JPH0313632Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a structure of a disc brake used in an automobile, and particularly to a structure designed to reduce brake noise.

(Prior art) In general, a disc brake has a pair of inner and outer pads arranged on both the inner and outer sides of a disc rotor that rotates with the wheels, and when braking, both pads are pressed against the disc rotor by the action of a caliper, so that the friction force is used. The rotation of the disc rotor or wheel is suppressed,
In this type of disc brake, harsh brake noise may occur during braking.

One of the causes of this brake noise is vibration of the disc rotor and pads, or resonance between the two. In other words, the disc rotor tends to swing at the outer periphery that is farthest from the central support, and this swing is suppressed by being pressed from both sides by a pair of pads during braking. During braking, the pressing force is insufficient, especially on the trailing side of the pad, so that the vibration of the outer circumference of the rotor is not sufficiently suppressed.
Also, on the pad side, during light braking, insufficient pressing force is applied to the trailing side part, so the trailing side part vibrates, and this vibration is combined with the vibration of the outer circumferential part of the disc rotor. It generates noise.

Here, the reason why the pressing force is insufficient on the trailing side portion of the brake pad during light braking is considered to be due to the following reasons. That is, when a disc rotor A is pressed from both sides by a pair of pads B and B, as shown in FIG. The trailing side ends of the back metals C, C, that is, the ends C' that are forward in the rotational direction a of the rotor A,
Since this receiving portion is located away from the surface on which the frictional forces F and F act, moments M and M in the directions shown are applied based on the frictional forces F and F. These moments M, M act to press the leading side parts B', B' of the pads B, B against the rotor A, and the trailing side parts B'', B'' are pushed from the rotor A. It acts to separate them. In this way, it is thought that the pressing force of the pads B, B is insufficient at the trailing side portions B'', B''.

By the way, according to Japanese Patent Application Laid-open No. 55-132423,
An invention has been disclosed in which the occurrence of brake noise is prevented by improving the operating state of the pressing force on the pads. As shown in Fig. 10, the annular part on the back surface of the back metal C of the pad B, which is pressed by the piston, is divided at the center by 45° inclined lines X-X, Y-Y, and the pad B is By making the upper and lower parts C″ and C″ located in the width direction slightly protrude from the left and right parts C and C located in the length direction, the upper and lower parts indicated by diagonal lines are created.
The pressing force is concentrated on C″ and C″. According to this, rocking around the diametrical axis of the disc rotor is allowed, and rocking around the circumferential axis of the disc rotor is suppressed, so that the friction surface of the pad B is It adapts to the unevenness caused by the rotation of the disc rotor, thereby preventing the generation of brake noise during braking.
However, even with this invention, the problem of insufficient pressing force on the trailing side portion of the pad during light braking cannot be solved, and the generation of brake noise caused by this problem cannot be prevented.

(Purpose of the invention) In view of the above-mentioned circumstances, the present invention aims to prevent or reduce the problem of brake noise in disc brakes, especially the brake noise caused by insufficient pressing force on the trailing side of the pad during light braking. Another object of the present invention is to generate a required braking force during heavy braking.

(Structure of the invention) In order to achieve the above object, the present invention is characterized by the following structure.

That is, in a disc brake that suppresses the rotation of a disc rotor that rotates with the wheel by pressing the disc rotor with a piston via an inner pad or an outer pad, during light braking, the pressing force of the piston is applied to at least one of the inner pad and the outer pad. The force is transmitted to one of the inner pad and the outer pad through a biasing member that causes the front side of the pad to protrude toward the disc rotor in the forward rotational direction of the disc rotor compared to other parts, and during heavy braking, the force is transmitted to the piston. The pressing force is directly transmitted to at least one of the inner pad and the outer pad. The biasing member is composed of, for example, a leaf spring provided on the back metal of the pad, and is interposed between the pad and the piston of the caliper, and is directed against the forward rotational direction of the disc rotor in the pad during light braking. and press the front part against the disc rotor. As a result, during light braking, the trailing side portion of the pad is pressed against the disc rotor by the pressing force of the piston and the pressing force of the biasing member, and the lack of pressing force in this portion is resolved, and the pad is Vibration is prevented. Furthermore, the vibration of the outer peripheral portion of the disc rotor is effectively suppressed by the pressing force of the urging member, thereby preventing or reducing the occurrence of brake noise during light braking. Furthermore, during heavy braking, the pressing force of the piston is directly transmitted to at least one of the inner pad and the outer pad, and as a result, a large pressing force acts on the disc rotor through the entire inner pad or outer pad. As a result, the necessary braking force required during heavy braking can be generated.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

