JPH06300063A - Caliper body of disc brake for vehicle - Google Patents

Abstract

PURPOSE:To improve the fitting property of parts to a cylinder bore, and to downsize and lighten a caliper body by previously unitizing parts to be inserted to a cylinder bore. CONSTITUTION:A spring guide 26 is provided with an outer claw 26a, an inner claw 26b and a spring receiver part 26c. The outer claw 26a is inclined outside in the spring receiver part 26c direction, and the inner claw 26b is inclined inside in the spring receiver part 26c direction. A large diameter cylindrical part 12a of a sleeve piston 12 is formed with an outer groove 12c. A circumferential inner groove 28 is formed at a position of a cylinder hole 8 outside of the large diameter cylinder part 12a. The inner claw 26b is fitted in the outer groove 12c, and the spring guide 26 is fitted to the sleeve piston 12, and among the parts to be inserted to the cylinder hole 8, at least the sleeve piston 12, an adjust bolt 22, a bearing 24, a bearing receiver 25 and an adjust spring 17 are unitized previously, or nearly the whole, which includes an adjust nut 14 and a piston 11 besides the described parts, is unitized previously.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake used in a traveling vehicle such as a four-wheeled vehicle, and in particular, a caliper body having a cylinder hole for which an insertion part is preliminarily unitized to improve the assembling property. Concerning the structure of.

[0002]

2. Description of the Related Art As a disc brake used in a four-wheeled vehicle or the like, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 61-58744. This disc brake is equipped with a parking brake in which a hydraulic type operating mechanism that is operated by depressing the brake pedal is provided with a mechanical operating mechanism that is pulled by a hand lever or a foot pedal. An adjuster, which is a combination of an adjusting bolt and an adjusting nut, is arranged between the sleeve piston on the hole bottom side.

The adjust nut is arranged inside the piston and is screwed into the adjust bolt with a multiple thread. Also, a clutch plate integrally formed with the adjusting bolt,
Between the spring guide attached to the cylinder hole,
The adjusting spring is contracted, and the adjusting bolt is urged toward the bottom of the cylinder hole by the elastic force of the adjusting spring, and the clutch plate engages with the clutch hole of the sleeve piston.

In the adjuster described above, when the lining of the friction pad is worn by a predetermined amount or more, the clutch engagement between the clutch plate and the clutch hole is disconnected, and the adjust bolt is screwed out toward the bottom of the cylinder hole to adjust the nut. The screwing position between and is automatically changed to keep the braking gap between the disc rotor and the friction pad constant.

[0005]

In such a structure, from the assembly of the sleeve piston to the circlip for attaching the spring guide to the cylinder hole,
Although it is the smallest assembly unit, adjustment bolts, bearings, bearing receivers, adjustment springs, and spring guides are provided between the sleeve piston and the circlip. Of course, if the assembling of the sleeve piston and the fitting of the circlip are combined, it is a complicated work that requires a lot of labor and time for many interpolated parts.

The present invention has been made in view of the above circumstances, and an object thereof is to improve the assembling property by unitizing the parts to be inserted into the cylinder holes, and at the same time, The purpose is to reduce the size and weight of the caliper body.

[0007]

In order to achieve the above object, in the first aspect of the invention, a piston is accommodated in the tip opening side of the cylinder hole, and a sleeve piston is accommodated in the bottom side of the cylinder hole. Between the piston and the piston, an adjuster in which an adjustment nut and an adjustment bolt are screwed together is disposed, the adjustment nut is fitted to the piston, and the clutch plate provided on the adjustment bolt and the cylinder hole are engaged. The adjust spring is contracted between the spring guide and the spring guide, and the elastic force of the adjust spring urges the adjust bolt toward the bottom of the cylinder hole to move the clutch plate of the adjust bolt to the sleeve piston. In a caliper body of a disc brake for a vehicle to be fitted in a clutch hole of An outer groove is formed in the stone, and an inner groove is formed between the inner end surface of the piston and the bottom wall of the cylinder hole, and the spring guide is formed in the spring guide and protrudes from the sleeve piston toward the opening of the cylinder hole. Forming one end of the adjustment spring in the spring receiving portion, and the spring guide having an outer claw that inclines outward toward the spring receiving portion and an inward inclination in the same direction toward the spring receiving portion. An inner claw that forms the inner claw, and the inner claw is fitted into the outer groove of the sleeve piston to assemble the spring guide to the sleeve piston, and the maximum movement of the sleeve piston is made between the inner claw and the outer groove. Is set to allow the outer claw to fit in the inner groove of the cylinder hole, and the sleep piston is fixed to the cylinder hole.

