JP2000185637A - Reservoir - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cutting precision by a drill on an inner surface of a cast hole in a reservoir in which a reservoir piston is slidably engaged with a reservoir hole having a bottom formed by a cutting at least part of the inner surface of the cast hole. SOLUTION: A reservoir hole 26 is composed of a cut hole part 26a formed by cutting an inner surface of a cast hole 62 by a cutting tool, and a closing end wall 26a for closing an inner end of the cut hole part 26a, the closing end wall 26a comprises a recessed part 26b1 left in a cast state of the cast hole 62 to let a tip central part of a cutting tool escape, and a circular flat surface 26b2 cut by a tip outer circumferential part of the cutting part to surround the recessed part 26b1, and at an end surface of a reservoir piston 28 facing the closing end wall 26b, a protrusion 28a which can get in contact with the flat surface 26b2 is protruded in such form and disposition as to avoid closing the recessed part 26b1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reservoir,
In particular, the present invention relates to an improvement in a reservoir suitably used for a brake fluid pressure control device of a vehicle such as a passenger vehicle or a motorcycle.

[0002]

2. Description of the Related Art Conventionally, such a reservoir is already known, for example, from Japanese Patent Application Laid-Open No. 8-261201, etc., in which a closed bottomed reservoir hole provided in a housing to be molded is provided with a closed end of the reservoir hole. A reservoir piston that forms a reservoir chamber therebetween is slidably fitted while being spring-biased to a side that reduces the volume of the reservoir chamber.

[0003]

By the way, the bottomed reservoir hole provided in the housing is fitted into the inner surface of the bottomed cast hole formed in the housing at the time of casting to slidably fit the reservoir piston. It is formed by cutting with a cutting tool such as a reamer to obtain it.

However, in the above-described conventional apparatus, cutting is performed by the reamer until the center of the tip of the reamer contacts the closed end of the cast hole, and the center of the tip of the reamer contacts the closed end of the cast hole. And the cutting resistance at the time of cutting the central portion of the closed end face with the tip of the reamer may reduce the cutting accuracy of the inner surface of the cast hole.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a reservoir capable of improving the cutting accuracy of an inner surface of a cast hole by a cutting tool.

[0006]

In order to achieve the above object, an invention according to claim 1 is characterized in that at least a part of an inner surface of a bottomed cast hole formed in a housing to be formed by casting. A reservoir piston is formed in a bottomed reservoir hole formed by cutting a cutting tool, a reservoir chamber is formed between the reservoir hole and a closed end of the reservoir hole, and a spring is biased to a side that reduces the volume of the reservoir chamber. In a reservoir, which is slidably fitted and has a passage provided in the housing and extending upward from the reservoir chamber, the reservoir hole is formed by cutting an inner surface of a cast hole with the cutting tool. And a closed end wall that closes the inner end of the cutting hole, and the closed end wall is left in the as-cast state of the as-cast hole, and a concave portion that escapes the center of the tip of the cutting tool, The cutting machine And a ring-shaped flat surface that is cut at the outer periphery of the tip of the reservoir piston and surrounds the concave portion. On the end surface of the reservoir piston that faces the closed end wall, a protrusion that can contact the flat surface has the concave portion. It is characterized by being protruded in a shape and an arrangement to avoid closing.

According to the structure of the first aspect of the present invention, when forming the reservoir hole by cutting at least a part of the inner surface of the cast hole with the cutting tool, the tip of the cutting tool is cast. The hole is released in the recess at the closed end of the hole, thereby avoiding an increase in cutting resistance due to the center of the tip of the cutting tool contacting the center of the closed end of the cast hole, and improving the cutting accuracy by the cutting tool. be able to. In addition, since the projection does not close the recess, it is possible to prevent the air from remaining in the recess when the reservoir is filled with the working fluid. In addition, since the projection provided on the reservoir piston abuts on the flat surface of the closed end wall, a loss load occurs during the stroke of the reservoir piston due to the metal contact between the contact surfaces of the reservoir piston and the closed end wall. Thus, the responsiveness of the reservoir piston can be improved.

