JPH0239893Y2 - - Google Patents

Description

[Detailed description of the invention] The invention is an anti-skid device for both wheel brakes installed on one wheel of a motor vehicle, which comprises one 3-port 2-position main directional control valve connected to the brake conduit. and the outlets of the 3-port 2-position main directional control valves each lead to a respective brake cylinder by a branch conduit, so that the 3-port 2-position main directional control valve The brake cylinder is commonly controlled, and at least one valve is configured to switch the operating force of the 3-port 2-position main directional control valve.
A front control valve is provided, the front control valve comprising:
When the wheels tend to lock, it is controlled to bring the 3-port 2-position main directional control valve to a pressure reducing position, and the one branch conduit is connected to the pre-controlled 3-port 2-position main directional control solenoid valve. one unique 2-port 2-position main directional control valve is provided in the other branch conduit, operated by a pre-controlled 3-port 2-position directional control solenoid valve; A port 2-position main directional control valve is provided, and when a skid occurs, when switching the 3-port 2-position main directional control valve to a pressure reduction position by the front control valve, the two 2-port 2-position main directional control valves are Of the control valves, the 2-port 2-position main directional control valve assigned to the one wheel that does not have a tendency to lock is closed to maintain the pressure in the brake cylinder assigned to this one wheel. In this state, the 3-port 2-position main directional control valve and both 2-port 2-position main directional control valves cooperate through one control logic circuit so that the brake cylinder assigned to the other wheel is anti-lock controlled. of the type adapted to operate to control the pressure within each brake cylinder.

BACKGROUND OF THE INVENTION An antiskid device of the type described above is already known from German Patent Application No. 2625502 (Kokukoku-Sho 63-29640).
According to this known anti-skid device, both wheel brakes of an axle are controlled by directional control valves, so that during the control process there are different brake pressures adapted to the road conditions, and the individual wheel brakes are controlled by directional control valves. The device is not expensive with respect to valves or evaluation circuits. Such known antiskid devices are for both pneumatically operated wheel brakes on one axle. When operating the brake system using compressed air, the compressibility of the compressed air allows a significantly larger amount of air to be conveyed, resulting in brake control with fewer errors, but the disadvantage is that the response is slow. .

Problem to be solved by the invention The problem of the invention is to improve the known anti-skid device in such a way as to eliminate the aforementioned disadvantage of slow response while maintaining the advantages that the known anti-skid device has. It is.

Measures taken to solve the problem The measures taken to solve the above problem are 3.
The 2-way port 2-way main directional control valve and the 2-way 2-way main directional control valve are configured as a pressure control valve unit, and the pressure control valve unit is designed for hydraulically operating the brakes of at least two motor vehicle wheels. A unit consisting of a pre-control cylinder and a master cylinder is provided between the brake cylinder and the brake cylinder.

Effects of the invention The advantage achieved by the invention is that it provides a faster response compared to purely pneumatically operated braking systems. Moreover, since the pressure control valve unit of the anti-skid device is not hydraulically operated but remains pneumatically operated, there is no need for additional check valves or low-tolerance throttles.

Example The invention will be explained below with reference to the illustrated embodiments.

A compressed air storage container 1 is connected to a brake valve 2, which initiates the operation of two brake cylinders 3,4. Both brake cylinders 3, 4
are two wheels 5, 6 assigned to a common axle 7
operate the wheel brakes.

In the conduits 8, 9, 10 leading from the brake valve 2 to the brake cylinders 3, 4 there are 3-port 2-position directional solenoid valves 11, 12, 1 as three pre-control valves.
3 are arranged, the three-port two-position directional control solenoid valve controlling one branch conduit 14, 15, 16 respectively to the three main directional control valves. Of the main directional control valves mentioned above, the central main directional control valve is connected directly to line 8 and thereby directly to brake valve 2 . This main directional control valve is formed as a 3-port 2-position main directional control valve 18,
Furthermore, this is a 2 port 2 position main directional control valve 1
7, 19 to control one branch line 20, 21 in each case to two further main directional control valves.

In this manner, the 3-port 2-position main directional control valve 18 is provided in the conduits 8, 9, 10 leading to the brake cylinders 3, 4, and the 3-port 2-position main directional control valve 18 is led in the direction to the brake cylinder 3 or 4 via a respective branch line 20 or 21 behind the branch line 20 or 21, and a two-port, two-position main directional control valve 17 or 19 which is specific to the branch line 20 or 21. It is well known that this is provided.

