JPS6056661B2 - Hydraulic power brake system - Google Patents

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to a hydraulic power brake system for a vehicle such as an automobile, and particularly to a first wheel cylinder, and a pressure control system for the first wheel cylinder. a driver-operated first control valve that controls the supply and discharge of liquid; a second wheel cylinder; a driver-operated second control valve that controls the supply and discharge of pressurized liquid to the second wheel cylinder;
and a hydraulic power brake system including first and second accumulators for storing the pressure fluid.

(Prior Art) A conventional device of this type is one described in Japanese Patent Application Laid-Open No. 156-1983.

In this conventional device, the pressurized liquid in the first accumulator is sent only to the first wheel cylinder via the first control valve, and the pressurized liquid in the second accumulator is sent only to the second wheel cylinder via the second control valve. Therefore, even if the pressure fluid in one of the first and second accumulators, for example, the first accumulator, is depleted, the pressure fluid in the second accumulator is supplied to the second accumulator through the second control valve. Brake use is obtained by supplying the brake fluid to two wheel cylinders and activating the second wheel cylinder. (Problem to be Solved by the Invention) By the way, there is no abnormality in the circuit section from the first (or second) control valve to the first (or second) wheel cylinder, but there is a problem in the first (or second) accumulator. If the pressure fluid in the first (or second) accumulator is lost due to damage to the circuit portion that supplies pressure fluid to the first (or second) control valve, ) The pressure liquid in the accumulator is transferred to the first (
Or 2nd) By supplying it to the control valve as well, pressure fluid can be supplied to the first and second wheel cylinders during braking to obtain a braking action by the operation of the first and second wheel cylinders. However, in the conventional device described above, the pressure fluid in the second (or first) accumulator can only be supplied to the second (or first) wheel cylinder, so the braking action is only due to the operation of the second (or first) wheel cylinder. I can't get it.

Therefore, the present invention has been designed to reduce the pressure fluid in the first (or second) accumulator to the first (or second), although there is no abnormality in the circuit section from the first (or second) control valve to the first (or second) wheel cylinder. or 2) If the pressure fluid in the first (or second) accumulator is lost due to damage to the circuit supplying the control valve, the pressure fluid in the second (or first) accumulator is 1st (
or 2) the technology that the control valve is also supplied so that during braking, pressurized fluid is supplied to the first and second wheel cylinders so that a braking action is obtained by the operation of the first and second wheel cylinders; This will be a major issue. [Structure of the Invention] (Means for Solving the Problems) The technical means taken by the present invention to solve the above technical problems are as follows:
It has an inlet and a second inlet for receiving pressurized liquid from the second accumulator, and first and second outlets for sending out the pressurized liquid received from the first or second inlet, and has an inflow from either one of the two populations. Prevents pressure fluid from flowing out from the other side. In addition, a safety valve is provided which stops the distribution of pressure liquid to the one outlet when an abnormally large flow rate occurs at either one of the two outlets.

(Function) By providing the above safety valve, if there is no abnormality in the circuit from the safety valve to the first and second wheel cylinders via the first and second control valves, the first (or second) Even if there is a shortage of pressure fluid in the accumulator, the pressure fluid in the second (or first) accumulator is supplied to the first and second control valves via the safety valve. Pressure fluid is supplied to the wheel cylinders, and a braking action is obtained by operating the first and second wheel cylinders.

(Example) Hereinafter, the present invention will be made more clear by describing an example of the present invention based on the drawings.

In FIG. 1, a reservoir 1 has first and second liquid chambers 3 and 4 separated by a partition wall 2. As shown in FIG. The height of the partition wall 2 is slightly lower than the standard liquid level height of each liquid chamber 3, 4, and liquid exchange between the liquid chambers 3, 4 is normally possible. The main pump 6 (P1) is connected to the first liquid chamber 3 via the suction vibrator 5.
The liquid inside is sucked and discharged to the charging valve 7. The outlet of this charging valve 7 is connected to the check valve 21 and the vibe 1.
4 to the first accumulator 12 and the first inlet of the safety valve 13 shown in FIGS.
03a), and its return port communicates with the first liquid chamber 3 via the vibrator 8. Auxiliary pump 6″ (P2)
suctions the liquid in the second liquid chamber 4 through the suction vibrator 5 and discharges it to the charging valve 7''. 2 accumulator 12″ and safety valve 1
3 (203b in FIG. 2). A well-known unloading valve is used as the charging valve 7, 7'', but a relief valve can be used as the charging valve 7.The safety valve 13 is connected to the first outlet (204 in FIG. 2). and second
An outlet (2040 in FIG. 2), the first outlet of which is connected to the inlet of the first control valve 16 by the vibrator 15, and the second outlet thereof to the inlet of the second control valve 16'' by the vibrator 15''. A charging valve 7 is installed at the pilot pressure outlet of the safety valve 13.
, 7'' common pilot pressure vibrator 20 is connected.
The first and second control valves 16, 16'' are well-known valves operated by the driver, and the outlet of the first control valve 16 is connected to the first wheel cylinder 18 via a vibrator 17, and the outlet of the second control valve 16'' is connected to the first wheel cylinder 18 through a vibrator 17. are respectively connected to the second wheel cylinder 1'' via a vibrator 17'', and further connected to a first control valve 16''.
The return port of the second control valve 1' communicates with the second liquid chamber 4 via the vibrator 19, and the return port of the second control valve 1'' communicates with the second liquid chamber 4 via the vibrator 19'', 19, respectively. They may be configured in an arrangement relationship or may be configured in a parallel arrangement relationship.

