JP2006170251A - Disk brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the vibration of a brake and the squeak of the brake due to a nonuniform contact pressure. <P>SOLUTION: The inner pad of a brake pad is disposed facing the frictional sliding surface of a disk rotor rotating together with wheels. A lining 30a on which a projected part 70 projecting in the circumferential direction of the disk rotor is formed is stuck on the surface of the inner pad 30b not facing the disk rotor. A torque receiving part receiving the braking torque of the inner pad 30b is formed on a mounting fixed to a vehicle body so that it can be brought into contact with the projected part 70 when the lining 30a is pressed. A contact force reducing means 80 for reducing a contact force produced between the projected part 70 and the torque receiving part by the braking torque acting on the inner pad 30b is disposed at a contact portion between the projected part 70 and the torque receiving part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a disc brake, and more particularly, to a technique for reducing disc brake drag in a disc brake caliper.

  In general, in a disc brake, a pair of pads are disposed with a disc rotor sandwiched inside a caliper. The mounting fixed to the non-rotating portion of the vehicle has a pair of left and right support arms spaced between the circumferential directions of the disc, and the support arms are provided with guide holes. A slide pin that is slidably inserted into the guide hole is fixed to the caliper by a bolt. When the caliper moves in the axial direction of the disc rotor via the guide hole and the slide pin, the disc rotor is clamped by the pad to brake the wheel.

  In the disc brake structure, the brake pad may not be pressed uniformly against the disc rotor, or the brake pad may not return to its original position even after the pressure is released. When such a phenomenon occurs, brake vibration or brake squeal due to uneven surface pressure occurs during braking, or uneven wear of the disk rotor occurs.

In view of this, a technique has been devised that makes it easy to return the brake pad after the pressure is released to prevent brake vibration and dragging. For example, a technique (see Patent Documents 1 and 2) in which an urging force opposite to the pressing direction is applied to the brake pad, or a torque receiving portion to which the brake pad is fitted as an inclined surface, A technique (see Patent Document 3) that facilitates return is known.
Japanese Utility Model Publication No. 05-062746 JP 09-296836 A JP-A-8-261261

  However, Patent Documents 1 to 3 do not describe smooth movement of the brake pad on the trailing side of the disk rotor. When the brake pad is pressed against the disc rotor, a contact force is generated in the torque receiving part of the mounting on the trailing side, while a clearance is generated on the leading side. May become unstable and brake squeal or vibration may occur due to uneven surface pressure.

  This invention is made | formed in view of such a condition, The objective is to provide the technique which reduces the brake vibration and brake squeal caused by the nonuniformity of a surface pressure.

  An aspect of the present invention is affixed to a disk rotor that rotates with a wheel, a brake pad that is disposed to face a frictional sliding surface of the disk rotor, and a surface of the brake pad that does not face the disk rotor, Pressing the back plate in a direction parallel to the rotation axis of the disk rotor and pressing the brake pad against the friction sliding surface of the disk rotor A pressing means; a mounting fixed to the vehicle body side; and a torque receiving portion that receives the braking torque of the brake pad by contacting the convex portion when the back metal is pressed; and the contact between the convex portion and the torque receiving portion And a contact force reducing means disposed on the portion.

  According to this aspect, when the brake pad is pressed against the friction sliding surface of the disc rotor, the brake pad can be pressed evenly by the contact force reducing means on the trailing side. Brake vibration and brake noise can be reduced.

  The contact force reducing means includes: an elastic portion formed by juxtaposing a plurality of elastic body pieces; and a thin plate placed on the upper surface of the elastic body piece and contacting the convex portion, wherein the elastic portion is the disk rotor. It may be configured to be deformable in a direction parallel to the rotation axis. According to this, when the brake pad is pressed against the frictional sliding surface of the disc rotor, the elastic portion is deformed so as to fall toward the disc rotor side, so that the movement of the back metal is not hindered. Accordingly, the entire surface of the brake pad is in close contact with the disc rotor, and brake vibration and brake squeal caused by uneven surface pressure can be reduced.

  The contact force reducing means may be two thin plates formed by aligning surfaces with a reduced friction coefficient. In this case, one thin plate is in contact with the convex portion, and the other thin plate is the torque receiving member. It may be affixed to the part. According to this, when the brake pad is pressed against the frictional sliding surface of the disc rotor, one thin plate is dragged by the convex portion and moves to the disc rotor side, and this thin plate is smooth against the other thin plate. Moving. This makes it difficult for the trailing side of the brake pad to be dragged, so that brake vibration and brake noise can be reduced.

