KR20010090083A - Apparatus for adjusting gap between brake pads and wheel drum in vehicles - Google Patents

Abstract

A brake force generating unit 10 including a brake pedal 11 and a master cylinder 12 for generating hydraulic pressure by pressurizing the brake fluid according to the automatic operation of the brake pedal and the hydraulic pressure generated by the brake force generating unit 10. Spacing adjustment is provided in the pipe 30 to interconnect the brake unit 20 including the brake pad 22 for selectively pressing and braking the wheel drum 21 to adjust the distance between the wheel and the brake pad An apparatus comprising: a cylinder member (200) installed in the pipe to have an inlet (40) through which the brake fluid flows from the braking force generating section and an outlet (50) outflow of the brake liquid to the braking portion; And installed in the cylinder member so as to reciprocate according to the hydraulic pressure generated from the braking force generating unit, respectively, the space inside the cylinder member to the inlet space 200A on the inlet side and the outlet space 200B on the outlet side, respectively. In a normal state in which the brake pad is not worn when the brake is operated, the brake pad is worn out while the hydraulic pressure applied to the inflow space is transferred to the outlet space as it is in the cylinder member. In the intercommunication between the inflow space and the outflow space, the fluid flows to the outflow space, thereby supplementing the hydraulic pressure corresponding to the degree of wear of the brake pad to approach the brake pad to the wheel drum, and then back to the inflow space. Piston assembly that isolates the part from the outlet space 300; the vehicle wheel drum and the spacing of the brake pad adjustment device comprises a are provided.

Description

Apparatus for adjusting gap between brake pads and wheel drum in vehicles}

The present invention relates to a gap adjusting device between a brake pad and a wheel drum of a vehicle. More specifically, the brake pad is worn and the brake pad is automatically adjusted and compensated when a gap occurs between the wheel drum. A device for providing frictional force is provided.

A brake attached to a vehicle is a device for stopping a vehicle in motion and maintaining the stopped vehicle in a stopped state. The brake is provided on each wheel of the vehicle by generating hydraulic pressure using a force or an auxiliary power generated by a driver's operation. And to stop the drum with friction.

In general, the brake system is divided into a braking force generating unit 10 (Actuation unit), a braking unit 20, and an auxiliary unit, the braking force generating unit 10 by using the driver's operation or auxiliary power to brake the force required for As a part to generate | occur | produce, it comprises components, such as a master cylinder, a booster, an air master, and an air chamber.

The braking unit 20 functions to actually decelerate or stop the vehicle by using the force generated by the braking force generating unit 10, and a drum brake and a disk brake belong to the braking unit 20.

In addition, the auxiliary part is composed of a vacuum pump, an air compressor, etc. for obtaining auxiliary power, a pipe, a valve, etc. for transmitting a braking force.

In the brake system of the vehicle, the drum brake system brakes the wheel by a friction force generated by bringing a brake lining into close contact with a wheel drum provided on a rotating shaft that is rotated by an engine. The brake lining is attached to a brake shoe which is operated by a wheel cylinder.

In addition, the disc brake system stops the wheel by generating a friction force by bringing a brake pad into close contact with both sides of the wheel disk provided on the rotating shaft.

The brake lining and the brake pad are usually manufactured by mixing organic binders such as phenol resins, metal fibers such as iron and brass, and ceramics together with materials such as friction stabilizers, friction adjusting agents, and lubricants. In general, in a vehicle, a surface pressure of 5 to 7 kg / cm 2 or more is applied to the pad during brake operation, and a high temperature of 150 ° C. or more is generated. The brake pads are gradually worn out over time due to friction with the wheel drums and the thickness thereof decreases. As the brake pads are worn out, the distance between the brake pads and the wheel drums is further increased, and as a result, the driver brakes. The pedal should be pressed deeper.

Therefore, in view of the above problems, a method of installing a gap adjusting device between a pair of brake shoes and adjusting the distance between the brake shoes has been proposed. However, such a device is not only cumbersome, such as manual operation by a person, and wheels need to be detached from the wheel drum for this purpose. There is also a risk of accidents.

The present invention is to solve the above problems, the brake pad and the wheel drum of the vehicle that can check the interval between the brake pad and the wheel drum with a change in the hydraulic pressure and automatically adjusts the gap when this exceeds a predetermined reference value The purpose is to provide a spacing device between them.

It is still another object of the present invention to provide an apparatus capable of automatically adjusting the distance between the brake pad and the wheel drum without the need to separate the wheel from the wheel or the user manually.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic configuration of a brake system employing a brake spacing device according to a preferred embodiment of the present invention.

Figure 2 is a partially cut perspective view showing a brake spacing device according to a preferred embodiment of the present invention.

