JP2000272500A - Hydraulic generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a push rod and pedals in a crew compartment from returning to a driver side with the low cost without changing a structure of a car body and the like in a case where the external force acts on a hydraulic generator from the front of the car body by forming a recessed groove on an inner part of an engagement hole of a rear cylinder of a master piston. SOLUTION: A hydraulic generator 6 is projected on an engine room 1 side of a dash panel 3, and a valve housing 4b of a booster 4, a push rod 7 and an operation pedal 8 are arranged in a crew compartment 2. An engagement hole 50b is formed on a rear cylinder 50a of a master piston 50 inserted into a cylinder hole 5d of a hydraulic master cylinder 5. A shaft of small diameter 19b of an output rod 19 is inserted into the engagement hole 50b. A spiral recessed groove 50e is engraved on the engagement hole 50b over approximately 2/3 depth from a rear end surface 50d. The rear cylinder 50a is broken at a fragile part of the recessed groove 50e when the master piston 50 is inclined from a central shaft CL with the master cylinder 5 by the excess external force from the front of the car body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pressure generating device for a vehicle comprising two actuators, a booster for hydraulically operating a brake and a clutch of an automobile and a hydraulic pressure master cylinder. The present invention relates to a vehicle hydraulic pressure generating device that minimizes the physical influence on a passenger compartment when an external force such as a collision load acts from a front portion.

[0002]

2. Description of the Related Art A conventional general hydraulic pressure generating device used for hydraulically operating a brake or a clutch of an automobile is disclosed, for example, in Japanese Patent Application Laid-Open No. 7-4415. This hydraulic pressure generating device includes a booster protruding toward the front of the vehicle body from a side of the engine room of a dash panel that separates an engine room and an occupant from the front of the vehicle body, and a fluid connected to the vehicle body front of the booster. A push rod at the rear of the booster protrudes from the dash panel into the passenger compartment, and a brake pedal or a clutch pedal is connected to the rear end.

[0003] Inside the booster shell of the booster, a rear cylinder of a master piston inserted into a cylinder hole of a hydraulic master cylinder is arranged so as to protrude, and an output rod of the booster and a valve body are serially arranged in the longitudinal direction of the vehicle body on the rear side. The small diameter shaft portion of the output rod is inserted into the engagement hole inside the rear cylinder, and the tip of the small diameter shaft portion is brought into contact with the bottom wall of the engagement hole,
The pedal depression force transmitted to the booster is further transmitted to the hydraulic master cylinder.

[0004]

In such a configuration, when an external force such as an impact load acts on the front portion of the vehicle and the external force reaches the hydraulic master cylinder on the front side of the vehicle body, , The hydraulic master cylinder is pushed in the direction of the booster,
The master piston pushes the push rod back toward the passenger compartment via the output rod and the valve body, and the push rods and pedals in the passenger compartment may hit the driver's legs and the like.

[0005] As a countermeasure, it is conceivable to take measures to prevent the influence of the external force from reaching the passenger compartment as much as possible by tilting the hydraulic master cylinder or the booster which has been subjected to the external force from the front part of the vehicle body toward the vehicle body side. In this case, since the body structure is changed for mounting the hydraulic pressure generating device and special processing is required for the hydraulic pressure master cylinder and the booster, the number of manufacturing steps and the number of assembling steps are increased, and the manufacturing cost is increased. Also has the disadvantage of leading to

[0006] The present invention has been made in view of such circumstances, and an object of the present invention is to provide a push rod in an occupant compartment when an external force acts on the hydraulic pressure generating device from the front of the vehicle body. It is an object of the present invention to provide an inexpensive vehicle hydraulic pressure generating device which does not need to change the configuration of a hydraulic master cylinder or a booster or a vehicle body structure, while preventing as much as possible that pedals and the like are pushed back to a driver side. .

[0007]

According to the present invention, a booster for increasing a pedal depressing force is provided on a side of an engine room of a dash panel which separates an engine room at a front portion of a vehicle body and a passenger room following the engine room. A hydraulic master cylinder that converts the pedal depressing force increased by the booster to hydraulic pressure is connected to the front side of the vehicle body of the booster, and a rear part of a master piston inserted into a cylinder hole of the hydraulic master cylinder. The cylinder is arranged to protrude into the inside of the booster shell of the booster, and the small diameter shaft of the output rod of the booster is inserted into the engagement hole inside the rear cylinder, and the tip of the small diameter shaft is attached to the bottom wall of the engagement hole. In the vehicle hydraulic pressure generating device which comes into contact with the rear cylinder, an axial or circumferential groove is formed inside the engagement hole of the rear cylinder.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in more detail with reference to the drawings.

