 170 in the second direction D2. The outer surface 170a faces radially outward. Inner surface 170b is located opposite outer surface 170a and faces radially inward.

The diameter of the outer surface 170a is shorter than the diameter of the inner surface 51a of the first insertion hole 51. The outer surface 170a is spaced apart from the inner surface 51a of the first insertion hole 51. Note that a part of the outer surface 170a may be in contact with the inner surface 51a of the first insertion hole 51.

In the third embodiment, the second protrusion 72 contacts the end surface 41a of the base 41. As the elastic member 37 biases the first protrusion 71 in the first direction D1, the second protrusion 72 is also biased in the first direction D1. The end surface 41 a of the base 41 supports the second protrusion 72 . Thereby, the end surface 41a of the base 41 and the elastic member 37 restrict movement of the support member 45 in the axial direction.

As described above, the diameter of the outer surface 170a is shorter than the diameter of the inner surface 51a of the first insertion hole 51. Further, the outer edge of the second protrusion 72 is spaced apart from the base 41 and the sleeve 43, for example. Therefore, the support member 45 is movable in the radial direction with respect to the base 41. The radial direction is an example of a direction orthogonal to the first direction.

In the third embodiment, the material of the base 41 is, for example, the same as the material of the support member 45. Therefore, the hardness of the support member 45 is approximately equal to the hardness of the base 41. Note that the support member 45 may be harder than the base 41 or may be softer than the base 41.

In the hydraulic pressure control device 13 of the third embodiment described above, the support member 45 is movable with respect to the base 41 in the radial direction orthogonal to the first direction D1. In other words, the support member 45 is not fixed to the base 41. On the other hand, the reaction force of the elastic member 37 urges the support member 45 in the first direction D1. The end surface 41 a of the base 41 supports the second protrusion 72 of the biased support member 45 . Thereby, the support member 45 can be attached to the base 41 without fixation such as press fitting. Since no press-fitting is required, the electromagnetic valve 21 can suppress generation of foreign matter O due to press-fitting during assembly. Therefore, the solenoid valve 21 can prevent the foreign matter O from affecting the performance of the solenoid valve 21.

The solenoid valve according to at least one embodiment described above includes, for example, a coil that generates a magnetic field when a current is passed through it, a plunger that is biased in a first direction by the magnetic field, and a coil that is directed toward the plunger. a base having an outer surface with an aperture extending from the outer surface in the first direction; and a base having an aperture extending from the outer surface in the first direction by the plunger being at least partially received in the aperture and biased by the magnetic field. a movable member that is biased; a tube that is at least partially housed in the hole and located between the inner surface of the hole and the movable member; and a tube that is spaced apart from the plunger in the first direction. a first protrusion that protrudes from the tube to the inside of the tube; and a first protrusion that protrudes from the tube to the outside of the tube at a position spaced apart from the first protrusion in a second direction opposite to the first direction. and a second protrusion located between the outer surface and the plunger; a support member located between the first protrusion and the movable member, the support member having an elastic member that biases in the direction of. Therefore, for example, when assembling the electromagnetic valve, the support member is inserted into the hole from the end of the hole in the second direction substantially in the first direction. Therefore, even if foreign matter is generated due to contact between the base and the support member during assembly of the solenoid valve, the foreign matter will be generated between the cylinder and the inner surface of the hole, or between the second protrusion and the outer surface of the base. It's easy to stay in between. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

In the above electromagnetic valve, for example, the cylinder is provided at a position spaced apart from the end of the cylinder in the first direction in the second direction, and comes into contact with the inner surface of the hole. It has a fixing surface fixed to an inner surface, and is spaced apart from the inner surface of the hole between the end of the tube in the first direction and the fixing surface. Therefore, for example, even if a foreign object is generated by press-fitting the fixed surface during assembly of a solenoid valve, the foreign object will be caused by the contact between the end of the cylinder and the inner surface of the hole in the first direction between the end of the cylinder and the fixed surface. or between the second protrusion and the outer surface of the base. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

In the above electromagnetic valve, for example, the support member is softer than the base. Therefore, for example, when a support member is press-fitted into a hole during assembly of a solenoid valve, the support member is scraped and foreign matter is generated. In this case, the foreign object enters between the second protrusion and the outer surface of the base and remains between the second protrusion and the outer surface of the base. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