  According to the disc brake of the present invention, the brake pad can be pressed evenly left and right by the contact force reducing means on the trailing side, so that it is possible to reduce brake vibration and brake squeal due to uneven surface pressure. it can.

  FIG. 1 shows a disc brake 10 according to an embodiment of the present invention. The disc brake 10 includes a mounting 12 fixed to a non-rotating member of a vehicle (not shown), and a caliper 16 that is slidably supported by the mounting 12. The caliper 16 includes a cylinder portion having a piston 32 therein, and a claw portion (not shown) that extends from the cylinder portion and faces the cylinder portion with the disk rotor 26 therebetween. Between the cylinder part and the claw part inside the caliper 16, an inner pad 30b and an outer pad 28b are arranged to face each other with a disc rotor 26 that rotates coaxially with the wheel. On the side of the inner pad 30b and the outer pad 28b that do not face the disk rotor 26, back metal 30a and 28a are fixed, respectively. The back metal 30 a is supported on the inner side of the disk rotor 26 by the mounting 12 so as to be slidable in the axial direction of the disk rotor 26. The back metal 28 a is supported on the outer side of the disk rotor 26 by the mounting 12 so as to be slidable in the axial direction of the disk rotor 26.

  The above-described cylinder portion of the caliper 16 is disposed on the back portion of the back metal 30a. When the piston 32 is actuated to push the back metal 30a, the inner pad 30b is pushed toward the inner side of the disk rotor 26 (in the direction of the arrow 50 shown in FIG. 1). A claw portion (not shown) of the caliper 16 is disposed on the back portion of the back metal 28a. When the claw portion moves and presses the back metal 28a, the outer pad 28b is pressed toward the outer side of the disk rotor 26 (in the direction of the arrow 52 shown in FIG. 1).

  The mounting 12 includes a pair of arm portions 14 in which guide holes 20 parallel to each other are formed. The caliper 16 includes a pair of caliper arms 18 that extend from the cylinder portion in the circumferential direction of the disk rotor 26. The caliper arm 18 is formed with pin bolt holes 34 parallel to each other for bolting the slide pin 22 to the caliper arm 18. The slide pins 22 are respectively fixed by pin bolts 24 toward the axial direction of the disk rotor 26. The length of the portion of the slide pin 22 that is inserted into the guide hole 20 is larger than the depth of the guide hole 20. The slide pin 22 is slidably inserted into the opposing guide hole 20 with a predetermined gap. Accordingly, the caliper 16 is supported by the mounting 12 in a state in which the caliper 16 can slide in the axial direction of the disk rotor 26 via the slide pin 22.

  In the disc brake 10 configured as described above, when the piston 32 protrudes in the direction of the arrow 50, the inner pad 30b is pressed against the inner side of the disc rotor 26, and the reaction force causes the caliper 16 to move to the piston 32. The outer pad 28b is pressed against the outer side of the disk rotor 26 by a claw portion (not shown). As a result, the disc rotor 26 is clamped by the outer pad 28b and the inner pad 30b, and the wheel is braked.

  A cylindrical pin boot (also referred to as a dust boot) 40 made of a flexible member such as rubber is attached between the base portion of the slide pin 22 and the opening end of the guide hole 20 of the arm portion 14. An annular groove 64 is formed on the inner peripheral surface of the opening end portion of the guide hole 20, and an attachment portion 42 at one end of the pin boot 40 is fitted between the slide pin 22 with a tightening margin in the annular groove 64. Yes. An annular groove 66 is also formed on the outer periphery of the base portion of the slide pin 22, and a mounting portion 62 at the other end of the pin boot 40 is fitted into the annular groove 66. The bellows-like annular connecting portion 60 that connects the mounting portion 42 on the guide hole side and the mounting portion 62 on the slide pin side is thinner than both mounting portions, and follows the sliding displacement of the slide pin 22. It is designed to expand and contract. The annular connecting portion 60 covers the sliding surfaces of the slide pin 22 and the guide hole 20, and prevents foreign matters such as dust and dirt from entering the sliding surface.

  FIG. 2 shows a simplified structure of the mounting 12 and the back metal 30a when the AA cross section of FIG. 1 is viewed from the direction of the arrow in FIG. The mounting 12 has a concave torque receiving portion 72 formed therein. Moreover, the convex part 70 is formed in the both sides | surfaces of the back metal 30a. By fitting the convex portion 70 to the torque receiving portion 72 provided on the mounting 12, even when the inner pad 30b is dragged by the disc rotor 26 during braking, the inner pad 30b faces the disc rotor 26. Can be kept on. A similar convex portion is formed on the back metal 28a, and a torque receiving portion for fitting the same is formed on the mounting 12.