Figures 3a and 3b are views showing the configuration of the piston assembly of the spacing device according to the invention according to the operating state.

Figure 4 is an exploded perspective view of the piston assembly of the spacing device according to the invention.

5 to 8 are cross-sectional views each showing an operating state of the piston assembly of the spacing device according to the present invention.

9 is an enlarged cross-sectional view of the operation of the piston assembly;

10 is a cross-sectional view showing a configuration of a support member employed in the piston assembly.

11 is a sectional view showing a configuration of a valve member employed in the piston assembly.

12 is a cross-sectional view showing a configuration of a blocking member employed in the piston assembly.

In order to achieve the above object, an apparatus for adjusting a gap between a brake pad and a wheel drum of a vehicle according to the present invention includes a brake pedal and a master cylinder for generating hydraulic pressure by pressurizing brake fluid according to the automatic operation of the brake pedal. A braking force generating unit and a braking unit including a brake pad for braking by selectively pressing the wheel drum according to the hydraulic pressure generated by the braking force generating unit and installed in a pipe interconnecting each other to adjust the distance between the wheel and the brake pad. As a spacing device,

A cylinder member installed in the pipe to have an inlet through which the brake fluid flows from the braking force generation unit and an outlet through which the brake fluid flows out of the braking unit; And

It is installed in the cylinder member to reciprocate according to the hydraulic pressure generated from the braking force generating unit to isolate and isolate the space inside the cylinder member into the inlet space portion on the inlet side and the outlet space portion on the outlet side, respectively, during brake operation In the normal state in which the brake pad is not worn, the hydraulic fluid applied to the inflow space portion is transferred to the outflow space portion as it moves forward in the cylinder member, while the inflow space portion and the outflow space are in the state where the brake pad is worn. The parts are communicated with each other so that the brake fluid flows to the outlet space to compensate for the hydraulic pressure corresponding to the degree of wear of the brake pads, thereby accessing the brake pads to the wheel drum, and then blocking and separating the inflow space and the outlet space again. Including piston assembly .

The piston assembly,

A moving cylinder block reciprocating inside the cylinder member; A piston shaft supporting the movable cylinder block to move to the yield point; Is installed inside the moving cylinder block, when the moving cylinder block is moved beyond the yield point to within the adjustment point, the inflow space and the outlet space portion is still isolated, and the moving cylinder block is moved to the adjustment point Valve means for allowing the fluid flow to communicate with the inflow space portion and the outflow space portion; And blocking means for blocking a brake fluid from flowing backward from the outlet space portion to the inlet space portion.

Preferably, the valve means,

A yield cylinder block slidably inserted into the moving cylinder block and inserted into the piston shaft to reciprocate therein; An inflow sealing member having a hollow portion and fixed to and supported by the yield cylinder block; An insertion part coupled to the head of the moving cylinder block and forcibly fitted into the hollow part of the inflow sealing member is formed, and an inlet valve hole communicating forward is formed on the outer circumferential surface of the insertion part to open and close the valve by the inflow sealing member. absence; And an elastic member interposed between the yield cylinder block and the moving cylinder block to elastically bias the yield cylinder block forward.

When the movable cylinder block reaches the adjustment point, the yield cylinder block is prevented from moving forward by the piston shaft, and the inlet valve hole is opened while the insertion portion of the valve member exits from the hollow portion of the inflow sealing member. It is characterized by.

Also preferably, the blocking means,

A blocking member coupled to the valve member and in communication with an inlet valve hole of the valve member and having an outlet valve hole leading to the outlet space part; And a backflow sealing member coupled to an outer circumferential surface thereof to close the outlet valve hole of the blocking member.

According to a more preferred embodiment of the present invention, a passage for communicating the inlet space portion and the outlet space portion of the cylinder member with each other; And a valve for opening and closing the passage.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the present specification and claims should not be construed as being limited to the common or dictionary meanings, and the inventors should properly explain the concept of terms in order to explain their own invention in the best possible way. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

The gap adjusting device of the present invention can be applied to both a drum brake system and a disc brake system. As described above, in the drum brake system, the present invention is adopted to adjust the distance between the wheel drum and the brake lining mounted on the brake shoe, and in the disc brake system, the distance between the wheel disc and the brake pads installed on both sides thereof is adjusted. The present invention can be employed for this purpose. That is, the present invention is in close contact with the rotor member is coupled to a rotating shaft that receives the power of the vehicle engine, such as the wheel drum or wheel disk, and the rotating rotor member, such as the brake lining or brake pad to generate a friction force All may be applied to adjust the gap between the friction members. Hereinafter, in the present specification and claims, the rotor member will be referred to as a 'wheel drum', and the friction member will be referred to as a 'break pad'. Accordingly, the wheel drum and brake pads described in the following specification and claims should be understood to encompass all of the above components, and should not be construed as limited to the specific embodiments of the drawings attached to the present specification.

