JPH042459B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a hydraulic supply device in which a high-pressure pump and a high-pressure accumulator are connected by a flexible high-pressure hose, and particularly relates to extending the life of the high-pressure hose. It is.

BACKGROUND ART The above-mentioned hydraulic pressure supply device is used when it is necessary to allow relative movement between the high-pressure accumulator and the high-pressure pump, and the hydraulic pressure supply device of the anti-lock type hydraulic brake system of an automobile is used for this purpose. This is an example. In this case, the high pressure accumulator
The fluid is stored at a high pressure of about 200Kg/ ^cm2 , and when it becomes necessary to control the fluid pressure of the brake wheel cylinder to prevent the wheels from locking, the fluid is supplied to the fluid pressure control device. be. In automobile hydraulic brake systems, a hydraulic booster is sometimes used as a booster that boosts the operating force applied to an operating member such as a brake pedal and transmits it to the master cylinder. A pressure supply device is used.

In such a liquid pressure supply device, high liquid pressure acts on the high pressure hose not only when the pump is operating but also when the pump is stopped, which inevitably shortens the life of the high pressure hose. . In view of this, the present applicants proposed a hydraulic supply device in Utility Application No. 15426/1987 in which high pressure is not applied to the high pressure hose while the pump is stopped. A check valve is provided between the high-pressure hose and the high-pressure accumulator to prevent liquid from flowing out from the high-pressure accumulator, and a hydraulic pressure is placed on the high-pressure pump side of the check valve to eliminate the liquid pressure in the high-pressure hose when the pump is stopped. A solution is provided.

Problems to be Solved by the Invention The present invention further develops the above-mentioned idea, and provides a special type of charging pump and charging pump for actively pushing liquid into the high-pressure pump to increase the efficiency of the high-pressure pump. This was done in order to achieve the purpose of eliminating the hydraulic pressure in a high-pressure hose at a low cost by using a charging accumulator in a hydraulic pressure supply device equipped with a mulrator.

Means for Solving the Problems The present invention provides (a) a high-pressure accumulator that stores liquid at high pressure and supplies it to the target device as needed; and (b) a part of which is formed by a flexible high-pressure hose. , (c) a high-pressure pump connected to the other end of the high-pressure liquid passage and supplying liquid to the high-pressure accumulator; (d) ) a piston-type charging accumulator connected to the high-pressure pump and supplying liquid stored at a lower pressure from the high-pressure accumulator to the high-pressure pump; and (e) a charging pump supplying liquid to the charging accumulator. In the liquid pressure supply device including, the charging accumulator is provided with a leak means for leaking the liquid stored in the charging accumulator little by little, and the high pressure liquid passage and the charging accumulator are communicated with each other by a communication passage, and the A second valve is provided in the communication passage to prevent the flow of liquid from the high-pressure liquid passage to the charging accumulator.
A check valve is provided, and when liquid is not stored in either the piston of the charging accumulator or the valve of the second check valve, the other of them is provided with a check valve. The gist is that a valve-opening protrusion is provided which opens the second check valve when brought into contact with the valve opening protrusion.

Function and Effect In the hydraulic pressure supply device configured as described above, the high pressure liquid passage and the charging accumulator are completely shut off by the second check valve while the high pressure pump and the charging pump are in operation. For,
The entire amount of liquid discharged from the high-pressure pump is supplied to the high-pressure accumulator. Naturally, when the high-pressure pump is stopped, the charging pump is also stopped, but after a certain period of time after the charging pump stops, liquid is not stored due to liquid leakage from the charging accumulator leakage means. Return to state. Accordingly, the piston of the charging accumulator returns to its original position, and the valve opening protrusion opens the second check valve to communicate the high pressure fluid passage with the charging accumulator. Therefore, the hydraulic pressure in the high-pressure passage is eliminated, and high pressure does not act on the high-pressure hose while the high-pressure pump is stopped, resulting in the effect of lengthening the life of the high-pressure hose.

Moreover, since the second check valve is opened mechanically when the piston of the charging accumulator returns to its original position, it does not require electrical control means, can achieve its purpose at low cost, and This results in a highly reliable high-pressure hose protection type hydraulic supply device with less fear of damage.

Embodiment Hereinafter, an embodiment in which the present invention is applied to a hydraulic pressure supply device for an anti-lock type hydraulic brake system for an automobile will be described based on the drawings.

FIG. 1 is a system diagram of an anti-lock type hydraulic brake system, in which numeral 10 represents a brake pedal and numeral 12 represents a master cylinder. The master cylinder 12 is 2
It is a tandem type with two mutually independent pressurizing chambers, and the hydraulic pressure generated in each pressurizing chamber is transmitted through liquid passages 14 and 16 to the front wheel cylinder of the front wheel brake and the rear wheel brake, respectively. Although the power is transmitted to the rear wheel cylinder, only the rear side system is representatively shown in the figure.

