JPS6030857B2 - disc brake - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disc brake, and more particularly to reducing drag torque during non-braking.

A disc brake is a type of brake that is formed on both sides of a rotating disc and presses a pair of brake pads against the friction surfaces to suppress the rotation of the disc, and is widely used in vehicles and the like.

However, disc brakes have a serious drawback that they tend to cause a phenomenon called drag, in which the brake pad remains pressed against the friction surface of the disc with a constant force even when the brake is not applied. If drag occurs, the disk will rotate under constant drag torque, and the loss of energy will be irresistible. Particularly for vehicle brakes, it is even said that reducing drag torque during non-braking is the key to achieving low fuel consumption. This dragging also increases brake pad wear and shortens its lifespan, and can also cause brake overheating.

Overheating of the brakes reduces the coefficient of friction of the brake pads, making the brakes less effective. Therefore, great efforts have been made in the past to prevent this dragging phenomenon.

Unfortunately, however, there is still no known means to prevent drag that can be considered decisive. Based on this technical background, the present applicant first developed a disc that consists of a rotating disk with friction surfaces on both sides of its outer periphery, a friction material and a hair plate that holds it,
A pair of brake pads each having a torque transmitting surface on its hair plate, a torque receiving member provided in a fixed position and having a torque receiving surface in contact with the torque transmitting surface, and a back plate of the pair of brake pads. Equipped with functional aspects that support each,
In a disc brake including an actuator that presses the brake pad against the disc, the gap between the friction surface of the disc and the working surface of the actuator increases as you approach the center of gravity of the disc, and The torque transmitting surface of the brake pad and the torque receiving surface of the torque receiving material are moved in a direction away from the axis of the disc based on the torque acting on the brake pad during braking. A disc brake is filed that is sloped to generate force.

This patent application is currently pending as Tokugan Sho 54-42355. However, subsequent research revealed that there was room for further improvement. The present invention was developed in light of the above circumstances, with the purpose of providing an ideal disc brake that satisfies almost all of the required conditions.

In other words, it reduces drag torque when not braking,
SUMMARY OF THE INVENTION It is an object of the present invention to provide a disc brake that can prevent brake drag without increasing the amount of brake fluid required for braking, and that can be manufactured with the simplest possible structure and at a low cost. However, the gist of the present invention is to provide a rotating disk having friction surfaces on both sides of its outer circumference;
A pair of brake pads consisting of a friction material and a back plate for holding it, each having a torque transmitting surface on the hair plate, and a torque receiver disposed at a fixed position, the brake pad having a torque receiving surface in contact with the torque transmitting surface. and an actuator having at least one piston for pressing the pair of brake pads against the disc, wherein one of the pair of brake pads is pressed against the disc by the piston. , the back surface of the back plate is inclined so as to approach the friction surface of the disk as it goes toward the outer circumferential side of the disk to form a bare pad, and the torque transmission surface of the pinched pad and the corresponding At least a part of the torque-receiving surface is inclined so that a component force is generated that moves the acid-type pad toward the outer circumference of the disk based on the torque acting on the mechanical pad during braking, and A stopper means for defining the limit of the movement of the sliding pad and a spring means for biasing the rectangular pad toward the axis of the disk are provided, and the piston is moved so that the yoke of the piston is aligned with the inclination of the sliding pad. The working surface that is tilted perpendicularly to the curved back surface and supports the back surface of the piston drafting pad is made perpendicular to the axis of the piston.

In the disc brake according to the present invention, at the beginning of braking, when the sliding pad that is lightly pressed against the friction surface of the disc by the action of the actuator rotates with the disc, the axis of the disc is It is moved in a direction away from the center, and at that position it is fully pressed against the disc to perform a braking action.

When the brake is released, the brake pad is returned to a position close to the axis of the disc by the action of the spring member when the pressing force of the actuator is almost completely released. As a result, between the action surface of the actuator and the friction surface of the disc, there is a part thinner than each part of the sliding pad that existed between the two surfaces during braking, and almost A gap equal to the difference in thickness will be maintained between the disc friction surface, the rectangular pad and the actuator working surface.

Moreover, in the disc brake according to the present invention, when the rear surface of the brake pad is sloped to form a sliding pad, only the working surface of the piston that applies pressing force to the pad is not sloped to match the rear surface of the pad, but the piston and By tilting the axis of the cylinder perpendicular to the back surface of the pad, the working surface of the piston corresponds to the slope of the back surface of the pad. It can be made into a right angle, and is disclosed in Japanese Patent Application No. 54-42355 (Japanese Patent Application No. 55-1135).
It is no longer necessary to provide anti-rotation measures to the piston as in the disc brake disclosed in Publication No. 237).
The structure is simple and manufacturing costs can be reduced.

