JPS606818B2 - Anti skid brake device for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an anti-skid brake device for automobiles, particularly a brake oil chamber that generates a braking force in a braking device when it receives a brake hydraulic pressure generated in response to a braking operation in a brake hydraulic pressure generating source. ; upon receiving the control hydraulic pressure generated in a control hydraulic pressure generation source in a system different from the braking hydraulic pressure generation source, the braking device;
a control oil chamber that generates a counterbraking force that opposes the braking force; an anti-skid hydraulic control device that introduces and controls the control oil pressure from the control oil pressure generation source to the control oil chamber;
The anti-skid hydraulic control device is provided with a normally closed valve that is connected between the control oil chamber and the control oil pressure generation source and becomes a barrier state when the braking force is too large. A second oil passage system is provided with a normally open valve that is closed when the braking force is too large. The present invention relates to a type of device having an oil passage system.

In this type of anti-skid brake device for car bran,
When the anti-skid hydraulic control device is accidentally activated due to traveling vibration, impact, or other causes in a non-braking state and the normally closed valve of the first oil passage system is temporarily opened, control hydraulic pressure is introduced into the control oil chamber. For example, if the braking device is a disc brake device with a built-in hydraulic cylinder, the piston may temporarily generate a counterbraking force in the braking device due to the counterbraking force. By retreating from the position, the gap between the friction pad and the brake disc, and therefore the invalid stroke of the piston, becomes larger than necessary, and during critical braking, the braking device cannot quickly and reliably perform its original braking function. There is a risk that it will disappear.

The present invention has been proposed in view of the above, and even if the anti-skid hydraulic control device malfunctions in a non-braking state where the brake hydraulic pressure is below the set pressure, the control hydraulic pressure from the control hydraulic pressure generation source is transmitted to the control oil chamber. The object of the present invention is to provide an anti-skid brake device for wheels that eliminates the fear of the conventional one by preventing the above-mentioned type of anti-skid brake device from
The first oil passage system is provided with a brake hydraulic pressure responsive valve in series with the normally closed valve, which closes when the brake hydraulic pressure is below a set pressure and opens when it exceeds the set pressure. .

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, in FIG. Braking oil is sent to the braking devices 4, 4' provided for each wheel via the respective wheels.

The structure of each brake device 4, 4' is exactly the same, so to explain the brake device 4 in detail, a wheel cylinder 6 is formed in the casing 5, and the wheel cylinder 6 is in sliding contact in the axial direction. The rod 8 of the piston 7 extends outwardly through the end wall 9 of the wheel cylinder 6 in a weldable manner. The brake pad 10 attached to the outer end of the rod 8 and the brake pad 11 attached to the casing 5 side press the brake disc 12, which rotates integrally with the wheel, from both the front and back sides. There is. In addition, in the wheel cylinder 6, an oil passage 3 is provided on the opposite side of the end wall 9 of the piston 7 via a boat 13.
A brake oil chamber 14 suitable for this purpose is formed, and a control oil chamber 16 is formed on the end wall 9 side of the piston 7 and is connected to the anti-skid hydraulic control device A via a boat 15.
is formed. Similarly to the braking device 4, the braking device 4' also has a pair of brake pads 10', 1 1
' is adapted to pinch the brake disc 12', and a boat 13 is provided in the wheel cylinder 6'.
A brake oil chamber 14', which is connected to the oil line 3 through the casing 15', and a control oil chamber 16', which is connected to the anti-skid hydraulic control system A through the boat 15', are formed.

The anti-skid hydraulic control device A is connected to the first hydraulic system B and the second hydraulic system B.
In the first oil path system B, the control oil sucked from inside the oil tank T through the oil path 17 by a control oil pressure generating source P such as a pump and pressurized is , oil road 18,
After passing through a check valve 19, a pressure accumulator 20, and a brake hydraulic pressure response valve 21, the hydraulic pressure is sent to the brake device 4 through a normally closed valve 22, a boat 15, and into a control oil chamber 16. The oil is sent to the device 4' via a normally closed valve 22' and a boat 15' to a control oil chamber 16'.

In addition, in the second oil passage system C, each control oil chamber 16, 1
The control oil in 6' is returned to oil tank T via boats 15, 15' and normally open valves 23, 23', respectively. Each normally closed valve 22, 22' and each normally closed valve 23
, 23' are controlled to open and close by a logic control circuit 25 that performs logical operations and generates control output signals based on input information sent from a detector 24 that detects necessary basic data such as wheel speed. , among these, each normally closed valve 22, 22' is normally in a closed state, but when the braking force of the corresponding braking device 4, 4' is too large, it is controlled to be in an open state. The normally open valves 23, 23' are normally in an open state, but are controlled to be in an open state when the braking force of the corresponding braking device 4, 4' is too large.

The brake hydraulic pressure responsive valve 21 receives the action of the brake hydraulic pressure via the oil passage 26 that communicates with the oil passage 3, and is normally in a closed state, but when the brake hydraulic pressure exceeds a set pressure, it responds to the brake hydraulic pressure. It is designed to be in an open state.

