JPH08145087A - Disk brake - Google Patents

Abstract

PURPOSE: To assemble a disc brake by advancedly bringing a piston into a caliper linearly from an oblique upside. CONSTITUTION: A flank 20 to gradually enlarge the width of a recess 9 is provided at the tip part of a pair of pawl parts 8 of a caliper 1 supported floatably by a carrier. A piston 2 is advanced linearly from an oblique upside into a caliper 1 with the relief surface 20 used as a guide according to the movement of a robot for assembling the piston 2 inside the bore of the caliper 1.

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 for braking a vehicle.

[0002]

2. Description of the Related Art As a disc brake, a cylinder portion, a disc path portion extending over the disc from the cylinder portion, and a pair of disc brake portions extending inward from the tip of the disc path portion in a radial direction of the disc. A caliper consisting of a claw portion is supported by the carrier fixed to a non-rotating portion of the vehicle so that the caliper can float, and the caliper is supported by the carrier by relative movement of the piston and the caliper stored in the bore of the cylinder portion. There is one in which a pair of pads are pressed against the disc.

10 and 11 show a caliper and a piston which constitute such a disc brake. In both figures, 1 is a caliper, 2 is a piston,
The piston 2 is slidably accommodated in the bore 3 in the caliper 1 via a seal ring 4 and a boot 5. The caliper 1 has a normal cylinder portion 6,
It is integrally formed by casting into a shape including the disk path portion 7 and the pair of claw portions 8, and the inner surface of the bore 3 in the cylinder portion 6 and the inside of the bore 3 for fitting the seal ring 4 and the boot 5 therein. The annular grooves 3a and 3b, the pad pressing surface 8a of the claw portion 8 for pressing the pad, and the like are finished by machining. On the other hand, the piston 2 is usually integrally formed by forging so as to have a bottomed cylindrical shape, and the outer peripheral surface thereof, the annular groove 2a for fitting the boot 5 or the pad pressing surface 2b for pressing the pad are machined. Finished by processing.

The caliper 1 is supported by a carrier, which will be described later, through a pair of left and right arm portions 6a provided integrally with the cylinder portion 6 of the caliper 1. Further, the recess 9 (FIG. 8) between the pair of claw portions 8 of the caliper 1 is used as a space into which a tool for processing the bore 3 is inserted. Further, the disc path portion 7 of the caliper 1 is usually formed with an opening (window) 10 for visually observing the wear amount of the pad.

By the way, one end of the boot 5 is fitted and held in the annular groove 3b on the inner circumference of the bore 3 and the other end is fitted and held in the annular groove 2a on the outer circumference of the piston 2. When assembling the piston 2 to 1, it is necessary to previously fit not only the seal ring 4 but also one end of the boot 5 into the annular grooves 3 a and 3 b in the bore 2. On the other hand, in this type of disc brake, it is necessary to make the disc path length L ₁ of the caliper 1 as short as possible in order to improve efficiency. Therefore, particularly for a solid disc rotor, a rotor (disc) is required. Is thin, the total length L _{2 of the} piston 2 is a value approximate to the disc path length L ₁ (of course, L ₁ > L ₂ ).

For this reason, for automatic assembly by, for example, a robot, as shown in FIG. 11, the piston 2 is arranged laterally (horizontally) with respect to the caliper 1 which is positioned upright so that the bore 3 faces upward. However, there is a possibility that the piston 2 may come into contact with the boot 5 and flip it over, so that there is no choice but to abandon the automatic horizontal assembly by the actual robot. Therefore, conventionally, as shown in FIG. 12, the caliper 1 (the axis of the bore 3).
Inclining the piston 2 against the caliper 1 from diagonally above
It had adopted an automatic assembly method that allowed it to enter inside.

[0007]

However, according to the above assembling method from diagonally above, the recess 9 between the pair of claw portions 8 has the minimum necessary size (width) for allowing the insertion of the tool. Therefore, it is difficult to linearly move the piston 2 from diagonally above without interfering with the claw portion 8, and it is necessary to make the robot make complicated movements. There was a problem that the cost would rise due to extension. In order to solve the above problem, when the recess 9 is simply enlarged, the wall thickness of the radius (R) bottom (the connecting portion of the pair of claw portions 8) 9a and the width of the claw portion 8 itself become small. This leads to a lack of intensity, and also causes an increase in abnormal noise (squeaking noise).

The present invention has been made in view of the above-mentioned problems of the prior art. The problem is that the piston can be linearly inserted into the caliper from diagonally above, and the caliper can be assembled. It is to improve the attachability significantly.