In a caliper-fixed disc brake that has pistons on both sides of the disc, it is desirable to take the above measures for the brake pads and pistons on both sides.

In addition, in a caliper floating type disc brake that has a piston on only one side of the disc, slanting the center of the piston is a problem only on one side, but making the brake pad in a valley shape means that it does not have a piston. It is also possible for the actuator reaction section side (caliper reaction section side).

In this case, the working surface of the reaction section is inclined to match the back surface of the bare pad, thereby making it possible to more completely prevent brake drag. EMBODIMENT OF THE INVENTION Hereinafter, in order to further clarify the purpose, structure, and effects of the present invention, embodiments thereof will be described in detail with reference to the drawings.

In FIGS. 1 to 3, 10 is a disk that rotates integrally with a wheel (not shown), and is provided with friction surfaces 11 and 12 perpendicular to the axis on both sides of its outer periphery.

A torque receiving section 20 is disposed in the vicinity of the disk 10 in a fixed position. This torque receiving member 2 consists of flat plate parts 21 and 22 arranged parallel to the friction surfaces 11 and 12 on both sides of the disc 10, and a pair of connecting parts 23 that connect the two parts beyond the outer circumference of the disc rotor 10. The flat plate portion 21 is fixed to a non-rotating member (not shown) such as an axle tube. A large closed opening extending from the flat plate part 21 to the flat plate part 22 via the connecting part 23 is formed in the center of the torque receiving member 20, and the inner pad 30, the outer pad 40, and the capacitor IJ pad 50 are accommodated within this opening. has been done.

As shown in FIGS. 4a and 4b, the inner pad 30' includes a back plate 32 having a substantially rectangular plate shape with the lower left and right corners cut out into triangular shapes, and a similar shape to the back plate. It consists of a friction material 31 fixed to it.

As a result, the back plate 32 is formed with a torque transmission surface 35 that is inclined so that the width increases toward the outer circumference of the disk, and a torque transmission surface 36 that has no substantial slope. Furthermore, although the thickness of the friction material 31 is uniform throughout, the back surface 34 of the back plate 32 is inclined ( The angle of inclination is 3 degrees). As a result, the inner pad 30 has a nuclear shape as a whole. In the notch formed in the flat plate part 21 of the torque receiving member 20, the disk 10 is also fitted with iron so that it can be slid and separated. That is,
As is clear from FIG. 2, the torque receiving member flat plate portion 21 has a torque receiving surface 2 which is inclined so that the width increases toward the outer circumferential side (upper side in FIG. 2) of the disk 10.
5 and a torque transmission surface 28 having no substantial inclination, the inner pad 30 has a spring 7 that allows the torque transmission surface 35 to be brought into close contact with the torque receiving surface 25, and the torque transmission surface 36 and Torque receiving surface 2
8 and between the lower surface 37 of the back plate and the bottom surface of the recess 29.
It is possible to falsify in a direction parallel to the axis of 0 (direction perpendicular to the plane of the paper in FIG. 2). The spring 7 has a leg portion 71 fixed to the torque receiving member connecting portion 23 and a caliper connecting portion 5.
It has a cross shape consisting of a head 73 that is in contact with the lower surface of the brake pad 3 and a pair of arm parts 72 that are supported by the shoulders of the brake pads 30 and 40.

The outer pad 40 has the same structure as the inner pad 30, and is housed and held in an opening formed in the flat plate portion 22 of the torque receiving member 20 in exactly the same manner as the inner pad 30.

In addition, a cylinder part 51 provided opposite to the back surface of the carrier IJ pad 5 river mainna pad 30, a fork-shaped glue action part (claw part) 52 provided opposite to the back surface of the outer pad 40, and the outer part of the disc 10 are provided. It consists of a connecting part 53 that connects the two beyond the periphery.

And this caliper 5 has a pair of slide pins 56 erected on the flat plate part 21 and protected by boots 58.
and a guide hole (not shown) formed in the arm portion 57, and is attached to the torque receiving member 20 so as to be able to move in the direction of the axis D of the disk 10. A piston 61 is connected to a piston seal 62 in the cylinder portion 51 of the caliper 50.
However, what should be noted here is that the axes of the cylinder portion 51 and the piston 61 are not parallel to the axis of the disk 10.

