KR102017201B1 - Common breaking device for vehicle - Google Patents

Abstract

The present invention relates to a common vehicle brake device. The common vehicle brake device includes: an elastic spring inserted into an insertion groove formed on one side of an axle housing in a horizontal direction, and including an axle driving shaft rotated for driving by receiving power from an axle input shaft connected with an engine, an axle hub installed at both ends of the axle driving shaft to be equipped with a driving wheel, an axle housing placed at a distance from the outer edge of the axle driving shaft to protect the axle driving shaft, and an axle hub housing placed at a distance from the outer edge of the axle hub to protect the axle hub; a parking brake piston moved by oil pressure and the tension of the elastic spring as far as a predetermined distance; a block part fixed to the inner surface of the axle housing to limit a movement distance for the parking brake piston; a service brake piston placed on one side of the block part and moved by oil pressure and the parking brake piston as far as a predetermined distance; and a common brake pack attached to or detached from the service brake piston and combined with the axle driving shaft through a coupling, and in which a disc plate and a friction plate are arranged alternately. Therefore, the common vehicle brake device is capable of preventing a parked vehicle from being moved because of a gap occurring in a parking brake.

Description

Common breaking device for vehicle

The present invention relates to a common brake apparatus for a vehicle, and more particularly, to a common brake apparatus for a vehicle in which a service brake and a parking brake are commonly used in construction equipment and an industrial vehicle.

In general, a brake device for a construction vehicle such as a commercial vehicle, a forklift, a wheel loader, and the like and an industrial vehicle, a service brake device for braking when driving and a parking brake device for braking when parking are used.

Conventionally, the service brake device is mounted on the axle hub side to which both ends of the drive shaft are connected, and the parking brake device is mounted on the axle input shaft that inputs power to the drive shaft.

As described above, when the service brake device is conventionally mounted on the axle hub side and the parking brake device is mounted on the axle input shaft, since the service brake device and the parking brake device are configured separately, the number of parts and the number of assembly operations are increased so that the overall There is a disadvantage that the productivity is lowered, the production cost is increased.

In addition, in the case of the parking brake device mounted on the axle input shaft side, the vehicle may be shaken by the gear backlash generated from the axle hub shaft to the axle hub through the axle drive shaft during operation for vehicle parking. There was a problem that the sense of stability is lowered, the sensitivity quality during parking braking is greatly reduced.

Therefore, recently, in order to solve the above problems, as disclosed in Korean Patent Laid-Open Publication No. 10-2015-0089255, a construction brake and a common brake device for an industrial vehicle having a service brake device and a parking brake device have been proposed.

Hereinafter, the configuration of a conventional brake device for construction equipment and industrial vehicles will be described.

1 and 2 are conventional brakes for construction equipment and industrial vehicles according to the prior art, Figure 1 is a cross-sectional view showing a service brake operating state, Figure 2 is a cross-sectional view showing a parking brake operating state.

In FIG. 1 and FIG. 2, reference numeral 20 denotes an axle drive shaft that rotates for driving by receiving power from an axle input shaft connected to an engine side, and driving wheels are mounted at both ends of the axle drive shaft 20. The axle hub 22 is connected.

In addition, an axle housing 24 for protecting the axle drive shaft 20 is disposed at an outer diameter portion of the axle drive shaft 20, and an axle hub housing for protecting the axle hub at an outer diameter portion of the axle hub 22 ( 26 are spaced apart.

In addition, a service brake for braking during driving is provided between an outer diameter portion of both ends of the axle drive shaft 20, an axle housing 24 surrounding the axle drive shaft 20, and an axle hub housing 26 surrounding the axle hub 22. There is provided a common brake device 100 in which the device and the parking brake device for braking at the same time are shared.

At this time, as one configuration of the common brake device 100, the common brake pack 110 in which the disc plate and the friction plate are alternately arranged is mounted on the outer diameter portions of both ends of the axle drive shaft 20.

In addition, a service brake piston 120 is disposed at an inner position of the common brake pack 110 and pressurizes the common brake pack 110 by hydraulic pressure provided to obtain a braking force while driving. have.