According to the second aspect of the invention, the inner groove of the cylinder hole is formed at an outer position of the sleeve piston.

[0009]

The spring guide is mounted on the sleeve piston by fitting the inner claw and the outer groove, and the entire insertion part from the sleeve piston to at least the adjusting bolt or to the piston is unitized in advance. In the unit state, these interpolated parts are assembled at predetermined positions in the cylinder holes.

Since the outer claw of the spring guide has an inclination of outward opening toward the spring receiving portion, when the insertion part unit is inserted into the cylinder hole, it bends inward to allow this, but When the parts unit reaches the predetermined assembly position inside the cylinder hole, the outer claw expands outward and fits into the inner groove of the cylinder hole, and moves in the direction of the opening of the cylinder hole, which is the direction in which the insertion parts unit comes out. Regulate.

In the second invention in which the inner groove of the cylinder hole is formed at the outer position of the sleeve piston, the space between the piston and the sleeve piston is closed, and the cylinder body length can be shortened.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The disc brake 1 is a caliper body 2
In the hydraulic actuation mechanism 3 operated by the brake pedal,
The caliper body 2 is equipped with a parking brake equipped with a mechanical actuation mechanism 4 for a parking brake operated by a hand lever or a foot pedal, and the caliper body 2 is fixed to the vehicle body at one side of the disc rotor 5.
Is supported movably in the disc axial direction via a pair of sliding pins (not shown).

The caliper body 2 has a working portion 2a and a reaction portion 2b which are arranged on both sides of the disc rotor 5 so as to face each other.
And a bridge portion 2c that connects the disc rotor 5 and the outside of the disc rotor 5, and a pair of friction pads 7, 7 sandwich the disc rotor 5 between the action portion 2a and the reaction portion 2b. It is located in. In the action part 2a,
A large-diameter cylinder hole 8 opening to the disk rotor 5 side,
A bearing hole 9 in the direction orthogonal to the cylinder axis and a small-diameter connecting hole 10 connecting the cylinder hole 8 and the bearing hole 9 are formed.

A cylindrical piston 11 having a bottom is accommodated on the tip opening side of the cylinder hole 8, and a stepped sleeve piston 12 is accommodated on the bottom side of the cylinder hole 8. An adjuster 13 is arranged between the pistons 11 and 12, so that the braking gap between the disc rotor 5 and the friction pad 7 can be constantly maintained at a constant interval by the adjuster 13.

The piston 11 is housed in the cylinder hole 8 with the bottom wall 11a facing the disk rotor, and the adjust nut 14 of the adjuster 13 is arranged on the internal central axis of the piston 11. Adjust nut 1
Reference numeral 4 is a coil spring 1 which is contracted between a flange 14a of a head portion and a spring receiver 16 which is restricted in rotation by engaging with a bottom wall 11a and is locked by a circlip 15.
The elastic force of 7 urges the piston 11 toward the bottom wall 11a. Between the cylinder hole 8 and the piston 11,
The hydraulic chamber 18 is defined, and the hydraulic actuating mechanism 3 described above includes the piston 11 and the hydraulic chamber 18, and the hydraulic chamber 18 in the acting portion 2a.
It is composed of a union hole 19 that is bored toward.