Next, details of the safety valve 13 will be explained with reference to FIGS. 2 and 3.

The main body 201 has a cylinder 202 with one end open,
The end wall of this cylinder 202 has a first outlet 204 connected to the inlet of the first control valve 16 by means of a vibrator 15.
However, the plug 208 that closes the opening of the cylinder 202 is provided with a second outlet 204'' connected to the inlet of the second control valve 16'' by a vibrator 15''. Plug 2 having a first inlet 203a connected to 12
18 and a plug 21'' having a second inlet 203b connected to the second accumulator 12'' by the vibrator 14'' are screwed together. Check valves 217, 21r are incorporated in the spaces formed between the plugs 218, 21' and the main body 201. Inside the cylinder 202 are two pistons 205,
A central chamber 209 is defined on the opposite side of both pistons 205, 205'', and side chambers 210, 21'' are defined on the opposite side of the central chamber. A snap ring 206 is attached to the central circumferential wall of the cylinder 202 to define a sliding stop position of the pistons 205, 205'' in the relative approach direction, and the central chamber 209 has a pressurized liquid supplied to the inlets 203a, 203b. The check valves 217, 217'' are pushed open to allow water to flow through the passages 203, 203'' of the main body 201.
The pressure liquid that has flowed into the central chamber 209 is caused by the pistons 205, 205.
It is designed to flow into the side chambers 210, 21'' through orifices 211, 21'' provided in the side chambers 210, 21, respectively.
205'' toward the central chamber 209 side
7,207'' are arranged respectively.The side chamber 210 is provided with a valve seat 216 provided on the end surface of the cylinder 202.
The valve 212 corresponding to the valve seat 216 is slidably attached to the guide plate 215 by an E-ring 213 and a spring 214, and the guide plate 215 It is pressed against the piston 205 by a spring 207. The other side chamber 21' communicates with the second outlet 20C through the central hole of the valve seat 216' provided in the plug 208, and the valve 212' corresponding to the valve seat 216' has an E-ring 213' on the guide plate 215'. The guide plate 215'' is slidably attached to the piston 20 by a spring 207''.
5". The orifice 211 is connected to the first outlet 2
Only when the flow rate of 04 increases abnormally, a hydraulic pressure difference is generated between the central chamber 209 and the side chamber 210 that can displace the piston 205 against the spring 207 as shown in the third figure. 3. As shown in Figure 3, the area of the circle with the seal diameter A'' in contact with the valve seat 216 is set so that the state shown in Figure 3 is maintained by applying hydraulic pressure from the accumulators 12, 12'' to this area. ing.

The central chamber 209 communicates with a pilot pressure outlet (not shown) of the main body 201.

When comparing the on-load pressure and unload pressure of the charging valve 7 with the on-load pressure and unload pressure of the charging valve 7'', the charging valve 7 is slightly higher.

Here, the on-load pressure refers to the charging valve 7 or 7'' that pumps the discharged fluid from the pump 6 or 6'' to the accumulator 1.
2 or 12'', and the unload pressure is the pressure at which the charging valve 7 or 7'' sends the fluid discharged from the pump 6 or 6'' from the vibrator 8 or 8'' to the reservoir 1. This refers to the pressure at which unloading is activated when the pressure is returned to . When all parts of the system are normal and the hydraulic pressure in the accumulators 12, 12'' is zero, such as during the first operation after the system is completed, both the charging valves 7, 7'' operate on-load, and the main The discharge pressure liquid of the pump 6 is sent to the first accumulator 12, and the discharge pressure liquid of the auxiliary pump 6'' is sent to the second accumulator 12''.
The hydraulic pressure within 2,12'' increases.