1 to 4 show a first embodiment of the present invention. FIG. 1 is a sectional view of a main part of a vehicle hydraulic pressure generating device, and FIG.
FIG. 3 is a front view of the entire hydraulic pressure generating device, FIG. 3 is an enlarged sectional view of a main part of the hydraulic pressure generating device for a vehicle, and FIG. 4 is an exploded perspective view of a main portion of the hydraulic pressure generating device for a vehicle. FIG. 5 is an enlarged sectional view of a main part showing a second embodiment of the present invention, FIG. 6 is an enlarged sectional view of a rear cylinder showing a third embodiment of the present invention, and FIG. 7 is a fourth embodiment of the present invention. FIG. 8 is an enlarged sectional view of a main part showing a fifth embodiment of the present invention.

A first embodiment shown in FIGS. 1 to 4 includes an engine room 1 on the front side of a vehicle body (left side in FIGS. 1 and 2),
A dash panel 3 separates an occupant compartment 2 following the rear side of the vehicle body of the engine compartment 1. The engine compartment 1 includes a booster 4 and a hydraulic master cylinder 5 on the side of the dash panel 3 in the engine compartment. A hydraulic pressure generating device 6 in which two hydraulic pressure generating actuators are connected in series is projected.

In the passenger compartment 2, a valve housing 4b of the booster 4, a push rod 7 and an operation pedal 8 are provided.
Then, the pedal depression force increased by the booster 4 is converted into a hydraulic pressure by the hydraulic master cylinder 5, and a brake or clutch (not shown) is hydraulically operated.

The booster 4 includes a large-diameter booster shell 4 a provided in the engine compartment 1 and a dash panel 3.
And a small-diameter cylindrical valve housing 4b projecting into the passenger compartment 2 through the vehicle body.
And the rear half 4d of the vehicle body. The rear side of the booster shell 4a is overlapped with the side of the engine compartment of the dash panel 3, and these are bolted to the dash panel 3, so that the booster 4 is It protrudes toward the front of the vehicle.

As the hydraulic master cylinder 5, a reservoir integrated type in which a reservoir 9 is directly connected to an upper portion of a cylinder body 5a is used, and a rear end boss 5b of the cylinder body 5a is used.
Is fitted to a fitting portion 4e recessed on the front surface of the booster shell 4a, and the connecting flange 5c is bolted to the front surface of the booster shell 4a, so that the hydraulic master cylinder 5 is connected in series to the front portion of the booster 4. Be linked.

The inside of the booster shell 4a is formed by a booster piston 10 made of a thin steel plate and a flexible diaphragm 11 joined to the back of the piston 10, and a negative pressure chamber 12 at the front of the vehicle body and a rear side of the vehicle body. And a working chamber 13. The booster shell 4a is provided with a tapered main body portion 14a of the valve body 14 on the center axis CL, and the valve housing 4b is provided with a large-diameter cylindrical portion 14b that follows the tapered main body portion 14a on the rear side of the vehicle body. Similarly, a push rod 7 having a rear end connected to the operation pedal 8 is provided on the large-diameter cylindrical portion 14b and the small-diameter cylindrical portion 14c formed in the tapered main body portion 14a. The tip side of
The valve housing 4b is disposed so as to protrude from an air inlet 4g that opens in a rear end wall 4f.

The diaphragm 11 has an outer peripheral side bead 11a.
Is sandwiched at the joint between the front half body 4c and the rear half body 4d, and the inner peripheral bead 11b is connected to the booster piston 10
Is mounted between the inner peripheral edge 10a of the valve body 14 and the outer peripheral surface of the tapered main body portion 14a located on the vehicle body front side of the valve body 14.

Booster piston 10 and valve body 14
Is constantly urged toward the rear of the vehicle body by the return spring 15, and the retreat limit of the booster piston 10 is restricted by the contact between the projection 11c of the diaphragm 11 and the rear half body 4d of the booster shell 4a and the valve The filter 1 in which the retreat limit of the body 14 is fitted to the rear end of the large-diameter cylindrical portion 14b.
6 and the rear end wall 4f of the valve housing 4b.

