JPS6157498B2 - - Google Patents

Abstract

PURPOSE:To prevent uneven friction of pads by a method wherein a lever is pivotably supported in a holding member floatably supporting a caliper and a pair of pads are forcibly cooperated by a lever action thereof to contact with or separate from surfaces of both sides of a disc rotor. CONSTITUTION:When a piston 8 is advanced to the left by increasing a hydraulic pressure in a cylinder 7 upon braking, a right side pad 10a and a back metal 11a are also moved into the same direction and a lever 23 is pivoted about a pin 22 by engaging with an engagement groove 19 of a connecting member 18. Then, the lever 23 is engaged with an engagement groove 17 of a caliper 4, thereby, the caliper 4 and a left side pad 10b are moved to the right and are pressed against a disc rotor 3 to brake it. If a braking operaion is effected when the pad 10a is worn and a clearance between the rotor 3 is increased, for example, the pin 22 is displaced position, thereby, a desired braking may be effected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention supports a caliper placed astride a disc rotor in a freely floating manner on a holding member, and moves a pair of pads onto the plate surfaces on both sides of the disc rotor by advancing a piston provided on the caliper. It relates to a floating caliper type disc brake in which the pads are pressed against each other to suppress their rotation, and the pair of pads are separated from the plate surface of the disc rotor by retracting the piston. This invention relates to a disc brake in which a pair of pads are forcibly interlocked by lever action to move toward and away from a disc rotor.

Floating caliper type disc brakes, in which a caliper placed astride a disc rotor is supported freely floating, and a piston is installed on one side of the caliper, are widely used in vehicles. When the piston advances, it presses the pad on one side against the disc rotor, and when the piston advances further, the reaction force causes the caliper to move in the opposite direction and press the pad on the other side against the disc rotor. The problem was that the amount of wear on both pads was uneven. In addition, even if the pad on one side separates from the plate surface of the disc rotor as the piston retreats when the brake is released, the caliper is not designed to actively move back.
If the pad on the other side does not separate from the disc rotor, and the sliding resistance increases due to foreign matter such as rust or mud intervening in the sliding parts of the caliper and the holding member, the disc rotor and the pad on the other side may could easily come into contact with each other and cause the so-called "dragging" phenomenon. This dragging of the brakes not only causes abnormal wear of the pads, puts an unnecessary load on the engine and increases fuel consumption, but also leads to overheating of the brakes and even vapor lock, which is extremely dangerous.

The present invention aims to eliminate such drawbacks of the conventional floating caliper type disc brake, and its gist is that a lever is pivotally supported on a holding member that freely supports the caliper. The lever action forces the pads on both sides to move toward and away from the disc rotor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

In the figure, 1 is a mounting bracket (holding member) fixed to a vehicle body, etc., and 3 is a disk rotor that rotates together with a rotating body such as a wheel. 4
is almost saddle-shaped as a whole, and the disc rotor 3
The caliper is disposed straddling the support arms 5, 5 which are projecting in the shape of wings, and sliding holes 6, 6 are bored therein. The sliding holes 6, 6 are almost tightly fitted into the plate surfaces 3a, 3b of the disc rotor 3.
It is supported freely floating in the direction perpendicular to the This caliper 4 is integrally formed with an open cylinder 7 on the side of the disc rotor 3 in the center.
A piston 8 with an open front is slidably fitted into the cylinder 7, and a disc rotor 3
On the opposite side of the cylinder 7, a corresponding reaction portion 9 is integrally molded. 10a, 10
b is a pair of pads arranged on both sides of the disc rotor 3, each pad sliding in a direction perpendicular to the plate surfaces 3a, 3b of the disc rotor 3 by fitting with the mounting bracket 1 in a concave and convex manner. It is fixed to the corresponding surfaces of a pair of backing metals 11a and 11b which are freely supported. The pad 10a on one side is
A spring 1 is fixed to the back surface of the back metal 11a with screws 13, 13 and is in elastic contact with the inner surface of the piston 8.
The pad 10b on the other side is pressed against the reaction part 9 of the caliper 4 by a spring 14 fixed to the back surface of the back plate 11b with a screw 15. Moves integrally with Caliper 4. Further, a piston seal 16 is fitted into an annular groove 7a formed on the inner surface of the cylinder 7, and its inner peripheral edge is in elastic contact with the piston 8.