The sleeve piston 12 has a large-diameter cylindrical portion 12a arranged in the hydraulic chamber 18, and an O-ring 2 in the connecting hole 10.
It is composed of a small-diameter cylindrical portion 12b that is liquid-tightly accommodated via 0, a large-diameter cylindrical portion 12a and a bottom wall 2d of the cylinder hole 8.
Rotation in the circumferential direction is regulated by a detent pin 21 that is hung around and. The detent pin 21 is fixed in advance to the sleeve piston 12 before being inserted into the cylinder hole 8 by press fitting or screwing. Large diameter cylindrical part 12a
Three outer grooves 12c are formed on the outer peripheral surface of the cylinder, and a large-diameter clutch hole 12d that opens in the direction of the opening of the cylinder hole 8 is formed inside the large-diameter cylindrical portion 12a, followed by a small-diameter fit. A fitting hole 12e is formed, and a conical recess 12f having a pyramid shape is formed on the rear end surface of the small-diameter cylindrical portion 12b.

The adjuster 13 includes the adjusting nut 14 and an adjusting bolt 22 screwed into the nut 14.
It consists of The adjusting bolt 22 is formed integrally with the male screw 22a that is screwed into the adjusting nut 14 with a multiple thread, the rear shaft 22b protruding from the adjusting nut 14 toward the bottom of the cylinder hole 8, and the intermediate portion of the rear shaft 22b. The clutch plate 22c has a large diameter. The rear end of the rear shaft 22b has a fitting hole 12 for the sleeve piston 12.
e is fitted to the clutch plate 22c via a seal member 23,
The outer peripheral tapered surface of the clutch engages with the inner peripheral tapered surface of the clutch hole 12d.

The rear shaft 22 is provided outside the clutch plate 22c.
A bearing 24 and a bearing receiver 25 fitted in b are supported, and the sleeve piston 12 is equipped with a cylindrical spring guide 26. In this spring guide 26, three outer claws 26a and three inner claws 26b are alternately formed at equal intervals on a cylindrical portion on one end side that is a mounting side to the sleeve piston 12, and a cylinder part is provided on the other end side. A spring receiving portion 26 that projects toward the opening of the hole 8 and wraps the outside of the clutch plate 22c and the rear shaft 22b in a stepwise manner.
I have c.

The outer claw 26a is tilted so that the notch tongue formed in the cylindrical portion on the mounting side is pulled up outward and spreads toward the spring receiving portion 26c, and the inner claw 26b is also formed.
Is the one in which this notch tongue is also pushed inward and is inclined so as to be narrowed in the direction of the spring receiving portion 26c, and the tip of the outer claw 26a spreads slightly outside the diameter of the cylinder hole 8 and The tip of the claw 26b has a shape that is slightly inward of the outer groove 12c of the sleeve piston 12.

The spring guide 26 covers the large-diameter cylindrical portion 12a of the sleeve piston 12 with the mounting side cylindrical portion, while fitting the inner claw 26b into the outer groove 12c,
It is assembled to the sleeve piston 12 with one touch. Since the inner pawl 26b is inclined inward toward the spring receiving portion 26c, when an external force is applied to the spring guide 26 in the removal direction, the tip of the inner pawl 26b comes into contact with the side wall of the cylinder hole opening of the outer groove 12c. Regulate this. Further, the diameter of the large diameter cylindrical portion 12a on the bottom side of the cylinder hole is slightly larger than that on the opening side of the cylinder hole.
When an external force in the anti-pull-out direction is applied to, the end of the inner pawl 26b on the bottom side of the cylinder hole (in this embodiment, the same as the end surface of the cylinder portion on the mounting side of the spring guide 26) abuts the side wall of the bottom hole of the cylinder hole of the outer groove 12c. Regulate this.

One end of an adjusting spring 27 is supported by the spring receiving portion 26c, and the adjusting spring 27 is contracted between the spring receiving portion 26c and the bearing receiving 25. The clutch plate 22c and the clutch hole 12d are held in an engaged state by being biased toward the bottom.