  By the way, when the brake pad is pressed against the disc rotor, a tangential force acts on the brake pad in the tangential direction of the disc rotor, and the convex portion is pressed against the torque receiving portion on the trailing side, so that pressing force is generated at the torque receiving portion. To do. When the brake pad tries to move in the axial direction of the disc rotor, this pressing force generates a contact force in the direction opposite to the moving direction between the torque receiving portion and the convex portion. Prevents smooth movement. On the other hand, since a clearance is generated between the torque receiving portion and the convex portion on the leading side of the brake pad, such a frictional force is not generated. Therefore, when the brake pad is pressed against the disc rotor, the leading side of the brake pad is in close contact with the sliding friction surface of the disc rotor, but the brake pad is not in close contact with the sliding friction surface of the disc rotor on the trailing side. As a result, the surface pressure of the brake pads is unevenly distributed, so that the brake pads are not stably held, and the brake pads vibrate, causing the occurrence of brake noise. In addition, since the followability of the brake pad is reduced with respect to the thickness change during the rotation of the disk rotor, torque fluctuation occurs, which also causes brake vibration.

  Therefore, in this embodiment, by reducing the contact force generated between the torque receiving portion and the convex portion, the followability to the disc rotor of the brake pad on the trailing side is improved, and brake vibration and brake squeal are reduced. I tried to do it.

  FIG. 3 is an enlarged view of the CC cross section of FIG. 2, showing an embodiment of the present invention. The torque receiving portion 72 of the mounting 12 is provided with contact force reducing means 80 for reducing the contact force between the convex portion 70 of the back metal 30a and the torque receiving portion 72. The contact force reducing means 80 includes a thin plate 82 (for example, a thickness of 0.4 to 0.5 mm) made of, for example, SUS steel, and an elastic portion 84 formed of an elastic material such as rubber. The elastic portion 84 includes a plurality of pillars 86. Each column 86 has a rectangular column shape extending in the depth direction of FIG. 3 and is arranged so that the upper ends thereof form the same plane. The intervals between the columns 86 are separated to such an extent that the columns 86 can be deformed in the vertical direction in FIG. The upper end of the column 86 and the thin plate 82 are bonded.

  When the inner pad 30b is pressed against the disc rotor 26, the trailing convex portion 70 is strongly pressed against the thin plate 82 of the torque receiving portion 72, so that a frictional force is generated, and the thin plate 82 is pulled by the back metal 30a. Trying to move to the rotor 26 side. The elastic portion 84 has a configuration in which a plurality of columns are arranged at intervals as described above. Therefore, the elastic portion 84 is relatively easily deformed in the rotation axis direction of the disk rotor. The amount of deformation is small. Therefore, at this time, as shown in FIG. 4, the elastic portion 84 is deformed so as to fall down toward the disk rotor 26, so that the movement of the back metal 30 a is not hindered. As a result, the entire surface of the inner pad 30b comes into close contact with the disk rotor 26, so that it is possible to reduce brake vibration and brake squeal caused by uneven surface pressure. When the pressing force of the inner pad 30 b by the piston 32 disappears, the restoring force of the elastic portion 84 acts in the direction of separating the thin plate 82 from the disk rotor 26. Needless to say, the back metal 28a and the outer pad 28b can have the same configuration as described above.

  When the brake pad is strongly dragged by the disc rotor, in the contact force reducing means 80 having the above structure, the convex portion 70 may push in the thin plate 82, thereby preventing the brake pad from moving smoothly in the axial direction. sell. Therefore, in another embodiment of the present invention, as shown in FIG. 5, as the contact force reducing means 90, two thin plates 92a and 92b made of SUS steel are arranged in surface contact with each other. The thin plate 92 a contacts the convex portion 70, and the thin plate 92 b is attached to the bottom surface of the torque receiving portion 72. Then, lubricating oil or grease is applied between the thin plates 90a and 90b to reduce the friction coefficient. In this configuration, when the inner pad 30b is pressed against the disc rotor 26, as shown in FIG. 6, the thin plate 92a is dragged by the convex portion 70 and moves toward the disc rotor, but the thin plate 92a is smoother than the thin plate 92b. Move to. This makes it difficult for the trailing side of the brake pad to be dragged, so that brake vibration and brake noise can be reduced. Needless to say, the back metal 28a and the outer pad 28b can have the same configuration as described above.

