JP5371945B2 - Brake device - Google Patents

Description

  The present invention relates to a brake device having a reservoir function capable of storing brake fluid.

  The technology described in Patent Document 1 eliminates the wear ring and the like that are required in the case of metal by forming the piston for the reservoir in the brake device used in the anti-lock brake device etc. with resin. Yes.

JP 2006-151362 A

However, in the above prior art, there is a risk that abrasion, breakage, or the like may occur as the piston strength decreases.
The objective of this invention is providing the brake device provided with resin-made pistons excellent in durability.

In order to achieve the above object, the present invention comprises a piston body assembled in a bottomed hole formed in a housing, and a pressure regulating valve having a rod for separating the valve body from the seat portion, and an anti-lock brake A brake device having a reservoir function capable of storing brake fluid that has flowed out of a wheel cylinder of a vehicle into a bottomed hole when the piston body is stroked. A hard body harder than the resin was fixed to the surface, and the piston body and the rod were brought into contact with each other through the hard body.

  Therefore, it is possible to provide a brake device including a resin piston having excellent durability.

FIG. 2 is a hydraulic circuit diagram of the brake hydraulic pressure control device according to the first embodiment. 3 is an enlarged partial cross-sectional view illustrating a configuration of a reservoir according to Embodiment 1. FIG. FIG. 3 is a diagram illustrating a piston main body according to the first embodiment. It is the schematic showing the manufacturing process when insert-molding the piston main body of Example 1 with resin. It is an expanded partial sectional view showing a state when the piston main body of Example 1 reaches bottom dead center. 6 is an enlarged partial cross-sectional view illustrating a configuration of a reservoir according to Embodiment 2. FIG. 6 is a schematic diagram illustrating a piston main body of Example 3. FIG. 6 is an enlarged partial cross-sectional view illustrating a configuration of a reservoir according to Embodiment 4. FIG. It is an expanded partial sectional view showing the composition of the reservoir of other examples.

[Example 1]
[Configuration of brake hydraulic circuit]
FIG. 1 is a hydraulic circuit diagram of the brake hydraulic pressure control device 32 according to the first embodiment. The hydraulic circuit is formed in a hydraulic control unit 30 provided between the master cylinder M / C and the wheel cylinder W / C. The hydraulic control unit 30 has a substantially rectangular parallelepiped housing 31 cut out from an aluminum block. A plurality of oil passages and the like are formed in the housing 31, and each valve, pump unit, and motor described later are provided. .
The brake fluid pressure control device 32 performs fluid pressure control according to the required fluid pressure of the vehicle dynamics control (VDC: vehicle behavior control) and the anti-lock brake system (ABS: antilock brake control) from the controller. The brake fluid pressure control device 32 has an X piping structure composed of two systems of a P system brake fluid pressure circuit 21P and an S system brake fluid pressure circuit 21S. The left front wheel cylinder W / C (FL) and the right rear wheel wheel cylinder W / C (RR) are connected to the P system, and the right front wheel wheel cylinder W / C (FR) is connected to the S system. ), Wheel cylinder W / C (RL) for the left rear wheel is connected. The brake fluid pressure control device 32 and each wheel cylinder W / C are connected to wheel cylinder ports 19RL, 19FR, 19FL, 19RR drilled in the upper surface of the housing 31. The pump unit P is a tandem gear pump that drives a gear pump PP and a gear pump PS, each of which includes a pair of external gears provided in each of the P system and the S system, with a single motor M.

The master cylinder M / C and the hydraulic pressure control unit 30 are connected to each other in the liquid passages 18P and 18S via master cylinder ports 20P and 20S formed in the port connection surface of the housing 31. The liquid path 18 and the suction side of the pump unit P are connected by liquid paths 10P and 10S. On the liquid path 18P, a master cylinder pressure sensor 22 is provided between the master cylinder port 20P and a connection portion between the liquid path 10P.
The discharge side of the pump unit P and each wheel cylinder W / C are connected by liquid paths 11P and 11S. On each of the liquid passages 11, pressure increasing valves 3FL, 3RR, 3FR, 3RL, which are normally open solenoid valves corresponding to the respective wheel cylinders W / C, are provided. Further, check valves 6P and 6S are provided on each liquid passage 11 and between each pressure increasing valve 3 and the pump unit P. Each check valve 6 allows the flow of the brake fluid pressure in the direction from the pump unit P toward the pressure increasing valve 3 and prohibits the flow in the opposite direction. Discharge pressure sensors 23P and 23S are provided between the pressure increasing valves 3 and the pump unit P on each liquid passage 11.