Further, by the above-mentioned spring receiving portion 26c, at least the sleeve piston 12, the adjusting bolt 22, the bearing 24, the bearing receiving 25, and the adjusting spring 27 are inserted in the cylinder hole 8 at the minimum assembling unit. Is previously unitized. Further, by screwing the adjusting nut 14 into the adjusting bolt 22, most of the inserted parts up to the piston 11 can be integrated.

An inner groove 28 is provided in the cylinder hole 8 at an outer position of the large-diameter cylindrical portion 12a.
The outer pawl 26a of the spring guide 26 assembled at a predetermined position of the cylinder hole 8 is fitted. As described above, the outer pawl 26a is inclined outward in the direction of the spring receiving portion 26c, and the outer end thereof is slightly outwardly expanded from the bore of the cylinder hole 8, so that the inner pawl 26a is in the middle of insertion into the cylinder hole 8. Bending to allow insertion of the spring guide 26.
When the spring guide 26 reaches a predetermined assembly position in the cylinder hole 8, the outer claw 26a expands outward and fits in the inner groove 28, so that the spring guide 26 does not come out toward the opening of the cylinder hole 8. To regulate.

At the above-mentioned mounting position, the inner claw 26b has a cylinder hole bottom end (in this embodiment, the spring guide 26).
(Equal to the end surface of the cylinder portion on the mounting side) and the end wall of the outer groove 12c on the bottom side of the cylinder hole, a clearance C larger than the maximum stroke of the sleeve piston 12 is set, and the sleeve piston 12 is mechanical The spring piston 26 is prevented from interfering with the sleeve piston 12 even when the actuating mechanism 4 is moved to the maximum in the direction of the opening of the cylinder hole 8.

A cam shaft 29 is provided in the bearing hole 9,
A push rod 31 is rotatably accommodated via a bearing 30, and a push rod 31 is suspended between a cam groove 29 a of the cam shaft 29 and an engagement recess 12 f of the sleeve piston 12. A cam lever 32 is fixed to a protruding shaft portion 29b of the cam shaft 29 with a fixing nut 33, and a coiled return spring 34 is wound around the outer periphery of the fixing nut 33. The cam shaft 29 and the cam lever 32 are The return spring 34 is always biased in the non-operating direction by the torsion force.

A brake wire (not shown) connected to a hand lever or a foot pedal of the driver's seat is connected to the outer end of the cam lever 32, and the cam lever 29 pulled by the brake wire extends from the cam shaft 29 to the push rod. 31, the sleeve piston 12, the adjusting bolt 22, and the adjusting nut 14 constitute the mechanical actuating mechanism 4 described above.

In a normal brake operation using the hydraulic actuating mechanism 3, the hydraulic fluid that has been boosted in the hydraulic master cylinder by depressing the brake pedal is introduced into the hydraulic chamber 18 through the union hole 19 and the piston 11 is moved. By pushing in the disc rotor direction, the one friction pad 7 is pushed to one side surface of the disc rotor 5. Next, due to this reaction force, the caliper body 2 moves in the direction of the action portion 2a, and the reaction portion 2
The reaction force claw 2e of b presses the other friction pad 7 to the other side surface of the disc rotor 5, and a braking action is performed.

In the parking brake operation by the mechanical actuating mechanism 4, the brake wire is pulled by the hand lever or the foot pedal, the cam lever 32 and the cam shaft 29 are integrally rotated in the actuating direction, and the push rod 31 is moved. Move in the direction of the disk rotor. The thrust converted into the push rod 31 is the sleeve piston 1
2, transmitted to the piston 11 via the adjustment bolt 22 and the adjustment nut 14, and pushes the piston 11 toward the disc rotor to press both friction pads 7 and 7 against the disc rotor 5 in the same manner as the hydraulic operation. Then, the braking action is performed.

Since the spring guide 26 is engaged with the cylinder hole 8 side by fitting the outer claw 26a and the inner groove 28, in the above parking brake operation, the adjustment spring 27 is advanced by the forward movement of the sleeve piston 12.
Is being compressed. Since the clearance C is set between the inner claw 26b and the outer groove 12c, the spring guide 26 does not interfere with the sleeve piston 12 even when the sleeve piston 12 moves forward to the maximum extent.

