JPH01108426A - Vehicle braking device - Google Patents

Abstract

PURPOSE:To suppress unpleasant dragging sound and to prevent a pad from being worn, by providing a resilient material spring which urges a slidably supported caliper in the pressing direction of a piston. CONSTITUTION:A caliper 17 is laid striding a disc rotor 10 and pads 12, 13. A stopper 20 is positioned by a nut 21 so as to regulate the movable range of the caliper 17 to a value equal to a clearance alpha between the disc rotor 10 and the outer pad 13. A spring 22 is disposed between the stopper 20 and a boss section 17a of the caliper 17 which is therefore urged in the pressing direction of the piston 19. Thus, a dragging phenomenon is eliminated so as to suppress unpleasant dragging sound and to prevent the pads from being worn due to the dragging phenomenon.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) This invention brakes a wheel by press-contacting pad members from both sides of a disc rotor that is integrally attached to an axle and rotates together with the wheel. This relates to a vehicle braking device (disc brake).

(Prior Art) A type called a disc brake is often used as a braking device for vehicles.

In this disc brake, a disc rotor consisting of a single disc is attached concentrically to the axle and rotates with the axle. Both sides of the disc rotor serve as friction surfaces, and the disc rotor can be moved in a direction perpendicular to the friction surfaces. A pad and a pressing means for pressing the pad against the friction surface of the disc rotor from both sides using hydraulic pressure are provided, and this pressing means is actuated by depressing the brake pedal at the driver's seat to brake the wheels. It is something.

These types of disc brakes have two types: one type has cylinder parts that press the pads on both sides of the disc rotor, and the other has cylinder parts only on the inner side of the disc rotor, and the outer pads straddle the disc rotor from the outer periphery. Floating type in which the caliper moves and presses due to the reaction of the cylinder (an example is shown in Figure 5)
There are two types, and the latter has the advantage of having a simpler structure and requiring less installation space, so most current vehicles use this floating type.This invention also relates to the floating type. In the case of the floating type, when the brake is released, the piston on the inner side has a smaller weight, so the piston is pushed back by the reaction force of the pad member, making it easier for the pad member to separate from the disc rotor, but on the outer side, the weight of the caliper is smaller. Because of the large size, it is difficult to push back the caliper with only the reaction force of the pad member, so the disc rotor rotates while the pad is in slight contact with the disc rotor, causing a dragging phenomenon and causing an unpleasant dragging sound. However, there were problems such as premature wear of the pad.

In order to solve such problems, for example,
Publication No. 93527 discloses a system in which a return spring separates the pad from both sides of the disc rotor during normal operation, and during braking, a link mechanism is actuated by hydraulic pressure to press the pad against the disc rotor against the return spring. However, this type of braking device has a complicated structure, which is completely different from the floating type of the present invention, and furthermore, it has a vertically long form, which is disadvantageous in terms of installation space.

(Objective of the Invention) The present invention solves the above-described conventional problems and provides a braking device for a vehicle in which the outer pad member is configured to easily separate from the disc rotor, thereby eliminating the dragging phenomenon. The purpose is to

(Structure of the Invention) To achieve the above-mentioned object, the present invention provides a caliper that is installed in a caliper that is disposed astride the disc rotor from both sides of the disc rotor that is concentrically fixed to the axle and rotates together with the axle. A braking device (disc brake) that performs braking by bringing pads into contact by the pressing action of the piston and the movement of the caliper due to the reaction force of this pressing action. a member, a rod slidably inserted into the support member in a direction orthogonal to both side surfaces of the disc rotor, and a rod slidably slidable relative to the rod by a clearance between the disc rotor and the pad. The braking device for a vehicle includes a biasing means made of an elastic member that biases the supported caliper in a direction in which the piston is pressed.

According to this vehicle braking device, the sliding of the rod relative to the support member moves the caliper supported by the rod by the amount of wear on the outer pad, and the sliding of the caliper relative to the rod moves the outer caliper when the brake is released. The pad on the side moves away from the disc rotor to eliminate the dragging phenomenon of this pad. During braking, the caliper, which receives the hydraulic reaction force against the pressing force of the piston, compresses the elastic member that is the urging means and presses the piston. When the outer pad is pressed against the disc rotor by moving in the opposite direction and the braking force is released, the hydraulic reaction force that moves the caliper disappears, so the caliper moves against the disc rotor due to the elasticity of the elastic member. It moves in the pressing direction of the piston by the amount of clearance between the disc rotor and the outer pad, thereby creating a clearance between the disc rotor and the outer pad, thereby eliminating the dragging phenomenon.