At this time, in order to supply the hydraulic pressure for pressurizing the service brake piston 120 toward the common brake pack 110 to the axle housing 24, the hydraulic supply port for the service brake communicating with the inner surface of the service brake piston 120 is formed through. do.

That is, as a passage for supplying hydraulic pressure for pressing the service brake piston 120 toward the common brake pack 110 at a position coinciding with the inner surface side of the service brake piston 120 of the axle housing 24, the service brake piston ( The hydraulic pressure supply port 160 for the service brake communicating with the inner surface of the 120 is formed to pass through.

Therefore, when the hydraulic pressure is supplied through the service brake hydraulic supply port 160, the service brake piston 120 moves toward the common brake pack 110, so that the disk plate and the friction plate of the common brake pack 110 are brought into close contact with each other. By applying pressure, braking of the service brake device is achieved.

In addition, when the hydraulic pressure applied to the service brake piston 120 is released, the service brake piston 120 is provided with a return means using an elastic force so that the service brake piston 120 returns to its original position.

That is, the return means using the elastic force penetrates the inner diameter portion of the service brake piston 120 and is fastened to the axle housing 24, the head of the bolt 132 and the outer surface of the service brake piston 120. It is composed of a service brake spring 130 which is arranged to be compressible.

Therefore, when the service brake piston 120 presses the disk plate and the friction plate of the common brake pack 110 in close contact with each other, the service brake spring 130 is compressed, while the service brake hydraulic supply port 160 is provided. When the applied hydraulic pressure is released, the service brake piston 120 returns to its original position (non-braking position) by the elastic restoring force of the service brake spring 130.

On the other hand, the parking brake piston 140 is disposed in the inner diameter portion of the axle housing 24 while being outside the common brake pack 110, and the parking brake piston 140 has a hydraulic release to obtain a braking force when parking. Pressing the common brake pack 110 by the elastic restoring force of the parking brake spring 150 provided together.

At this time, the parking brake spring 150 is arranged to be compressible between the outer surface of the parking brake piston 140 and the axle hub housing 26.

Preferably, the spring seating recess into which both ends of the parking brake spring 150 are inserted into the outer surface of the parking brake piston 140 and the inner surface of the axle hub housing 26 to prevent the parking brake spring 150 from being separated. 152 is formed.

In addition, the parking brake is applied to a position corresponding to the inner surface of the parking brake piston 140 of the axle housing 24 to apply hydraulic pressure for separating the parking brake piston 140 from the common brake pack 110 when the parking brake is released. The parking brake hydraulic pressure supply port 170 communicating with the inner surface of the piston 140 is formed to pass through.

Therefore, when the hydraulic pressure is applied to the parking brake hydraulic pressure supply port 170, the parking brake piston 140 is separated from the common brake pack 110 by the hydraulic pressure at this time while compressing the parking brake spring 150. It is moved toward the axle hub housing 26.

On the other hand, when the hydraulic pressure is released to the hydraulic pressure supply port for the parking brake, the parking brake piston 140 presses the common brake pack 110 by the elastic restoring force of the compressed parking brake spring 150, thereby Braking is achieved.

Looking at the operation relationship for the conventional construction equipment and the industrial brake device for an industrial vehicle made as described above are as follows.

Service brake actuation (see Fig. 1)

First, the hydraulic pressure is applied through the service brake hydraulic pressure supply port 160 of the axle housing 24.

Therefore, the service brake piston 120 is moved toward the common brake pack 110 by the hydraulic pressure supplied through the hydraulic brake opening 160 for the service brake, so that the disk plate and the friction plate of the common brake pack 110 are brought into close contact with each other. By applying pressure, braking of the service brake device is achieved.

At this time, the parking brake is maintained in the brake release state (non-braking state) when the vehicle is running and when the service brake is operated.

That is, hydraulic pressure is also applied to the parking brake hydraulic pressure supply port 170 so that the parking brake piston 140 is separated from the common brake pack 110 and the compression of the parking brake spring 150 is directed toward the axle hub housing 26. In the moved state, that is, the state is moved to the parking brake brake release position.

