JPS5920760A - Air brake gear - Google Patents

Abstract

PURPOSE:To synchronize rises in pressure even when the quantities of air consumed by driven devices in each system are different from each other, by connecting two piping systems through a bypass passage in accordance with a movement of a movable body receiving pressures of the two systems in opposite directions. CONSTITUTION:A valve gear 27 is integrally provided at an air pressure part 20 of a booster 18, is provided with a valve hole 31 for communicating a connecting hole 28 connected to a brake valve and a connecting hole 30 connected to a pressure chamber of another booster 19 with each other, and a valve body 32 is movably fitted in the valve hole 31. A stem part 36 of the valve body 32 projects into a pressure chamber 37 so that it can make contact with a piston 39. In braking, when the quantity of air consumed by the brake gear in the system of the booster 18 is large, the rise of pressure in the pressure chamber of the booster 19 is larger than that in the booster 18. Therefore, a difference is generated between the pressures exerted on the valve body 32, and the valve body 32 is separated from a seat 35. Accordingly, the pressures in the pressure chambers of the two boosters 18, 19 are equalized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air brake device for a vehicle or the like.

BACKGROUND ART Conventionally, this type of return device is known in which compressed air from a compressed air source can be separately supplied from a main actuator to a driven device via two independent piping systems.

However, with these devices, when compressed air is supplied from the main actuator to at least two driven devices separately, if the amount of air required at the initial stage of operation of each driven device is different, the effective operating time of each actuator may be affected. This means that when the brakes are applied, for example, the front wheels start to apply first, and the rear wheels start to apply from the rear.In this case, there is a problem that the durability of the front brake system deteriorates. There is 0
In other words, if the amount of air required for the driven device belonging to one piping system to start operating effectively differs from that of the other piping system, the amount of air discharged from the main actuator to each piping system will vary per unit time. Since the amounts of hits are essentially the same,
Naturally, the larger the air consumption, the longer it takes to reach effective operation. In other words, in one system, when the driven device strokes to effective operation, when the volume increase in the pressure chamber caused by the movement of the movable body that receives compressed air is larger than that of the other, each driven device It would be fine if the amount of compressed air supplied to the main actuator differs depending on its size, but since the amount of air supplied from the main actuator to each driven device is approximately the same, it is equivalent to the increase in volume. In this case, the time required to reach a predetermined pressure is long, and on the other hand, “aif
If the i increment α is small, the required time is too short, and there is a problem that the start of applying the brake is different for each driven device. Furthermore, such problems are exacerbated by factors such as differences in the length of piping from the main actuator to each slave, and differences in the amount of wear on the brake linings or pads in the wheel brake system.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an air brake device that can perform braking of different systems at the same time. A bypass device is provided which includes movable bodies that receive the pressures of the two systems facing each other, and a bypass passage that connects the two systems according to the movement of the movable bodies.

That is, according to the present invention, the movable body receives the pressure in the two piping systems, detects the pressure difference in the two piping systems, and moves, thereby communicating the two piping systems with each other. Therefore, air is supplied to the side that requires a large amount of air, and the one that requires a small amount of air is supplied first, and the pressure in the two piping systems rises almost equally at the same time, so that the air consumption needle of each driven device increases. Even if they are different, the pressure rise can be synchronized.

Therefore, the start timing of the effective operation of each driven device can be made almost the same, making it possible to equalize the balance of the brakes when the vehicle brakes, making it possible to improve running stability, and improving the durability of each driven device. It is possible to average out and improve durability.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The air brake device of the present invention will be described in detail below based on illustrated examples.

FIG. 1 is a piping system diagram showing the entirety of an air brake device according to an embodiment of the present invention. FIG. 2 is a partial explanatory diagram showing a main part of FIG. 1 partially in cross section.

In the figure, the air brake device is indicated as 1 as a whole, and this device 1 includes an air tank 4 that receives air discharged from an air compressor (not shown) through a check valve 2 and a pipe 3. have. The air tank 4 is divided by a partition wall 5 into a first chamber 6 connected to the piping 3 and a second chamber 9 connected to the first chamber 6 via a check valve 7 and piping 8. Compressed air within a certain pressure range is stored in each chamber 6.9 of these air tanks 4, with a maximum pressure of less than 10 atm, for example 9.5 atm, and a minimum pressure of, for example, 7 atm. That's how it is.

The control section 12 of the lower half of the two-system brake pulp 11 is connected to the first chamber 6 via the piping 1o, and is arranged in the second chamber 91cl'I!
The control units 14 in the upper half of the two-system brake pulp 11 are connected to each other via the line 1B, and when the driver depresses the brake pedal 15, compressed air of approximately equal pressure is supplied to each control unit 12.14. It is designed to be discharged.