As shown in Figures 1 and 2, the disc brake 1
0 includes a disc rotor 11 connected via a wheel hub 3 to an axle 2 that rotates integrally with the wheel 1;
It is composed of a pair of inner pads 12 and outer pads 13, which are arranged in corresponding positions on both the inner and outer sides of the disc rotor 11, and a caliper 14. This caliper 14 is attached to a knuckle 5 which is connected to the lower end of the strut 4 and pivotally supports the axle 2.
Supported via book slide pins 15, 15,
The inner pad 1 is slidable in the axial direction of the axle 2 or the disc rotor 11.
The outer pad 13 has a piston 16 facing the back surface of the outer pad 13, and an arm 17 located on the back of the outer pad 13, straddling the disk rotor 11. In addition, inner pad 1
2 and the outer pad 13, respectively, friction materials 18, 19 that are in contact with both sides of the disc rotor 11, and back metals 20, 2 that hold the friction materials 18, 19 from the back side.
1, and engaging portions 20a, 20a, 21 provided at both ends of the back metals 20, 21.
a, 21a are engaged with support portions 5a, 5a formed on the knuckle 5, and are supported so as to be slidable in the axial direction of the disk rotor 11.

Of the pads 12 and 13, the back side of the back metal 20 in the inner pad 12 has a third,
As shown in FIG. 4, biasing members 22 and 23 are attached. The biasing members 22 and 23 are each made by bending a band-shaped leaf spring so that the central part is triple-folded, and one end is a common fastening member in the groove 20b formed on the back surface of the back plate 20. 24, the said back money 2
0, and the other end is fixed to the fixing member 2.
The flexible parts 22a and 23 are fixed to both ends of the back metal 20 by 5 and 25, respectively, and are folded over each other.
a protrudes outward from the inside of the groove 20b.
Here, the biasing members 22 and 23 are attached to the pad 12.
, that is, at a position corresponding to the outermost peripheral portion of the disk rotor 11, and the flexible portions 22a, 2
3a is positioned so as to be pressed by the annular piston 16, and the biasing member 22 is located on the front side, that is, on the trailing side A with respect to the rotational direction a when the disc rotor 11 moves forward, and the biasing member 22 is positioned so as to be pressed by the annular piston 16. The plate thickness is increased by the biasing member 23 located at , and the rigidity or spring constant is increased.

Next, the operation of the above embodiment will be explained. When braking hydraulic pressure is supplied to the caliper 14 during braking, the piston 16 of the caliper 14 protrudes and presses the inner pad 12 against the inner surface of the disc rotor 11, and the caliper 14 itself slides inward due to the reaction force. The arm portion 17 of the caliper 14 that straddles the disc rotor 11 presses the outer pad 13 against the outer surface of the disc rotor 11. As a result, the disc rotor 11 is clamped and pressed from both sides by the pair of pads 12 and 13, and the rotation of the disc rotor 11 or the wheel 1 is suppressed by the frictional force.