The support arms 5, 5 of the caliper 4 have openings 1.
Engagement grooves 17, 17 are formed whose insides are wider than 7a, and connecting members 18, 18 protruding from both sides of the back surface of the back metal 11a of one pad 10a are also widened inside from the opening 19a. An engagement groove 19 is formed. On the other hand, the mounting bracket 1 is provided with protruding arms 20, 20 having elongated holes 21 perpendicular to the plate surfaces 3a, 3b of the disk rotor 3. Therefore, the levers 23, 23 are pivotally supported, and both ends of each lever 23 are almost tightly fitted into the openings 17a, 19a, respectively, and project into the engaging grooves 17, 19.

The support structure for the arm 20 of each lever 23 is
To explain based on the figure, the lever 23 has a support hole 24 with a circular cross section and a fitting hole 25 with a rectangular cross section that intersects the support hole 24 at right angles to the support hole 24, and the arm 20 is loosely fitted into the fitting hole 25. and lever 23 are connected by a stepped bolt-shaped pin 22 rotatably inserted into a support hole 24 and a nut 26 screwed onto the pin. A rubber bushing 27 is fitted onto the pin 22, and when the nut 26 is tightened, the rubber bushing 27 is compressed, expands in the radial direction, and comes into elastic contact with the side wall surface of the elongated hole 21 of the lever 20, and due to its frictional engagement force, The pin 22 and lever 23 are configured to be held at arbitrary positions in the elongated hole 21.
Note that the head of the pin 22 or nut 26 and the lever 2
Washers 28 and 29 are interposed between the bolts 3 and between the stepped portion of the bolt 22 or the end of the nut 26 and the arm 20, respectively.

Next, the operation of this embodiment will be explained based on FIG. First, by increasing the oil pressure in the cylinder 7 and moving the piston 8 to the left in the figure, the right pad 1
0a and its back metal 11a also move in the same direction, and the lever 23 is engaged with the engagement groove 19 of the connecting member 18.
rotates about the pin 22 as a fulcrum. Then, due to the engagement between the engagement groove 17 of the caliper 4 and the lever 23, the caliper 4 and the pad 10b on the left side move to the right, and the pads 10a, 10b on both sides are interlocked to move the plate surface 3a, 3b, and tighten this disc rotor 3 from both sides. Next, when the oil pressure in the cylinder 7 is lowered to release the brake, the piston 8 retreats into the cylinder 7 due to the elastic restoring force of the piston seal 16.
Due to the frictional engagement force of the springs 12, 12, the right side pad 10a and back metal 11a also move to the right together with the piston 8 and are separated from the plate surface 3a of the disc rotor 3. At this time, the engagement of the connecting member 18 Since the lever 23 rotates about the pin 22 by engagement with the groove 19, the engagement groove 17 of the caliper 4 rotates.
Due to the engagement of the lever 23 with the lever 23, the caliper 4 moves to the left, and the left pad 10b also separates from the plate surface 3b of the disc rotor 3.

As a result of using it for a certain period of time in this way, as shown in FIG. 3, if the right pad 10a wears more rapidly than the left pad 10b and the gap between it and the plate surface 3a of the disc rotor 3 increases, During braking, even if the left pad 10b contacts the plate surface 3b of the disc rotor 3, the right pad 10a is separated from the plate surface 3a of the disc rotor 3, but the pin 22, which is the fulcrum of the lever 23, , the elongated hole 2 of the arm 20 is opened by the frictional engagement force of the rubber bush 27.
1, so when the piston 8 advances further, the lever 23
A clockwise rotating force using the engagement groove 17 as a fulcrum acts on the pin 22, which overcomes the frictional engagement force of the rubber bush 27 and moves to the left in the elongated hole 21, causing the right pad 10a to move toward the disc rotor 3. is pressed against the board surface. Thereafter, the pin 22 serves as a fulcrum for the lever 23 at that position. left pad 1
When 0b is worn, the pin 22 moves to the right, contrary to the above.