  The thin plates 92a and 92b are not limited to SUS steel plates as long as the frictional force of the contact surface is relatively low and the material has a strength that does not greatly deform due to the convex portion on the trailing side when the brake pad is pressed. A thin resin plate with self-lubricating property may be used.

  The present invention has been described above based on the embodiment. It should be understood by those skilled in the art that these embodiments are exemplifications, and that various modifications can be made to the combination of each component and each processing process, and such modifications are also within the scope of the present invention. Such modifications will be described below.

  A means for applying a force for pulling the brake pad away from the disc rotor when the piston is depressurized may be provided in the torque receiving portion of the brake pad. This will be described with reference to FIG.

  FIG. 7 shows a state when the convex portion of the back metal is viewed from the circumferential direction of the disk rotor. In this embodiment, the convex portion 94 of the back metal 30a is formed in a trapezoidal cross-sectional shape having a short side on the disk rotor 26 side. A support clip 96 formed by bending an elastic plate is fitted into a torque receiving portion (not shown). The support clip 96 is disposed so as to sandwich the convex portion 94 having a trapezoidal cross section from the vertical direction. In this configuration, the convex portion 94 is pushed back in the direction away from the disk rotor 26 by the elastic force of the support clip 96. For this reason, a clearance is formed between the inner pad 30b and the disk rotor 26 when the piston is depressurized, so that drag during depressurization is reduced. As a result, the thickness difference growth of the disk rotor, which becomes a vibration factor of the brake, can be suppressed. When the torque receiving portion into which the support clip 96 is fitted is not subjected to the force of pulling the inner pad 30b away from the disk rotor 26 by the contact force reducing means 90, as in the embodiment shown in FIGS. It is particularly useful.

  Further, by arranging the support clip 96 so that the convex portion 94 is sandwiched from the up and down direction of FIG. 7, the brake pad can be supported rather than sandwiching the back metal 30 a from the direction in which the convex portion 94 protrudes from the back metal 30 a and supporting the back metal 30 a. The back metal 30a can be stably held on the trailing side. Further, as shown in FIG. 8, the convex portion 94 may be sandwiched between the two support clips 96 from above and below, and an elastic force may be applied to the convex portion 94.

1 is an overall configuration diagram of a disc brake according to an embodiment of the present invention. It is AA sectional drawing of FIG. It is a figure which shows the 1st Example of a contact force reduction means. It is a figure which shows the 1st Example of a contact force reduction means. It is a figure which shows the 2nd Example of a contact force reduction means. It is a figure which shows the 2nd Example of a contact force reduction means. It is a figure which shows the support clip arrange | positioned at a torque receiving part. It is a figure which shows another example of the support clip arrange | positioned at a torque receiving part.

Explanation of symbols

  10 Disc brake, 12 Mounting, 14 Arm part, 16 Caliper, 18 Caliper arm, 20 Guide hole, 22 Slide pin, 24 Pin bolt, 26 Disc rotor, 28a Back metal, 28b Outer pad, 30a Back metal, 30b Inner pad, 32 Piston, 70 Convex part, 72 Torque receiving part, 80 Contact force reducing means, 82 Thin plate, 84 Elastic part, 86 Column, 90 Contact force reducing means, 92a Thin plate, 92b Thin plate, 94 Convex part, 96 Support clip.

Claims (3)

A disk rotor that rotates with the wheels;
A brake pad disposed opposite to the friction sliding surface of the disk rotor;
A back metal that is affixed to a surface of the brake pad that does not face the disk rotor and that has a convex portion that protrudes in the circumferential direction of the disk rotor;
A pressing means that presses the backing metal in a direction parallel to the rotation axis of the disk rotor and presses the brake pad against the friction sliding surface of the disk rotor;
A mounting that is fixed to the vehicle body and has a torque receiving portion that receives the braking torque of the brake pad in contact with the convex portion when the back metal is pressed;
Contact force reducing means disposed at a contact portion between the convex portion and the torque receiving portion;
A disc brake comprising:   The contact force reducing means includes: an elastic portion formed by juxtaposing a plurality of elastic body pieces; and a thin plate placed on the upper surface of the elastic body piece and contacting the convex portion, wherein the elastic portion is the disk rotor. The disc brake according to claim 1, wherein the disc brake is configured to be deformable in a direction parallel to the rotation axis.   The contact force reducing means is two thin plates formed by aligning surfaces with reduced friction coefficients, one thin plate is in contact with the convex portion, and the other thin plate is affixed to the torque receiving portion. The disc brake according to claim 1.

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