Of course, when the hydraulic pressure supplied through the service brake hydraulic supply port 160 is released, the service brake piston 120 returns to its original position (non-braking position) by the elastic restoring force of the service brake spring 130.

Parking brake operation (see Fig. 2)

First, the hydraulic pressure applied to the parking brake hydraulic pressure supply port 170 is released.

When the hydraulic pressure is released to the parking brake hydraulic supply port 170 in this way, the parking brake piston 140 presses the common brake pack 110 by the elastic restoring force of the compressed parking brake spring 150, thereby parking the vehicle. Braking of the brake device takes place.

At this time, the hydraulic pressure is also maintained in the service brake hydraulic supply port 160, the service brake piston 120 is returned to its original position (non-braking position) by the elastic restoring force of the service brake spring 130 State is maintained.

However, the above-described conventional brake device for construction equipment and industrial vehicles includes a service brake device and a parking brake device between an outer diameter portion of both ends of the axle drive shaft, an axle housing surrounding the axle drive shaft, and an axle hub housing surrounding the axle hub. Install the integrated brake system integrated into one, but the service brake device and the parking brake device are disposed opposite to each other with the common brake pack interposed therebetween to pressurize in both directions. When operating the parking brake, when the parking brake piston is moved by the elastic restoring force of the parking brake spring to come into contact with the common brake pack, the vehicle may be pushed backward by the play.

That is, in a state where the vehicle is parked on an inclined hill or the like, as the driver presses the brake pedal to operate the service brake device, the service brake piston presses the common brake pack toward the parking brake device by hydraulic pressure. And the common brake pack is moved toward the parking brake device as a whole. At this time, the parking brake piston is in a state in which the parking brake piston is compressed by hydraulic pressure.

In this state, when the parking brake device is activated and the service brake is deactivated at the same time, the hydraulic pressure is leaked, and the parking brake piston is moved in contact with the common brake pack by the elastic restoring force of the parking brake spring. At this time, the service brake piston and the common brake pack are also moved in the direction of the service brake device, so that the time for the parking brake piston to contact the common brake pack is delayed and the vehicle is pushed back by the delay time. There was this.

Korea Patent Publication No. 10-2015-0089255 (2015.08.05.)

Accordingly, the present invention has been made in order to solve the above problems, the technical problem to be solved by the present invention, by arranging the parking brake device and the service brake device in one direction of the common brake pack sequentially, hill It is to provide a common brake device for a vehicle to prevent the vehicle from sliding due to the play even when the vehicle is parked at an inclined position such as the driving brake.

In addition, another technical problem to be solved by the present invention, by sequentially placing the parking brake device and the service brake device in one direction of the common brake pack, it is possible to greatly improve the overall productivity by improving the assembling It is to provide a common brake device for a vehicle.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

The common brake device for a vehicle according to an exemplary embodiment of the present invention for solving the above problems is provided with axle drive shafts which are driven to rotate for driving while receiving power from an axle input shaft connected to an engine, and are installed at both ends of the axle drive shaft. An axle hub on which a wheel is mounted, an axle housing disposed to be spaced apart from an outer diameter portion of the axle drive shaft to protect the axle drive shaft, and an axle hub housing disposed to be spaced apart from an outer diameter portion of the axle hub to protect the axle hub, An elastic spring embedded in an inlet groove formed in a horizontal direction on one side of the axle housing; Parking brake piston is moved by a predetermined interval by the tension and hydraulic pressure of the elastic spring; A block portion fixedly installed on an inner wall surface of the axle housing to limit a movement interval of the parking brake piston; A service brake piston disposed at one side of the block part and moved by a predetermined interval by the parking brake piston and hydraulic pressure; And a common brake pack that is in close or in close contact with the service brake piston and coupled to the axle drive shaft by a coupling, in which a disk plate and a friction plate are alternately arranged.

In this case, the parking brake piston is in contact with the elastic spring, the first end disposed between the elastic spring and the block portion, and is formed to extend in a direction crossing from one side of the first end to the service And a second end that engages the brake piston.

In addition, a first fluid inflow space may be formed between the parking brake piston and the block portion, and a second fluid inflow space may be formed between the service brake piston and the axle housing.