1 shows a brake system having a gap adjusting device between a brake pad and a wheel drum of a vehicle according to the present invention. As shown in the figure, the brake system has a braking force generating unit 10 for generating power to provide a friction force, a braking unit 20 for decelerating or stopping the vehicle by the generated braking force and the braking force generating unit ( 10) a pipe 30 for transmitting the power generated in the brake unit 20.

The braking force generation unit 10 further includes a brake pedal 11 that the driver manipulates with his feet to decelerate or stop the vehicle, and a master cylinder 12 connected to the brake pedal 11 to generate hydraulic pressure. The master cylinder 12 communicates with the tank 13 containing the brake fluid so as to receive the brake fluid. In addition, the braking force generating unit 10 is connected to the brake pedal 11 to assist the driver, such as a vacuum booster (vacuum booster) (not shown), which functions to increase the braking force generated by stepping on the brake pedal 11. A power unit may be provided.

A drum brake system is shown according to the preferred embodiment of the invention as the brake 20. Referring to the drawings, the brake unit 20 rotates the wheel drum by selectively contacting the wheel drum 21 and the wheel drum 21 coupled to the rotating shaft of the wheel rotated by the engine of the vehicle to provide frictional force. The brake pad 22 is provided to decelerate or stop the engine. The wheel drum 21 may be mounted with a tire wheel (not shown) of the vehicle.

In addition, the brake pads 22 are preferably attached to a pair of brake shoes 23, which are connected by a restoring spring 24 and elastically biased to access each other, between them. The wheel cylinder 25 is provided to move in a direction away from each other. The hydraulic pressure generated from the braking force generating unit 10 is applied to the wheel cylinder 25 through the pipe 30. Therefore, when the driver generates the braking force by stepping on the brake pedal 11, the brake shoe 23 and the brake pad 22 mounted thereon are pushed toward the wheel drum 21 by the wheel cylinder 25 and the wheel The frictional force is provided by contacting the drum, and conversely, when the driver releases the brake pedal 11 to release it, the frictional force is removed by returning to the original position by the restoring force of the restoring spring 24.

The gap adjusting device 100 according to the present invention is installed to be interposed on a pipe 30 through which the hydraulic pressure between the braking force generating unit 10 and the braking unit 20 is transmitted. Preferably, in the case of automobiles, since the brake system exists for each wheel, the gap adjusting device of the present invention may be installed for each of these wheels.

Referring to Figure 2 showing the gap adjusting device 100 in detail, the device of the present invention is a cylindrical cylinder member 200 and the piston assembly 300 reciprocating in accordance with the hydraulic pressure in the cylinder member 200 It includes. One end and the other end of the cylinder member 200 are formed with an inlet 40 and an outlet 50 through which brake fluid flows from the braking force generating unit 10 and outflows into the braking unit 20 as described below.

An operating state of the piston assembly 300 reciprocating in the cylinder member 200 is shown in FIGS. 3A and 3B. 3A illustrates a state in which the brake is not operated, and FIG. 3B illustrates a state in which a driver presses the brake pedal 11 to apply hydraulic pressure.

The piston assembly isolates and separates the space inside the cylinder member into the inflow space and the outflow space, respectively, and during brake operation, if the brake pad is in a normal, unworn state, it simply moves forward to transmit hydraulic pressure, while When the brake pad is worn, the inflow space portion and the outlet space portion communicate with each other so that the brake fluid flows to the outlet space portion, thereby replenishing the hydraulic pressure corresponding to the degree of wear of the brake pad and thus the worn brake. After approaching the pad to the wheel drum, it functions to isolate and isolate the inflow space and the outflow space again. Detailed description thereof will be described later.

A more detailed configuration of such a piston assembly 300 is shown in FIGS. 4 and 5. Referring to the drawings, the piston assembly 300 includes a base member 310, a moving cylinder block 330, a valve means, and Blocking means.

The valve means maintains an isolation state of the inflow space portion and the outflow space portion when the moving cylinder block does not move to a predetermined point when the brake is operated, and when the moving cylinder block moves to a predetermined point, the inflow space It serves to flow the brake fluid by communicating the part and the outlet space with each other. The valve means is a yield cylinder block 350, the support member 370, the support member 370, the valve member 380, and the support member 370, which is slidably installed in the movable cylinder block 330. And an inflow sealing member 320b coupled between the valve member 380.

In addition, the blocking means, as a function to block the brake fluid from flowing back from the outlet space portion to the inlet space portion, is coupled between the blocking member 390 and the valve member 380 and the blocking member 390. The backflow sealing member 320c is included.