When the braking gap between the disc rotor 5 and the friction pad 7 is within a predetermined range, the adjuster 13 only moves the piston 11 by the amount of backlash between the adjusting nut 14 and the adjusting bolt 22, and does not perform the adjusting operation.

Further, when the above-mentioned braking gap becomes wider than the backlash amount due to repeated braking, the piston 11 and the adjusting nut 14 are adjusted by the adjusting bolt 22 and the adjusting nut 14 during braking by the hydraulic actuating mechanism 3. While filling the backlash between them, it makes a large advance to the disk rotor side, and further the adjust bolt 22 is moved integrally in the disk rotor direction. As a result, the clutch plate 22c is separated from the clutch hole 12d against the elastic force of the adjusting spring 27, and the clutch engagement is released.

The adjusting bolt 22 released from the clutch engagement with the clutch hole 12d is used as the adjusting spring 2
The elastic force of 7 causes it to be extended toward the bottom of the cylinder hole 8, and the clutch plate 22c is again engaged with the clutch hole 12d by the clutch engagement and stopped. As a result, the retracted positions of the piston 11 and the adjustment nut 14 whose braking has been released are changed to the disk rotor 5 side, and the disk rotor 5
A predetermined braking gap is automatically set between the friction pad 7 and the friction pad 7.

In this embodiment, the spring guide 26 is attached to the sleeve piston 12 with one touch by fitting the inner claw 26b and the outer groove 12c, and the spring receiving portion 2
6c allows at least the sleeve piston 12 and the adjustment bolt 22, among the parts inserted into the cylinder hole 8,
The bearing 24, the bearing receiver 25, the adjustment spring 27, or the piston 11 is assembled into a unit as a unit. The unitized insertion part is inserted into the cylinder hole 8 as it is, and when it reaches a predetermined assembly position, the outer claw 26a of the spring guide 26 expands and the inner groove 2 of the cylinder hole 8 extends.
8 and the spring guide 26 is engaged with the cylinder hole 8.

As described above, in this embodiment, most of the interpolated parts to be assembled into the cylinder hole 8 or most of the interpolated parts are unitized in advance and then integrally assembled into the cylinder hole 8. Compared to the conventional method in which the insert parts were assembled one by one with a dedicated jig, the work man-hours can be greatly reduced. Further, since the inner groove 28 of the cylinder hole 8 is formed in a circumferential shape, there is no directivity for inserting the inserted component, and the work is further simplified. Moreover, despite the fact that the insertion parts can be assembled with one touch in this way, the outer claws 26a of the spring guide 26 are fitted into the inner grooves 28 of the cylinder holes 8 after assembly, so that they can fall off inadvertently. There is no.

Further, it is possible to omit the circlip which has conventionally prevented the spring guide from coming off, and further, by omitting the engaging groove for the circlip, the interval between the piston 11 and the sleeve piston 12 is narrowed, and the action portion is removed. Since the length of 2a can be shortened, the weight balance between the action portion 2a and the reaction portion 2b is improved, and the caliper body 2 can be compact and lightweight.

In the above-described embodiment, the inner groove of the cylinder hole is formed at the outer peripheral position of the large diameter cylindrical portion of the sleeve piston. However, in the present invention, this inner groove is formed between the inner end of the piston and the bottom wall of the cylinder hole. You can set it in between. Further, this inner groove may be divided into a number corresponding to the outer claw other than the circumferential shape of the embodiment.

Further, although the sleeve piston of the embodiment is provided with the small diameter cylindrical portion accommodated in the connecting hole, the connecting hole and the small diameter cylindrical portion are omitted so that the sleeve piston is mechanically directly pushed. May be.