When the fluid pressure in the accumulators 12, 12'' increases and reaches the unloading pressure of the charging valve r, the charging valve 7'' operates to unload and transfer the discharged liquid from the auxiliary pump 6'' to the second reservoir 1. Return it to the liquid chamber 4 and turn it on to the auxiliary pump 6.
'' becomes a no-load state.Then, the first accumulator 1
When the fluid pressure in the main pump 2 rises to the unloading pressure of the charging valve 7, the charging valve 7 operates to unload and return the fluid discharged from the main pump 6 to the first fluid chamber 3 of the reservoir 1, and the main pump 6 is in a no-load state. When the control valves 16, 16'' are operated to brake the vehicle, pressurized fluid flows from the first accumulator 12 with high fluid pressure through the vibrator 14 to the first inlet 2 of the safety valve 13.
03a, then push open the check valve 217 and open the passage 20.
3 into the central chamber 209. And central room 2
09, passes sequentially through the orifice 211, the side chamber 210, and the center hole of the valve seat 216, reaches the first outlet 204, and is simultaneously supplied to the first wheel cylinder 18 via the vibrator 15, the first control valve 16, and the vibrator 17. From the central chamber 209, the second outlet 20 passes sequentially through the orifice 21'', the side chamber 21'', and the central hole of the valve seat 216''.
4″, vibrator 15″, second control valve 16
'' and the second wheel cylinder 1'' via the vibrator 17''.
Braking action is performed by operating the wheel cylinders 18, 1'. Control valve 16,1
6" is released, wheel cylinder 18,
1'' returns to the second liquid chamber 4 of the reservoir 1 via the vibrator 17, 17' control valve 16, 1'' and the vibrator 19, 19''. Control valve 6, 162
When the pressure fluid in the first accumulator 12 is consumed by repeating the operation and its release, and the pressure of one fluid in the first accumulator 12 decreases to the same pressure as the fluid pressure in the second accumulator 12'', the pressure in the second accumulator 12 is reduced. Pressure fluid within 12'' also flows into the safety valve 13.

When the hydraulic pressure from the accumulators 12, 12'' drops to the on-load pressure of the charging valve 7, the charging valve 7 operates on-load, and the discharge pressure liquid of the main pump 6 is sent to the first accumulator 12. The hydraulic pressure in the first accumulator 12 is increased.On the other hand, the liquid discharged from the auxiliary pump 6'' is not sent to the second accumulator 12'', and the auxiliary pump 6'' is kept in an unloaded state.
If the circuit from the main pump 6 to the safety valve 13 is damaged and the pressure fluid in the first accumulator 12 is lost, when the control valves 16, 16'' are operated, the second
Pressure fluid in the accumulator 12'' is supplied to the wheel cylinders 18, 1'' via the vibrator 14'', the safety valve 13, the vibrators 15, 15', the control valves 16, 16'', and the vibrators 17, 17'', and
, 1', a braking action is performed.

As the pressure fluid in the second accumulator 12'' is consumed in this way, the fluid pressure in the second accumulator 12'' decreases and reaches the on-load pressure of the charging valve 7'', which causes the charging valve 7'' to turn on. Due to the load operation, the discharge pressure liquid of the auxiliary pump 6'' is sent to the second accumulator 12'' and accumulated therein. If the circuit section from the auxiliary pump 6'' to the safety valve 13 is damaged and the pressure fluid in the second accumulator 12'' is lost, the control valve 1
6,16'', the pressure fluid in the first accumulator 12 is released into the safety valve 13 of the vibrator 1, and the vibrator 15,1.
5″, control valve 16, 165, vibe 17,
17" to the wheel cylinder 18,1",
A braking action is performed by operating the wheel cylinders 18, 1'.

As the pressure fluid in the first accumulator 12 is consumed in this way, the fluid pressure in the first accumulator 12 decreases to the on-load pressure of the charging valve 7, and the on-load operation of the charging valve 7 causes the main The discharge pressure liquid of the pump 6 is sent to the first accumulator 12 and accumulated therein. If an abnormally large flow rate occurs at the first outlet 204 due to damage to the circuit section from the vibrator 15 to the first wheel cylinder 18, the hydraulic pressure in the side chamber 210 is reduced to the hydraulic pressure in the central chamber 209 due to the presence of the orifice 211. (equal to the hydraulic pressure from the accumulators 12, 12''), and this hydraulic pressure difference between the central chamber 209 and the side chamber 210 causes the piston 205 to move toward the first outlet 204 against the spring 207. The valve 212 slides against the valve seat 216 to close the first outlet 204 as shown in the third figure.