The base member 310 is a base for supporting the movable cylinder block 330 to reciprocate in the cylinder member 200, the inlet hole 311 is formed so that the brake fluid can be introduced The inlet hole 311 communicates with the inside of the cylinder member 200. Preferably, the base member 310 is formed with a screw portion 313 is mutually coupled to the screw portion formed on the inner peripheral surface of the inlet 40 of the cylinder member 200.

The piston shaft 360 is coupled to the base member 310. Preferably, the end of the piston shaft 360 is screwed to and fixed to the fastening portion 314 of the base member 310. Here, the piston shaft 360 is coupled to the base member 310 through the yield cylinder block 350 and the moving cylinder block 330. That is, a hollow part is formed in the yield cylinder block 350 and the moving cylinder block 330, and the piston shaft 360 is sequentially coupled to the base member 310 by passing through the hollow parts. In this case, a nail head 361 is formed at the other end of the piston shaft 360. The diameter of the nail head 361 is smaller than the inner diameter of the yield cylinder block 350, whereas the yield cylinder block 350 is formed. It is larger than the through hole formed in the tail of the. Accordingly, the piston shaft 360 is moved within the stroke distance that the nail head 361 is applied to the tail portion of the yield cylinder block 350 in reciprocating the interior of the yield cylinder block 350.

In addition, the outer diameter of the yield cylinder block 350 is smaller than the inner diameter of the moving cylinder block 330, the yield cylinder block 350 is inserted into the moving cylinder block 330. Accordingly, as shown in FIG. 5, the piston shaft 360 penetrates them and is coupled to the base member 310 while the yield cylinder block 350 is inserted into the moving cylinder block 330. do.

An elastic member 340 such as a spring is interposed between the yield cylinder block 350 and the movable cylinder block 330, and the elastic member 340 separates the yield cylinder block 350 from the moving cylinder block 330. Elastic bias in the pushing direction (ie, forward).

The moving cylinder block 330 is a component that transmits the hydraulic pressure to the brake unit 20 by moving in the cylinder member 200 due to the hydraulic pressure generated by the inflow of the brake fluid. The moving cylinder block 330 is provided with a piston ring 320a for sealing with the inner wall of the cylinder member 200. For example, as many fastening grooves 331 as necessary on the outer circumferential surface of the moving cylinder block 330. It is preferred that the annular piston ring 320a is coupled thereto. Preferably, the piston ring 320a is made of an elastic member such as rubber. In this embodiment, four piston rings 320a are provided to increase the sealing effect. Due to the sealing action of the piston ring 320a, the interior of the cylinder member 200 is divided into two independent spaces, which are connected to the master cylinder 12 of the braking force generating unit (10 in FIG. 1) to which hydraulic pressure is applied. This is the area 200B connected to the 200A and the braking unit 20 to apply hydraulic pressure. In the present specification, these areas are divided into inflow space portions 200A and outflow space portions 200B, respectively.

According to the present invention, the brake fluid introduced into the cylinder member 200 from the braking force generating unit 10 flows into the moving cylinder block 330 and the yielding cylinder block 350, more specifically, the movement. A communication hole 332 is formed in the cylinder block 330 so that the inflow space 200A and the inside of the moving cylinder block 330 communicate with each other, and the yielding cylinder block 350 has the moving cylinder block 330. Communication holes 351 and 352 communicating with the interior of each are formed. The shape and number of these communicating holes are not limited by this embodiment and the drawings. Accordingly, the brake fluid introduced into the cylinder member 200 may flow through the communication holes 332, 351, and 352 in order to flow into the inside of the moving cylinder block 330 and the yielding cylinder block 350. will be.

The support member 370 is coupled to the head of the yield cylinder block 350, the configuration of which is shown in detail in the cross-sectional view of FIG. The support member 370 serves to support and fix the inflow sealing member 320b to the yield cylinder block 350. In addition, the support member 370 has a hollow 371 from the head to the tail is formed so that when coupled to the yield cylinder block 350 as shown in Figure 5 is in communication with the interior of the yield cylinder block 350, The function of this hollow 371 will be described later. A locking jaw 372 is formed at the head of the support member 370 so that the inflow sealing member 320b may be coupled and supported. The inflow sealing member 320b is a member having a hollow portion formed of an elastic material such as rubber, and is coupled to and fixed to the support member 370.