[0008] The invention according to claim 2 provides the above-mentioned claim 1.
In addition to the configuration of the invention described, the plurality of protrusions formed in a circular cross section are provided on the reservoir piston at intervals in a circumferential direction of the circular recess,
According to such a configuration, it is possible to prevent the protrusion from obstructing the air bleeding in the concave portion, and it is possible to more effectively bleed air from the concave portion.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

1 to 10 show an embodiment of the present invention. FIG. 1 is a brake hydraulic circuit diagram of a brake device for a passenger vehicle, FIG. 2 is a side view of a brake hydraulic pressure control device, and FIG.
4 is a view as viewed from the direction of the arrow 3 in FIG. 2, FIG. 4 is a view as viewed from the direction of the arrow 4 in FIG. 2, and FIG.
6 is a sectional view taken along line 5-5, FIG. 6 is a sectional view taken along line 6-6 in FIG.
8 is a sectional view taken along the line 7-7 in FIG. 6, FIG. 8 is an enlarged sectional view of the reservoir, FIG. 9 is a sectional view showing a cutting state of the cast hole by a reamer, and FIG. 10 is a sectional view taken along the line 10-10 in FIG. is there.

[0011] First, in FIG. 1, a master cylinder M of a tandem type, equipped with a vehicle operator first and second output ports 1 ₁ generates a brake fluid pressure corresponding to the depression force applied to the brake pedal P is 1 ₂ And a left front wheel brake B ₁ , a right rear wheel brake B ₂ , a right front wheel brake B _{3, a} left rear wheel brake B _4, and the first and second output ports 11 ₁ and _12. First individually connected to
And brake fluid pressure control device 3 is provided between the second output hydraulic pressure line 2 _1, 2 _2, the brake fluid pressure control device 3 and the right, between the wheels for the left rear wheel brake B _2, B _4, First and second proportional pressure reducing valves 4 ₁ and 4 ₂ are provided respectively.

[0012] Brake fluid pressure control device 3, the individually corresponding to the left front wheel brake B _1, a right rear wheel brake B _2, the right front wheel brake B ₃ and the left rear wheel brake B ₄ First, second, third and fourth normally open solenoid valves 5
₁ and 5 _4, first to be connected in parallel to the normally open electromagnetic valves 5 ₁ to 5 _4, second, third and fourth check valves 7
And _{1-7 4,} wherein the first individually corresponding to each wheel brake B ₁ .about.B _4, second, third and fourth normally closed electromagnetic valves 6 ₁ -
6 _4, first and second reservoirs _81, 82 which first and second output fluid pressure line 2 _1, 2 ₂ respectively correspond individually
₂ and the first and second reservoirs 8 ₁ and 8 ₂
Plunger-type first and second pumps 11 ₁ and 11 ₂ connected via respective ₁ and 10 ₂ , and both pumps 11
_1, 11 ₂ and the common one electric motor 12 for driving the discharge valve 13 _1, 1 to ₂ first and second pumps 11 _1, 11
3 ₂ and the first and second dampers 14 _1, 14 ₂ are connected via respective first and second output fluid pressure line 2 _1, 2 ₂ and the first and second dampers 14 _1, 14 ₂ and First and second orifices 15 respectively interposed between
_1, comprising 15 and _2, the normally open electromagnetic valve 5 ₁ to 5 _4, and an electronic control unit 16 for controlling the operation of the normally closed solenoid valve ₆₁ through ₄ and the electric motor 12.

First normally open solenoid valve 5₁Is the first output hydraulic path
2₁And left front wheel brake B ₁Provided between the
2 normally open solenoid valve 5_TwoIs the first output hydraulic pressure path 2₁And the first
Proportional pressure reducing valve 4₁A third normally-open solenoid valve 5
_ThreeIs the second output hydraulic path 2_TwoAnd right front wheel brake
B_ThreeA fourth normally-open solenoid valve 5_FourIs the second output
Hydraulic passage 2_TwoAnd the second proportional pressure reducing valve 4_TwoIt is provided between them.