Furthermore, each fluid passage 11 is provided with fluid passages 16FL, 16RR, 16FR, and 16RL that bypass each pressure increasing valve 3, and the fluid passage 16 is provided with check valves 9FL, 9RR, 9FR, and 9RL. Yes. Each check valve 9 allows the flow of brake fluid pressure in the direction from the wheel cylinder W / C toward the pump unit P, and prohibits the flow in the opposite direction.
The master cylinder M / C and the liquid path 11 are connected by liquid paths 12P and 12S, and the liquid path 11 and the liquid path 12 merge between the pump unit P and the pressure increasing valve 3. On each liquid passage 12, gate-out valves 2P and 2S, which are normally open solenoid valves, are provided. Each liquid path 12 is provided with liquid paths 17P and 17S that bypass each gate-out valve 2, and the liquid path 17 is provided with check valves 8P and 8S. Each check valve 8 allows the flow of brake fluid pressure in the direction from the master cylinder M / C side toward the wheel cylinder W / C, and prohibits the flow in the opposite direction. The master cylinder M / C and the reservoirs 15P and 15S are connected by liquid passages 10aP and 10aS, and pressure regulating valves 7P and 7S having a check valve function are provided between the reservoir 15 and the master cylinder M / C. Yes.
Reservoirs 15P and 15S are provided on the suction side of the pump unit P, and the reservoir 15 and the pump unit P are connected by liquid passages 10bP and 10bS.
The wheel cylinder W / C and the liquid path 10 are connected by liquid paths 13 </ b> P and 13 </ b> S, and the liquid path 13 and the liquid path 10 merge between the pressure regulating valve 7 and the reservoir 15. The liquid passages 13 are provided with pressure reducing valves 4FL, 4RR, 4FR, 4RL, which are normally closed solenoid valves.

  Here, the operation of the pressure regulating valve 7 provided adjacent to the reservoir 15 will be described. During normal braking, that is, when each valve, pump, etc. is not operating, if brake fluid pressure is generated in the master cylinder M / C, the pressure regulating valve 7 is closed and the master cylinder M / C and the reservoir 15 are shut off. . Then, the brake fluid is supplied to each wheel cylinder W / C through the fluid passage 18. Next, at the time of ABS operation, when the pressure increasing valve 3 is closed and the pressure reducing valve 4 is opened as an initial operation, the brake fluid in the wheel cylinder W / C flows into the reservoir 15 through the liquid passage 13. At this time, the brake fluid that has flowed into the reservoir 15 by the operation of the pump unit P is pumped up through the fluid path 11 and is returned to the master cylinder M / C. At the time of VDC operation, the gate-out valve 2 is closed, the pressure increasing valve 3 corresponding to the desired wheel is opened, and the pump unit P is operated. At this time, even if the pressure regulating valve 7 is closed, the inside of the reservoir 15 is decompressed by pumping up the pump unit P, and the pressure regulating valve 7 is pushed open. As a result, the brake fluid is pumped up from the master cylinder M / C, and the increased brake fluid is supplied to the necessary wheel cylinder W / C.

FIG. 2 is an enlarged partial cross-sectional view illustrating the configuration of the reservoir according to the first embodiment. A cylindrical bottomed hole 31 a is formed below the housing 31 upward. A retainer holding surface 31a2 is formed in the lower opening of the housing of the bottomed hole 31a, and the retainer holding surface 31a2 holds the retainer member 151 by caulking fixing 31a3. The retainer member 151 holds one end of a flange portion 151a whose outer peripheral edge is nipped by a caulking fixing 31a3, a cylindrical portion 151b that is bent downward from the flange portion 151a, and a coil spring 152 (first elastic member). The holding surface 151c is formed with a closed portion, and an air hole 151d is formed in the approximate center of the closed portion. Thus, the atmospheric pressure is always applied below the piston main body 153.
The bottomed hole 31a includes a piston contact surface 31a1 that contacts the piston surface 153h of the piston main body 153, and a small diameter cylindrical portion 31b that is smaller in diameter than the piston contact surface 31a1 and formed in the center of the bottomed hole 31a. Have. A liquid passage 13 communicating with the pressure reducing valve 4 and a liquid passage 10b communicating with the suction side of the pump unit P are connected to the small diameter cylindrical portion 31b. A cylindrical pressure regulating valve housing hole 31c having a central axis OR at a position offset from the central axis of the bottomed hole 31a, that is, the central axis OP of the piston main body 153, is formed further above the small diameter cylindrical portion 31b. . A liquid path 10a communicating with the master cylinder M / C is connected above the pressure regulating valve housing hole 31c.