The valve member 380 is coupled to the inflow sealing member 320b opposite the support member 370, and the configuration of the valve member 380 is illustrated in detail in FIG. 11. As described later, the valve member 380 automatically wears the inlet space 200A and the outlet space 200B when the brake pad 22 is worn and an interval between the wheel drum 21 and the brake pad 22 increases. And a function of controlling the brake gap by communicating the flow of the brake fluid, and inserting the screw portion 381 and the hollow portion of the inflow sealing member 320b coupled to the head of the moving cylinder block 330. Has an inserting portion 382. A plurality of inlet valve holes 383 are formed in the insertion portion 382, which is connected to the hollow portion 384 and communicates forward. The insertion part 382 is fit-fitted into the hollow portion of the inflow sealing member 320b, and as described later, when the hydraulic pressure increases according to the driver's brake operation, the direction is separated from the hollow portion of the inflow sealing member 320b. Will be moved to.

The blocking member 390 is coupled to the valve member 380 again. As shown in FIG. 12, the screw portion 391 formed on the outer circumferential surface of the blocking member 390 and the screw portion formed on the inner circumferential surface of the valve member 380 are mutually interchangeable. Are fastened together. The blocking member 390 serves to block the flow of the brake fluid from the inflow space 200A to the outflow space 200B and prevent flow back in the reverse direction, and the outflow space 200B and its outer peripheral surface. A plurality of outlet valve holes 392 are formed to communicate with each other, and the outlet valve holes 392 are connected to the hollow 393 so as to communicate rearwardly. Thus, the inlet valve hole formed in the valve member 380 and the outlet valve hole 392 formed in the blocking member 390 are interconnected by the hollows formed in each of them.

The reverse flow sealing member 320c is coupled to the outer circumferential surface on which the outlet valve hole 392 of the blocking member 390 is formed to block the reverse flow of the brake fluid as described below. Preferably, the material of the backflow sealing member 320c is the same as the inflow sealing member 320b described above.

Looking at the operation of the inlet valve hole 383 and the outlet valve hole 392 formed in the valve member 380 and the blocking member 390, although the sealing members (320b, 320c) is a valve hole (383) ( 392 is closed, but a high pressure of 200 kg / cm 2 or more is applied when the brake is operated, so that it is possible to overcome the pressing force of the sealing members from the valve hole and allow the brake fluid to flow to the outside, but on the contrary, the members 380 and 390 from the outside. Inflow into the valve hole 383 and 392 through the gap between the c) and the sealing members 320b and 320c is blocked. That is, these valve balls and sealing members serve as one-way valves.

Here, the inlet valve hole 383 and the outlet valve hole 392 are not directly formed on the outer circumferential surfaces of the members 380 and 390, but instead form grooves of a predetermined depth in the outer circumferential surfaces of the members. And are formed in this groove. Because the sealing members 320b and 320c are made of rubber, and if the valve hole is formed without these grooves, the above high pressure is applied during the brake operation, so that the sealing members may be broken or holes may be formed. This is because the blocking effect cannot be obtained. The groove has been found to improve the durability of the sealing member and to increase the effect of the hydraulic cutoff by preventing the concentration of pressure in the local region where the valve hole by dispersing such high pressure.

As can be seen from the above configuration, in the gap adjusting device of the present invention, the inlet space 200A and the outlet space 200B in the cylinder member 200 are completely blocked in the normal state. That is, the flow of the brake fluid is blocked by the piston ring 320a which is in close contact with the inner circumferential surface of the cylinder member 200 and the backflow sealing member 320c which is coupled to the outer circumferential surface of the blocking member 390.

This will be described in detail with respect to the operation of the gap adjusting device according to the present invention having the configuration as described above.

Installation of spacer

Prior to the description of the operation of the spacing device according to the present invention, a brief description will be made of a method for installing such spacing device in the pipe. The gap adjusting device of the present invention can be simply installed on the pipe 30 without removing the tire from the wheel drum 21. That is, the pipe 30 is cut and installed to connect the inlet 40 and the outlet 50 of the cylinder member 200 to the braking force generating unit 10 and the braking unit 20, respectively. Then, the inside of the inlet space 200A and the outlet space 200B is filled with the brake fluid, wherein the air in the existing space may be discharged through the air outlet (110a, 110b of Figure 1). Then, the operation of the gap adjusting device is installed as described above will be divided into the normal case and the worn state will be examined.

Normal brake operation

In FIG. 1, the brake operation will be described when the distance between the wheel drum 21 and the brake pad 22 is normal. When the driver presses the brake pedal 11 with the foot to apply pressure to decelerate or stop the speed while the vehicle is running, the master cylinder 12 generates hydraulic pressure. Preferably, this hydraulic pressure can be further increased by an auxiliary power unit such as a vacuum booster (not shown). At this time, the brake fluid flows along the pipe 30 and flows to the inlet 40 of the cylinder member 200 of the gap adjusting device according to the present invention as shown in FIG. 5.