[0014] The first to fourth check valves 7 ₁ to 7 _4,
From the corresponding wheel brakes B _{1 to} B ₄ to master cylinder M
So as to permit a flow of brake fluid to be connected in parallel to the normally open electromagnetic valves 5 ₁ to 5 _4.

First normally closed solenoid valve 6₁Is the left front wheel
Rake B₁And the first reservoir 8₁Between the second
Normally closed solenoid valve 6_TwoIs the first proportional pressure reducing valve 4₁And the first
Observer 8₁A third normally closed solenoid valve 6_ThreeIs right
Front wheel brake B_ThreeAnd the second reservoir 8_TwoSet between
The fourth normally closed solenoid valve 6_FourIs the second proportional pressure reducing valve 4 _Two
And the second reservoir 8_TwoIt is provided between them.

By the way, the first normally open electromagnetic valve 5 ₁ and the first normally closed solenoid valve ₆₁ constitute a first control valve means V ₁ in cooperation, the second normally open electromagnetic valve 5 ₂ and Second normally closed solenoid valve 6
₂ constitutes a second control valve means V ₂ in cooperation, the third normally open electromagnetic valve 5 ₃ and a third normally closed electromagnetic valve 6 ₃ 3 cooperates
Constitute a control valve unit V _3, a fourth normally open electromagnetic valve 5 ₄ and the fourth normally closed electromagnetic valve 6 ₄ constitutes the fourth control valve unit V ₄ in cooperation.

Such control valve means V₁~ V_FourIs each car
At the time of normal braking where the wheel may not lock,
The electronic control unit 16 allows the master cylinder M and
Wheel brake B₁~ B_FourBetween the wheels
B₁~ B_FourAnd reservoir 8₁, 8_TwoShut off
State controlled. That is, each normally open solenoid valve 5₁~ 5 _Four
Is demagnetized and opened, and each normally closed solenoid valve 6₁
~ 6_FourIs demagnetized and the valve is closed, and the master cylinder M
1 output port 1₁The brake fluid pressure output from the
Normally open solenoid valve 5₁Through the front left wheel brake B₁To
And the second normally-open solenoid valve 5_TwoAnd first ratio
Example pressure reducing valve 4₁Via the rear right wheel brake B_TwoActs on
I do. Also, the second output port 1 of the master cylinder M_TwoFrom
The output brake fluid pressure is the third normally open solenoid valve 5_ThreeThrough
And right front wheel brake B_ThreeActs on the
4 normally open solenoid valve 5_FourAnd the second proportional pressure reducing valve 4_TwoThrough
Wheel brake B for left rear wheel_FourAct on.

When the wheel is about to enter the locked state during the braking, the control valve means corresponding to the wheel about to enter the locked state among the control valve means V _{1 to} V ₄ is controlled by electronic control. the unit 16 is controlled to a state of communication between the wheel brake B ₁ .about.B ₄ and the reservoir 8 _1, 8 ₂ with interrupting the connection between the master cylinder M and the wheel brakes B ₁ .about.B _4. That normally open electromagnetic valve corresponding to the first to fourth wheel is likely to become locked out of the normally open electromagnetic valve 5 ₁ to 5 ₄ are energized, while being closed,
Normally closed solenoid valve corresponding to the first to fourth the wheel of the normally closed solenoid valve ₆₁ through ₄ are energized, is opened. This allows
Some of the brake fluid pressure of the wheel which is likely to become locked is absorbed in the ₂ first reservoir 8 ₁ or the second reservoir 8, the brake fluid pressure of the wheel which is likely to become locked is reduced become.

