JPH0678773B2 - Disk break - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a disk brake having a spring material for preventing a drag phenomenon of a friction pad.

(Prior Art) A disc brake is always used in order to prevent the drag phenomenon that the friction pad is kept in contact with the disc even after releasing the braking operation in which the friction pad holds the disc. Some are provided with a spring material that urges the disk in a direction away from the disk.

Conventionally, as a disc brake provided with this spring material, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 61-24540, which is one of the discs 1 as shown in FIGS. 5 and 6. On the side, a carrier 2 is fixed to a non-rotating member of a vehicle, and a pair of friction pads 3 and 4 sandwiching the disc 1 are held on the carrier 2 so as to be slidable in the axial direction of the disc 1. The caliper 5 is slidably held by the caliper support pins 6, 6, and the caliper 5 straddles the disk 1 and the cylinder portion 8 on which the piston 7 facing one friction pad 4 is slid. An opening 10 facing the central portion in the circumferential direction on the circumferential surface of the bridge portion 9 and the friction pads 3 and 4 of the first rank formed on the bridge portion 9.
And a leg portion 11 facing the back surface of the other friction pad 3 are formed, and one spring for preventing the drag of the friction pads 3 and 4 described above is formed in the disc brake configured as described above. The material 12 is provided.

The spring material 12 is used for the bridge portion 9 of the caliper 5.
The backing plates 3a, 4a of the friction pads 3, 4 for connecting the central portions in the circumferential direction on the circumferential surfaces of the pair of friction pads 3, 4 facing each other.
Both ends 13a, 13b of the spring member are inserted into the fitting holes 3b, 4b provided in the spring member 12 so that the curved portion 13 of the spring member 12 faces the opening 10.

Then, in the operation of the disc brake described above, the piston 7 and the caliper 5 are relatively displaced by the pressure oil supplied from the introduction port 8a into the cylinder portion 8 to bring the friction pad 4 on the piston 7 side into contact with the disc 1. On the other hand, the reaction force displaces the caliper 5 with respect to the piston 7 so that the leg portion 11 of the caliper 5 causes the other friction pad 3 to abut against the disk 1, thereby braking the rotation of the disk 1. . When the braking is released, the pair of friction pads 3 and 4 are moved by the spring force generated by the curved portion 13 of the spring member 12 in the direction in which they are separated from the disc 1 to prevent the drag phenomenon.

(Problems to be Solved by the Invention) However, the above spring material 12 has the following problems.

First, since the curved portion 13 of the spring material 12 faces the opening 10 of the bridge portion 9, the curved portion 13 cannot be sufficiently long. Therefore, a large spring force cannot be obtained, and when the friction pads 3 and 4 are worn and the amount of bending of the spring material 12 changes,
Since the spring force changes greatly, there is a problem in that a stable spring force cannot be obtained and the spring force for separating the friction pads 3 and 4 from the disc 1 cannot be secured.

Further, when the friction pads 3 and 4 are worn, the curved portion 13 of the spring material 12 may protrude from the opening 10 of the bridge portion 9 and come into contact with the wheel of the vehicle.

The present invention has been made in view of the above problems, and an object of the present invention is to ensure a stable spring force in a spring material even when the friction pad is worn.

(Means for Solving Problems) The present invention is, as means for solving the above problems and achieving the object, provided so as to be opposed to each other with a disk sandwiched therebetween and to be movable movably toward the disk. A pair of friction pads,
A caliper that straddles the pair of friction pads and the disc and has a bridge portion inside which a recess is formed so as to face the outer peripheral portion of the disc, and presses the pair of friction pads toward the disc. Both ends of the back metal are inserted into fitting holes provided substantially in the center of the back metal in the circumferential direction, and a spring material is provided to apply a spring force in a direction in which the friction pads are separated from each other. A part is inserted into the fitting hole, the middle part of the spring material,
At least two curved portions that generate a spring force are formed so as to be located along the outer circumference of the disc, and the curved portions are provided on the backing plates of the pair of friction pads in the concave portion of the bridge portion. It is arranged such that a line connecting the fitting holes is sandwiched therebetween, and a part is in contact with the inner surface of the recess.

(Operation) With the above configuration, the following operation is performed.

The spring material has a curved part formed along the outer circumference of the disk in the recess of the bridge part, so that the curved part can have a sufficient length, a large spring force can be obtained, and the friction pad wears. As a result, a stable spring force can be obtained even if the amount of flexure changes, and a sufficient spring force for moving the friction pad in the direction of separating from the disc can be secured.

Further, since the spring member is attached so as to be in contact with the inner surface of the concave portion of the bridge portion, it does not protrude from the opening or fall off from the circumferential direction of the disc.

The concave portion is usually provided for relief when machining the inner diameter of the cylinder portion of the caliper and for relief when assembling the piston.

(Embodiment) Next, a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. The same members as those shown in FIGS. 5 and 6 are designated by the same reference numerals and the description thereof will be omitted.