A filter member 75 that removes impurities in the brake fluid that has flowed in from the fluid passage 10 a and a seat member 71 that constitutes the pressure control valve 7 while fitting with the filter member 75 are accommodated in the pressure regulating valve housing hole 31 c. Yes. In a region surrounded by the upper end of the seat member 71 and the filter member 75, a ball member 72 (valve element) and a pressure regulating valve return spring 73 (second valve) that urges the ball member 72 toward the seat member 71 side. (Elastic member) is attached. The elastic force of the pressure regulating valve return spring 73 is set to be weaker than the elastic force of the coil spring 152, and when the brake fluid pressure is not applied, the ball member 72 causes the rod 74 to move by the elastic force of the coil spring 152. It is set as the structure pushed up through.
The seat member 71 accommodates a rod 74 that contacts the ball member 72 at the center in the axial direction, and forms a brake fluid passage between the rod 74 and the outer periphery of the rod 74, and has a smaller diameter than the through hole 71b. A plurality of holes are formed at positions surrounding the holding hole 71d from below the sheet member 71, and a circulation hole 71c partially communicating with the lower end portion of the through hole 71b. A mortar-shaped sheet portion 71a is formed on the ball member 72 side of the through hole 71b. When the ball member 72 is seated on the seat portion 71a, the brake fluid does not flow between the liquid passage 10a and the small diameter cylindrical portion 31b. On the other hand, when the ball member 72 is pushed up against the force of the pressure regulating valve return spring 73 by the rod 74, the brake fluid supplied from the liquid passage 10 a passes through the filter of the filter member 75 and the through hole 71 b and the rod 74. It passes through the gap between the outer periphery and flows out from the flow hole 71c to the small diameter cylindrical portion 31b.

  The rod 74 is a rod-shaped metal member having a diameter larger than that of the holding hole 71d and being in contact with the ball member 72. The rod 74 is substantially the same diameter as the holding hole 71d and is longer than the rod front end 74a. The formed rod intermediate portion 74b has a tapered shape gradually reduced in diameter from the rod intermediate portion 74a and has a rod lower end portion 74c that comes into contact with an upper surface 155b of a plate member 155 described later. The rod 74 is configured as a separate member from the piston main body 153. When the piston main body 153 strokes more than the length of the rod intermediate portion 74b, the rod lower end 74c is separated from the plate member upper surface 155b. In other words, the rod tip 74a functions as a stopper by contacting the upper end of the holding hole 71d. As described above, the center axis OR of the rod 74 is arranged offset from the center axis OP (rotation center) of the piston main body 153.

The piston main body 153 is a resin-molded member, and is formed in a bottomed cylindrical shape having a bottom portion 153a1. On the outer periphery of the cylinder of the piston main body 153, there is an upper outer peripheral portion 153f formed slightly smaller than the inner peripheral diameter of the bottomed hole 31a, and an annular shape formed below the upper outer peripheral portion 153f to accommodate the annular seal member 154. A groove 153e, a seal member holding portion 153d formed to have substantially the same diameter as the inner diameter of the bottomed hole 31a and holding the annular seal member 154, and an inner circumference of the bottomed hole 31a formed below the seal member holding portion 153d A diameter-reduced portion 153 having a diameter smaller than that of the upper outer peripheral portion 153f and a weld line forming portion 153b formed below the reduced-diameter portion 153 and having substantially the same diameter as the inner peripheral diameter of the bottomed hole 31a. And have. The annular seal member 154 is partitioned with the upper part as a hydraulic chamber and the lower part as an air chamber.
Here, the weld line is a position away from the gate position (injection port for injecting molten resin into the mold) when resin molding (insert molding), and the resin flowing into the mold is another It is a portion that remains as a joint trace between the resins when they are cooled and solidified while joining with the resin that has flowed in through the path. In general, a portion where a weld line is formed tends to be less accurate. In the first embodiment, the weld line forming portion 153b is provided below the annular seal member 154, that is, at a position partitioned as an air chamber. That is, the piston main body 153 is configured so that the weld line is formed at a position where accuracy related to liquid tightness is not required, in other words, the weld line is not formed at a location where accuracy is required. .