[0009]

In order to achieve the above object, the invention according to claim 1 provides a cylinder part, a disk path part extending from the cylinder part across a disk, and a disk path part. A caliper composed of a pair of claws extending inward from the tip in the radial direction of the disk is provided, the caliper is supported in a floating manner on a carrier fixed to a non-rotating portion of the vehicle, and is stored in the bore of the cylinder portion. In a disc brake that presses a pair of pads supported by the carrier against a disc by relative movement of a piston and the caliper, the width of the recess between the claw portions of the caliper is expanded on the tip side of the claw portion. It is characterized in that it is configured as follows.

According to the present invention, the recess forming surface and the pad pressing surface of the claw portion of the caliper can be connected by a taper surface, and an opening is provided in the caliper disk path portion in the vicinity of the bore. Alternatively, the peripheral edge of the piston on the pad pressing surface side can be a tapered surface.

Further, according to a fifth aspect of the present invention, the cylinder portion, the disk path portion extending from the cylinder portion across the disk, and the tip of the disk path portion are extended inward in the radial direction of the disk. A caliper composed of a pair of claws, the caliper being supported in a floating manner on a carrier fixed to a non-rotating portion of the vehicle, and the relative movement between the piston and the caliper housed in the bore of the cylinder portion In a disc brake which presses a pair of pads supported by a carrier against a disc, the periphery of the piston on the pad pressing surface side is a tapered surface.

[0012]

In the disc brake according to the first aspect of the invention, the piston can be linearly advanced into the disc path portion of the caliper from diagonally above through the expanded portion of the recess on the tip side of the claw portion.

In addition, when the recess forming surface and the pad pressing surface of the claw portion of the caliper are connected by a tapered surface, or when the periphery of the piston on the pad pressing surface side is a tapered surface, the piston and the claw portion are The interference of can be avoided more reliably. Further, when the disc path portion of the caliper is provided with the opening in the vicinity of the bore, the piston can be rotated by utilizing the opening, and the positioning of the piston to the mounting position becomes extremely easy.

Further, in the disc brake according to the fifth aspect, since the peripheral edge of the piston, which is most likely to interfere with the claw portion of the caliper, is a tapered surface, the piston is linearly advanced into the caliper from diagonally above. be able to.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show the overall structure of a disc brake according to the present invention. The overall shapes of the caliper 1 and the piston 2 are shown in FIG.
Since it is the same as that shown in FIGS. 1 and 12, the same parts are designated by the same reference numerals, and the description thereof will be omitted. 1 and 2, the caliper 1 is slidably supported by a support portion 12 of a carrier 11 fixed to a non-rotating portion of a vehicle using a pin 13. The support 12 of the carrier 11 is extended so as to straddle the disk D, and
A pair of pads 14 and 15 arranged on both sides of is supported slidably. Each of the pads 14 and 15 comprises a back plate 16 and a lining material 17 joined to the surface of the back plate 16 (FIG. 2), and the lining material 17 faces the disk D. A so-called squeal preventing shim 18 is attached to a pad (outer pad) 15 outside the vehicle (FIG. 1).

In such a disc brake, when pressure oil is supplied into the bore 3 of the caliper 1, the piston 2 extends and the pad 14 on the inside of the vehicle is pressed against one side of the disc D, while the reaction causes the caliper to move. 1 moves relative to the piston 2, and the pad 15 on the outside of the vehicle is pushed by the claw portion 8 of the caliper 1 and is pushed against the other surface of the disc D, whereby a braking force is generated.

However, in this embodiment, as shown in FIGS. 3 and 4, the side surface (recess forming surface) 8 which is the tip of each claw portion 8 of the caliper 1 and is located on the recess 9 side.
The b is released toward the side of the claw 8 toward the side opposite to the recess 9, and a flank 20 is formed there. The flanks 20 have the same inclination angle with the two claws 8, so that the recess 9 is gradually expanded toward the tip of the claw 8. The radius bottom 9a of the recess 9 is formed in the same size as the conventional one,
Therefore, the thickness of the rounded bottom 9a is the same as the conventional one. In addition, the width l ₂ of the recess 9 on the tip side of the claw portion 8
Is, as an example, the width l ₁ of the recess 9 in the R bottom 9a.
Is wider than 6mm.