Three pre-control directional control solenoid valves 11, 12, 13
The three main directional control valves 17, 18, 19 are combined into one pressure control valve unit 22. The pressure control valve unit 22 has four valve seats 23, 24, 2.
4' and 25 are provided, and the passage formed by the valve seat is opened and closed by diaphragm members 26, 27, 28 as valve closing members. Front control 3-port 2-position directional control solenoid valve 11, 12,
Branch conduits 14, 15, 16 for 13 open into working chambers 29, 30, 31 which are delimited by diaphragm elements 26, 27, 28. A brake conduit 8 is connected to the valve inlet 32 . A valve inlet 32 communicates with the valve seat 24' of the 3-port, 2-position main directional control valve 18, and the diaphragm member 27 of the 3-port, 2-position main directional control valve 18 includes:
A rod 33 passing through the valve seat 24 is fixed. A rod 33 has a closing member 3 as a working member at its other end.
4 is supported. The closing member 34 together with a valve seat 35 fixed to the housing forms the outlet valve 24 , 34 of the 3/2-position main directional control valve 18 which controls the fresh air connection 36 .

In front of each brake cylinder 3, 4, a front control cylinder 39 is connected to the conduit 9 or 10.
and a hydraulic master cylinder 40, or a unit 3 consisting of a pre-control cylinder 39' and a hydraulic master cylinder 40'.
8 is provided.

During normal braking, a free brake line passage leads from the brake valve 2 via the brake lines 8, 9, 10 to the units 37, 38. The unit applies air brake pressure to brake cylinders 3 and 4.
Useful for replacing hydraulic brake pressure to reach .

The operation of antiskid devices is well known.

The configuration of the pressure control valve unit 22 includes three multi-directional main control valves 17, 18, 1 provided as main valves.
9 is assigned an identical control magnet with a plunger with a closing member as the pre-control directional control solenoid valve 11, 12, 13, and the multi-directional control valve 1
7, 18, 19 diaphragm valve members 26, 2
7 and 28 are similarly uniform on the pressure side. At the connection points where current does not flow, the work chamber connection is interrupted by the plunger of the precontrol directional control valves 11, 12, 13. The valve unit 22 is configured as a two-pass configuration.

This two-pass configuration is based on the front control cylinders 39, 3.
directly controlling the pressure of the compressed air at 9' and thus indirectly but precisely controlling the pressure of the compressed air at the master cylinder 4.
0,40' to the wheel brake cylinders 3,4
control the hydraulic pressure in the In this way, a precisely uniform control operation is achieved, as in the case of pure compressed air brakes. Throttles or other adaptations required in the case of hydraulic control can be omitted here.

When the brake pressure controlled by the brake valve 2 is eliminated, the pressure also decreases in the pre-control cylinders 39, 39' and thus in the master cylinder 4.
Due to the direct connection to 0,40', the pressure is also reduced in the wheel brake cylinders 3,4. In this case, when the pre-control directional control solenoid valves 11, 12, 13 are energized, the branch conduit 1 to the valve inlet 32 is first
4, 16, the pressure in the working chambers 29, 31 is reduced. In this case, valve seats 23, 24, 25
is opened and a pressure reduction takes place in the precontrol cylinders 39, 39'.

FIG. 2 shows a schematic representation of a motor vehicle with two axles 41, 42 with hydraulically braked wheels. A two-way pressure control valve unit 43, 44 is used for each axle and a unit 45, 46 or 47, 48 for each wheel monitored by a sensor.
Pressure control valve units 43, 44 and unit 45
48 corresponds to FIG. A two-circuit compressed air brake valve 49 is used as a brake valve.

FIG. 3 is a schematic diagram of a motor vehicle with a two-circuit brake system. The two-circuit brake valve 66 controls compressed air for two two-pass pressure control valve units 67, 68.
Reference numeral 68 has the same structure as the pressure control valve unit 22 of the above embodiment. Two units 69, 70 or 71, 72, consisting of two front control cylinders and a master brake cylinder, are arranged downstream of each pressure control valve unit 67 or 68, via which the front axle 73 and the rear axle are connected. Hydraulic wheel brake cylinders (not shown) on shaft 74 are supplied with hydraulic pressure medium.