An inner periphery 153a of the cylindrical portion of the piston main body 153 is formed to have a slightly larger diameter than the coil spring 152, and the other end of the coil spring 152 is held at the bottom portion 153a1. A metal plate member 155 is assembled by insert molding as a hard body harder than the resin of the piston main body 153 in the central region (that is, the crown surface 153j) of the piston surface 153h formed on the upper surface of the piston main body 153. ing. The plate member 155 is a disk-shaped stainless steel member, and the outer diameter DP of the plate member 155 is larger than the outer diameter DS of the coil spring 152.
That is, when the coil spring 152 is held by the bottom portion 153a1 of the resin-made piston main body 153, an elastic force by the coil spring 152 is always applied to the portion. If the outer diameter of the metal plate member 155 is smaller than the outer diameter of the coil spring 152, the contact position of the coil spring 152 and the plate member 155 are separated in the radial direction when viewed from the axial direction. Further, the shearing force acts on the crown surface 153j, and there is a possibility that durability is lowered. On the other hand, as in the first embodiment, if the outer diameter DP of the plate member 155 is larger than the outer diameter DS of the coil spring 152, the contact position of the coil spring 152 and the plate member 155 have a diameter when viewed from the axial direction. It overlaps seeing from an axial direction, without separating in a direction. Therefore, only the compression force acts on the crown surface 153j, and the decrease in durability is suppressed.

  FIG. 3 is a diagram illustrating the piston body of the first embodiment. 3A is a top view, FIG. 3B is a side sectional view, and FIG. 3C is a bottom view. The plate member 155 is a member that is integrated by insert molding when the piston main body 153 is resin-molded, and two positioning holes 155c are provided on an axis passing through the center of the plate member 155. Further, four claw portions 153g that cover the plate member 155 from above are formed at equal intervals in the circumferential direction, thereby restricting separation between the plate member 155 and the piston main body 153. As shown in FIG. 3C, the gate position when the piston main body 153 is resin-molded is formed substantially at the center of the bottom 153a1. That is, the position where the molten resin smoothly flows into the position where accuracy is required, such as the annular groove 153e holding the annular seal member 154 and the crown surface, is the gate side where the accuracy is not required. It is arranged so that it is far from the position and difficult to wrap around. In addition, by setting the thickness of the weld line forming portion 153b to be thick, the molten resin flows relatively easily, and even if the molten resin is slightly cooled in the process of flowing, the weld line is not easily formed. Yes.

  When the piston main body 153 is accommodated in the bottomed hole 31a, the piston main body 153 is a cylindrical member and is rotatably accommodated about the central axis OP. For example, a rotational force is generated by a piston motion or the like accompanying the inflow of brake fluid or by vibrations transmitted from the vehicle body side. At this time, the rod 74 and the piston main body 153 have a separate structure. For example, even if the central axis OR of the rod 74 is offset from the central axis OP of the piston main body 153, the force that regulates in the rotational direction does not work. Therefore, the piston body 153 rotates. At this time, the rod lower end portion 74c of the rod 74 is in sliding contact with the circumference of the plate member 155 having a radius corresponding to the offset amount between the center axis OP and the center axis OR. That is, the rod 74 and the plate member 155 do not always come into contact with each other at the same position, but the piston body 153 makes contact while changing the contact position by appropriately rotating, so that uneven wear that only wears the same portion is suppressed. The durability of the plate member 155 can be improved.

FIG. 4 is a schematic diagram illustrating a manufacturing process when the piston body of Example 1 is insert-molded with resin. In the first embodiment, the first mold 201 which is the crown side mold, the second mold 202 and the third mold 203 which are installed on the upper surface of the first mold 201 and form the outer peripheral surface of the piston body. And a fourth mold 204 that forms a bottom portion 153a1 of the piston 153 and a cylindrical portion inner periphery 153a and has an injection port 204a for injecting molten resin.
As shown in STEP 1 of FIG. 4, the first mold 201 is provided with two locate pins 201 a inserted into the locate pin through holes 201 b, and these locate pins 201 a are inserted into the locate holes 155 c of the plate member 155. Thus, the plate member 155 is positioned. In this state, the second mold 202 and the third mold 203 are brought into close contact with the upper surface of the first mold 201 while moving from the left and right toward the center. In this state, the mold of the piston main body 153 is completed by covering the fourth mold 204 from above. In this state, molten resin is poured from the injection port 204a provided in the fourth mold 204, and insert molding is performed.
When the pouring of the molten resin is completed, in STEP 2, the fourth mold 204 is first moved upward and removed, and in STEP 3, the second mold 202 and the third mold 203 are moved to the left and right and removed, and finally in STEP 4. , The locating pin 201a is pushed up to remove the first mold 201 and the piston main body 153.