The liquid passage 16 has a proportioning valve 18
and a hydraulic pressure control device 20, which connects the master cylinder 12 and the rear wheel cylinder 22. The proportioning valve 18 reduces the hydraulic pressure in the master cylinder 12 at a constant rate, but since it is well known, a description thereof will be omitted. The hydraulic pressure control device 20 includes a hydraulic pressure control section 24 and a bypass section 25. The hydraulic pressure control section 24 includes a directional switching valve 26 and a hydraulic control piston 28,
The hydraulic pressure in the rear wheel cylinder 22 is controlled according to the hydraulic pressure in the hydraulic pressure chamber 30, and the bypass section 2
Reference numeral 5 includes a directional switching valve 32 and a bypass piston 34, which allows communication between the master cylinder 12 and the rear wheel cylinder 22 via a bypass passage 38 when hydraulic pressure ceases to act on the hydraulic pressure chamber 36.

The hydraulic pressure in the hydraulic chamber 30 of the hydraulic pressure control section 24 is controlled by a pressure increase/decrease switching solenoid valve 40 and a slow/slow control solenoid valve 42. The pressure increase/decrease switching solenoid valve 40 is
As the solenoid 43 is energized and demagnetized, the hydraulic pressure chamber 30
is communicated with the regulator 46 via the solenoid valve 42 for slow/sudden control and the liquid passage 44, and the liquid passage 4
8 to communicate with the reservoir 50, thereby increasing or decreasing the hydraulic pressure in the hydraulic pressure chamber 30. On the other hand, by changing the duty ratio of the pulsed excitation current supplied to the solenoid 52, the solenoid valve 42 for speed control can change the ratio of the time it is in the open state and the time it is in the closed state. It controls the pressure and the speed of depressurization. That is, both electromagnetic valves 40 and 42 are connected to the hydraulic pressure control device 20.
The hydraulic pressure in the rear wheel cylinder 22 is indirectly controlled via the hydraulic pressure in the rear wheel cylinder 22 to prevent the rear wheels from becoming locked. Excitation and demagnetization of the solenoids 43 and 52 are performed by a controller mainly composed of a microcomputer (not shown), but since this control is well known, detailed explanation will be omitted.

The regulator 46 includes a control piston 60 and a directional control valve 62.
The hydraulic pressure of the master cylinder 12 is introduced to the hydraulic pressure chamber 64 on one side of the cylinder through a liquid passage 66. The control piston 60 switches the directional control valve 62 between a state in which the hydraulic chamber 68 is communicated with the high-pressure accumulator 70, a state in which it is communicated with the reservoir 50, and a state in which it is not communicated with either, based on the increase or decrease in master cylinder pressure. , thereby reducing the hydraulic pressure of the high-pressure accumulator 70 to a hydraulic pressure higher than the master cylinder pressure by a predetermined value,
and the hydraulic pressure control device 20.

The high pressure accumulator 70 includes a check valve 72.
One end of the high-pressure liquid passage 74 is connected to the high-pressure liquid passage 74 via the high-pressure liquid passage 74 . The other end of the high-pressure liquid passage 74 is connected to a pump device 76, and a portion of this high-pressure liquid passage 74 is formed by a high-pressure rubber hose 78. The pump device 76 is adapted to be driven by a pump motor 80, and the pump motor 80 is driven by a hydraulic switch 8 provided in the high pressure accumulator 70.
The high pressure accumulator 70 is started and stopped based on the output signal No. 2, thereby maintaining the hydraulic pressure within the high pressure accumulator 70 within a predetermined range. 84 is a relief valve.

As is clear from the above description, in this embodiment, the high pressure accumulator 70, the high pressure liquid passage 7
4. Regulator 4 by pump device 76 etc.
A hydraulic pressure supply device that supplies hydraulic pressure to the electromagnetic valves 40, 42 and the hydraulic pressure control device 20 via the pump device 6 is configured, and the pump device 7, which is the main part thereof, is configured.
6, as shown in FIG. 2, a charging pump 92, a charging accumulator 94, and two high-pressure pumps 96 are incorporated into a common block 90, and the liquid is sucked through a suction port 98 and added to two stages. It is pressurized and discharged from the discharge port 100.

The charging pump 92 has a plunger 104 slidably and substantially liquid-tightly fitted into a housing 102, biased in one direction by a spring 105, and an eccentric drive shaft 106 connected to the pump motor. When rotated by the plunger 80, the plunger 104 is caused to reciprocate via the bearing 108. As the plunger 104 reciprocates, the volume of the pump chamber 110 increases and decreases, and liquid is sucked from the suction passage 112 through the suction valve 114 and discharged through the discharge valve 116 into the charging passage 118. The charging passage 118 is divided into two parts and connected to two high pressure pumps 96.
This charging passage 11 is connected to
8 is also connected to the charging accumulator 94.

