JP2003184917A - Floating caliper type disc brake - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize light structure capable of providing enough brake force and enough durability at low cost. <P>SOLUTION: A caliper 2b comprises a light alloy main portion 17, and a metallic-plate made reinforcing plates 14a, 14b with more excellent heat resistance than that of the light alloy. A covering plate portion 18 of the reinforcing plates 14a, 14b covers an internal peripheral side face of a connection 13 and inside surfaces of caliper claws 9b, 9b that are opposed against a rotor heated to high temperature at the time of brake action. Through this structure, the light alloy main portion 17 with comparatively low rigidity is reinforced and temperature rise of the main portion 17 is suppressed at brake action, thus attaining the above purpose. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The floating caliper type disc brake according to the present invention is used for braking an automobile. The present invention is intended to reduce the weight of the disc brake while suppressing the cost increase. is there.

[0002]

2. Description of the Related Art Conventionally, a disc brake having a structure as shown in FIGS. 7 to 8 has been used as a disc brake for braking an automobile. The disk brake shown in FIGS. 7 to 8 is of a type called a floating caliper type, which displaces the caliper 2 with respect to the rotor 1 during braking, and is described in JP-A-55-123029.
In this floating caliper type disc brake, a support 3 provided adjacent to one side of a rotor 1 that rotates with wheels (not shown) is attached to a vehicle body by using mounting holes 4 and 4 provided at a lower portion of the support 3. (Not shown). The caliper 2 is supported on the support 3 so as to be displaceable in the axial direction of the rotor 1. Further, a part of the support 3 is provided with a pair of front and rear engaging portions 5 and 6 on the inflow side and the outflow side at positions separated from each other in the circumferential direction of the rotor 1. Each of the engaging portions 5 and 6 has a tip bent in a U-shape so as to straddle the outer peripheral portion of the rotor 1 in the vertical direction of FIG. 7, and the engaging portions 5 and 6 have pads 7 and 7, respectively. Both ends of the rotor are engaged with each other so as to be slidable in the axial direction of the rotor 1. Further, the caliper 2 having the cylinder portion 8 and the caliper claws 9 is arranged so as to straddle the pads 7, 7, and the cylinder portion 8 is provided with an inner side (width in an assembled state on a vehicle). (The side closer to the center in the direction, the lower side of FIG. 7)
1 that presses the pad 7 of
It contains 0.

For braking, the cylinder portion 8 is used.
Pressure oil is fed into the inside, and the inner pad 7 is pressed against the inner surface of the rotor 1 by the piston 10 from the bottom to the top in FIG. 7. Then, as a reaction of this pressing force, the caliper 2 is displaced downward in FIG. 7, and the caliper claw 9 is located on the outer side (the side that is outward in the width direction in the state of being assembled to the vehicle, the upper side in FIG. 7). ) Pad 7
It is pressed against the outer surface of the rotor 1. As a result, the rotor 1 is strongly clamped from both inner and outer side surfaces, and braking is performed.

With respect to the circumferential direction of the rotor 1, a constriction 11 is formed at the center of the caliper pawl 9 to form the caliper pawl 9 in a bifurcated shape. The reason for this is
This is because a tool can be inserted into the cylinder portion 8 when finishing the inner peripheral surface of the cylinder portion 8.
That is, in order to make the caliper 2, conventionally, a material having a general shape is made by casting iron, and then finishing work such as cutting is performed at a necessary portion. The cylinder part 8
With regard to the above, the inner diameter is machined to a desired dimension by cutting to finish the inner peripheral surface smooth. The constricted portion 11 is formed so that a tool for such cutting can be inserted into the cylinder portion 8.