In this case, the expansion area of the claw portion 8 with respect to the recess 9 corresponds to the center position of the bore 3 of the caliper 1.
It is preferable in terms of rigidity that the hook is applied to the tip of the claw portion 8 from the position closer to the tip than the height position. That is, if the rigidity of the claw portion 8 is secured as a recess diameter up to the height position of the claw portion 8 corresponding to the center position of the bore 3 of the caliper 1,
From the position closer to the tip than the height position of the claw portion 8 corresponding to the center position of the bore 3 of the caliper 1 of the claw portion 8 to the tip portion, the strength of the claw portion 8 is not so affected, and the piston assembly property is not impaired. The reason for this is that the width of the recess 9 on the tip side of the claw portion 8 can be increased. Therefore, the width of the recess 9 on the tip end side of the claw portion 8 is determined in consideration of the diameter and length of the piston 2, the initial assembly direction angle of the piston 2, and the like.

Further, in the present embodiment, as shown in FIGS. 3 and 4, the recess forming surface 8b and the pad pressing surface 8a of the claw portion 8 of the caliper 1 are connected to each other by the tapered surface 21. The opening 10 of the disk path portion 7 of the caliper 1 is provided close to the bore 3. The flank 20, the tapered surface 21, and the opening 10 are preferably formed integrally with the casting of the caliper 1, but may be formed by machining after casting.

In the disc brake constructed as described above, in order to assemble the piston 2 into the bore 3 of the caliper 1 by the robot, first, as shown in FIGS. 5 and 6, with respect to the caliper 1 (the axis of the bore 3). The piston 2 is tilted so as to enter the disc path portion 7 through the recess 9 from diagonally above. At this time, the flanks 20 of the claws 8 gradually escape outward as they approach the tip of the claws 8, and the left and right claws 8 have the same inclination angle, so that the pair of flanks 20 are inclined. It matches the outer peripheral surface of the piston 2 in the state, and ensures the linear movement of the piston 2. Further, the taper surface 21 on the back side of the claw portion 8 allows the piston 2 to enter into the recess 9 to a greater extent, so that the piston 2 surely reaches the inner side of the disc path portion 7. There is.
Then, as an example, it is desirable that the size of the taper surface 21 is formed by a taper surface (C2) having an angle of 45 degrees by adding to the length of at least 2 mm along the surface direction of the pad holding surface.

FIG. 7 shows a state in which the piston 2 reaches the inner side of the disc path portion 7, and the piston 2 is
At this position, the posture is changed from the inclined state to the upright state by the movement of the robot. At this time, the opening 1 of the disk bus portion 7
Since 0 is formed closer to the bore 2, that is, closer to the bore 3 side than the center position in the thickness direction of the disk D, the lower edge 2c of the piston 2 rolls in the opening 10, and the piston 2 Posture is smoothly changed. After this posture change, air is supplied into the bore 3 to inflate the boot 5, and the piston 2 is pushed into the bore 3 by the movement of the robot, whereby the assembly process is completed.

In the present embodiment, in particular, the taper surface 21 provided between the recess forming surface 8 of the claw portion 8 of the caliper 1 and the pad pressing surface 8a causes burrs when machining the pad pressing surface 8a. This is advantageous in cost because it eliminates the need for subsequent deburring work. Also, bore 3
The opening 10 of the disk path portion 7 provided in the vicinity of acts to smoothly release the cutting oil when processing the bore 3.
It contributes to the improvement of processing efficiency.

In the above embodiment, in addition to providing the clearance surface 20 on the claw portion 8 of the caliper 1, the tapered surface 21 is provided on the back side of the claw portion 8 and the opening 10 of the disk path portion 7 is provided with the bore 3. However, in the present invention, both or at least one of the tapered surface 21 and the opening 10 can be omitted.

Further, in the above-mentioned embodiment, the shape of the caliper 1 is changed to improve the assemblability. However, the present invention may be changed to a shape on the piston 2 side instead. is there. FIG. 8 shows a piston 2 whose shape has been modified from this point of view. A tapered surface 22 is provided on the peripheral edge of the piston 2 on the side of the pad pressing surface 2b (in the figure, the dotted line is the conventional ridge line). ). The tapered surface 22 is formed by inwardly sloping toward the pad pressing surface 2b side with a portion near the annular groove 2a for fitting the boot 5 as a starting point. A peripheral edge of the piston 2 on the side of the pad pressing surface 2b is a portion which most easily interferes with the claw portion 8 of the caliper 1 when the piston 2 is obliquely advanced to the caliper 1, and this portion is a tapered surface 22. As a result, as shown in FIG. 9, when the piston 2 is inserted obliquely from above toward the caliper 1 (the same as that shown in FIG. 11) having the same shape as the conventional one, the tapered surface 22 escapes from the claw portion 8, The piston 2 can be moved linearly as in the above embodiment. Needless to say, the piston 2 provided with the tapered surface 22 can be used together with the caliper 1 in the above embodiment.