When the brake fluid pressure is kept constant, each of the control valve means V _{1 to} V ₄ is controlled by the electronic control unit 16.
By, it is controlled to a state of blocking the wheel brake B ₁ .about.B ₄ from the master cylinder M and the reservoir 8 _1, 8 _2. That normally open electromagnetic valve 5 ₁ to 5 ₄ are energized, while being closed, the normally closed solenoid valve ₆₁ through ₄ are demagnetized, will be closed. When further increasing the brake fluid pressure,
The normally open electromagnetic valve 5 ₁ to 5 ₄ are demagnetized, an open state, the normally closed solenoid valve ₆₁ through ₄ need be demagnetized, a closed state.

By controlling the control valve means V _{1 to} V ₄ by the electronic control unit 16 in this manner, braking can be efficiently performed without locking the wheels.

Incidentally, the above-described anti-lock blur
During the brake control, the electric motor 12 is controlled by the electronic control unit 16.
Activated by For the operation of the electric motor 12,
Accordingly, the first and second pumps 11₁, 11_TwoIs driven
Therefore, the first and second reservoirs 8₁, 8_TwoAbsorbed into
The brake fluid is supplied to the first and second pumps 11.₁, 11 _Two
And then the first and second dampers 14₁, 14
_TwoAnd the first and second orifices 15₁, 1
5_TwoThrough the first and second output hydraulic lines 2₁, 2 _TwoReflux
Is done. Due to such a reflux of the brake fluid, the first and second brake fluids are generated.
And second reservoir 8₁, 8_TwoDue to the absorption of brake fluid
It is possible to prevent an increase in the amount of depression of the brake pedal P.
You. Moreover, the first and second pumps 11₁, 11_TwoDischarge
The pressure pulsation is caused by the first and second dampers 14.₁, 14_Two,
And first and second orifices 15₁, 15_TwoCollaboration
Is absorbed by the
The operation feeling of the dull P is not hindered.

In FIG. 2 to FIG.
The device 3 is made of, for example, a block of aluminum alloy or the like.
A housing 20 that is cast into
The housing 20 is provided with first to fourth normally open solenoid valves 5.₁~
5_Four, Those normally open solenoid valves 5₁~ 5_FourAnd control valve means V
₁~ V_FourFirst to fourth normally closed solenoid valves 6₁~
6 _Four, The first to fourth check valves 7₁~ 7_Four, The first and
Second reservoir 8₁, 8_Two, First and second dampers 1
4₁, 14_Two, First and second orifices 15₁, 15
_TwoAnd the first and second pumps 11₁, 11_TwoIs set
Be killed. A synthetic tree is provided on one surface 20a of the housing 20.
A cover 21 made of oil is attached, and is opposite to the cover 21.
On the other side 20b of the housing 20
The data case 22 is attached.

Referring to FIG. 5 to FIG. 7 together, first to fourth
Normally open solenoid valve 5₁~ 5_FourIs connected to the solenoid 5 by the valve 5a.
b are connected to each other.
0 so that the housing 20
The four mounting holes 23 provided in the upper part of the
Are accommodated, and each solenoid portion 5b.
It protrudes from one surface 20a. Also, first to fourth normally closed solenoid valves
6₁~ 6_FourHas a solenoid 6b on the valve 6a
The one surface 20 of the housing 20
a on the upper part of the housing 20 so as to open to
Each of the valve portions 6a is accommodated in four mounting holes 24,
Each solenoid part 6b ... is one surface 20a of the housing 20?
Protrude. Moreover, the mounting holes 23 are arranged side by side in a horizontal direction.
Mounting holes 24...
The housings are arranged side by side below these mounting holes 23.
20, the first to fourth normally-open solenoid valves 5₁~
5 _FourAnd first to fourth normally closed solenoid valves 6₁~ 6_FourIs up and down
They will be mounted on the housing 20 in parallel.

The first reservoir 8 _1, the control valve means V _1, V
₂ is provided at the lower part of the housing 20 at a position corresponding to ₂ ,
₂ second reservoir 8 is disposed in the lower portion of the housing 20 at a position corresponding to the control valve unit V _3, V _4.