As described above, in the case of a disc brake which has been generally practiced in the past, the caliper 2 was made of cast iron, but the weight of the portion existing closer to the wheel than the spring constituting the suspension system is large. In order to reduce certain so-called unsprung load and improve various performances such as fuel consumption performance, traveling performance, and riding comfort performance, it has been studied to use caliper made of light alloy such as aluminum alloy and magnesium alloy. A technique described in Japanese Patent Application Laid-Open No. 7-174169 has been conventionally known as a technique for making the caliper from such a light alloy. In the conventional technique described in this publication, as shown in FIG. 9, a reinforcing member 12 is provided inside a caliper 2a made of an aluminum alloy.
By casting around, the caliper 2a is designed to be both lightweight and rigid.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The one described in Japanese Patent No. 74169 is considered to be difficult to manufacture because it is difficult to position the reinforcing material 12 inside the mold. Moreover, since the entire surface of the caliper 2a is covered with the light alloy, it is difficult to ensure sufficient heat resistance. That is, the rotor 1 (see FIGS. 7 to 8) that constitutes the disc brake may increase in temperature to the extent of red heat under severe operating conditions such as rapid braking repeated during mountainous traveling. In such a case, the surface of the caliper 2a made of a light alloy, which has a lower melting point than that of cast iron, may be softened. When braking is performed by the caliper 2a having a softened surface, it is conceivable that plastic deformation occurs on a surface that strongly abuts the back surface of the pad, such as the inner surface of the caliper claw 9a, resulting in uneven wear of the pad. The floating caliper type disc brake of the present invention has been invented in order to eliminate such inconvenience.

[0007]

The floating caliper type disc brake of the present invention includes a support, a pair of pads, a caliper, and a piston, as in the previously known floating caliper type disc brake. Equipped with. The support is fixed to the vehicle body adjacent to the rotor that rotates with the wheels. Also, the above 1
The pair of pads are arranged on the inner side and the outer side of the rotor. The caliper is formed by connecting a cylinder part provided on the inner side and a caliper claw provided on the outer side by a connecting part existing radially outward of the outer peripheral edge of the rotor and supported by the support. The lever can be displaced in the axial direction. Further, the piston is fitted in the cylinder portion. When the piston is pushed out, the pair of pads is pressed against both side surfaces of the rotor by the piston and the caliper claw to perform braking.

In particular, in the floating caliper type disc brake of the present invention, the caliper includes a main part made of a light alloy and a reinforcing plate having a heat resistance higher than that of the light alloy. The reinforcing plate covers at least a part of the main portion of the side surface of the caliper pawl facing the rotor and the surface of the connecting portion facing the rotor.

[0009]

In the floating caliper type disc brake of the present invention constructed as described above, the main part is cast because the reinforcing plate is provided so as to be exposed on the surfaces of the caliper pawls and the connecting parts facing the rotor. Therefore, the reinforcing plate can be easily positioned in the mold. Further, since the side surface of the caliper claw that presses the back surface of the pad on the outer side is covered with the reinforcing plate, it is not necessary to machine this side surface for finishing. Further, by appropriately selecting the material and shape of the reinforcing plate, it is possible to secure sufficient strength and rigidity without using a material having a large volume. As a result, a sufficient weight reduction can be achieved without making the manufacturing work troublesome. Therefore, the floating caliper type disc brake capable of sufficiently reducing the unsprung load can be realized at low cost. Also, it faces the rotor whose temperature rises during braking,
Since the surface of the caliper claw and the connecting portion is covered with the reinforcing plate having excellent heat resistance, the strength of the main part made of the light alloy constituting the caliper is high even when the temperature of the rotor is particularly increased. It can be prevented from lowering and sufficient braking force and durability can be secured.

[0010]

1 to 5 show an example of an embodiment of the present invention. The feature of the present invention is that the caliper 2
By devising the structure of b, the point is to realize a disc brake that is lightweight and exhibits sufficient performance at low cost. When the caliper 2b is assembled to the support to form a disc brake and further braking is performed, the configuration and operation are the same as in the case of the conventional structure shown in FIGS. Therefore, the following description will be focused on the structure of the caliper 2b portion, which is a feature of the present invention.