(Embodiments) The present invention will be described below based on embodiments shown in the drawings.

In the main part cutaway plan view of the braking device of the present invention illustrated in FIGS. 1 and 2, the side view shown in FIG. 3, and the center sectional view of FIG. 1 shown in FIG. As shown in the overall perspective view of the conventional product shown in FIG. It rotates in the direction of the arrow R in Figure 3, and has friction surfaces (10a) on both sides.
) (10b), and this friction surface (10a) (1o
Pads (12) and (13) are arranged at positions corresponding to b), and these pads (12 and 13) have back plates (12a and 13a) fixed to their back surfaces, respectively. (12a) At both ends of (13a) there are protrusions (12
b) (13b) is provided.

(14) is a support member that is fixed to the vehicle body (not shown) and is a friction surface (10a) (1) of the disc rotor (10).
0b), and grooves (14a) (14b) are formed on the inward surfaces of the front and rear ends in a direction perpendicular to the friction surfaces (10a) (10b) of the disc rotor (10). (14a) (14b) and back plate (12a) (1
The protrusions (12b, 13b) of 3a) fit together, and the support member (14) moves the pads (12, 13) in a direction perpendicular to the friction surfaces (10a, 10b) of the disc rotor (10). It is movably supported.

A rod hole (15) is provided at the front and rear ends of the support member (14) in a direction perpendicular to the friction surfaces (10a) (10b) of the disc rotor (10).
5) has a rubber sleeve (15a) with splines on the inner surface.
) is fitted into the rod hole (15), and the rod (16) is inserted into the rod hole (15).
is slidably inserted, and a spline (16a) is formed on the outer periphery of the rod (16), which fits into the spline of the rubber sleeve (15a) to provide sliding resistance to the rod (16). are doing.

(17) is a caliper, which is arranged to straddle the disc rotor (10) and pads (12) and (13) from the outer periphery, and has a boss part (17a) formed at the front and rear ends that is slidably fitted to the rod (16). The cylinder (18) is slidably fitted and supported by the small diameter part (16b) which is supported by the cylinder (18) corresponding to the back plate (12a) of the inner pad (12).
This cylinder (18) has a pressure oil inlet (18a) at the rear end and a piston (19) fitted therein, and the tip of this piston (19) is fitted with a pad (18a).
2) is in contact with the back plate (12a).

(20) is a stopper, which is a small diameter part (1) of the rod (16).
6b), and is positioned by a nut (21) which is screwed into the end of the small diameter portion (16b), and the movement width of the caliper (17) is controlled as shown in FIG. The clearance is regulated to be equal to the clearance (α) between the disc rotor (10) and the outer pad (13).
) A spring (22) is interposed between the caliper (
17) in the pressing direction of the piston (19) (in the direction of the arrow X in FIG. 4).

(23) is a seal ring that prevents oil leakage from the sliding part between the cylinder (18) and the piston (19);
24) is a dust seal that prevents dust from entering into the cylinder (18), and (25) and (26) are dust boots that seal the rod (16), the rod hole (15), and the boss of the caliper (17). This prevents dust from entering the sliding part with the part (17a).

This concludes the explanation of the configuration, and then the operation will be explained.

FIG. 1 shows a state in which the brake is released, and the disc rotor (10) moves from the rotation side (R1) to the rotation side (R1).
2), and the friction surfaces (10a) (10b) on both sides
) The pads (12) and (13) corresponding to the pads (12) and (13) are respectively located with clearances (α) and (β), and the disc rotor (lO ) and the outer pad (13) (α) and a clearance (α′) equal to the gap (α)
With the spring (22), the piston (19)
is urged in the pressing direction, that is, in the right direction in FIG.

When the brake pedal (not shown) is depressed from the state shown in FIG. 1
8a) into the cylinder (18) and the piston (
19) in the direction of the arrow X in Fig.
0a), move the caliper (17) in the direction of the arrow Y in Figure 4, and press the pad (13) on the outer side.
) The two bent portions (17b) of the caliper (17) that are in contact with the back plate (13a) of the pad (13) press the pad (13) against the friction surface (10b) of the disc rotor (10), ) (13) achieves braking by sandwiching the disc rotor (10) from both sides.