That is, the bottomed cylindrical cylinder portion 51 is open at the bottom side.
The axis DS is inclined so that it is higher than the outer circumferential side of the disk (towards the outer circumference of the disk), and a perpendicular line drawn between the axis DS and the friction surface 11 of the disk 10 (a straight line parallel to the rut center of the disk 10)
The angle 6 formed by T is 3 degrees. Therefore, the axis S' of the piston 61 that is slidably fitted to the cylinder portion 51 also forms an angle of 3 degrees with the perpendicular T. This angle of inclination is equal to that of the back surface 34 of the inner pad back plate 32. That is, the angle between the working surface 63 of the piston 61 and its axis S' is 90 degrees, and the piston 61 itself is no different from a normal piston. Further, the working surface 56 of the caliper action portion 52 is also an inclined surface inclined by 3 degrees from the vertical direction, corresponding to the back surface 44 of the outer pad back plate 42. In the disc brake configured as described above, in the non-braking state shown in FIGS. 1 to 3, the disc 10, the inner pad 30, and the outer pad 4
0, between the inner pad 30 and the piston 61, and between the upper pad 40 and the action portion 52.

In this state, when brake fluid is supplied to the cylinder portion 51 of the caliper 50, the piston 61 is pushed out and presses the inner pad 30 against the friction surface 11 of the disc 10.

The reaction force then moves the caliper 50 to the left in FIG. 3, and as a result, the reaction portion 52 presses the outer pad 40 against the friction surface 12 of the disk 10. In this way, the friction surfaces 11 and 1 of the disk 10
2, the brake pads 30 and 401 are subjected to a co-rotating torque that causes them to rotate together with the discs 10. Here, assuming that the disc 10 is rotating clockwise in FIG. 2, a co-rotating force in the same direction acts on both brake pads 30 and 401. This situation applies to both brake pads.
Since the problems are the same, the three inner pads will be explained below. When the rotation torque in the above direction acts on the inner pad 301, the torque transmission surface 35 on the right side in FIG. 2 (left side in FIG. 4a) is pressed against the torque receiving surface 25 of the flat plate part 21.

As a result, a reaction force acts on the torque transmission surface 35 from the torque receiving surface 25, but this reaction force is applied to the inner pad 30.
A component of force in the direction of moving the pad toward the outer circumference of the disk 10 (upward in FIG. 2) (hereinafter, this component of force will be referred to as "pad pushing force")
). Therefore, the inner pad 30 is moved toward the outer circumferential side of the disk by this pad pushing force, and during this movement, the inner pad 3 is moved by the inclined torque transmission surface 3 on the side near the axis of the disk 10.
5 is in contact with the flat plate part 21, but
It has been confirmed through experiments that it is guided by the torque receiving surface 35 and moves toward the outer circumference of the disk 10 without any trouble (
(Illustrated by the two-dot chain line in Figure 2). In addition, during this movement, the inner pad 301 is connected to the hair plate back surface 34 and the piston action surface 63.
and the frictional force between the torque transmitting surface 35 and the torque receiving surface 25, as well as the component force in the direction toward the axis of the disk 10 of the pressing force applied from the piston action surface 63 to the back plate rear surface 34. , the spring force of the spring 70, and the weight of the inner pad 30 itself act as a drag force, but the torque is set so that a pad pushing force sufficient to overcome this drag force and move the inner pad 30 diagonally upward to the right is obtained. Inclination angle 02 of transmission surface 35 and torque receiving surface 25
has been selected.

The inner pad 30 is stopped at a position farthest from the axis of the disk 10 by the torque transmitting surface 36 assisting the torque receiving surface 28. That is, the torque receiving surface 28 that is not substantially inclined is the inner pad 3
It also serves as a stopper means for preventing the 0 from moving beyond a certain level towards the outer periphery of the disk. This direction of movement is the direction in which a mimetic action occurs between the back plate rear surface 34 and the piston action surface 63, and as a result, the friction material 31 of the inner pad 30
is pressed against the friction surface 11 of the disk 10 with a strong force. At the same time, the outer pad 40 is also moved in the same manner as shown in FIG. 5, away from the center of the disk 10.

When the disk 10 is moved a certain amount toward the outer circumference, both the inner pad 30 and the outer pad 40 are completely prevented from rotating together by the torque-receiving material 201, so that the braking fluid pressure in the cylinder portion 51 is A known braking action is performed as the value increases.

At this time, the brake pads 30 and 40 are vertically deformed, and the cap IJ pad 50 is deformed to expand so that the cylinder portion 51 and the IJ action portion 52 move away from each other.

On the other hand, when the brake is released, as the braking fluid pressure in the cylinder section 51 is lowered, the pressing force by the piston 61 is lowered, and the brake pads 30 and 40 are compressively deformed and the caliper 50 is expanded. Elastic deformations such as open deformation are recovered.