  FIG. 5 is an enlarged partial cross-sectional view illustrating a state when the piston body of the first embodiment reaches the bottom dead center. The bottom dead center means the lowest point at which the piston body cannot physically move further downward. At this time, when the axial distance L between the piston contact surface 31a1 and the piston surface 153h is compared with the size of the outer diameter DP of the plate member 155, DP> L. That is, the plate member 155 is insert-molded with respect to the piston main body 153 and operates integrally, but it is assumed that the plate member 155 is peeled off by any chance. Here, if it is configured so that DP <L, the plate member 155 can rise vertically at the bottom dead center, and in that state, between the crown surface and the bottom surface of the small diameter cylindrical portion 31b. If it is bitten, the piston body 153 may not be able to stroke. On the other hand, in the first embodiment, since DP> L, the plate member 155 cannot be lifted in the vertical direction even if the plate member 155 is dropped, and the piston body 153 can be stroked. The situation of disappearance can be avoided reliably. In the first embodiment, the axial distance L between the piston contact surface 31a1 and the piston surface 153h is shown, but more specifically, the distance between the crown surface 153j and the bottom of the small diameter cylindrical portion 31b is set as L. It is also effective to do. Since the plate member 155 has a disk shape, if the plate member 155 rises after being peeled off, the plate member 155 first comes into contact with the crown surface 153j and the bottom portion of the small diameter cylindrical portion 31b.

As described above, the effects listed below can be obtained in the first embodiment.
(1) A housing 31 in which an oil passage is formed, a piston main body 153 that is assembled in a bottomed hole 31a that is formed in the housing 31 and communicates with the liquid passages 10a, 10b, and 13 (oil passage); A coil spring 152 (first elastic member) that urges 153 toward the bottom of the bottomed hole 31a, a ball member 72 (valve element) disposed in the liquid passage 10a, and a seat portion 71a with which the ball member 72 abuts. The rod 74 is disposed between the crown surface 153j of the piston main body 153 and the ball member 72, and the rod 74 separates the ball member 72 from the seat portion 71a. The pressure regulating valve return spring 73 (second elastic member) having a weaker elastic force than the coil spring 152, the pressure regulating valve 7, and an anti-lock brake At the time of control, the piston body 153 has a reservoir function capable of storing the brake fluid that has flowed out of the wheel cylinder of the vehicle in the bottomed hole 31a, and the piston body 153 is resin-molded and the piston body 153 is crowned. A plate member 155 (hard body) harder than resin is provided on the surface 153j, and the piston main body 153 and the rod 74 are brought into contact with each other through the plate member 155.
Therefore, even if it is a case where it is set as the resin-made piston main body 153 in order to achieve weight reduction and cost reduction, the abrasion resistance with respect to the rod 74 of the crown surface 153j can be improved.

  (2) The hard body is a plate member 155 and is integrally formed with the piston main body 153. Therefore, it can manufacture simultaneously with resin molding of the piston main body 153, and can improve productivity. In the first embodiment, the plate member 155 is made of metal, but other hard materials can be appropriately selected without being limited to metal.

  (3) The plate member 155 has a disc shape, the first elastic member is a coil spring 152, the piston main body 153 is a member formed in a bottomed cylindrical shape having a bottom portion 153a1, and the coil spring 152 has a bottom portion 153a1. The diameter DP of the plate member 155 is larger than the outer diameter DS of the coil spring 152. Therefore, only the compressive force acts on the crown surface 153j, and a decrease in durability can be suppressed.

  (4) The maximum diameter DP of the plate member 155 is larger than the maximum stroke amount L of the piston body 153. Therefore, even if the plate member 155 is peeled off from the piston main body 153, the stroke of the piston main body 153 is not hindered and stable operation can be maintained.

  (5) The piston main body 153 is rotatably disposed in the bottomed hole 31a, and the rod 74 is disposed offset from the rotation center of the piston main body 153. That is, the rod 74 and the plate member 155 do not always come into contact with each other at the same position, but the piston body 153 makes contact while changing the contact position by appropriately rotating, so that the durability of the plate member 155 can be improved.

  (6) The annular groove 153e formed on the outer periphery of the piston main body 153 and the annular groove 153e are attached to seal between the inner peripheral surface of the bottomed hole 31a, and the hydraulic chamber and air are sealed in the bottomed hole 31a. An annular seal member 154 partitioned into a chamber, and a weld line forming portion 153b (weld line) in the air chamber region of the piston main body 153. That is, the piston main body 153 is configured so that the weld line is formed at a position where accuracy related to liquid tightness is not required, in other words, the weld line is not formed at a location where accuracy is required. Therefore, necessary accuracy can be ensured while improving productivity.