The control section 12.14 of the brake pulp 11 is connected to the pipe 16.
Air over hydraulic booster 18.
19 pneumatic parts 20 and 21, respectively. Hydraulic part 22.28fd of each booster 18.19: is connected to a wheel cylinder (not shown) of a wheel brake device, the hydraulic part 22 is connected to a brake device 24 of the front wheels and a brake device 25 of the rear wheels. to the wheel cylinder of
Further, the hydraulic pressure section 23 includes a brake device 26 for the rear and front wheels.
are connected to the respective wheel cylinders. In addition, each booster 18.19 is designed to generate hydraulic pressure proportional to the air pressure introduced into the pneumatic section 20.21 in the hydraulic section 22.2B, and transmit this to each wheel cylinder. be.

In particular, referring to FIG. 2, a valve system #27 is integrally provided in the pneumatic portion 20 of the booster 18. The valve device 27 communicates with a connection hole 28 to which the pipe 16 is connected and a connection hole 30 to which a pipe 29 connected to a pressure chamber (not shown) in the pneumatic part 21 of another booster 18 is connected. A valve hole 31 is provided in the valve hole 31, and a valve body 82 is movably inserted into the valve hole 31. The valve body 32 is pushed to the left by a light tension valve spring 83 so as to close the connection hole 30, and a seat 85 is pressed onto a seat 34 provided on the end wall of the valve hole 31. The shaft portion 36 provided on the right side of the other valve body 32 is
The hole 38 provided from the valve hole 31 to the pressure chamber 37 in the pneumatic part 2o is penetrated through 3B'rL, and protrudes into the pressure chamber 87, so that it can come into contact with the pneumatic piston 89 that partitions the pressure chamber 37. ing. 4o is a return spring for the pneumatic piston 39. The valve body 82 is capable of sliding along the inner periphery of the valve hole 81, and has a plurality of notches 41 formed for air circulation, and also prevents contact between the seat 35 and the seat 84. The effective pressure receiving area for compressed air on the side of the connection hole 28 and the effective pressure receiving area for compressed air on the side of the connection hole 30 are substantially equal to each other, with the boundary between the two sides. 42 is an 0 ring.

In the above description, since the brake valve 111, booster 18, 19, etc. are well known, detailed description thereof will be omitted. Functions in the above examples will be described below.

Assuming that the brake is not applied now, the brake pulp 11 and the pedal 15 are not depressed, so each control section 12.14 cuts off communication between the pipes 10 and 13 and the pipe 16. .17 is connected to the outside air 0 Therefore, the pressure inside the pipes 16 and 17 and the pneumatic parts 20 and 21 are all reduced to the same pressure as the outside air 9, and the hydraulic part 22
, 28 has also been released. At this time, the valve device 27
In this case, the seat 85 is seated on the seat 34 by the tension of the valve spring '83, and is reliably maintained in the seated state by the tension of the return spring 40 via the pneumatic piston 39.

In this state, when the brake pedal 15 is depressed, compressed air is supplied from the first chamber 6 to the pneumatic section 2 via the control section 12.
In addition, compressed air is supplied to the pneumatic part 21 from the @2 chamber 9 via the control unit 14.

The compressed air supplied to the pneumatic section 21 reaches the connection hole 30 via the piping 29 and applies pressure in the direction of separating the valve body 32 from the seat 84. The compressed air conversely exerts pressure to press the valve body 82 toward the seat 34.

It is assumed that in this state, the pistons of the respective pneumatic parts 20 and 21 begin to move and make a certain amount of stroke.

Then, the volume of the pressure chamber 37 (the other not shown) in the pneumatic part 20.21 increases, and the brake pulp 1
Compressed air discharged from 1 is sequentially supplied into the pressure chamber.

In the initial stage of operation of each pneumatic portion 20, 21, both have not yet reached effective operation, so a large pressure difference does not yet occur in the pressure received by the valve body 82, and the valve body 32 does not move.