In FIG. 8, both reservoirs 8 ₁ and 8 ₂ are
A reservoir chamber 27 is formed between a bottomed reservoir hole 26 provided in the housing 20 so as to open on one surface 20 a of the housing 20 and a closed end of the reservoir hole 26, and can slide in the reservoir hole 26. A cylindrical reservoir piston 28 having a bottom, a receiving member 29 fitted to the open end of the reservoir hole 26, and a reservoir 29 for preventing the receiving member 29 from coming out of the reservoir hole 26. It comprises a retaining ring 30 attached to the opening edge of the hole 26, and a reservoir spring 31 contracted between the receiving member 29 and the reservoir piston 28.

In FIG. 9, the reservoir hole 26 is formed by cutting at least a part of an inner surface of a bottomed hole 62 formed at the time of casting in the housing 20 to be cast by a reamer 63 as a cutting tool. Consisting of
It comprises a cut hole 26a formed by cutting the inner surface of the cast hole 62 with the reamer 63, and a closed end wall 26b closing the inner end of the cut hole 26a.

The cast hole 62 is provided with a cast pin (not shown).
Is formed in a tapered shape having a larger diameter toward the outer end opening side in order to facilitate the detachment. Also reamer 63
Has a step with a small diameter at the distal end side, and the cutting hole 26 a is also formed with a step according to the outer shape of the reamer 63.

The reservoir piston 28 is slidably fitted into the cutting hole 26a in the reservoir hole 26. The outer periphery of the reservoir piston 28 slides on the inner surface of the cutting hole 26a. Annular sealing member 6 in contact
5 is mounted.

The closed end wall 2 for closing the inner end of the reservoir hole 26
6b is a recess 26b ₁ that are left in the state punching cast of punching holes 62 cast, a ring-shaped flat surface 26b ₂ Metropolitan which is cut by the tip outer peripheral portion of the reamer 63 surrounding the recess 26b _1. Central tip portion 63a of the reamer 63 Thus to cutting a machining hole 26a and the flat surface 26b ₂ becomes to be released in the recess 26b _1, the central end portion 63a of the reamer 63 to the closed end wall 26b There is no contact.

Referring also to FIG. 10, for example, at three places on the end face of the reservoir piston 28 facing the closed end wall 26b, a flat surface 26 of the closed end wall 26b is provided.
b ₂ can be partially contacted, and the remaining
Projection 28a to face the 6b ₁ ... are projected. Moreover the projections 28a ... is one in contact with the flat surface 26b ₂ which is projected from the reservoir piston 28 in shape and arrangement to avoid blocking the recess 26b _1, in this embodiment, a circular cross section projections 28a ... is formed, is projected into the reservoir piston 28 at three positions equally spaced in the peripheral direction of the recess 26b ₁ is circular.

The housing 20 has a reservoir chamber 27.
It is provided with passages 64 extending upward from, the passage 64 is connected to the first and second pumps 11 _1, 11 _2.

The first damper 14 ₁ is provided with control valve means V ₁ , V
Disposed in the housing 20 at a position corresponding to between the _second and first reservoir 8 _1, the second damper 14 ₂ is the control valve unit V
_3, in V ₄ and a position corresponding to the second reservoir 8 between ₂ are disposed in the housing 20.

The dampers 14 ₁ and 14 ₂ are connected to the housing 2
0 so that the housing 20
And a piston 35 which is slidably fitted into a damper hole 33 having a bottom provided therein and forms a damper chamber 34 with the closed end of the damper hole 33, and is fitted into an open end of the damper hole 33. A receiving member 36, a retaining ring 37 attached to the opening edge of the damper hole 33 so as to prevent the receiving member 36 from coming out of the damper hole 33, and one or more members provided between the receiving member 36 and the piston 35. Multiple disc springs 38
, And both dampers 14 ₁ ,
14 ₂ of the damper chamber 34 ... the first and second pumps 1
11 ₁ and 11 ₂ .