The brake fluid flowing into the inlet 40 flows into the inlet space 200A of the cylinder member 200 through the inlet hole 311 of the base member 310, and this hydraulic pressure is applied to the moving cylinder block 330. Therefore, the moving cylinder block 330 moves forward. At this time, since the inflow space 200A and the outflow space 200B inside the cylinder member 200 are blocked by each other by the piston ring 320a and the backflow sealing member 320c, the pressing force due to the inflow of the brake fluid is entirely. Moving to the cylinder block 330.

Looking at this state in more detail, in the state in which the valve member 380 and the moving cylinder block 330 is coupled, the yield cylinder block 350 inserted into the moving cylinder block 330 by the elastic member 340. It is elastically biased forward. Therefore, since the inflow sealing member 320b is also elastically biased forward by the support member 370 coupled to the yield cylinder block 350, the insertion portion 382 of the valve member 380 is the inflow sealing member 320b. It is tightly fitted into the hollow part of the. In this state, since the inflow valve hole 383 formed in the insertion portion 382 of the valve member 380 is closed by the inflow sealing member 320b, the brake fluid cannot be introduced. On the other hand, since the piston shaft 360 is capable of reciprocating without any resistance in the yield cylinder block 350, when the brake fluid flows into the inflow space 200A according to the operation of the brake pedal, the moving cylinder block 330 The surrender cylinder block 350 is to be moved forward.

The moving state of the moving cylinder block 330 is shown in FIG. 6, and as shown, the moving cylinder block 330 advances from the initial point A to the break yield point B. FIG. The distance between these points is equal to the stroke distance that the piston shaft 360 moves in the yield cylinder block 350. The yield point B is the maximum distance that the moving cylinder block 330 can move forward when the driver presses the brake pedal as much as possible, and the maximum hydraulic pressure is applied to the brake unit 20 at this point. In the following claims, the term 'yield point' will be used in the same sense without any definition.

According to the present invention, even if the moving cylinder member 200 is advanced to the yield point (B), there is a predetermined distance (D) therebetween without contacting the cylinder member (200).

When the hydraulic pressure of the outlet space 200B rises according to the above process and is transmitted to the wheel cylinder 25 of FIG. 1, the brake shoes 23 are pushed in opposite directions by the operation of the wheel cylinder. The attached brake pads 22 come into contact with the wheel drum 21 to provide frictional force, causing the wheels to stop.

Subsequently, when the driver releases the brake pedal 11, the hydraulic pressure of the master cylinder 12 decreases, so that the pressure of the inflow space 200A decreases, and the brake is restored by the restoring spring 24 of the brake 20. As the shoe 23 is pulled, the brake fluid flows back by the force, and thus the moving cylinder block 330 in the cylinder member 200 retreats and returns to its original point.

Example of brake clearance adjustment

As the number of brake operations increases, the brake pads 22 of the brake unit 20 gradually wear and thus reduce their thickness. Then, when the driver presses the brake pedal, even if the moving cylinder block 330 advances to the yield point B of FIG. 6, the brake pad 22 may not be in sufficient contact with the wheel drum 21 to obtain sufficient braking force. do. Accordingly, the driver must step deeper on the brake pedal 1 in order to obtain sufficient braking force, thereby increasing the play of the brake pedal. As a result, the moving cylinder block 330 in the cylinder member 200 is advanced beyond the yield point (B) to one point (C ') between the adjustment point (C), which is the point where the interval adjustment is made. The state is shown in FIG.

In more detail with reference to FIG. 7, when the driver increases the hydraulic pressure of the inflow space 200A by further stepping on the brake pedal 11 in the state where the moving cylinder block 330 reaches the yield point B, the yield is increased. Since the cylinder block 350 is prevented from moving further by the piston shaft 360, the cylinder block 350 moves forward while overcoming the elastic force of the elastic member 340.

At this time, since the valve member 380 coupled to the head of the moving cylinder block 330 is also advanced, the insertion portion of the valve member 380 gradually exits from the hollow portion of the inflow sealing member 320b. In addition, the brake fluid introduced into the cylinder member 200 flows into the communication holes 332, 351, 352 formed in the moving cylinder block 330 and the yielding cylinder block 350 to hollow the support member 370. This action can be further promoted by pushing the rear end of the insertion portion 382 fitted to the hollow portion of the inflow sealing member 320b through.

However, even in this state, since the insertion portion of the valve member 380 does not completely exit from the inflow sealing member 320b, the inflow valve hole 383 formed in the insertion portion is still closed by the inflow sealing member 320b. The brake fluid does not flow into the inlet valve hole 383.

When the brake pad 22 is further worn and the clearance of the brake pedal 11 becomes greater, the moving cylinder block 330 finally moves to the adjustment point C. The adjustment point C is the valve member ( 380 is defined as a point at which the inlet valve hole 383 opened out of the hollow of the inlet sealing member 320b and closed by the inlet sealing member 320b. In the following claims, the term 'adjustment point' will be used in the same sense without definition. The state in which the inlet valve hole 383 is opened is illustrated in FIG. 8, and is partially enlarged in FIG. 9.