The caliper 2b includes a cylinder portion 8a provided on the inner side (upper right side in FIG. 1, right side in FIG. 2) and a caliper claw 9 provided on the outer side (lower left side in FIG. 1, left side in FIG. 2).
b and 9b are connected by a connecting portion 13 existing radially outward of the outer peripheral edge of the rotor 1 (see FIGS. 7 to 8).
Such a caliper 2b has a pair of reinforcing plates 14 to be described later.
The axial displacement of the rotor 1 with respect to the support 3 (see FIGS. 7 to 8) by the pair of guide pins 16 and 16 supporting the respective base end portions of the mounting portions 15 provided on a part of a and 14b. Can be supported. A piston 10 (see FIGS. 7 to 8) is fitted in the cylinder portion 8a, and braking is performed as the piston 10 is pushed out based on the pressure oil fed into the cylinder portion 8a.

The caliper 2b has a main portion 17 made of a light alloy such as an aluminum alloy and a pair of the reinforcing plates 14a and 1a.
It consists of casting 4b. Each of these reinforcing plates 14a, 14b
Each of them is formed by bending a metal plate material such as a steel plate, a stainless steel plate, or the like, which has characteristics superior to light alloys at least in terms of heat resistance. The one reinforcing plate 14a and the other reinforcing plate 14b have mutually symmetrical shapes. That is, each of the reinforcing plates 14a and 14b is
A cover plate part 18 bent in a letter shape and an insert part 19 protruding from the inner side end part of the cover plate part 18 toward the inner side.
And the mounting portion 15 which is also bent in the circumferential direction.

The cover plate portion 18 is composed of a main plate portion 20 and a side plate portion 21. The cover plate portion 18 is L-shaped as a whole and also has an L-shaped cross section. Then, the both plate portions 2
The main plate portion 20 of 0 and 21 covers the inner peripheral side surface of the connecting portion 13 and the inner side surface of the caliper claw 9b, and the side plate portion 2
Reference numeral 1 covers circumferential side surfaces of the connecting portion 13 and the caliper claw 9b. Further, the insert portion 19 is a part of the cylinder portion 8a that constitutes the main portion 17, and the main portion 17 is provided in an outer portion of a cylinder hole 22 for fitting a piston in the radial direction of the rotor 1. Inserted during casting.

Further, the mounting portion 15 has the side plate portion 21.
Is bent at a right angle in the circumferential direction from the inner end of the guide pin 16, and a mounting hole 23 for coupling and supporting the base end of the guide pin 16 is formed at the tip end. A reinforcing rib 2 formed by plastically deforming the plate material in the surface direction is provided at the base end of the mounting portion 15.
4 is provided. The base end portion of the mounting portion 15 is inserted into the main portion 17 such that the base half portion of the reinforcing rib 24 enters the main portion 17 when the main portion 17 is cast. The pair of reinforcing plates 14a and 14b, which have symmetrical shapes with each other, are combined with the main portion 17 in a state of sandwiching the main portion 17 from both sides in the circumferential direction. In this state, the pair of mounting portions 15 and 15 are projected from both side surfaces of the main portion 17 in the circumferential direction.

As described above, the main portion 17 and the reinforcing plates 14a, 1
In the caliper 2b which constitutes the floating caliper type disc brake of the present invention composed of 4b and 4b, the reinforcing plates 14a and 14b are provided in the main portion 17, and the cover plate portion 18 is provided.
Are inside surfaces of the caliper claws 9b, 9b and the connecting portion 1
In the state of being exposed on the inner peripheral side surface of 3, the main portion 17 is cast during casting. At the time of this casting work, the above-mentioned reinforcing plates 1
4a and 14b are set at predetermined positions in the cavity of the casting mold, and the set position is the end of this cavity. That is, unlike the conventional structure shown in FIG. 9, the reinforcing member 12 is not entirely embedded in the caliper 2a. Therefore, each of the reinforcing members in the cavity of the mold for casting the main portion 17 is reinforced. The plates 14a and 14b can be easily positioned. Therefore, compared with the conventional structure shown in FIG. 9,
Manufacturing work is facilitated and cost can be reduced.