The first and second pumps 11 ₁ and 11 ₂ are
First to fourth normally closed electromagnetic valve ₆₁ through _4, first and second
Between the reservoir 8 _1, 8 _2, which is disposed in the housing 20 has a coaxial actuating axes along the first to fourth arrangement direction of the normally closed solenoid valve ₆₁ through _4, Both pumps 1
1 _1, 11 ₂ plunger 40 ... are provided respectively, is arranged at a position spaced between each other. Also both pumps 1
1 _1, 11 _2, intake valve 10 _1, 10 ₂ and the discharge valve 13 _1, 13 ₂ are built respectively.

On the other hand, the motor case 22 of the electric motor 12
Is a cylindrical case body 22a having a bottom and the case body 2
And a lid 22b disposed so as to close the open end of the case 2a.
Are fastened to the other surface 20b of the housing 20 by a plurality of screw members 41. Output shaft 4 of the electric motor 12
2 penetrates the lid 22b rotatably, and the housing 20
Is extended to the inside of the concave portion 43 provided in the
b and a ball bearing 45 held at the inner end of the recess 43. In addition, an eccentric shaft portion 42a is provided on the output shaft 42 at an intermediate portion located between the bearings 44 and 45, and the first and second ball bearings 46 mounted on the outer periphery of the eccentric shaft portion 42a are provided. The pumps 11 ₁ , 11 ₂ are in contact with the tips of the plungers 40. Therefore, when the output shaft 42 is rotated by the operation of the electric motor 12, the ball bearing 46 is rotated via the eccentric shaft 42a.
The eccentric movement is given to each plunger 40.
Will be given a pump operation.

The cover 21, the first to fourth solenoid portion 5a of the normally open solenoid valves 5 ₁ to 5 ₄ ..., the first to
Fourth solenoid portion 6b in the normally closed solenoid valve ₆₁ through ₄
, And the first and second reservoirs 8 ₁ , 8 ₁ ,
The receiving member 29 ... and the first and second dampers 14 _1, 14 receiving member 36 ... accommodating chamber 48 for exposing the at ₂ in 8 ₂ so as to form between the housing 20 by a plurality of screw members 49 ... It is fastened to one surface 20a of the housing 20. Thus, the housing 2 of the cover 21
An endless seal member 71 that resiliently contacts the one surface 20a of the housing 20 is attached to the 0-side edge.

[0037] the cover 21 of the intermediate portion, of the first through fourth normally open electromagnetic valve 5 ₁ to 5 each solenoid of ₄ 5b ... and the first through fourth normally closed electromagnetic valve ₆₁ through ₄ Each solenoid 6b
Are provided, and a support portion 50 is provided for fitting and supporting the support portion 5.
A plurality of openings 52 are formed in the housing 0 so that the storage section 48 is not partitioned by the support section 50.

The electronic control unit 16 is configured by mounting a semiconductor chip 54 and the like on a substrate 53 on which an electric circuit is printed, and the substrate 53 is mounted on the support portion 50 on the side of the cover 21 opposite to the housing 20. Will be concluded. Moreover, a plurality of bus bars 51 made of conductive metal are provided on the support portion 50.
… Are buried, and these busbars 51…
Each solenoid unit of the first to fourth normally open electromagnetic valve 5 ₁ to 5 ₄ 5
b ... and the first to fourth respective solenoid portions 6b of the normally closed solenoid valve ₆₁ through ₄ ... is connected to the electronic control unit 16.

The cover 21 is integrally formed with a protruding portion 21a protruding laterally from the housing 20, and a male connector 55 is provided on the protruding portion 21a.

The cover-side connector 55 is
And a plurality of connector terminals 57 which are housed and supported in the connector housing 56 and are formed integrally with the projecting portion 21a. Are connected to the solenoid units 5b, 6b via the electronic control unit 16 and the bus bars 51, respectively.
6 and an electric motor 12 via a conductor (not shown).