A concave portion 14 is formed inside the bridge portion 9 of the caliper 5 so as to face the outer peripheral portion of the disk 1, and an opening 10 for checking the degree of wear of the friction pads 3 and 4 is formed in the concave portion 14. . The opening 10 faces the central portion in the circumferential direction of the friction pads 3 and 4 and the peripheral surface of the disk 1, and extends in the axial direction of the disk 1.

Next, the spring material 15, which is the main part of the present invention, has two U-shaped curved portions 16 and 17 formed along the outer periphery of the disk 1 at the intermediate portion thereof, and the curved portion 16 Both ends 15a, 15b extending from the
It is bent toward the fitting holes 3b, 4b respectively bored in a, and the both end portions 15a, 15b are inserted into the fitting holes 3b, 4b and attached, and the curved portions 16, 17 are formed. Recessed portion 14 of the bridge portion 9
The disk 1 is arranged along the circumferential direction of the disk 1 with a line connecting the fitting holes 3b and 4b interposed therebetween. Also, with this attached state,
The tips of the curved portions 16 and 17 are attached to the concave portion 14 of the bridge portion 9.
Contact the inner surface.

With the above, the disc 1 by the friction pads 3 and 4
When the brake operation of is released, the curved parts 16 and 17 of the spring material 15 are
The frictional pads 3 and 4 are evenly separated from the disk 1 by the spring force of the. Then, the curved portions 16 and 17 are attached to the disk 1
Since it is formed at two locations along the outer circumference of the friction pad, it is possible to secure a sufficient length and increase the spring force.
Even if the wear of 3 and 4 changes and the amount of bending changes, a spring force sufficient to separate the friction pads 3 and 4 from the disk 1 can be secured.

Further, since the tips of the curved portions 16 and 17 are brought into contact with the inner surface of the recess 14 of the bridge portion 9, both ends 15a and 15b of the spring member 15 are fitted in the backing plates 3a and 4a of the friction pads 3 and 4, respectively. It is possible to regulate the displacement in the direction of coming out from the holes 3b, 4b, and to
It is possible to regulate the escape in the circumferential direction.

Next, a second embodiment will be described with reference to FIG.

The second embodiment differs from the first embodiment in the shape of the spring material and the mounting position of the friction pad on the back metal.

The curved portions 19 and 20 of the spring member 18 are wound one turn, and the spring force can be improved by winding in this way.
Further, the fitting holes 21 and 22 into which the spring member 18 is inserted are displaced from the center of the caliper 5 in the opposite directions along the outer circumferences of the backing plates 3a and 4a of the friction pads 3 and 4 by the dimension A, respectively. And the fitting hole provided in this way
By attaching the spring member 18 to 21,22, the spring force of the spring member 18 causes a moment force to the friction pads 3 and 4. To generate such a moment force does not mean that the dragging phenomenon actually occurs when the entire surface of the friction pads 3 and 4 abuts on the disk 1, but a part of the frictional pad 3 and 4 causes one-sided contact. When the contacting side is separated from the disk 1 by the moment force, it is very effective in preventing drag.

(Effects of the Invention) As described in detail above, according to the present invention, at least two curved portions are formed in the spring material so as to be positioned only in the recessed portion of the bridge portion along the outer circumference of the disc, and Since a part of the portion is attached so as to be in contact with the inner surface of the recess, the length of the curved portion can be set sufficiently, the spring force can be made large and stable, and the friction pad can be separated from the disc even if the friction pad wears. The spring force can be secured and the drag phenomenon can be reliably prevented.

Further, since the spring member is attached so as to be in contact with the inner surface of the bridge portion, it is possible to prevent the spring member from falling off in the radial direction and the circumferential direction of the disc.

[Brief description of drawings]

1 is a partial sectional plan view showing a disc brake of a first embodiment of the present invention, FIG. 2 is a sectional view taken along the line I--I of FIG. 1, and FIG. Partial sectional front view, FIG. 4 is a partial sectional plan view showing a disc brake of a second embodiment of the present invention, and FIG. 5 is a partial sectional plan view showing an example of a conventional disc brake. The drawing is a sectional view taken along the line II-II in FIG. 1 ... Disc 3, 4 ... Friction pad 3a, 4a ... Back metal 3b, 4b ... Fitting hole 5 ... Caliper 9 ... Bridge part 15 ... Spring material 16, 17 ... Curved part

Claims (2)

[Claims] 1. A pair of friction pads that are opposed to each other with a disc sandwiched therebetween and are variably movable toward the disc, and a pair of the friction pads and the disc that straddle the inner side and face the outer peripheral portion of the disc inside. And a caliper for pressing the pair of friction pads toward the disc, and both ends of the calipers for fitting the friction pads toward the disc. And a spring material that applies a spring force to the pair of friction pads in a direction away from each other, and a spring force is generated in the middle part of the spring material whose both ends are inserted into the fitting holes. At least two curved portions are formed along the outer circumference of the disc, and the curved portions are arranged in the recess of the bridge portion so as to be located behind the pair of friction pads. Disc brake disposed across the line connecting the fitting hole provided, and wherein a portion is in contact with both sides of the recess. 2. The disc brake according to claim 1, wherein the fitting holes are provided at positions offset from each other with respect to the central portion of the caliper along the outer circumference of the back metal of the friction pad in opposite directions.