As described above, in this embodiment, since the pin 22 has an automatic adjustment function, the pads 10a and 10b on both sides
Even if the amount of wear is uneven, the disk rotor 3 has the advantage of always being able to be tightened with equal force from both sides. It may be immovably supported on the bracket 1.

In addition, if the caliper 4 has high rigidity, both engagement grooves 1 can be opened from the center of the support hole 24 of the lever 23.
If the distances to 7 and 19 are made equal, the lever ratio will be 1:1, and the pads 10a and 10b on both sides will be interlocked by the same distance, and the plate surface 3 of the disc rotor 3 will be moved.
a, 3b, but if the caliper 4 is elastically deformed by the clamping force during braking, the left side must be moved back to the left by a large amount when the brake is released. Since the pad 10b may not be separated from the plate surface 3b of the disk rotor 3,
In that case, the lever ratio is set to an appropriate value.

Also, connect one end of the lever 23 to the left pad 10b.
(To be more precise, it engages with the engagement member fixed to the back metal 11b), and the other end engages with the piston 8, the effect is the same;
Since the pads 10b are integrally fixed to the back metals 11a and 11b, the lever 23 is attached to each pad 10a and 10b.
It is clear that the idea of the invention is exactly the same even if it is directly engaged with 0b.

In addition, an elastic body that is torsionally deformed by the rotation of the lever 23 may be provided at the pin 22, or an elastic spring may be interposed between the back metals 11a and 11b on both sides, so that the elastic restoring force of these springs can cause the pad to open. 10a,1
0b may be separated from the disk rotor 3, and in this case, it is unnecessary to provide the piston seal 16 with a retracting function for making the piston 8 move back.

As clarified by the above explanation, the floating caliper type disc brake of the present invention has a lever pivotally supported on a holding member (mounting bracket in the above embodiment) that supports the caliper in a freely floating manner. The action forces the pair of pads to interlock and move them toward and away from the plate surfaces on both sides of the disc rotor, so during braking, the pair of pads are simultaneously pressed against the plate surfaces on both sides of the disc rotor, creating a brake feeling. This is an excellent product that can prevent the pair of pads from wearing unevenly, and when the brake is released, the pads on both sides can be forcibly separated from the plate surface of the disc rotor, reliably preventing the dragging phenomenon. be effective.

[Brief explanation of the drawing]

The attached drawings show an embodiment of the present invention, in which FIG. 1 is an overall sectional view, FIG. 2 is an enlarged sectional view taken along the line A-A in FIG. 1, and FIG. It is a sectional view of the main part in a state where the pad is worn more than the pad 10b. 1... Holding member, 3... Disc rotor, 3
a, 3b... plate surface, 4... caliper, 8... piston, 10a, 10b... pad, 17, 19...
...Engagement groove, 21...Long hole, 22...Pin, 23...
…lever.

Claims (1)

[Scope of Claims] 1. A caliper placed across a disc rotor is supported by a holding member so as to be free to float in a direction perpendicular to the plate surface of the disc rotor, and a caliper is placed on one side of the disc rotor. The caliper is provided with pistons that move forward and backward in opposition, and a pair of pads are arranged on both sides of the plate surface of the disc rotor, and when the piston advances, the pads on one side are moved by the piston, and the pads on the other side are moved by the caliper. In the floating caliper type disc brake, the disc rotor is pressed to tighten the disc rotor, and the clamping is released by retracting the piston. A configuration in which the lever is engaged with a pad or the piston, and the other end of the lever is engaged with the pad on the other side or the caliper, so that the pair of pads interlock with each other to approach and separate from the plate surface of the disc rotor. A floating caliper type disc brake characterized by: 2. The floating caliper type disc brake according to claim 1, wherein the lever is supported so as to be movable with a force equal to or greater than a set value with respect to a holding member.