After that, since the booster 18 is connected to the brake device 24.25 for 2114 II, the operation of each wheel cylinder causes a gap between the drum and the lining or between the drum and the lining.
The amount of liquid consumed to close the gap between the disc and the pad is relatively large, and on the other hand, the booster 19 has -
Since the brake device 26 for each shaft is connected, the amount of fluid consumed as described above is small. Since they are equal, the pressure rise in the pneumatic part 20 is smaller than the pressure rise in the pneumatic part 21,
Therefore, a difference occurs between the two systems of air pressure acting on the valve body 32, and this pressure difference causes the valve body 32 to move so as to move the seat 35 away from the seat 34 against the biasing force of the valve spring 33. The interiors of the two pneumatic parts 20 and 21 communicate with each other, and from the pneumatic part 21, which quickly becomes high pressure, to the pneumatic part 20 via the piping 29, valve hole 31, etc. In other words, part of the air discharged from the brake pulp 11 is supplied to the pneumatic part 20 until the differential pressure between the pneumatic part 20 and the pneumatic part 21 becomes small. For example, the pressure in the pneumatic part 20 is rapidly reduced to the same pressure as the pressure in the pneumatic part 21. It continues to rise.

This allows the pneumatic sections 20.21 to have equal pressures so that their effective operations begin at the same time, although they require different amounts of air before their effective operation begins. .2+ is not only equalized, but also the free stroke of the wheel brake device 24.25 on the booster 18 side is rapidly performed. Effective operation at 26 will occur at approximately the same time.

Therefore, since the brakes begin to be applied on all wheels almost simultaneously, a predetermined braking force can be obtained on each wheel, and the braking force between the wheels can be balanced, increasing running stability.

After this, from the brake pulp 11 each pneumatic section 20.
When a sufficient amount of air is supplied to the brake pedal 21, the pressure increases to the input pressure from the brake pedal 15 and the desired brake is applied.At this time, the valve system @27 is connected to both pneumatic parts. When the pressure difference within 20.21 becomes sufficiently small, the valve spring 33 moves the seat 35 to a position where it is seated on the seat 34.

When the foot is removed from the brake pedal 15 in order to release the brake, the compressed air supplied to the pneumatic part 20.21 is discharged to the outside air via the control part 12.14 and the brake is not applied. Return to the state where there is no.

In these above-described embodiments, the air consumption amounts for the effective operation of the boosters 1g and 19 are different, and the valve device 27
Since compressed air can be supplied from the booster 19 side to the booster 18 side, effective operation can be started almost simultaneously. Furthermore, in the above example, the following effects are achieved. In other words, if compressed air is supplied to the pneumatic portion 21 but leaks due to a malfunction or the like, the valve body 32 prevents the air from being supplied to the pneumatic portion 20. Since the compressed air is then applied in the direction of holding the seat, the two pneumatic parts 20 and 21 do not come into contact with each other, and no braking occurs. Conversely, if compressed air is supplied to the pneumatic portion 20 but leaks due to damage to the O-ring 42, the valve body 32
Since it is held in that position by the action of the return spring 40, movement in the direction of leaving the seat is prevented, and no braking occurs. In other words, the valve device 27 that connects the two systems has a so-called fail-safe function that blocks the function of one system when it is abnormal.

As described above, the above-mentioned examples have various effects, but the present invention is not limited to the illustrated examples and can be implemented.

That is, for example, in the illustrated example, the air consumption amount until the booster 18 becomes effective is larger than that of the booster 19, but if it is unclear which one is larger, the air consumption of the piping 29
, an example in which another set of valve devices t27 is provided in the opposite direction instead of the − group, an example in which the valve spring 38 is abolished, an example in which the valve device 27 is a gradient/jar type switching valve, and a booster is used as the driven device. , examples targeting relay pulp, air chambers, etc., and examples where the valve device is separate from the driven device and installed in the middle of piping.

In addition, if the effective operation start pressure differs depending on the driven device,
The opening conditions of the valve device may be set in consideration of this differential pressure.

In addition to the illustrated example, examples of piping systems to which the present invention can be applied include so-called front and rear piping systems between the front and rear wheels, piping systems commonly known as X piping and J piping, but in short: Regardless of the combination, the present invention is applicable to anything that has two piping systems.As described above, various modifications are possible, and various modifications are possible in addition to those mentioned above. can be changed.

As is clear from the above description, according to the present invention, there is provided an air brake device that can perform braking of two different systems simultaneously.

[Brief explanation of the drawing]

Fig. 1 is a piping system diagram showing the entire air brake device that is an embodiment of the present invention, and Fig. 2 is a partial explanatory diagram showing a part of the main part of Fig. 1 in cross section.・Air brake device 27... Valve device 28... Connection hole 29...
Piping 30... Connection hole 31... Valve hole 32...
Valve body patent applicant: Nippon Kogyo Brake Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] In an air brake device in which compressed air from a compressed air source can be supplied from a main actuator to a driven device separately via two independent piping systems, a movable body receives pressure in the two piping systems in opposing directions. and a bypass passage that connects the two systems according to the movement of the movable body.