[Example 2]
Next, Example 2 will be described. Since the basic configuration is the same as that of the first embodiment, only different points will be described. FIG. 6 is an enlarged partial cross-sectional view illustrating the configuration of the reservoir according to the second embodiment. In Example 1, wear resistance was improved by integrally forming a metal plate member. On the other hand, in Example 2, the wear resistance is improved by applying a metal vapor deposition film to the crown surface. The crown surface 153k has a pedestal shape that is higher than the piston surface 153h. The surface of the crown surface 153k is coated with a vapor-deposited film 153m having high wear resistance. For example, a vapor deposition method having high wear resistance such as titanium nitride or diamond-like carbon is appropriately selected.
As described above, in the second embodiment, the following operational effects can be obtained.
(7) The hard body is a vapor deposition film 153m formed by vapor deposition on the crown surface 153k of the piston main body 153. Therefore, weight reduction can be achieved compared with a metal plate member while improving wear resistance. Moreover, even if it peels, since the operation | movement of piston main body 153 is not prevented, the stroke amount setting freedom degree to a bottom dead center can be improved.

Example 3
Next, Example 3 will be described. FIG. 7 is a schematic diagram illustrating a piston main body according to the third embodiment. In the first embodiment, a disk-shaped member is used as the plate member. However, the third embodiment is different in that a petal-shaped plate member 160 extending in four directions in the radial direction is used. The plate member 160 has four hook portions 161 that taper out in the radial direction at equal intervals on the circumference. Moreover, it has the locate hole 160c for positioning in two places. When insert molding is performed, the hook portion 161 is covered with the resin claw portion 153g1, and the metal plate portion is exposed in a circle to form the rod contact surface 160a. Thereby, the back surface 160b and the crown surface 153j of the plate member 160 are in close contact with each other, and are further fixed integrally by the claw portion 153g1. Here, the region required for the rod contact surface 160a is a region in which the radial distance at the position where the locate hole 160c is formed is equal to or longer than the length corresponding to the offset amount between the central axis OP and the central axis OR. Good. Therefore, while securing this region, it is possible to reduce the weight by making the metal portion as small as possible in other regions.

As described above, the following operational effects can be obtained in the third embodiment.
(8) The plate member 155 has a hook portion 161 (convex portion) on the outer peripheral edge of the annular disk, and is fixed integrally with the piston body by the hook portion 161. Therefore, wear resistance can be improved while achieving weight reduction. In addition, although the hook part 161 is expressed as a configuration extending from the annular disk, an unnecessary part is scraped off from the large annular disk toward the inner periphery (concave part), and the remaining part (between the concave part and the concave part) is scraped off. It can be said that it is the hook part 161.

Example 4
Next, Example 4 will be described. FIG. 8 is an enlarged partial cross-sectional view illustrating the configuration of the reservoir of the fourth embodiment. Since the basic configuration is the same as that of the first embodiment, parts having similar functions are denoted by the same reference numerals, and different points are denoted by different reference numerals.
The reservoir 15 of the first embodiment has a configuration in which the central axis DR of the rod 74 and the central axis DP of the piston body 153 are offset. In contrast, the first embodiment is different in that the central axis DR of the rod 74 and the central axis DP of the piston body 153 are arranged on the same axis. Moreover, in Example 1, the liquid path 10a was connected above the pressure regulation valve accommodation hole 31c. On the other hand, the second embodiment is different in that the inner diameter surface of the pressure regulating valve housing hole 31c has an enlarged diameter portion 31d, and the liquid passage 10a is connected to the enlarged diameter portion 31d from the side. . In the first embodiment, the liquid passages 13 and 10b are connected to the pressure regulating valve housing hole 31c. However, in the fourth embodiment, the liquid passage 13 or 10b is directly in the bottomed hole 31a and above the annular seal member 154a. It is different in that it is open. In the first embodiment, only one annular seal member is provided. However, the fourth embodiment is different in that the upper annular seal member 154a and the lower annular seal member 154b are provided. Accordingly, the circumferential groove is also different in that the upper annular groove 153e and the lower annular groove 153e1 are formed. In the first embodiment, the air hole 151d is formed below the retainer member 151. However, in the fourth embodiment, the cylindrical air hole 151d1 bent into a cylindrical shape is formed, and the holding performance of the coil spring 152 is improved. Is different.