At this time, when the service brake device and the parking brake device are deactivated to drive the vehicle, the fluid in the second fluid inflow space flows out, the fluid flows in the first fluid inflow space, and the parking brake piston The axle drive shaft may be freely rotated as the parking brake piston and the service brake piston are spaced apart from the common brake pack while compressing the elastic spring, thereby moving in the opposite direction to the common brake pack.

Meanwhile, when the service brake device and the parking brake device are operated for stopping and parking the vehicle, fluid flows into the second fluid inflow space, fluid in the first fluid inflow space flows out, and the parking brake piston The service brake piston is in close contact with the common brake pack as the parking brake piston and the service brake piston move toward the common brake pack by the elastic restoring force of the elastic spring. It is possible to limit the rotation of the axle drive shaft.

Here, when the vehicle is parked by the operation of the service parking brake, when the parking brake is operated, the fluid remains in the second fluid inflow space as it is, and the fluid is discharged in the first fluid inflow space. As the state is maintained, the parking brake piston is moved in the direction of the service brake piston by the elastic restoring force of the elastic spring, thereby maintaining the service brake piston in close contact with the common brake pack to operate the parking brake. State can be achieved.

Other specific details of the invention are included in the detailed description and drawings.

According to the common brake device for a vehicle according to an embodiment of the present invention, the parking brake device and the service brake device are sequentially arranged in one direction of the common brake pack, so that the vehicle is parked at an inclined position such as a hill to operate the parking brake. Even in the state, it is possible to prevent the vehicle from rolling due to the occurrence of play, thereby providing an effect of greatly improving reliability.

In addition, according to the common brake device for a vehicle according to an embodiment of the present invention, by sequentially placing the parking brake device and the service brake device in one direction of the common brake pack, the overall productivity is greatly improved as the assembly is improved May also be provided.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a cross-sectional view showing a service brake operating state as a common brake device for construction equipment and industrial vehicles according to the prior art.
Figure 2 is a cross-sectional view showing a parking brake operating state as a common brake device for construction equipment and industrial vehicles according to the prior art.
3 is a cross-sectional view showing the overall configuration of a common brake device for a vehicle according to an embodiment of the present invention.
4 is an enlarged cross-sectional view of the main portion of FIG. 3;

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only the embodiments of the present invention make the disclosure of the present invention complete and the general knowledge in the technical field to which the present invention belongs. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Thus, in some embodiments, well known process steps, well known structures and well known techniques are not described in detail in order to avoid obscuring the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, including and / or comprising means not to exclude the presence or addition of one or more other components, steps, and / or actions other than the components, steps, and / or actions mentioned. Used as. And “and / or” includes each and all combinations of one or more of the items mentioned.

In addition, embodiments described herein will be described with reference to perspective, cross-sectional, side and / or schematic views, which are ideal illustrative views of the present invention. Accordingly, shapes of the exemplary views may be modified by manufacturing techniques and / or tolerances. Therefore, the exemplary embodiments of the present invention are not limited to the specific forms shown, but include changes in forms generated according to manufacturing processes. In addition, each component in the drawings shown in the embodiment of the present invention may be shown to be somewhat enlarged or reduced in consideration of the convenience of description.

Hereinafter, a common brake device for a vehicle according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a cross-sectional view showing the overall configuration of a common brake device for a vehicle according to an embodiment of the present invention, Figure 4 is an enlarged cross-sectional view of the main part of FIG.

3 and 4, the common brake device for a vehicle according to an embodiment of the present invention, the axle drive shaft 300 that is driven to rotate for driving by receiving the power of the axle input shaft connected to the engine side, and the axle The axle hub 310 is installed at both ends of the drive shaft 300 and the driving wheel is mounted, and the axle housing 320 and the axle are disposed to be spaced apart from the outer diameter portion of the axle drive shaft 300 to protect the axle drive shaft 300. It may be configured to include an axle hub housing 350 disposed to be spaced apart from the outer diameter portion of the hub 310 to protect the axle hub 310.