Once the inlet valve hole 383 is opened, as shown by the arrow of FIG. 8, the brake fluid in the cylinder member 200 flows into the inlet valve hole 383 and then the hollow portion of the valve member 380. And it passes through the hollow portion of the blocking member 390 flows into the outlet space 200B through the outlet valve hole 392 of the blocking member 390. As described above, the outlet valve hole 392 of the blocking member 390 is closed by the backflow sealing member 320c, but the brake fluid applied at high pressure may flow out of the blocking force. In this way, the brake fluid flowing into the outflow space 200B flows back to the wheel cylinder 25 to operate the brake fluid 23 to bring the brake shoe 23 closer to the wheel drum 21 by that amount, and thus the brake pad 22. By advancing toward the wheel drum 21 by the worn thickness, it is possible to maintain the gap therebetween in its original proper state.

In this way, the hydraulic pressure of the outlet space 200B is reduced to some extent by the moment when the distance between the brake pad 22 and the wheel drum 21 is adjusted to be in equilibrium with the hydraulic pressure of the inlet space 200A, and then the movement The cylinder block 330 is again subjected to the bias of the elastic member 340 to retreat back, this operation is performed while the driver is still pressing the brake pedal (11).

As a result, the movable cylinder block 330 retreats to the yield point B, which was the original equilibrium point, and stops. At the same time, the valve member 380 is inserted into the hollow part of the first sealing member 320b, thereby allowing the inlet valve hole ( 383) is closed as it is. On the other hand, since the brake fluid on the outlet space 200B side is blocked by the backflow sealing member 320c to the outlet valve hole 392 of the blocking member 390, the inflow space 200A and the outlet space portion are blocked. The communication of 200B is again blocked and the two are separated from each other.

After the distance between the brake pad 22 and the wheel drum 21 is adjusted in this way, the next time the driver presses the brake pedal 11 again, the brake pedal does not have to be stepped on as deeply as before the brake gap is corrected. Therefore, the maximum braking force is applied when the moving cylinder block 330 reaches the yield point (B). This effect allows the driver to always operate the brake pedal with the same play.

Embodiment of the brake hydraulic releasing means

According to another embodiment of the present invention, there is provided a brake spacing device having a means for easily releasing the hydraulic pressure applied in the outlet space (200B). As described above, even if the distance between the brake pad 22 and the wheel drum 21 is adjusted as the brake pads are worn, they must be replaced after all the brake pads 22 are worn out. If it is necessary to remove the wheel drum 21 or the brake shoe 23 or the pad 22 for the replacement of such parts or the repair of the vehicle, the work may not be easy due to the narrow space between the brake pad and the wheel drum.

In this case, using the hydraulic release means installed in the gap adjusting device of the present invention, the hydraulic release means is a passage 120 for connecting the inlet space 200A and the outlet space 200B as shown in FIG. And a valve 130 installed on the passage.

Therefore, when the operator wants to release the hydraulic pressure by turning the valve 130 to communicate with the inlet space 200A and the outlet space 200B mutually relative to the outlet space 200B side by the restoring spring 24 As the high pressure brake fluid is discharged into the inlet space 200A, the hydraulic pressure of the outlet space 200B is dropped. Therefore, since the hydraulic pressure applied to the wheel cylinder 25 is released, the brake shoe 23 and the pad 22 are retracted from the wheel drum 21, so that the operator can easily perform the work.

In addition, the present invention can be employed over all vehicle models, in which the stroke distance of the moving cylinder block can be easily adjusted. That is, in the case of small vehicles, the stroke distance is relatively short compared to the large vehicle, so that the stroke distance can be adjusted by selectively coupling the washer to the piston shaft to fit the length. Such a configuration is much cheaper than the prior art in which the spacing device must be manufactured separately for each vehicle type.

According to the brake gap adjusting device of the present invention, when the change in the hydraulic pressure according to the wear degree of the brake pad is automatically detected, if the value exceeds a predetermined reference value by applying more hydraulic pressure corresponding to the wear level between the brake pad and the wheel drum Allow to adjust the spacing of This saves you the hassle of manually or mechanically having to stop the vehicle to adjust the brake clearance.

In addition, the gap adjusting device according to the present invention can be installed arbitrarily in the pipe between the braking force generating portion and the braking portion of the brake, it is very convenient to install or maintain compared to the device that required mounting only on the wheel portion of the conventional wheel.