Moreover, in Example 1, the rod 74 and the piston main body 153 were comprised as a different body. In contrast, the first embodiment is different in that the rod 74 and the piston main body 153 are integrally formed. Specifically, a rod holding hole 155p is provided at the center of the plate member 155, and the rod 74 is press-fitted so that the plate member 155 and the rod 74 are integrated. Next, after this integrated member is placed on the first mold 201, the piston main body 153 is formed by insert molding. Thereby, the improvement of assemblability can be aimed at. Further, since the rod 74 and the plate member 155 are always integrally operated by being integrally formed, it is not necessary to consider wear resistance, and durability can be improved.
Further, it is conceivable that the piston main body 153 is molded with resin, and at that time, the rod 74 is also integrally molded with resin. However, the rod 74 is an elongated member in the axial direction, and there is a possibility that sufficient strength cannot be secured with resin. On the other hand, the metal rod 74 is integrated with the metal plate member 155 and then insert-molded to ensure the strength of the rod 74, and the plate member 155 also secures the collapse of the metal rod 74 as a whole. As a result, the durability can be improved.
In the fourth embodiment, since the central axis DR of the rod 74 and the central axis DP of the piston main body 153 are arranged on the same axis, when the piston main body 153 rotates, the rod 74 also rotates integrally. Since the plate member 155 and the plate member 155 are integrated, uneven wear is not caused. Further, the falling force does not act on the rod 74 due to the rotational force, and the durability of the rod 74 is not affected.

As described above, the following operational effects can be obtained in the fourth embodiment.
(9) The plate member 155 and the rod 74 are integrally formed. Therefore, it is not necessary to consider the wear associated with the contact, and the durability can be improved. Moreover, it can ensure by the plate member 155, ensuring the intensity | strength of the rod 74, and can improve the durability as a whole.
Here, FIG. 9 is an enlarged partial sectional view showing the configuration of the reservoir of another embodiment. The basic configuration is the same as that of the fourth embodiment. In the fourth embodiment, the rod 74 and the plate member 155 are separated from each other and are integrally formed by press-fitting them. However, the rod member 300 in which the rod portion 302 and the plate portion 301 are integrally formed in advance is manufactured. The same effect can be obtained by insert molding the rod member 300 in the same manner as in the fourth embodiment.

The technical ideas that can be grasped from the above embodiments will be listed below.
(10) A resin piston main body formed in a bottomed hole formed in a housing having an oil passage inside and communicating with the oil passage, and strokes in the bottomed hole during antilock brake control;
A plate member that is provided on the crown surface of the piston body and has higher wear resistance than the resin;
A first elastic member that urges the piston body toward the bottom of the bottomed hole;
A valve body disposed in the oil passage;
A rod that is disposed between the seat portion with which the valve body abuts, the plate member, and the valve body, and separates the valve body from the seat portion;
A pressure regulating valve comprising: a second elastic member having an elastic force weaker than that of the first elastic member that is in contact with the valve body at one end side and biases in the direction of the seat portion;
A brake device comprising:
Therefore, even if it is a case where it is a resin-made piston main body in order to achieve weight reduction and cost reduction, the abrasion resistance with respect to the rod of a crown surface can be improved.
(11) In the brake device according to (10) above,
The brake device according to claim 1, wherein the plate member is integrally formed with the piston body.
Therefore, it can manufacture simultaneously with resin molding of a piston main body, and can improve productivity.

(12) In the brake device according to (10) above,
A coil spring which is the first elastic member;
The piston body is a bottomed cylindrical member having a bottom,
The brake device according to claim 1, wherein the coil spring supports the bottom portion, and the diameter of the plate member is larger than the outer diameter of the coil spring.
Therefore, only the compressive force acts on the crown surface, and a decrease in durability can be suppressed.
(13) In the brake device according to (12) above,
The brake device, wherein the plate member and the rod are integrally formed.
Therefore, it is not necessary to consider the wear associated with the contact, and the durability can be improved.
(14) In the brake device according to (10) above,
The brake device according to claim 1, wherein a maximum diameter of the plate member is formed larger than a maximum stroke amount of the piston body.
Therefore, even when the plate member is peeled off from the piston body, a stable operation can be maintained without hindering the stroke of the piston body.
(15) In the brake device according to (10) above,
The piston body is rotatably disposed in the bottomed hole,
The brake device according to claim 1, wherein the rod is disposed offset from a rotation center of the piston.
That is, the rod and the plate member do not always come into contact with each other at the same position, but the piston main body makes contact with the piston body while appropriately rotating and changing the contact position, so that the durability of the plate member can be improved.

(16) In the brake device according to (10) above,
An annular groove formed on the outer periphery of the piston body;
An annular seal member mounted in the annular groove, sealing between the inner peripheral surface of the bottomed hole and partitioning the inside of the bottomed hole into a hydraulic chamber and an air chamber;
A brake device comprising a weld line in a region of an air chamber of the piston body.
That is, the piston body is configured so that the weld line is formed at a position where accuracy related to liquid tightness is not required, in other words, the weld line is not formed at a location where accuracy is required. The required accuracy can be ensured while improving productivity.