The two pressure control valve units 67, 68 are flanged together and thus form one component. However, it is also possible, for example, to combine them into only one housing. The casing is
It has a central bayonet bushing 75 for the necessary conduit connections to the pre-control directional solenoid valve.

In this way the wiring is simplified and the invention is particularly easy to test.

[Brief explanation of the drawing]

FIG. 1 shows a cut-away circuit diagram of an antiskid device with a two-channel pressure control valve unit; FIG. 2 shows a two-channel pressure control valve unit, one each for hydraulically braked wheels and one for compressed air; FIG. 3 is a circuit diagram of a two-circuit brake showing the combination of a two-path pressure control valve unit. 1... Compressed air storage container, 2... Brake valve, 3,
4... Brake cylinder, 5, 6... Wheel, 7...
...Axle, 8,9,10...Brake conduit, 11,
12, 13... Front control direction control solenoid valve, 14, 1
5, 16... Branch conduit, 17, 18, 19... Main directional control valve, 20, 21... Branch conduit, 22...
Pressure control valve unit, 23, 24, 24', 25
... Valve seat, 26, 27, 28 ... Diaphragm member, 29, 30, 31 ... Working chamber, 32 ... Valve inlet, 33 ... Rod, 34 ... Closing member, 35 ... Valve seat, 36 ... ...Outside air connection, 37, 38...Unit, 39,39'...Front control cylinder, 40,4
0'...Master cylinder, 66...Brake valve, 6
7, 68...pressure control valve unit, 69, 70,
71, 72...Unit, 73...Front axle, 74...
...Rear shaft, 75...Push-in bushing.

Claims (1)

[Claims for Utility Model Registration] 1. An anti-skid device for both wheel brakes provided on one wheel of a motor vehicle, comprising one 3-port 2-position main directional control valve 18 connected to a brake conduit. The outlet of the 3-port 2-position main directional control valve is 1, respectively.
two branch conduits 20, 21 each lead to one brake cylinder 3, 4, so that the three-port two-position main directional control valve commonly controls both brake cylinders; Furthermore, at least one front control valve 12 is provided for switching the operating force of the three-port two-position main directional control valve, and the front control valve is controlled when the wheels tend to lock.
The position of the main directional control valve 18 is adapted to bring the pressure reduction position to the one branch conduit 20.
, front control 3-port 2-position directional control solenoid valve 11
One unique 2-port 2-position main directional control valve 17 is provided, operated by a pre-controlled 3-port 2-position directional solenoid valve 13, and in the other branch conduit 21, operated by a pre-controlled 3-port 2-position directional control solenoid valve 13. One unique 2-port 2-position main directional control valve 19 is provided which, in the event of a skid, switches the 3-port 2-position main directional control valve 18 to the pressure reducing position by means of the pre-control valve 12. two twos
Among the port 2 position main directional control valves 17 and 19,
2-port 2-position main directional control valve 17 assigned to one of the wheels 5 or 6 that does not have a tendency to lock.
or 19 is closed to maintain the pressure in the brake cylinder 3 or 4 assigned to this one wheel, and in this state, the brake cylinder 4 or 3 assigned to the other wheel 6 or 5 is anti-lock controlled. The 3 port 2 position main directional control valve 18 and both 2
In a type in which the port 2-position main directional control valves 17 and 19 cooperate to control the pressure inside each brake cylinder 3 and 4, the 3-port 2-position main directional control valve 18 and The two-port two-position main directional control valves 17, 19 are designed as pressure control valve units 22, 43, 44, 67, 68 for hydraulically operating the brakes of at least two motor vehicle wheels. Between the pressure control valve unit and the brake cylinders 3, 4 are units 37, 38, 45, 46, 4 consisting of a front control cylinder and a master cylinder.
7, 48, 69, 70, 71, and 72. 2. The anti-skid device according to claim 1, wherein the pressure control valve units 67, 68 of the two automobile axles 73, 74 are combined into one unit. 3. Anti-skid device according to claim 2, in which the pressure control valve units 67, 68 are provided with a central electrical push-fit bushing 75. 4 In the case of hydraulic wheel brakes, pressure control valve units 22, 43, 4 are used instead of check valves.
4, 67, 68 can be used for the anti-skid device according to claim 3.