The small diameter cylindrical portion 14c of the valve body 14 is formed with a stepped hole 14d penetrating in the vehicle longitudinal direction, and the valve piston 17 is held in the stepped hole 14d. The valve piston 17 has a receiving hole 17a formed by opening the rear end of the vehicle body.
A spherical head 7a at the tip of the push rod 7 is supported by the swing rod 7a so as to swing. An output rod 1 that pushes the master piston 50 of the hydraulic master cylinder 5 via a plate-like reaction piston 18 is provided on the front end of the small-diameter cylindrical portion 14c on the vehicle body side.
9 is fitted. Further, the first valve body 14
A port 20 and a second port 21 are provided, and the negative pressure chamber 12 and the inside of the tapered main body portion 14a are connected to the first port 2.
0, the working chamber 13 and the outer periphery of the valve piston 17 communicate through the second port 21.

The output rod 19 has a large-diameter shaft portion 19a which is retained by the retainer 22 in the tapered main body portion 14a of the valve body 14, and a master piston 50 on the vehicle body front side of the large-diameter shaft portion 19a. Small-diameter shaft portion 1 that supports rear cylinder 50a
9b are integrally formed. In the large diameter shaft portion 19a,
The distal end side of the valve body 14 is fitted through a plate-shaped reaction force piston 18 into a fitting concave portion 19c opened to the rear end surface.

Cylinder body 5 of hydraulic master cylinder 5
5a, a bottomed cylinder hole 5d is provided so as to open to the rear end face on the booster side, and the above-mentioned master piston 50 is inserted in the cylinder hole 5d so as to be liquid-tight and movable. The master piston 50 has a fitting portion 4e of the booster shell 4a.
, A rear cylinder 50a projecting into the negative pressure chamber 12 is provided.
An engagement hole 50b having a larger diameter than the small-diameter shaft portion 19b of the output rod 19 is provided in the rear cylinder 50a so as to open to the rear end face 50d.

The small diameter shaft portion 19b of the output rod 19 is inserted into the engagement hole 50b of the rear cylinder 50a.
The output rod 19 and the master piston 50 are disposed on the central axis CL by engaging the spherical tip 19d of b with the conical spherical bottom wall 50c of the engagement hole 50b. Thus, the hydraulic master cylinder 5 connects the rear cylinder 50a to the output rod 1.
By overlapping with the small-diameter shaft portion 19b of No. 9,
While shortening the length of the cylinder body 5a, the stroke length of the master piston 50 required for generating the hydraulic pressure is secured.

The engagement groove 50b of the rear cylinder 50a has a spiral groove 5 extending approximately 2/3 from the rear end face 50d.
0e is engraved. The concave groove 50e reduces the thickness of the outer side of the concave groove 50e by its formation, but the rear cylinder 50e
When the master piston 50 tilts sideways from the center axis CL, the rear cylinder 5
The rear cylinder 50a can be easily cut or broken from any part of the groove 50e by colliding the rear end side of the output rod 19 with the small diameter shaft portion 19b of the output rod 19 left on the center axis CL. As in the case of forming a female screw, a tap for threading is formed in the engagement hole 50b.

As described above, in the embodiment, the rear cylinder 5 of the master piston 50 accommodating the small diameter shaft portion 19b of the output rod 19 is provided.
A spiral groove 50e is formed in the engagement hole 50b of the rear cylinder 50a.
Arranged above, there is no contact relationship between the rear cylinder 50a and the small diameter shaft portion 19b. Further, when the front of the vehicle body collides, an excessive external force is applied to the hydraulic master cylinder 5 located on the front side of the vehicle body from the booster 4 from the front of the vehicle body. Axis CL
When the rear cylinder 50a is inclined in any direction, the engagement hole 50b of the rear cylinder 50a collides violently with the small-diameter shaft portion 19b of the output rod 19, and the rear cylinder 50a breaks or breaks from the weak portion where the concave groove 50e is formed. I do.

The degree of inclination of the hydraulic master cylinder 5 is further increased by cutting or breaking the rear cylinder 50a of the master piston 50, and external force from the front part of the vehicle body is surely deviated to the side from the center axis CL. Therefore, the external force hardly acts as a force for pushing the output rod 19 toward the rear part of the vehicle body with respect to the center axis CL. In the booster 4 having the output rod 19, although the front side of the vehicle body is crushed by the inclination of the hydraulic master cylinder 5, the external force from the front side of the vehicle body is surely deviated to the side from the center axis CL, so The valve housing 4b, the push rod 7, and the operation pedal 8 in the chamber 2 can be prevented from being pushed back toward the driver as much as possible.