Further, between the check valve 19 and the control oil pressure generation source P, an oil passage 27 having a relief valve 28 in the middle branches from the oil passage 18, and the control oil pressure in the oil passage 18 exceeds the set pressure. Sometimes, excess control oil in the oil passage 18 is returned to the oil tank T via the relief valve 28. FIG. 2 shows an example of a detailed structure of the brake hydraulic pressure responsive valve 21. Inside the casing 29, there is a cylinder chamber 31 whose outer end is closed off by an end wall 301, a valve chamber 33 whose outer end is closed off by an end wall 32, and a cylinder chamber 31 that passes through the cylinder chamber 31 and the valve chamber 33 in the box direction. A through hole 34 is formed. The rod 37 of the piston 35, which is constantly pressed toward the end wall 30 by a pressing spring 36 which is slidably fitted with iron in the cylinder chamber 31, is fitted with iron into the through hole 34 so that it can slide freely. The tip flanges reach the vicinity of the valve seat of the valve chamber 33. The valve ball 38 inserted into the valve chamber 33 is always pressed against the valve formed between the valve chamber 33 and the through hole 34 by a pressing spring 39 interposed between the valve ball 38 and the end wall 32. The valve ball 38 is pressed toward the seat side, and normally the piston 35 is in contact with the end wall 301, so the valve ball 38 is pressed against the rod 3.
The valve seat 7 is seated on the valve seat without being pressed by the valve chamber 33 and the through hole 34, thereby blocking the valve chamber 33 and the through hole 34. piston 35
The cylinder chamber 31 between the end wall 30 and the end wall 30 communicates with the oil passage 3 via the boat 40, and the annular chamber formed between the small diameter portion of the tip of the rod 37 and the through hole 34 communicates with the oil passage 3 through the boat 40. 41 to each normally closed valve 22, 22', and the valve chamber 33 is connected to the pressure accumulator 20 via a boat 42. Therefore, when the braking oil pressure in the oil passage 3 is lower than the set pressure, the piston 35 is pressed by the pressing force 36 and is rolling against the end wall 30', so that the valve ball 38 is not pressed by the rod 37. The pressure accumulator 2
0 and each normally closed valve 22, 22' is cut off.

When the braking oil pressure in the oil passage 3 exceeds the set pressure, the piston 35
moves toward the valve chamber 33 against the pressing force of the pressing spring 36', and along with this, the rod 37 pushes the valve ball 38 against the pressing spring 39.
The valve chamber 33 and the through hole 34 are moved by pressing against the pressing force of the valve chamber 33 and the through hole 34. As a result, the pressure accumulator 20 and each normally closed valve 22, 22
’ will be communicated. With the above structure, when the brake pedal is not depressed, the master cylinder 2 does not generate braking oil pressure, and the braking oil pressure in the oil passage 3 is below the set pressure, so the braking pressure responsive valve is activated. 21 is in a closed state, cutting off between the pressure accumulator 20 and each normally closed valve 22, 22'.

Therefore, at this time, even if for some reason the normally closed valve 2
Even if the normally closed valve 22 or the normally closed valve 22' malfunctions and becomes open, the control oil sent from the control oil pressure generation source P will not flow into the control oil chamber 16 or the control oil chamber 16'. Therefore, even if the pads 10, 11 have a large amount of wear, the gaps between the pads 10, 10': 11, 11' and the brake discs 12, 12', and therefore the invalid stroke of the pistons, do not change, and each braking device 4, 4' is maintained in a state where it can quickly generate braking force at any time. When the brake pedal 1 is depressed, a brake oil pressure generation source 2 generates a brake oil pressure, and the brake oil sent therefrom flows into each brake oil chamber 14, 14' through an oil path 3.

As a result, each braking device 4, 4' generates a braking force on a wheel integral with the corresponding brake disc 12, 12'. At this time, when the brake oil pressure in the oil passage 3 exceeds the set pressure, the brake pressure applying valve 21 becomes open, and the pressure accumulator 2
The control oil that has passed through zero reaches each normally closed valve 22, 22', but as long as the braking force of each braking device 4, 4' is appropriate, each normally closed valve 22, 22' remains closed. Therefore, the control oil does not flow into each control oil chamber 16, 16'. During this time, each control oil chamber 16, 16' is opened into the oil tank T via a normally open valve 23, 23', respectively. If the pressing force on the brake pedal is too large and the braking force of the braking device 4 or the braking device 4' is too large, the corresponding normally closed valve 22 or 22' opens, and the corresponding normally open valve 23 or 23 opens. ' is closed, and as a result, control oil flows into the control oil chamber 16 or 16', so that the corresponding brake device 4 or 4 is closed.
The braking force of ' is suppressed, and the corresponding wheel is prevented from becoming locked.