[0039]

According to the present invention, the inner spring of the spring guide is fitted into the outer groove of the sleeve piston, and the spring guide is assembled to the sleeve piston. Since most or most of the inserted parts to be assembled into the cylinder hole are integrated into a unit beforehand,
The work of assembling into the cylinder hole can be largely omitted, and the circlip that has conventionally prevented the spring guide from coming off can be eliminated. Furthermore, since the inner claws of the spring guide are inclined inward toward the spring receiving portion, the spring guide can be easily attached to the sleeve piston with one touch.

Further, since the spring guide is provided with the outer claw which is inclined outward toward the spring receiving portion,
The insertion part unit can be easily installed in the cylinder hole with one touch without using a jig, and when the insertion part unit reaches the predetermined assembly position inside the cylinder hole, the outer claw will become the inner groove of the cylinder hole. When fitted, the movement of the cylinder hole in the opening direction of the insertion component unit is reliably regulated.

Further, by forming the inner groove of the cylinder hole at the outer position of the sleeve piston, the length between the piston and the sleeve piston can be shortened, so that the weight balance of the caliper body is improved, and the caliper body is small in size.・ We can reduce weight.

[Brief description of drawings]

FIG. 1 is a sectional front view of a disc brake showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a partially sectional front view of an insertion parts unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disc brake 2 ... Caliper body 3 ... Hydraulic actuation mechanism 4 ... Mechanical actuation mechanism for parking brake 5 ... Disc rotor 7 ... Friction pad 8 ... Cylinder hole 9 ... Bearing hole 10 ... Cylinder hole 8 and bearing hole 9 Small diameter connecting hole 11 ... Piston accommodated at the tip opening side of the cylinder hole 8 ... Sleeve piston 12a accommodated at the bottom side of the cylinder hole 8 ... Large diameter cylindrical portion 12b of the sleeve piston 12 ... Sleeve piston 12 Small-diameter cylindrical portion 12c ... Outer groove 12d ... Clutch hole 13 ... Adjuster 14 ... Adjust nut 18 ... Hydraulic chamber 19 ... Union hole 22 ... Adjust bolt 22a ... Adjust bolt 22 male screw 22b ... Adjust bolt 22 rear shaft 22c ... Clutch plate for adjusting bolt 22 ... Bearing 25 ... Bearing 26 ... Cylindrical spring guide mounted on the sleeve piston 12a ... Outer claw of the spring guide 26b ... Inner claw of the spring guide 26c ... Spring receiving portion of the spring guide 27 ... Bearing receiving 25 and spring receiving portion 26c Adjusting spring 28 contracted between the inner periphery of the cylinder hole 8

Claims (2)

[Claims] 1. A piston is housed in a tip opening side of a cylinder hole, and a sleeve piston is housed in a bottom side of the cylinder hole, and an adjusting nut and an adjusting bolt are screwed between the sleeve piston and the piston. The adjuster is arranged, the adjust nut is engaged with the piston, and the adjust spring is contracted between the clutch plate provided on the adjust bolt and the spring guide engaged with the cylinder hole. In the caliper body of the vehicle disc brake, the elastic force of the adjusting spring biases the adjusting bolt toward the bottom of the cylinder hole to cause the clutch plate of the adjusting bolt to engage the clutch hole of the sleeve piston. An outer groove is formed on the sleeve piston, and the inner end surface of the piston and An inner groove is formed between the binder hole and the bottom wall, and a spring receiving portion is formed in the spring guide so as to project from the sleeve piston toward the opening portion of the cylinder hole. One end of the adjusting spring is formed in the spring receiving portion. The spring guide is formed with an outer claw that inclines outward toward the spring receiving part and an inner claw that also inclines inward toward the spring receiving part. Is fitted into the outer groove of the sleeve piston and the spring guide is assembled to the sleeve piston, and a clearance allowing the maximum movement of the sleeve piston is set between the inner claw and the outer groove, and the outer claw is attached to the cylinder hole. A caliper body for a vehicle disc brake, characterized in that the sleep piston is fitted in the cylinder hole by being fitted in the inner groove. 2. The caliper body for a vehicle disc brake according to claim 1, wherein an inner groove of the cylinder hole is formed at an outer position of the sleeve piston.