When this elastic deformation has almost completely recovered, the inner pad 30
The outer pad 40 is pushed back to the original position closest to the ball 10 of the disk 10 by the elastic force of the spring 70. By this movement, the back surface 3 of the inner pad back plate 31
4 and the piston action surface 63, as well as between the back surface 44 of the outer pad back plate 42 and the IJ action part action surface 56 (see FIG. 3). The pressing force on 40 is completely released. Furthermore, this gap is eliminated when the brake pads 30 and 40 are moved again to the position farthest from the center of the disc 10 during the next braking. There is no risk of an increase in the amount of fluid consumed by the piston 61, but rather the amount of oil consumed is reduced by the amount that shakeback or knockback of the piston 61 is reduced compared to conventional disc brakes. Additionally, since the brake pads 30 and 40 are moved against the frictional force between their contact surfaces, the coefficient of friction between their contact surfaces should be as small as possible to ensure smooth operation. It is desirable to keep it. To achieve this, the surface roughness of each contact surface should be reduced as much as possible, and at least one of the contact surfaces should be fixed with a stainless steel plate or hard chrome plated to increase the coefficient of friction due to rust. It is advantageous to prevent this. In the disc brake according to the present invention, as described above, the brake pads 30 and 40 are bare pads with an inclined surface on the back side, and the piston action surface 63 and the reaction part action surface 56
is the corresponding slope. Therefore, when the piston 61 is moved parallel to the axis of the disk in the same way as in a conventional disc brake, its working surface 63 is moved parallel to the axis S.
In order to ensure that this inclined working surface 63 comes into contact with the back plate rear surface 34, some kind of rotation prevention means is indispensable. However, in the above embodiment, the axis D of the cylinder part 51 itself is inclined, and the piston 61 itself is completely the same as the conventional one, so even if the piston 61 rotates, no problem occurs, and the rotation prevention means There is no longer a need for Furthermore, the axis of the cylinder 51 is only slightly inclined, and there is no difference at all from the conventional cylinder in terms of its shape, structure, and other essential aspects. It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that changes and improvements can be made as appropriate without departing from the spirit thereof.

For example, in the embodiment described above, the drag prevention effect is obtained not only when the vehicle is moving forward but also when it is moving backward.
Both the torque transmitting surface and the torque receiving surface on both sides of the pad were tilted, but if the effect of preventing dragging can be achieved when the vehicle moves forward, the purpose can be almost achieved. It is also possible to incline only the torque transmitting surface and the torque receiving surface. In addition, the torque transmission surface and the torque receiving surface are not partially sloped as in the previous embodiment, but are entirely sloped, and movement of the brake pad beyond a certain level toward the outer circumference of the disk is regulated by a dedicated stopper surface. It is also possible to do so.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the present invention, and Fig. 2 is a plan view showing an embodiment of the present invention.
The cross-sectional view of Rollo in the figure, Figure 3 is m-- in Figure 1.
4a and b are respectively a front view and a side view of the inner pad used in the embodiment shown in FIGS. 1 to 3, and FIG. 5 is an end view of the inner pad shown in FIGS. FIG. 4 is an explanatory diagram of the operation of the embodiment. 10... Disc, 11, 12... Friction surface, 20... Torque receiving section village, 25, 28... Torque receiving surface, 30... Inner pad, 31・・・
・Friction material, 32. ．． …． Back plate, 34... Back,
35, 36... ...Torque transmission surface, 40...
・Outer pad, 50... ...Caliper, 51...
Cylinder part, 52... Reaction part, 56...
- Action surface of reaction part, 61... Piston, 63... Piston action surface, 70...
spring. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1 A rotating disk with friction surfaces on both sides of the outer circumference,
A pair of brake pads consisting of a friction material and a back plate for holding it, the back plate having a torque transmitting surface, and a torque receiving member provided with a torque receiving surface that comes into contact with the torque transmitting surface and arranged in a fixed position. and an actuator having at least one piston for pressing the pair of brake pads against the disk, wherein one of the pair of brake pads that is pressed against the disk by the piston is mounted on a back plate thereof. The back surface is inclined toward the outer circumferential side of the disk so as to approach the friction surface of the disk to form a wedge-shaped pad, and at least one of the torque transmitting surface and the corresponding torque receiving surface of the wedge-shaped pad is formed. The portion is inclined so as to generate a force that moves the wedge-shaped pad toward the outer circumference of the disk based on the drag torque acting on the wedge-shaped pad during braking, and the limit of the movement of the wedge-shaped pad is set. and a spring means for biasing the wedge-shaped pad toward the axis of the disk, and tilting the piston so that its axis is perpendicular to the inclined back surface of the wedge-shaped pad. A disc brake characterized in that the working surface that contacts the back surface of the wedge-shaped pad of the piston is perpendicular to the axis of the piston.