In addition, by disposing the pressure accumulator 20 between the brake pressure responsive valve 21 and the control oil pressure generation source P, the oil passage that is generated due to the opening and closing operations of the brake pressure responsive valve 21 and the normally closed valves 22, 22' is reduced. Since the hydraulic shock in the pressure accumulator 18 is buffered and absorbed by the pressure accumulator 2, the oil passage system is prevented from being damaged by the hydraulic shock.

As described above, according to the present invention, when the brake oil pressure generated in the brake oil pressure generation source 2 is received in response to a braking operation, the brake oil chambers 14, 14 generate a braking force in the brake devices 4, 4'.
' and: control for generating a counterbraking force in the braking devices 4, 4' to oppose the braking force when receiving the control hydraulic pressure generated in a control hydraulic pressure generating source P that is separate from the braking hydraulic pressure generating source 2. Oil chambers 16, 16' and their control oil chambers 16, 16
an anti-skid hydraulic control device A for introducing and controlling the control hydraulic pressure from the control hydraulic pressure generating source P into the control oil chambers 16, 16'; A first oil passage system B that is connected to the generation source P and has normally closed valves 22 and 22' interposed therebetween, which enters the valve state when the braking force is too large;
A second oil is conveyed between the control oil chambers 16, 16' and the oil tank T and has normally open valves 23, 23' interposed therebetween, which are closed when the braking force is too large. In the anti-skid brake system for wheels, the first oil passage system B has a valve that closes when the braking oil pressure is below a set pressure and opens when it exceeds the set pressure. Braking hydraulic pressure response valve 2
1 is provided in series with the normally closed valve 22, so in a non-braking state where the brake oil pressure is below the set pressure, the brake oil pressure responsive valve 21
Therefore, in this state, even if the anti-skid hydraulic control device A malfunctions due to traveling vibrations, the control hydraulic pressure generation source P can be maintained in a disconnected state. There is no longer any fear that the control oil pressure from L will act on the control oil chambers 16, 16r and generate a reaction braking force in the brake devices 4, 4', and as a result, the L brake devices 4, 4' will be in the normal non-braking state. Since this is maintained, the original brake engine can be used normally and quickly during braking.

Moreover, during braking when the braking oil pressure exceeds the set pressure, the braking oil pressure response valve 21 is automatically switched to the valve state, so that when the normally closed valves 22, 22' are opened, the first oil passage system B The control oil pressure introduced into the control oil chambers 16, 16' through the control oil pressure chambers 16, 16' generates a reaction braking force in the brake devices 4, 4', and the original anti-skid effect is achieved without any problem.

[Brief explanation of the drawing]

Fig. 1 is an enlarged conceptual diagram of a main part showing an example of the case where the anti-skid brake device for wheels of the present invention is applied to two braking devices, and Fig. 2 is a vertical sectional view showing an example of a brake hydraulic pressure responsive valve. be. 2... Braking oil pressure generation source, 4, 4'... Braking device, 14, 14'... Braking oil chamber, 16, 16'...
...Control oil chamber, 20...Pressure accumulator, 21...
・Braking hydraulic pressure responsive valve, 22, 22'... Normally closed valve, 23
, 23'... Normally open valve, A... Anti-skid hydraulic control device, B... First oil line system, C...
Second oil passage system, P... Control hydraulic pressure generation source, T...
Oil tank. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1 Braking oil chambers 14, 14' which generate braking force in the braking devices 4, 4' when receiving the braking oil pressure generated in response to a braking operation in the braking oil pressure generating source 2; Control oil chambers 16, 16' which, when receiving braking oil pressure generated in a control oil pressure generation source P that is separate from the generation source 2, generate a counter-braking force in the braking devices 4, 4' to oppose the braking force.
and; the control oil pressure generation source P to the control oil chambers 16, 16'.
and an anti-skid hydraulic pressure control device A for introducing and controlling the control hydraulic pressure from the control hydraulic pressure source P, and the anti-skid hydraulic control device A is provided in the middle of communication between the control oil chambers 16, 16' and the control hydraulic pressure generating source P. includes a first oil passage system B in which normally closed valves 22, 22' that open when the braking force is too large are installed; and the control oil chambers 16, 16.
A second oil passage system C is provided which communicates between ' and the oil tank T and has normally open valves 23, 23' interposed therebetween, which are closed when the braking force is too large. In the anti-skid brake system for a vehicle, the first hydraulic system B includes a brake hydraulic pressure responsive valve 21 that closes when the brake hydraulic pressure is below a set pressure and opens when the brake hydraulic pressure exceeds the set pressure. An anti-skid brake device for a vehicle, characterized in that it is provided in series with a normally closed valve 22. 2. In the anti-skid brake system for a vehicle according to claim 1, the first oil passage system B is located in the middle of an oil passage that communicates the brake oil pressure response valve 21 with the control oil pressure generation source P. An anti-skid brake device for a vehicle, which is equipped with a pressure accumulator 20.