A connector housing 77 of an external conductor side connector 76 provided commonly at the ends of a plurality of external conductors 75 is detachably connected to the cover side connector 55 connected to the cover 21. The connector terminals (not shown) provided in the connector housing 77 so as to be individually connected to the conductors 75, 75.
Are fitted and connected to the connector terminals 57.

Referring to FIGS. 2 and 3, the vehicle body frame 88 includes a support plate 8 facing the lower surface of the housing 20.
9a and a pair of support plate portions 89 which are provided at right angles to both ends of the support plate portion 89a and face both side surfaces of the housing 20.
b, 89b are fixed.

On the other hand, mounting projections 102, 102 are integrally formed on both sides of the upper portion of the housing 20, and the mounting projections 102, 102 are mounted on the upper portions of the support plates 89b, 89b of the bracket 89 by mounting means. It is attached via 91,91.

The mounting means 91 has a mounting bolt 103 having an axis extending substantially horizontally and supported on the supporting plate 89b, and a cylindrical mounting rubber 104 into which a part of the mounting bolt 103 is fitted. The mounting protrusion 102 has the mount rubber 104
Is provided with a mounting hole 105 having a bottom.

The mounting bolt 103 is connected to the screw shaft 103
a, a fitting shaft portion 103b coaxially and integrally connected to the screw shaft portion 103a, and a flange portion 10 extending radially outward from a continuous portion of the screw shaft portion 103a and the fitting shaft portion 103b.
3c. On the other hand, the support plate 89
A slit 106 opening upward is provided at the upper part of b, and a portion of the screw shaft portion 103a near the flange portion 103c is inserted into the slit 106 from above. A nut 107 is screwed into the screw shaft portion 103a, and the support plate portion 89b is sandwiched between the nut 107 and the flange portion 103c, so that the mount bolt 103 is fixed to the support plate portion 89b. Will be supported.

The lower part of the housing 20 is mounted on a support plate 89a of a bracket 89 via mounting means 90.
A mount rubber (not shown) fitted to a lower part of the housing 20 is fixed to the support plate 89a.

Next, the operation of this embodiment will be described. The bottomed reservoir holes 26 in the reservoirs 8 ₁ and 8 ₂ will be described.
Is formed by cutting at least a part of the inner surface of a cast hole 62 formed simultaneously with the casting of the housing 20 by a reamer 63, and is formed by cutting the inner surface of the cast hole 62 by the reamer 63. Cut hole 26a
And a closed end wall 26 for closing the inner end of the cut hole 26a.
b, and the closed end wall 26b is left in the cast-out state of the cast-out hole 62, and the tip end central portion 6 of the reamer 63 is formed.
The recess 26b ₁ to escape 3a, a ring-shaped flat surface 26b ₂ Metropolitan which is cut by the tip outer peripheral portion of the reamer 63 surrounding the recess 26b _1.

Therefore, the inner surface of the cast hole 62 is cut by the reamer 63 to form the cut hole 26a and the flat surface 2a.
When forming 6b ₂ , the central portion 63a of the tip of the reamer 63
But will be released in the recess 26b ₁ in the closed end of the punching holes 62 cast, it is possible to improve the cutting accuracy of the reamer 63 to avoid an increase in accompanying cutting resistance in the cutting of the closed end.

Moreover, the closed end wall 2 of the reservoir piston 28
The end surface facing the 6b, possible projections 28a contact the flat surface 26b ₂ ... it is projected. For this reason, the reservoir piston 2 is moved in the direction of reducing the volume of the reservoir chamber 27 to the maximum.
8 when the mobile has, since projections 28a ... which reservoir piston 28 is provided comes into contact with the flat surface 26b ₂ at the closed end wall 26b of the reservoir hole 26, the reservoir piston 2
A loss load is prevented from occurring during a stroke of the reservoir piston 28 due to a metal contact between contact surfaces of the reservoir piston 28 and the closed end wall 26b.
Responsiveness can be improved.