Further, in the present embodiment, in order to effectively avoid the pushback toward the driver due to the external force from the front part of the vehicle body as described above, the engagement hole 50b of the rear cylinder 50a of the master piston 50 is provided. It is only a simple change to provide the concave groove 50e, and any special processing or exclusive use is required for the respective structures of the booster 4 and the hydraulic master cylinder 5 and their connection structure, or the vehicle body structure including the dash panel 3. Since these members are not required, the number of manufacturing steps, the number of processing steps, and the number of assembling operation steps can be omitted, and the operation can be performed at low cost. In addition, the concave groove 50e requires only a short and simple process of forming a tap, as in the case of forming a female screw, and is therefore extremely excellent in workability.

In the second to fourth embodiments shown in FIGS. 5 to 7, the circumferential groove 5 is formed in the engagement hole 50b of the rear cylinder 50a.
0f, 50g and 50h are provided in a plural number, and the concave groove 50f of the second embodiment shown in FIG. 5 has a square cross section, and the concave groove 50g of the third embodiment shown in FIG. Are formed in an arc shape, and in the fourth embodiment shown in FIG. 7, the cross-sectional shape is formed in a V-shape.

The fifth embodiment shown in FIG.
i is formed in the axial direction of the engagement hole 50b. In the present embodiment, an external force is applied to the hydraulic master cylinder 5 from the front of the vehicle body, and the hydraulic master cylinder 5 When the rear cylinder 50a collides with the small-diameter shaft portion 19b of the output rod 19, the rear cylinder 50a
Breaks by h.

The concave grooves formed in the engagement holes can be set in various shapes and numbers other than the above-described embodiment.
Further, a concave groove may be formed in both the circumferential direction and the axial direction.

[0028]

As described above, according to the vehicle hydraulic pressure generating apparatus of the present invention, an excessive external force such as a collision load acts on the front of the vehicle body, and the hydraulic master cylinder is moved from the front to the rear of the vehicle body. When the master piston is tilted in any direction, the rear cylinder of the master piston is cut or broken by the concave groove, so the inclination of the hydraulic master cylinder is assisted, and external force from the front part of the vehicle body is reliably laterally The valve housing, the push rod, and the operation pedal in the passenger compartment can be prevented from being pushed back toward the driver as much as possible.

The difference from the conventional structure is that only the concave groove is provided in the engagement hole of the rear cylinder of the master piston, and the respective structures of the booster and the hydraulic master cylinder, their connection structure, or the dash panel are used. Since no special processing or special members are required for the body structure to be started, the number of manufacturing steps, processing steps, and assembling work steps can be omitted.
It can be implemented at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a hydraulic pressure generating device showing a first embodiment of the present invention.

FIG. 2 is a front view of the entire hydraulic pressure generator showing a first embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a main part of a hydraulic pressure generator showing a first embodiment of the present invention.

FIG. 4 is an exploded perspective view of a main part of a hydraulic pressure generating device showing a first embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a main part of a hydraulic pressure generating device showing a second embodiment of the present invention.

FIG. 6 is an enlarged sectional view of a rear cylinder showing a third embodiment of the present invention.

FIG. 7 is an enlarged sectional view of a rear cylinder showing a fourth embodiment of the present invention.

FIG. 8 is an enlarged sectional view of a main part of a hydraulic pressure generating device showing a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine room 2 ... Crew room 3 ... Dash panel 4 ... Booster 4a ... Booster shell 4b ... Valve housing 5 ... Hydraulic master cylinder 5a ... Cylinder body 5d ... Cylinder hole 6 ... Hydraulic pressure generator 7 ... Push rod 8 ... Pedal Reference numeral 19: output rod 19a: large-diameter shaft portion 19b: small-diameter shaft portion 50: master piston 50a: rear cylinder 50b: engagement hole 50c: bottom wall 50d: rear end face 50e, 50f, 50g, 50h, 50i: concave groove

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D047 BB00 CC17 CC19 FF01 FF16 JJ01 3D048 BB00 CC26 EE02 EE28 HH55 KK02 KK03 NN03 QQ00

Claims (1)

[Claims] 1. A booster for increasing a pedal depressing force is provided on a side of an engine room of a dash panel for separating an engine room at a front portion of a vehicle body and a passenger compartment following the engine room. A hydraulic master cylinder for converting the increased pedal effort into hydraulic pressure is connected, and a rear cylinder of a master piston inserted into a cylinder hole of the hydraulic master cylinder is arranged so as to protrude into a booster shell of the booster. In the vehicle hydraulic pressure generating device, a small-diameter shaft portion of an output rod of a booster is inserted into an engagement hole inside the rear cylinder, and a tip of the small-diameter shaft portion abuts on a bottom wall of the engagement hole. A hydraulic pressure generating device for a vehicle, wherein an axial or circumferential groove is formed inside an engagement hole of a cylinder.