Further, when the disc brake having the piston provided with the tapered surface 22 is applied to the disc brake of the drum-in disc brake device, the back plate of the parking drum brake and the pad of the piston 2 of the disc brake are used. A gap with the mouth on the 14th side can be secured by the size of the tapered surface 22 even when the pads 14 and 15 are fully worn, so that it is easy to throttle the peripheral portion of the packing rate of the parking drum brake. Alternatively, the diameter of the back plate can be increased, that is, the size of the drum brake can be increased.

[0027]

As described in detail above, claim 1 is as follows.
According to the disc brake described in (1), since the piston can be linearly moved from diagonally above and assembled to the caliper through the expanded portion of the recess on the tip side of the claw portion,
Assembling is good, and not only can the assembly time be shortened when performing automatic assembly by a robot,
Cost reduction can be achieved. Further, since the tool for processing the bore of the caliper can be easily moved in and out of the recess, the processing time can be shortened, and the cost reduction can be achieved also from this aspect. Further, according to the disc brake of the fifth aspect, since the tapered surface at the peripheral edge of the piston functions as a clearance for the claw portion of the caliper, the piston can be linearly moved obliquely from above and assembled to the caliper. Of course, the manufacturing becomes simpler than when the shape of the caliper is changed.

[Brief description of drawings]

FIG. 1 is a front view showing the overall structure of a disc brake according to the present invention.

FIG. 2 is a plan view showing the overall structure of the present disc brake.

FIG. 3 is a cross-sectional view showing a structure of a caliper that constitutes the present disc brake.

FIG. 4 is a sectional view taken along the line BB of FIG.

FIG. 5 is a cross-sectional view showing an assembled state of a piston with respect to the present caliper.

FIG. 6 is a front view showing the same process as in FIG.

FIG. 7 is a cross-sectional view showing an assembled state of a piston with respect to the present caliper.

FIG. 8 is a partial cross-sectional view showing the shape of the piston according to the present invention.

9 is a cross-sectional view showing an assembled state of the piston shown in FIG. 8 with respect to a caliper.

FIG. 10 is a front view showing the structure of a conventional caliper.

FIG. 11 is a cross-sectional view showing a state in which a piston is attached to a conventional caliper.

FIG. 12 is a cross-sectional view showing an assembled state of a piston to a conventional caliper.

[Explanation of symbols]

 1 Caliper 2 Piston 2b Piston pad pressing surface 3 Bore 6 Cylinder part 7 Disk path part 8 Claw part 8a Claw part pad pressing surface 8b Recess forming surface 9 Recess 10 Opening 11 Carrier 14, 15 Pad 20 Relief surface 21 Claw part Tapered surface 22 Piston tapered surface D Disc

Claims (5)

[Claims] 1. A caliper composed of a cylinder portion, a disc path portion extending from the cylinder portion across a disc, and a pair of claw portions extending inward from a tip of the disc path portion in a radial direction of the disc. A pair of pads supported by the carrier is supported by a carrier fixed to a non-rotating portion of the vehicle so as to be floatable, and by a relative movement of the piston and the caliper housed in the bore of the cylinder portion. In the disc brake that presses against the disc,
A disc brake, wherein the width of the recess between the claw portions of the caliper is expanded on the tip side of the claw portions. 2. The disc brake according to claim 1, wherein the recess forming surface and the pad pressing surface of the claw portion of the caliper are connected by a tapered surface. 3. The caliper disk path portion is provided with an opening in the vicinity of the bore.
Disc brake described in. 4. The disc brake according to claim 1, wherein the periphery of the piston on the pad pressing surface side is a tapered surface. 5. A caliper comprising a cylinder part, a disk path part extending from the cylinder part across the disk, and a pair of claw parts extending inward from the tip of the disk path part in the radial direction of the disk. A pair of pads supported by the carrier is supported by a carrier fixed to a non-rotating portion of the vehicle so as to be floatable, and by a relative movement of the piston and the caliper housed in the bore of the cylinder portion. In the disc brake that presses against the disc,
A disc brake, wherein the peripheral edge of the piston on the pad pressing surface side is a tapered surface.