[0050] Moreover, since the projections 28a ... is projected to the reservoir piston 28 in shape and arrangement to avoid plugging the recess 26b _1, air in the recess 26b ₁ at the time of filling of the working fluid into the reservoir chamber 27 A passage 64 extending upward from the reservoir chamber 27 to prevent the accumulation
It can be carried out air bleeding from the recess 26b ₁ smoothly.

A plurality of protrusions 28 having a circular cross section are provided.
are the circular concave portions 26b₁Spaced in the circumferential direction
The projection 2 is provided on the reservoir piston 28 so that the recess 2
6b ₁... that the protrusions 28a ...
Evacuated, recess 26b₁Bleed air more effectively
I can.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the present invention described in the appended claims. It is possible to do.

[0053]

As described above, according to the first aspect of the invention, when cutting the inner surface of the cast hole with a cutting tool, it is possible to avoid an increase in cutting resistance and improve the cutting accuracy. Thus, the responsiveness of the reservoir piston can be improved, and air can be prevented from remaining in the recess when the reservoir is filled with the working fluid.

According to the second aspect of the present invention, it is possible to prevent the protrusion from obstructing air bleeding in the concave portion, and to more effectively bleed air from the concave portion.

[Brief description of the drawings]

FIG. 1 is a brake hydraulic circuit diagram of a brake device for a passenger vehicle.

FIG. 2 is a side view of the brake fluid pressure control device.

FIG. 3 is a view as viewed in the direction of arrow 3 in FIG. 2;

FIG. 4 is a view taken in the direction of arrow 4 in FIG. 2;

FIG. 5 is a sectional view taken along line 5-5 in FIG. 4;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 4;

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6;

FIG. 8 is an enlarged sectional view of a reservoir.

FIG. 9 is a cross-sectional view showing a state in which a cast hole is cut by a reamer.

FIG. 10 is a sectional view taken along line 10-10 of FIG. 8;

[Description of Reference Numerals] _81, 82 ... reservoir 20 ... housing 26 ... reservoir hole 26a ... cutting holes 26b ... closed end wall 26b ₁ ... recess 26b ₂ · ·・ Flat surface 27 ・ ・ ・ Reservoir chamber 28 ・ ・ ・ Reservoir piston 28a ・ ・ ・ Protrusion 62 ・ ・ ・ Cast hole 63 ・ ・ ・ Reamer as cutting tool 63a ・ ・ ・ Central portion of tip of reamer 64 ・ ・ ・aisle

Claims (2)

[Claims] At least a part of an inner surface of a cast hole (62) having a bottom formed in a housing (20) to be cast at the time of casting is formed by cutting a cutting tool (63). Into the reservoir hole (26).
A reservoir piston (28) which forms a reservoir chamber (27) with the closed end of 6) and is spring-biased to the side of reducing the volume of the reservoir chamber (27) is slidably fitted, A passage (6) extending upward from the reservoir chamber (27)
4) A reservoir provided in the housing (20), wherein the reservoir hole (26) is a cast-out hole (62).
Are formed by a cutting hole (26a) formed by cutting the inner surface of the cutting tool (63) with the cutting tool (63), and a closed end wall (26b) for closing the inner end of the cutting hole (26a). (26b) is left in the cast-out state of the cast-out hole (62), and the tip center portion (63) of the cutting tool (63) is left.
a) and a recess (26b ₁ ) for releasing the cutting tool (6).
Is cut at the tip outer peripheral portion of 3) become from a ring-shaped flat surface surrounding the concave portion (26b ₁₎ (26b _2), the end face opposite the closed end wall (26b) of the reservoir piston (28) The reservoir is characterized in that a projection (28a) that can contact the flat surface (26b ₂ ) is formed in a shape and an arrangement to avoid blocking the recess (26b ₁ ). 2. A plurality of protrusions (28a) having a circular cross section are provided on the reservoir piston (28) at intervals in a circumferential direction of the circular recess (26b ₁ ). The reservoir of claim 1, wherein: