JPH075302Y2 - Friction pad return structure for vehicle disc brakes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a disc brake applied to a vehicle such as a passenger car or a motorcycle, and more specifically, to a friction pad arranged on both sides of a disc rotor. The present invention relates to a structure for returning a friction pad in a vehicle disc brake that is pulled back from a disc rotor when not in operation to prevent the lining from being dragged.

[Conventional technology]

With a disc brake that moves the caliper in the axial direction of the disc to perform braking, the caliper can be moved in the axial direction of the disc through sliding pins on the bracket support arms that are arranged side by side on the outer periphery of the disc rotor. The pad guide part provided on both sides of the support arm is provided with a retainer and a pad spring having a retainer part and a pad spring part. The inner diameter side surface of the disc is supported by the retainer part, and the outer diameter side surface of the ear piece is elastically urged in the inner diameter direction of the disk by the pad pressing piece of the pad spring part, and the friction pad is suspended so as to be movable in the axial direction of the disk. There is. (See, for example, Japanese Utility Model Publication No. 63-30824).

The friction pad at the time of non-braking in which the pressure on the disc rotor is released is generally returned by a bid with the disc rotor. Therefore, the friction pad is not sufficiently separated from the disc rotor and the friction pad Since the lining may be dragged by the rotating disk rotor, dragging noise and uneven wear may occur, or the drive system may be overloaded, causing wear and deterioration of fuel economy.
A return structure for a friction pad as disclosed in Japanese Patent No. 179240 has been proposed.

In this technique, a pair of pad return springs formed by bending a wire into a substantially V-shape are interposed between a bracket and a friction pad that is arranged to face each other with a disc rotor interposed therebetween.
This pad return spring extends the center of the folding base to the inside of the bracket to support it, and the tips of both leg pieces that continuously expand to the folding base form a small hole drilled on the upper surface of the back plate of the friction pad. Inserted and installed, both friction pads are
The elastic force of the pad return spring urges it away from the disc rotor.

[Problems to be solved by the device]

In such a pad return structure, since the elastic force of the pad return spring concentrates on the upper part of the friction pad, the friction pad is tilted back and the lower side (disc inner diameter side) of the friction pad is attached to the disc rotor. As it is dragged, sufficient drag prevention cannot be achieved.

Further, since the pad return spring is interposed between the bridge portion of the caliper and the friction pad, the disc brake becomes large in the radial direction of the disc, and it is very difficult to mount the disc brake in a limited space. Will be done.

Therefore, an object of the present invention is to provide a friction pad returning structure capable of surely returning the friction pad from the disc rotor without tilting without increasing the diameter of the disc brake.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the friction pad returning structure of the present invention has a caliper that is disposed so as to straddle a disc rotor and a pair of friction pads facing each other on both sides of the caliper. The support arms of the brackets arranged side by side are supported movably in the disc axial direction via sliding pins, and the pad guide portions provided opposite to both support arms are provided with a retainer portion and a pad spring portion. Attach a retainer and pad spring, support the ear pieces protruding on both sides of the back plate of the friction pad with the retainer section, and repel the ear pieces in the disc inner diameter direction with the pad pressing piece of the pad spring section, In a vehicle disc brake in which a friction pad is movably suspended in the disc axial direction, the pad pressing piece of the pad spring portion serves as a first pad pressing piece. The retainer portion is provided with a second pad pressing piece that repels the ear piece in the disc outer diameter direction so as to face the first pad pressing piece, and both the first and second pad pressing pieces approach the disk rotor. It is characterized in that they are arranged so as to be closer to each other, and that the tabs are formed on the upper and lower edges of the ear piece on the disk rotor side.

[Action]

According to this structure, when the friction pad advances toward the disc rotor during braking, the tapered surface of the ear piece moves to the disc rotor side while expanding the first and second pad pressing pieces of the retainer / pad spring. .

When the pressing of the disk rotor is released, both pad pressing pieces return so as to approach each other while pressing the tapered surfaces of the ear pieces, and the friction pads are separated from the disk rotor. The restoring force of both pad pressing pieces acts evenly above and below the ear piece, and the friction pads are returned without tilting.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

The disc brake 1 includes a pair of support arms 4a (a pair of support arms 4a in which a caliper 3 straddling a disc rotor 2 that rotates integrally with a wheel with a bridge portion 3c is arranged side by side on both sides of the bridge portion 3c on the outer periphery of the disc rotor 2). (Not shown) is a caliper floating type that is movably supported in the disc axial direction via sliding pins 5, and each sliding pin 5 is attached to a mounting arm 3d protruding from both sides of the caliper 3. Pins into which the above-mentioned sliding pins 5 are slidably inserted are attached to respective supporting arms 4a fixed by bolts 6 and extending to a bracket 4 attached to the vehicle body on one side of the disc rotor 2. A hole 4b is provided.

The caliper 3 is formed by connecting the action portion 3a and the reaction portion 3b arranged on both sides of the disc rotor 2 by the bridge portion 3c, and a pair of friction parts is provided between the action portion 3a and the reaction portion 3b. The pads 7 and 7 are opposed to each other with the disc rotor 2 interposed therebetween. On the inner side surfaces of both supporting arms 4a, 4a, the above-mentioned friction pads 7, 7 are held via a retainer / pad spring 8, and a stepped pad guide portion 9, which suspends them so as to be movable in the disc axial direction, 9 are provided facing each other.

Each friction pad 7 is composed of a lining 10 and a back plate 11, and retainers and pad springs 8 are provided on both sides of the back plate 11.
The ear pieces 11a, 11a that are held by the projections are provided in a protruding manner, and the ear pieces 11a are formed with tapered surfaces 11b, 11c at the upper and lower edges on the disk rotor side.

A piston P that advances toward the disc rotor 2 side by the hydraulic pressure supplied to the bottom is inserted in the action portion 3a. When the piston P advances toward the disc rotor 2 side during braking, one friction pad 7 causes the disc rotor 2 to move. Pressed on one side of
Next, due to this reaction, the caliper 3 moves to the acting portion 3a side,
The other friction pad 7 is pressed against the other side surface of the disc rotor 2 by the reaction portion 3b, and a braking action is performed.

The retainer / pad spring 8 includes retainer portions 8a and 8a that smoothly guide the movement of the friction pad 7 and pad spring portions 8b and 8b that elastically rub the friction pad 7 in the disc inner diameter direction.
And a retaining piece 8c for attaching the retainer / pad spring 8 to the support arm 4a.

The retainer portions 8a, 8a extend in L-shape from both lower sides of the connecting piece 8d arranged along the standing wall of the pad guide portion 9, and are mounted on the pad guide portion 9 divided on both sides of the disc rotor 2. It comprises a retainer piece 8e, a mounting piece 8f for enclosing the end portion of the pad guide portion 9, and a second pad pressing piece 8i, which will be described later, formed on the retainer piece 8e.

Also, the pad spring portions 8b, 8b are bent back from the upper side of the connecting piece 8d on the side of the support arm 4a, and the caliper 3
The loop portion 8g is formed so as to project to the side, and the first pad pressing piece 8h which is continuous with the tip of the loop portion 8g and extends in the disc axial direction above the retainer piece 8e.

A second pad pressing piece 8i is formed in each retainer piece 8e by two cuts cut from the disk rotor 2 side, and two sets of second pad pressing pieces 8i vertically opposed to each other with the disk rotor 2 sandwiched therebetween are formed.
1, the second pad pressing piece 8h, 8h, 8i, 8i, the disk rotor 2
Are inclined so that they approach each other as they approach each other.

Retainer / pad spring 8 configured as described above
Wraps the end portion of the pad guide portion 9 with the attachment piece 8f of each retainer portion 8a, and fits the locking piece 8c into the rotor groove 4c recessed inside the support arm 4a to support the support arm 4a. Each of the friction pads 7 is attached, and the upper and lower surfaces of the ear pieces 11a, 11a are pressed and held by the first and second pad pressing pieces 8h, 8h, 8i, 8i with an appropriate elastic force. As described above, the tabs 11b and 11c are formed on the upper and lower edges of the ear piece 11a on the disk rotor side.
The ear pieces 11a are slidably moved in the disc axial direction by contacting the pad pressing pieces 8h and 8i that are inclined and narrowed to the side.

This embodiment is configured as described above, and the ear piece 11a of the friction pad 7 is in the position shown in FIG. 1 when the brake is not operated and the brake is not operated. The second pad pressing pieces 8h, 8i are pressed by an appropriate elastic force to prevent rattling due to traveling vibration or the like.

Next, when the friction pad 7 is pushed by the piston P or the reaction portion 3b by the braking, the ear piece 11a moves to the tapered surface 1
While pushing away both pad pressing pieces 8h, 8i with 1b, 11c, they approach the disk rotor 2 and press the lining 10 against the side surface of the disk rotor 2 to perform a braking action. While this braking action is being performed, the first pad pressing piece 8h that elastically blasts the disk outer diameter side surface of the ear piece 11a tries to float outside the disk due to the sliding contact with the disk rotor 2. Is being deterred.