Further, the back surface of the pad on the outer side is pressed,
The inner surfaces of the caliper claws 9b, 9b are the reinforcing plates 1
Since it is covered by the front half portion 25 of the main plate portion 20 which constitutes 4a and 14b, it is not necessary to machine the inner side surface for finishing. Moreover, each of the reinforcing plates 14a and 14b is
By properly selecting the material and shape, sufficient strength and rigidity can be secured without using a material having a large volume. Particularly, in the illustrated example, since the cover plate portion 18 provided along the connecting portion 13 and the caliper claw 9b has an L-shaped cross section, the cover plate portion 18 and the connecting portion to which the cover plate portion 18 is attached are attached. 13 and caliper claw 9b (these connecting portions 1
3 and the caliper claw 9b (including the continuous portion) can be sufficiently secured in bending rigidity. As a result, the weight can be sufficiently reduced without making the manufacturing work troublesome. Therefore, the floating caliper type disc brake capable of sufficiently reducing the unsprung load can be realized at low cost.

The inner side surfaces of the caliper pawls 9b, 9b and the inner peripheral side surface of the connecting portion 13 facing the rotor whose temperature rises during braking are the main plates of the reinforcing plates 14a, 14b having excellent heat resistance. It is covered by the part 20. Since the main plate portion 20 functions as a heat shield plate, even if the temperature of the rotor is particularly increased, the temperature rise of the main portion 17 made of the light alloy constituting the caliper 2b is suppressed, and the main portion 1 is prevented.
It is possible to prevent the strength of No. 7 from decreasing and to secure sufficient braking force and durability. In addition, in FIG.
Although the structure in which the pair of reinforcing plates 14a and 14b are encircled is shown, a structure in which an integral (single) reinforcing plate 14 is encircled may be adopted as shown in FIG.

[0018]

Since the present invention is constructed and operates as described above, a floating caliper type disc brake having a sufficient durability, a lightweight and a sufficient braking force while suppressing a cost increase is provided. realizable.

[Brief description of drawings]

FIG. 1 is a perspective view of a caliper showing an example of an embodiment of the present invention.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a view of the reinforcing plate taken out and viewed from the same direction as FIG.

FIG. 4 is a view seen from above in FIG.

FIG. 5 is a diagram viewed from the right side of FIG.

FIG. 6 is a perspective view similar to FIG. 1, showing another example of the embodiment.

FIG. 7 is a partial cross-sectional view showing an example of a conventional structure as viewed from the outside in the radial direction.

8 is a sectional view taken along line BB of FIG.

FIG. 9 is a perspective view showing an example of a conventional structure in which a caliper is made of a light alloy.

[Explanation of symbols]

1 rotor 2, 2a, 2b caliper 3 support 4 mounting holes 5 times entry side engaging part 6 Outgoing side engaging part 7 pads Cylinder part 9, 9a, 9b caliper claw 10 pistons 11 constriction 12 Reinforcement material 13 Connection 14, 14a, 14b Reinforcing plate 15 Mounting part 16 guide pins 17 main body 18 Cover plate part 19 Insert part 20 Main plate 21 Side plate 22 Cylinder hole 23 mounting holes 24 Reinforcing rib 25 first half

Claims (2)

[Claims] 1. A support fixed to a vehicle body adjacent to a rotor that rotates together with a wheel, a pair of pads arranged on an inner side and an outer side of the rotor, a cylinder portion and an outer provided on the inner side. A caliper pawl provided on the side of the rotor, the caliper being supported by the support and displaceable in the axial direction of the rotor, and the cylinder. In a floating caliper type disc brake, which comprises a piston fitted in the interior of the rotor, and the piston and the caliper claw press the pair of pads against both side surfaces of the rotor as the piston is pushed out. The caliper includes a main part made of a light alloy and a reinforcing plate having heat resistance higher than that of the light alloy, and at least one part of the main part is provided by the reinforcing plate. A floating caliper type disc brake, wherein a portion covers a side surface of the caliper pawl facing the rotor and a surface of the connecting portion facing the rotor. 2. The caliper claws and the connecting portions are circumferentially opposite side surfaces of the rotor covered by the reinforcing plate.
The floating caliper type disc brake according to claim 1.