After the valve 212 contacts the valve seat 216, the side chamber 2
10 becomes equal to the hydraulic pressure in the central chamber 209 and the valve 212 remains in contact with the valve seat 216. As a result, the pressure fluid in the accumulators 12, 12'' can be supplied to the second wheel cylinder 18'' by operating the second control valve 16'' to obtain a braking action. If an abnormally large flow rate occurs at the second outlet 204'' due to damage to the circuit portion leading to the second outlet 204'', the safety valve 13 will stop the distribution of pressure fluid to the second outlet 204''. 12'' can be supplied to the first wheel cylinder 18 by operating the first control valve 16 to obtain a braking effect.

In this case, the operation of the safety valve 13 is as follows:
Since it is believed that the operation can be easily understood from the explanation of the operation when an abnormally large flow rate occurs at the first outlet 204 due to damage to the circuit section extending from the first outlet 204 to the first wheel cylinder 18, the explanation will be omitted. [Effects of the Invention] As explained above, the present invention includes a first wheel cylinder, a first control valve operated by the driver for controlling supply and discharge of pressure fluid to and from the first wheel cylinder, and a second
A hydraulic power brake comprising a wheel cylinder, a second control valve operated by the driver for controlling the supply and discharge of pressurized fluid to and from the second wheel cylinder, and first and second accumulators for storing the pressurized fluid. The system includes a first inlet for receiving pressurized liquid from the first accumulator, a second inlet for receiving pressurized liquid from the second accumulator, and first and second outlets for discharging the pressurized liquid received from the first or second inlet. and prevents the pressure fluid flowing in from either one of the two outlets from flowing out from the other, and when an abnormally large flow rate occurs at either one of the two outlets, A safety valve is installed to stop the distribution of pressure fluid to the outlet.If there is no abnormality in the circuit from the safety valve to the first and second wheel cylinders via the first and second control valves, the first ( or 2nd) Even if the pressure fluid in the accumulator is lost, the 2nd (or 1st)
Pressure fluid in the accumulator is supplied to the first and second control valves via the safety valve, so during braking, the pressure fluid is supplied to the first and second wheel cylinders and the first and second wheel cylinders are operated. braking action is obtained, and the first (
or 2nd) If the circuit section leading to the 1st (or 2nd) wheel cylinder via the control valve is damaged, the pressure fluid in the 1st and 2nd accumulators will flow from the safety valve to the 2nd (or 1st) wheel cylinder. Since the pressure fluid is supplied to the second (or first) wheel cylinder via the control valve, the supply of pressure fluid from the pump to the first and second accumulators is stopped, and from the safety valve to the first (or second) wheel cylinder.
) In severe cases where the circuit section leading to the first (or second) wheel cylinder via the control valve is damaged, the second (or first) wheel cylinder is closed until the pressure fluid in the first and second accumulators is exhausted. It is possible to obtain a braking effect by the operation of the brake system, which has the effect of significantly improving vehicle brake safety compared to conventional devices.

[Brief explanation of drawings]

Fig. 1 is a system diagram of one embodiment of the present invention, and Fig. 2 is a system diagram of an embodiment of the present invention.
FIG. 3 is a sectional view of the safety valve showing the operating state of the safety valve. Explanation of symbols, 1... Reservoir, 3...
1st liquid chamber, 4...2nd liquid chamber, 6...main pump, 6''...auxiliary pump, 7,7''...charging valve, 12... ...first accumulator,
1゛2″...Second accumulator, 16...
...First control valve, 16''...Second control valve, 18...First wheel cylinder, 18''...Second wheel cylinder.

Claims (1)

[Claims] 1 A first wheel cylinder, a first control valve operated by the driver that controls the supply and discharge of pressurized fluid to this first wheel cylinder, a second wheel cylinder, and a second wheel cylinder that supplies and discharges pressurized fluid to and from this second wheel cylinder. a hydraulic power brake system comprising a second operator-operated control valve for controlling and first and second accumulators for storing said hydraulic fluid; a first inlet for receiving hydraulic fluid from said first accumulator; a second inlet for receiving pressurized fluid from a second accumulator;
Or, it has first and second outlets for sending out the pressurized liquid received from the second inlet, and prevents the pressurized liquid that has flowed in from either one of the two inlets from flowing out from the other, and both of the outlets A hydraulic power brake system equipped with a safety valve that stops the distribution of pressure fluid to one of the outlets when an abnormally large flow rate occurs at one of the outlets.