In addition, the common brake device for a vehicle according to an embodiment of the present invention, the elastic spring 324 and the hydraulic and elastic spring 324 of the inlet groove 322 formed in a horizontal direction on one side of the axle housing 320 The parking brake piston 326, which is moved by a predetermined interval by tension, and the block portion 328 fixed to the inner wall surface of the axle housing 320 to limit the movement interval of the parking brake piston 326, and The service brake piston 332 disposed on one side of the block 328 and moved by a predetermined distance by the parking brake piston 326 and the hydraulic pressure, and the service brake piston 332 are in close or in close contact with each other and are coupled to each other. Coupled with the axle drive shaft 300, the disk plate and the friction plate may be configured to further include a common brake pack 340 is alternately arranged.

Here, the parking brake piston 326 is in contact with the elastic spring 324 and is disposed between the elastic spring 324 and the block portion 328 and a first end 326a of the first end 326a. The second end 326b may be formed to extend in a direction crossing from one side and may be coupled to the service brake piston 332.

At this time, a first fluid inflow space 330 is formed between the first end 326a of the parking brake piston 326 and the block portion 328, and the first fluid inflow space 330 is a parking brake. Fluid may be introduced or discharged from the hydraulic supply port (not shown), and an operation relationship thereof will be described later in detail.

In addition, a second fluid inflow space 334 is formed between the service brake piston 332 and the axle housing 320, and the hydraulic fluid supply port for the service brake (not shown) is used as the second fluid inflow space 334. Fluid may be introduced or discharged from the air, and an operation relationship thereof will be described later in detail.

As described above, the vehicle common brake apparatus according to the embodiment of the present invention, the service brake piston 332 and the parking brake piston (332) continuously in one direction of the common brake pack 340 in the axle housing 320 ( 326 and the elastic spring 324 are sequentially arranged, the service brake piston 332 is in close contact with the common brake pack 340 in one direction during the service brake operation and the parking brake operation, the play is generated The phenomena due to the rolling can be prevented, and the operation relations thereof will be described as follows.

When driving

While the vehicle is running, fluid in the second fluid inflow space 334 between the service brake piston 332 and the axle housing 320 flows out through the hydraulic supply port for the service brake, and conversely, The fluid is supplied to the first fluid inflow space 330 formed between the first end portion 326a and the block portion 328 through the hydraulic pressure supply port for the parking brake, so that the parking brake piston 326 opens the elastic spring 324. While compressing, it moves in the opposite direction to the common brake pack 340.

Therefore, the service brake piston 332 coupled with the second end 326b of the parking brake piston 326 also moves toward the block portion 328, whereby the axle is spaced apart from the common brake pack 340. The drive shaft 300 is freely rotatable to travel.

Service brake operation

First, when the brake pedal is pressed while the vehicle is driving, the hydraulic pressure is applied through the service brake hydraulic pressure supply port of the axle housing 320, and thus, a second fluid between the service brake piston 332 and the axle housing 320 is provided. As the fluid is supplied to the inflow space 334, the service brake piston 332 presses the disk plate and the friction plate of the common brake pack 340 in close contact with each other, thereby braking the service brake device.

At this time, the fluid filled in the first fluid inlet space 330 formed between the first end 326a of the parking brake piston 326 and the block portion 328 is discharged through the hydraulic supply port for parking brake. Accordingly, by moving the parking brake piston 326 in the direction of the service brake piston 332 by the elastic restoring force of the elastic spring 324, the service brake piston 332 may further improve adhesion to the common brake pack 340. Can be.

Parking brake works

The parking brake is operated when the vehicle is stopped, that is, while the service brake is in operation. When the parking brake is operated after the service brake is operated to stop the vehicle, the parking brake is operated with the service brake and the second fluid inflow space ( By maintaining the hydraulic pressure between the 334, the parking brake state is achieved.

That is, when the parking brake is actuated, the fluid remains in the second fluid inflow space 334 between the service brake piston 332 and the axle housing 320, and the parking brake piston 326 is removed. The first fluid inflow space 330 formed between the first end portion 326a and the block portion 328 maintains a state in which the fluid is discharged. The parking brake piston 326 is formed by the elastic restoring force of the elastic spring 324. By moving () in the direction of the service brake piston 332, the service brake piston 332 is maintained in close contact with the common brake pack 340 to maintain a braking state.