In the above electromagnetic valve, for example, the support member is harder than the base. Therefore, for example, when a support member is press-fitted into a hole during assembly of a solenoid valve, the base is scraped and foreign matter is generated. In this case, the foreign matter enters the gap between the tube end and the fixed surface in the first direction, between the tube and the inner surface of the hole, and remains in the gap. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

In the electromagnetic valve, for example, the support member is movable relative to the base in a direction perpendicular to the first direction, and the outer surface supports the second protrusion. Therefore, as an example, the support member is not fixed to the base, while the support member is urged in the first direction by the reaction force of the elastic member. The outer surface of the base supports the second protrusion of the biased support member. Thereby, the support member can be attached to the base without fixation such as press fitting. Since no press-fitting is required, the electromagnetic valve can suppress the generation of foreign matter due to press-fitting during assembly. Therefore, the solenoid valve can prevent foreign matter from affecting the performance of the solenoid valve.

A brake control device according to at least one embodiment includes, for example, the electromagnetic valve provided with a flow path, and a pump connected to the flow path and capable of discharging brake fluid, and the movable member is movable between an open position in which the flow path is opened, and a closed position in which the flow path is closed while being separated from the open position in the first direction. Thus, by way of example, the solenoid valve can trap foreign objects between the barrel and the inner surface of the bore, or between the second protrusion and the outer surface of the base, thereby preventing the foreign objects from moving between the open and closed positions of the movable member. It can be suppressed from interfering with movement to and from the position. Therefore, the brake control device can suppress the influence of foreign matter on the performance of the brake control device.

In the above description, suppression is defined as, for example, preventing the occurrence of an event, effect, or effect, or reducing the degree of an event, effect, or effect. Furthermore, in the above explanation, restriction is defined as, for example, preventing movement or rotation, or allowing movement or rotation within a predetermined range and preventing movement or rotation beyond the predetermined range. .

Although the embodiments of the present invention have been illustrated above, the above embodiments and modifications are merely examples, and are not intended to limit the scope of the invention. The embodiments and modifications described above can be implemented in various other forms, and various omissions, substitutions, combinations, and changes can be made without departing from the gist of the invention. Furthermore, the configurations and shapes of each embodiment and each modification can be partially replaced.

13... Hydraulic pressure control device (brake control device), 21... Solenoid valve, 22... Pump, 32... Plunger, 33... Valve member (movable member), 34... Coil, 37... Elastic member, 41... Base, 41a... End face (Outer surface), 51... First insertion hole (hole), 51a... Inner surface, 61... First channel (channel), 70, 170... Cylinder, 70a... End, 71... First protrusion, 72 ...second protrusion, 75a...outer surface (fixed surface), D1...first direction, D2...second direction, Pc...closed position, Po...open position.

Claims (6)

A coil that generates a magnetic field when a current is passed through it,
a plunger biased in a first direction by the magnetic field;
a base having an outer surface facing the plunger and having a hole extending from the outer surface in the first direction;
a movable member at least partially housed in the hole and biased in the first direction by the plunger biased by the magnetic field;
a tube that is at least partially accommodated in the hole and located between the inner surface of the hole and the movable member; and a tube that projects inward from the tube at a position spaced apart from the plunger in the first direction. a first protrusion that protrudes from the cylinder to the outside of the cylinder at a position spaced apart from the first protrusion in a second direction opposite to the first direction, and that connects the outer surface and the plunger. a support member having a second protrusion located therebetween;
an elastic member located between the first protrusion and the movable member and urging the movable member in the second direction;
A solenoid valve equipped with. The tube is provided at a position spaced apart from the end of the tube in the first direction in the second direction, and is in contact with the inner surface of the hole, thereby fixing a fixing surface fixed to the inner surface of the hole. and spaced apart from the inner surface of the hole between the end of the cylinder and the fixing surface in the first direction,
The electromagnetic valve according to claim 1. the support member is softer than the base;
The electromagnetic valve according to claim 2. the support member is harder than the base;
The electromagnetic valve according to claim 2. The support member is movable relative to the base in a direction perpendicular to the first direction,
the outer surface supports the second protrusion;
The electromagnetic valve according to claim 1. The electromagnetic valve according to any one of claims 1 to 5, which is provided with a flow path;
a pump connected to the flow path and capable of discharging brake fluid;
Equipped with
The movable member is movable between an open position in which the flow path is opened, and a closed position in which the movable member is moved away from the open position in the first direction and closes the flow path.
Brake control device.

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