Furthermore, the present invention provides a more accurate method according to the difference between the hydraulic pressure generated from the brake pedal operated by the driver and the hydraulic pressure applied to the brake unit, compared to the conventional adjustment device, which was inaccurate by visually grasping the gap between the brake pad and the wheel drum by hand. By adjusting the interval, the accuracy and reliability are very high.

Claims (10)

A brake force generating unit 10 including a brake pedal 11 and a master cylinder 12 for generating hydraulic pressure by pressurizing the brake fluid according to the automatic operation of the brake pedal and the hydraulic pressure generated by the brake force generating unit 10. Spacing adjustment is provided in the pipe 30 to interconnect the brake unit 20 including the brake pad 22 for selectively pressing and braking the wheel drum 21 to adjust the distance between the wheel and the brake pad As a device, A cylinder member (200) installed in the pipe to have an inlet (40) through which the brake fluid flows from the braking force generating unit and an outlet (50) outflow of the brake liquid to the braking unit; And It is installed in the cylinder member to reciprocate according to the hydraulic pressure generated from the braking force generating unit to block the space inside the cylinder member into the inlet space portion 200A on the inlet side and the outlet space portion 200B on the outlet side, respectively. In the normal state in which the brake pad is not worn when the brake is operated, it moves forward in the cylinder member to transfer the hydraulic pressure applied to the inflow space portion to the outflow space portion, while the brake pad is worn out. The inflow space portion and the outflow space portion communicate with each other so that the brake fluid flows into the outflow space portion, thereby supplementing the hydraulic pressure corresponding to the degree of wear of the brake pads, thereby approaching the brake pads to the wheel drum, and then again the inflow space portion. Piston assembly for isolating and isolating the outlet space (30) 0); adjusting the distance between the wheel drum and the brake pad of the vehicle comprising a. The method of claim 1, wherein the piston assembly, A moving cylinder block 330 reciprocating in the cylinder member; A piston shaft 360 supporting the movable cylinder block to move to the yield point; Is installed inside the moving cylinder block, when the moving cylinder block is moved beyond the yield point to within the adjustment point, the inlet space 200A and the outlet space 200B is continuously isolated, the moving cylinder block is A valve means for flowing the brake fluid by communicating with the inflow space portion and the outflow space portion when moving to the adjustment point; And And a blocking means for blocking the brake fluid from flowing back from the outlet space to the inlet space, wherein the gap between the wheel drum and the brake pad of the vehicle is included. The method of claim 2, wherein the valve means, A yield cylinder block 350 inserted into the movable cylinder block to be slidable and inserted into the piston shaft 360 to reciprocate therein; An inflow sealing member 320b having a hollow portion and fixed to and supported by the yield cylinder block; The insertion portion 382 is coupled to the head of the moving cylinder block and is forcibly fitted into the hollow portion of the inflow sealing member, and an inlet valve hole communicating forward is formed on an outer circumferential surface of the insertion portion to the inflow sealing member. A valve member 380 opened and closed by; And And an elastic member 340 interposed between the yield cylinder block and the moving cylinder block to elastically bias the yield cylinder block forward. When the movable cylinder block reaches the adjustment point, the yield cylinder block is prevented from moving forward by the piston shaft, and the inlet valve hole is opened while the insertion portion of the valve member exits from the hollow portion of the inflow sealing member. Adjusting the gap between the wheel drum and the brake pad of the vehicle. The method of claim 3, It further comprises a support member 370 screwed to the head of the yield cylinder block while the locking jaw is formed coupled to the hollow portion of the inflow sealing member to securely support the inflow sealing member to the yield cylinder block. Characterized in that the gap between the wheel drum and the brake pad of the vehicle. 5. The apparatus of claim 4, wherein a hollow portion penetrating from the head portion of the support member to the tail portion is formed. The method of claim 3, The inlet valve hole is a gap between the wheel drum and the brake pad of the vehicle, characterized in that formed in the groove formed on the outer peripheral surface of the valve member. The method of claim 3, A communication hole is formed in the movable cylinder block and the yield cylinder block so that the brake fluid introduced into the inflow space of the cylinder member flows to the inside thereof. The method of claim 2, wherein the blocking means, A blocking member 390 coupled to the valve member and communicating with an inlet valve hole of the valve member and having an outlet valve hole leading to the outlet space part; And And a backflow sealing member (320c) coupled to an outer circumferential surface thereof to close the outlet valve hole of the blocking member. The method of claim 8, The outlet valve hole is the gap between the wheel drum and the brake pad of the vehicle, characterized in that formed in the groove formed on the outer peripheral surface of the blocking member. The method according to any one of claims 1 to 9, A passage 120 for communicating the inflow space portion and the outflow space portion of the cylinder member with each other; And Adjusting the gap between the wheel drum and the brake pad of the vehicle, characterized in that it further comprises a valve 130 for opening and closing the passage.