Therefore, the common brake device for a vehicle according to an exemplary embodiment of the present invention is applied to the elastic restoring force of the elastic spring 324 even when the parking brake device is operated while the service brake device is first operated to park the hill on the inclined vehicle. As a result, the parking brake piston 326 and the service brake piston 332 continuously move in one direction so that the service brake piston 332 continuously presses the common brake pack 340. This non-occurring effect can be provided.

In addition, the vehicle common brake apparatus according to an embodiment of the present invention, the elastic spring 324, the parking brake piston 326, the block portion 328, and the service brake piston 332 from the inside of the axle housing 320. And the common brake pack 340 are sequentially inserted and assembled, so that the service brake device and the parking brake device are installed with the common brake pack 340 interposed therebetween, so as to fit the clearance therebetween. By simplifying the assembly, the effect of greatly improving the productivity can also be provided.

Those skilled in the art will appreciate that the present invention can be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

300: axle drive shaft 310: axle hub
320: axle housing 322: inlet groove
324: elastic spring 326: parking brake piston
326a: first end 326b: second end
328: block portion 330: first fluid inflow space
332: service brake piston 334: second fluid inlet space
340: common brake pack 350: axle hub housing

Claims (7)

An axle drive shaft which is driven to receive rotation of the axle input shaft connected to the engine and rotates for driving, an axle hub installed at both ends of the axle drive shaft and mounted with a driving wheel, and spaced apart from an outer diameter portion of the axle drive shaft It includes an axle housing for protecting the axle drive shaft and the axle hub housing spaced apart from the outer diameter portion of the axle hub to protect the axle hub,
An elastic spring embedded in an inlet groove formed in a horizontal direction on one side of the axle housing;
Parking brake piston is moved by a predetermined interval by the tension and hydraulic pressure of the elastic spring;
A block portion fixedly installed on an inner wall surface of the axle housing to limit a movement interval of the parking brake piston;
A service brake piston disposed at one side of the block part and moved by a predetermined distance by the parking brake piston and hydraulic pressure; And
It further comprises a common brake pack in close or in close contact with the service brake piston and coupled to the axle drive shaft by a coupling, the disk plate and the friction plate alternately arranged,
And a first fluid inflow space is formed between the parking brake piston and the block portion, and a second fluid inflow space is formed between the service brake piston and the axle housing.
The method of claim 1,
The parking brake piston,
A first end in contact with the elastic spring and disposed between the elastic spring and the block portion;
And a second end formed to extend in a direction crossing from one side of the first end and coupled to the service brake piston.
delete delete The method of claim 1,
When the service brake device and the parking brake device are deactivated to drive the vehicle,
Fluid in the second fluid inlet space flows out, and fluid is introduced into the first fluid inlet space,
The parking brake piston moves in the opposite direction to the common brake pack while compressing the elastic spring, so that the axle drive shaft is freely rotated as the parking brake piston and the service brake piston are spaced apart from the common brake pack. Brake system for vehicles.
The method of claim 1,
When operating the service brake system and the parking brake system for stopping and parking the vehicle,
Fluid flows into the second fluid inflow space, fluid in the first fluid inflow space flows out,
The parking brake piston is moved in the direction of the common brake pack by the elastic restoring force of the elastic spring. As the parking brake piston and the service brake piston move in the direction of the common brake pack, the service brake piston is moved to the common brake pack. In close contact with the pack to limit the rotation of the axle drive shaft, the vehicle common brake device.
The method of claim 6,
When the vehicle is parked by the operation of the service parking brake and then the parking brake is actuated,
As the fluid is maintained in the second fluid inflow space as it is, and the fluid is discharged in the first fluid inflow space as it is, the parking brake piston is driven by the elastic restoring force of the elastic spring. And maintaining the state in which the piston is moved in the piston direction to maintain the service brake piston in close contact with the common brake pack, thereby achieving a parking brake operating state.

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