However, during light braking when the pressing force of the pads 12, 13 is relatively small, conventionally, the pressing force of the trailing side portions of both pads 12, 13 is insufficient, so that the trailing side portions of the pads 12, 13 are In addition to the vibration, the vibration at the outer circumferential portion of the disc rotor 11 was not effectively suppressed, resulting in brake noise. However, in this embodiment, the inner pad 12
The biasing members 22 and 23 are attached to the back surface of the backing plate 20, and the inner pad 12 is pressed by the piston 16 via the biasing members 22 and 23 during braking, so the biasing member 22 with a particularly large spring constant is attached. On the trailing side, the pad 12 is also pressed against the disk rotor 11 by the urging force of the urging member 22. This solves the problem of insufficient pressing force on the trailing side during light braking.
Vibrations on the trailing side of the pad 12 are prevented, and since the pressing force of the biasing member 22 acts on the outer circumference of the disk rotor 11 where the deflection is greatest, the deflection of the outer circumference of the rotor is also suppressed. This will prevent brake noise from occurring. Here, the pressing force by the biasing member 22 acts on the caliper 14 as a reaction force, and the caliper 14
4 to the outer pad 13. Therefore, the lack of pressing force on the trailing side portion of the outer pad 13 is also resolved. Further, the biasing members 22 and 23 are completely compressed during heavy braking where a large pressing force is applied, or are completely pushed into the groove 20b of the back metal 20, so that the pressing force by the piston 16 is directly transmitted to the pad 12. As a result, a large pressing force is applied to the disc rotor 11 through the entire pad 12, and the required braking force required during heavy braking can be generated.

Of the biasing members 22 and 23, the biasing member 2 with a small spring constant is attached to the leading side.
3 may be omitted. Further, the urging member is not limited to the shape shown in FIGS. 3 and 4, but may be of the shape shown in FIGS. 5 to 8, respectively. These biasing members 31 to 34 are all located at predetermined positions on the back surface of the back metal 20, that is, positions corresponding to the outer circumference of the disc rotor and on the trailing side with respect to the rotational direction when the disc rotor moves forward. , is installed in a recess 20c provided at a position to be pressed by the piston, and a part is fixed in the recess 20c, and the other part protrudes from the recess 20c, so that the piston does not touch the piston during light braking. It's starting to feel like pressure.

Further, in the above embodiment, the biasing member is provided on the inner pad side, but the same effect can be obtained even if it is provided on the outer pad side, and if necessary, it may be provided on both the inner pad and the outer pad. It's okay.

(Effects of the invention) As described above, according to the invention, in a disc brake in which a pair of pads presses the disc rotor from both the inside and outside sides during braking, the pressing force of the trailing side portion of the pads during light braking is This solves the problem of insufficient water and effectively suppresses the runout of the outer periphery of the disc rotor. This reduces the occurrence of brake noise caused by vibration of the pads and vibration of the outer peripheral portion of the disc rotor during light braking.
Furthermore, during heavy braking, a large pressing force acts on the disc rotor through the entire inner pad or outer pad, making it possible to generate the required braking force required during heavy braking.

[Brief explanation of the drawing]

Figures 1 to 4 show the first embodiment of the present invention. Figure 1 is a view of the disc brake from inside the vehicle body, Figure 2 is a sectional view taken along the line - Figure 1, FIG. 4 is a rear view and a plan view of the pad in the disc brake. Figures 5 to 8 show the second to fifth embodiments of the present invention, respectively. Figures 5a to 8a are rear views of the main parts of the pads in each embodiment, and Figures 5b to 8a are rear views of the main parts of the pads in each embodiment. b are respectively shown in Figures 5a to 8.
It is a sectional view cut along the - line to - line in Figure a. FIG. 9 is a plan view of the main parts of a disc brake, illustrating the problems that the present invention attempts to solve;
FIG. 10 is a rear view of a pad showing a conventional example. 11... Disc rotor, 12... Inner pad, 13... Outer pad, 22, 31-34...
...Biasing member.

Claims (1)

[Scope of utility model registration request] In a disc brake that suppresses the rotation of a disc rotor that rotates with the wheel by pressing the disc rotor with a piston via an inner pad or an outer pad, during light braking, the pressing force of the piston is applied to at least one of the inner pad and the outer pad. The force is transmitted to one of the inner pad and the outer pad through a biasing member that causes the front part of the disc rotor to protrude toward the disc rotor in comparison to other parts, and during heavy braking, the force of the piston is transmitted. A disc brake structure characterized in that pressing force is directly transmitted to at least one of an inner pad and an outer pad.