At this time, the caliper (17) moves toward the outer friction surface (10b) of the disc rotor (10) in the direction of the Y arrow in FIG.
and the clearance (α) between the pad (13) on the outer side
), the boss (17a) compresses the spring (22), slides on the small diameter part (16b), and comes into contact with the stopper (20), increasing the clearance ( As shown in Fig. 2, α') only changes its position between the opposite end surface of the boss portion (17a) and the step of the small diameter portion (16b), and the rod (16) does not move, but the outer pad ( 13) is worn, the rod (
16) comes out from the rod hole (15), and the caliper (17)
moves in the direction of the Y arrow in Figure 4 (to the left in Figure 2) and moves the outer pad (13) to the disc rotor (
10) is brought into pressure contact with the friction surface (10b).

In this way, the braking state shown in Fig. 2 is reached, and when the brake pedal is released from this braking state to release the braking, the pressure of the pressure oil in the cylinder (18) disappears, and the pressing force of the piston (19) disappears. Since the piston (19) has a small weight, the pad (12) on the inner side is pushed back by the reaction force of the rotation of the disc rotor (10), and the friction surface (10a) of the disc rotor (10)
A clearance (β) is created between the pad (12) and the
At the same time, the caliper (17) is pushed in the pressing direction of the piston (19) by the repulsive force of the spring (22) that overcomes its own large weight, so the outer pad (13)
is pushed back by the rotation of the disc rotor (10) in the same way as the inner side, and the friction surface (10b) and pad (13
), a gap (α) is created between the two.

In this way, the caliper (17), which conventionally had difficulty returning due to its weight when the brake is released, can now return easily, and the dragging phenomenon of the outer pad (13) can be eliminated.

In the above operation, the caliper (17) moves to the fourth position during braking.
When moving in the direction of the arrow Y in the figure, the boss part (17a) compresses the spring (22) and moves on the small diameter part (16b), preventing the rod (16) from moving.
It is necessary to make the sliding resistance of the rod (16) larger than the pressure of
.

and the rod (16) are spline-fitted to increase the sliding resistance. Even with this large sliding resistance, the hydraulic pressure acting on the caliper (17) is even stronger, so that the pad (13) wears out. It is easy to move the rod (16) by that amount.

In addition, the structure of the above-mentioned rod (16) may be the same for both the front and rear, or only one of the two may have the above structure, and the other one may be a simple conventional guide bin. You can also use it as

(Effects of the Invention) According to the vehicle braking device according to the present invention as described above, the caliper, which is difficult to move due to its weight when the brake is released, is forcibly moved by the urging force of the urging means, and the pad is moved between the disc rotor and the caliper. It is possible to maintain a constant clearance at all times by separating the pad from the disc rotor, eliminate the dragging phenomenon where the pad contacts the disc rotor when the brake is released, eliminate unpleasant dragging noise, and prevent pad wear due to the dragging phenomenon. It is something.

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of this invention.
Fig. 1 is a cutaway plan view of the main part when the brake is released, Fig. 2 is a cutaway plan view of the main part when the brake is applied, Fig. 3 is a side view of Fig. 1 when viewed in the direction of arrow A, and Fig. 4 is a cutaway plan view of the main part when the brake is released. A cross-sectional view along the ■-■ line in Figure 2,
FIG. 5 is an overall perspective view showing an example of a conventional braking device. 10...Disc rotor 10a, 10b...Friction surface 11...Axle 12.13...Pad 14...Support member 15...Rod hole 16...Rod
17...Caliper 18...Cylinder 19...
Piston 20... Stopper 22... Spring (biasing means) α, α', β... Clearance Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] Braking is achieved by bringing pads into contact from both sides of a disc rotor, which is concentrically fixed to an axle and rotates together with the axle, by the pressing action of a piston built into a caliper that straddles the disc rotor. The braking device includes a support member supported by the vehicle body, a rod slidably inserted into the support member in a direction orthogonal to both side surfaces of the disc rotor, and a rod that is slidably inserted into the support member in a direction perpendicular to both sides of the disc rotor. , comprising a biasing means made of an elastic member that biases the caliper, which is slidably supported by the clearance between the disc rotor and the pad, in the direction in which the piston is pressed; Braking device for vehicles.