Further, when the above-described braking action is released, the first and second pad pressing pieces 8h, 8 that have been spread by the forward movement of the ear piece 11a.
Since i recovers while narrowing the gap due to the restoring force, the taper surfaces 11b and 11c of the ear piece 11a are pressed by both pad pressing pieces 8h and 8i.
And the friction pad 7 is separated from the disc rotor 2.

Since the restoring force of both pad pressing pieces 8h, 8i acts evenly on the upper and lower tapered surfaces 11b, 11c of the ear piece 11a, the friction pad 7 is returned without tilting, thereby lining the disk rotor 2 as in the conventional case. Is not dragged, and uneven wear is reliably prevented. The inclination angles of the first and second pad pressing pieces 8h, 8i will change with respect to the tapered surfaces 11b, 11c of the ear pieces 11a at any time when the friction pad 7 moves in the disc axial direction. The first and second pad pressing pieces 8h and 8i are tapered surfaces 1
Since they are inclined in the same direction as 1b and 11c and a part of them is always in contact with each other, smooth movement of the ear piece 11a is not hindered.

Further, according to the present invention, unlike the above-mentioned conventional example, since it is not necessary to interpose a pad return spring separately formed between the bridge portion of the caliper and the friction pad, the disc brake is enlarged in the disc radial direction. It is unnecessary and can be easily installed in a limited space.

In the above embodiment, a part of the retainer portion is the second pad pressing piece, but the present invention makes the entire retainer piece have elastic force, and arranges this in a slanted manner so that the retainer piece itself becomes the second pad.
It may be a pad pressing piece.

[Effect of device]

As described above, according to the friction pad returning structure of the present invention, the ear pad of the friction pad is elastically pressed by the pad spring portion of the retainer / pad spring mounted on the pad guide portion of the support arm in the disc inner diameter direction. A second pad pressing piece that elastically repels the ear piece in the disk outer diameter direction is formed on the retainer part that faces the pad spring part, and both pad pressing pieces approach each other as they approach the disk rotor. The ear pieces that are slanted so as to be sandwiched between both pad pressing pieces have tapered surfaces at the upper and lower edges on the disc rotor side, and the restoring force of both pad pressing pieces is adjusted to the upper and lower sides of the ear pieces. Since the friction pad is pulled back from the disc rotor without tilting, the lining is reliably separated from the disc rotor to prevent brake squeal and drag. It can be reliably prevented.

Also, not only does a special pad return spring become unnecessary, but it is not necessary to increase the size of the disc brake,
It can be easily installed in a limited space.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention, and FIG. 1 shows I-I of FIG.
Sectional view, FIG. 2 is a partial sectional plan view of the disc brake,
3 is a sectional view taken along the line III-III in FIG. 2, FIG. 4 is a perspective view showing a part of the friction pad, and FIG. 5 is a perspective view of the retainer / pad spring. 1 ... Disc brake, 2 ... Disc rotor, 3 ... Caliper, 4 ... Bracket, 4a ... Support arm, 7 ... Friction pad,
8 ... Retainer and pad spring, 8a ... Retainer part, 8b
... Pad spring part, 8e ... Retainer piece, 8h ... First pad pressing piece, 8i ... Second pad pressing piece, 9 ... Pad guide part, 10 ... Lining, 11 ... Back plate, 11a ... Ear piece, 11b, 11c ...
Tapered surface

Claims (1)

[Scope of utility model registration request] 1. A caliper, which is disposed across a disc rotor and a pair of friction pads facing each other on both sides of the disc rotor, slides on a support arm of a bracket arranged in parallel with the caliper on the outer periphery of the disc rotor. The friction pad is equipped with a retainer and a pad spring having a retainer portion and a pad spring portion, which are attached to the pad guide portions which are movably supported in the disc axial direction via pins and are provided opposite to each other on both supporting arms. The ear pieces protruding to both sides of the back plate are supported by the retainer section, and the pad pressing section of the pad spring section elastically pierces the ear pieces in the disc inner diameter direction to suspend the friction pad so that it can move in the disc axial direction. In the disc brake for a vehicle, the pad pressing piece of the pad spring portion serves as a first pad pressing piece, and the ear piece is provided on the retainer portion in a disc outer diameter direction. The second pad pressing piece emanating elastically first
The first and second pad pressing pieces are provided so as to face the pad pressing piece, and the first and second pad pressing pieces are arranged so as to be inclined toward each other as they approach the disk rotor. A friction pad return structure for a vehicle disc brake, characterized in that each of them has a tapered surface.