(17) a resin piston main body assembled in a bottomed hole communicating with the oil passage in a housing in which an oil passage is formed;
A metal plate member integrally provided on the crown surface of the piston body;
A valve body disposed in the oil passage;
A metal rod disposed between the seat portion with which the valve body abuts, the plate member and the valve body, and separating the valve body from the seat portion;
A coil spring that biases the piston body toward the bottom of the bottomed hole;
It comprises an elastic member having an elastic force weaker than the urging force of the coil spring that has one end abutted against the valve body and urges it in the direction of the seat portion, and separates the valve body from the seat portion when not operating. A pressure regulating valve configured in
Having a reservoir function capable of storing the brake fluid that has flowed out of the wheel cylinder of the vehicle during anti-lock brake control in the bottomed hole by the stroke of the piston body;
The said piston main body is a bottomed cylindrical member which has a bottom part, The said bottom part is supported by the said coil spring, The diameter of the said plate member is larger than the outer diameter of the said coil spring, The brake device characterized by the above-mentioned.
Therefore, even if it is a case where it is a resin-made piston main body in order to achieve weight reduction and cost reduction, the abrasion resistance with respect to the rod of a crown surface can be improved. Further, only the compressive force acts on the crown surface, and a decrease in durability can be suppressed.

(18) In the brake device according to (17),
The brake device according to claim 1, wherein the metal plate member is made of stainless steel.
Therefore, corrosion resistance can be improved while ensuring the required strength.
(19) In the brake device according to (18) above,
The brake device according to claim 1, wherein the plate member has a disk shape and a maximum diameter is larger than a maximum stroke amount of the piston body.
Therefore, even when the plate member is peeled off from the piston body, a stable operation can be maintained without hindering the stroke of the piston body.
(20) In the brake device according to (19),
The piston body is rotatably disposed in the bottomed hole,
The brake device according to claim 1, wherein the rod is disposed offset from a rotation center of the piston body.
That is, the rod and the plate member do not always come into contact with each other at the same position, but the piston main body makes contact with the piston body while appropriately rotating and changing the contact position, so that the durability of the plate member can be improved.

7 Pressure regulating valve 10 Liquid path 10a Liquid path 10b Liquid path 11 Liquid path 13 Liquid path 15 Reservoir 31 Housing 31a Bottomed hole 31b Small diameter cylindrical portion 31c Pressure regulating valve housing hole 32 Brake hydraulic pressure control device 71 Seat member 71a Seat portion 72 Ball Member 73 Pressure adjusting valve return spring 74 Rod 75 Filter member 151 Retainer member 152 Coil spring 153 Piston body 153a Cylindrical inner periphery 153a1 Bottom 153b Weld line forming portion 153e Annular groove 153g Claw portion 153h Piston surface 153j Crown surface 153m Deposition film 154 Annular seal Member 155 Plate member 155c Locate hole 160 Plate member 300 Rod member 301 Plate portion 302 Rod portion
M / C Master cylinder P Pump unit
W / C wheel cylinder

Claims (5)

A housing having an oil passage formed therein;
A piston body assembled in a bottomed hole formed in the housing and communicating with the oil passage;
A first elastic member that urges the piston body toward the bottom of the bottomed hole;
A rod disposed in the oil passage, disposed between a valve body, a seat portion with which the valve body abuts, a crown surface of the piston body, and the valve body, and separates the valve body from the seat portion;
A pressure regulating valve comprising: a second elastic member having an elastic force weaker than that of the first elastic member that is in contact with the valve body at one end side and biases in the direction of the seat portion;
During anti-lock brake control, the piston body has a reservoir function capable of storing the brake fluid that has flowed out of the wheel cylinder in the bottomed hole by the stroke of the piston body;
A brake characterized in that the piston body is molded with resin, a hard body harder than the resin is fixed to the crown surface of the piston body, and the piston body and the rod are brought into contact with each other through the hard body. apparatus. The brake device according to claim 1, wherein
The brake device, wherein the hard body is a plate member and is integrally formed with the piston body. The brake device according to claim 2,
The plate member has a disk shape,
The first elastic member is a coil spring;
The piston body is a member formed in a bottomed cylindrical shape having a bottom,
The brake device according to claim 1, wherein the coil spring supports the bottom portion, and the diameter of the plate member is larger than the outer diameter of the coil spring. The brake device according to claim 3,
The brake device according to claim 1, wherein a maximum diameter of the plate member is larger than a maximum stroke amount of the piston body. The brake device according to claim 4,
The piston body is rotatably disposed in the bottomed hole,
The brake device according to claim 1, wherein the rod is disposed offset from a rotation center of the piston body.

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