The charging accumulator 94 has a piston 122 slidably and substantially liquid-tightly fitted into the housing 120 and is biased in one direction by a spring 124.
A pressure accumulation chamber 126 and a low pressure chamber 128 are formed on both sides of the pressure chamber 22. The pressure accumulation chamber 126 communicates with the charging passage 118, and the low pressure chamber 128 communicates with the suction passage 11.
2, and the piston 122 is formed with a relief passage 130 whose one end opens to the pressure accumulation chamber 126 and the other end opens to the outer circumferential surface of the piston 122. The opening of the relief passage 130 on the piston outer peripheral surface side is normally substantially closed by the housing 120, but if a certain amount of liquid is stored in the pressure accumulation chamber 126 and the piston 122 retreats a certain distance, the low pressure chamber 126 The liquid in the pressure accumulation chamber 126 is allowed to flow out to the low pressure chamber 128. The pressure accumulation chamber 126 is also in continuous communication with the low pressure chamber 128 via a relief passage 130 and an orifice 132, so that a small amount of liquid can flow into the low pressure chamber 128. The orifice 132 constitutes a leakage means,
It is also possible to use it as a leakage means by selecting an appropriate fitting clearance between the piston 122 and the housing 120.

The high-pressure pump 96 has a plunger 142 slidably and substantially liquid-tightly fitted into a housing 140, and is pressed against the eccentric drive shaft 106 by a spring 144 via a bearing 108. Therefore, the eccentric drive shaft 10
6 rotates, the plunger 142 reciprocates, the volume of the pump chamber 146 increases or decreases, liquid is sucked from the charging passage 118 through the suction valve 148, and the discharge valve 150 forms part of the high-pressure liquid passage 74. It is discharged into passage 152. At this time, since the charging accumulator 94 actively pushes the liquid into the high-pressure pump 96, the high-pressure pump 96 efficiently performs a pumping action.

The discharge passage 152 is communicated with the pressure accumulation chamber 126 of the charging accumulator 94 through a communication passage 154, and the communication passage 154 is provided with a check valve 156. This check valve 156 prevents the flow of liquid from the discharge passage 152 toward the pressure accumulation chamber 126, but the piston 122 of the charging accumulator 94 has a valve opening protrusion 1.
58 is provided, and this valve opening protrusion 158 opens the check valve 156 when no liquid is stored in the pressure accumulation chamber 126 and the piston 122 is in its original position. In addition, the valve opening protrusion is check valve 1.
It is also possible to provide it on 56 valves.

In the hydraulic brake device configured as described above, when a sufficient amount of fluid is stored in the high pressure accumulator 70, the pump motor 80 is stopped and the charging accumulator 94 is in the state shown in FIG. be.

When the hydraulic pressure of the high-pressure accumulator 70 decreases to the lower limit hydraulic pressure and the pump motor 80 is started, the charging pump 92 and the high-pressure pump 96 start operating at the same time. The charging pump 92 starts pumping action at the same time as the start of operation and supplies liquid to the charging accumulator 94. However, since the check valve 156 of the high-pressure pump 96 is in an open state, the discharged liquid flows through the communication path. 154 to the charging accumulator 94, and does not perform any substantial pumping action at the beginning of operation. Therefore, it is avoided that an inertial load and a load based on hydraulic pressure are simultaneously applied to the pump motor 80 at the same time as the pump motor 80 is started, and the pump motor 80 can be made small, resulting in improved durability.

Since the discharge amount of the charging pump 92 is set to be a certain amount larger than the sum of the discharge amounts of the two high-pressure pumps 96, the amount of liquid in the charging accumulator 94 gradually increases as the operation continues. As a result, if the piston 122 retreats a certain distance, the valve opening protrusion 158
is separated from the check valve 156, the check valve 156 blocks the communication path 154, and from then on, the high-pressure liquid discharged from the high-pressure pump 96 is discharged from the discharge port 100, and the pump device 76 substantially performs no pumping action. move to the state where it is done.

The amount of liquid stored in the high-pressure accumulator 70 increases,
When the hydraulic pressure reaches the upper limit hydraulic pressure, the pump motor 80 is stopped. At this point, the piston 122 of the charging accumulator 94 is in the retracted position and the check valve 156 is closed, so high pressure fluid is trapped in the high pressure fluid passage 74 and high pressure is applied to the high pressure rubber hose 78. It's working. However, since the charging accumulator 94 is provided with an orifice 132 as a leakage means, the liquid in the pressure accumulation chamber 126 gradually leaks into the low pressure chamber 128.
The piston 122 eventually returns to its original position. As a result, the valve-opening protrusion 158 provided on the piston 122 opens the check valve 156, allowing the high-pressure liquid trapped within the high-pressure liquid passage 74 to flow out to the charging accumulator 94 side. The hydraulic pressure in the high pressure liquid passage 74 is eliminated. While the pump device 76 is stopped, high hydraulic pressure can be prevented from continuing to act on the high pressure rubber hose 78.

Although one embodiment of the present invention has been described in detail above,
This is literally an example, and the present invention can be implemented in various other forms with various modifications and improvements based on the knowledge of those skilled in the art.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing a part of an anti-lock type hydraulic brake device equipped with a high-pressure hose protection type hydraulic pressure supply device according to an embodiment of the present invention. FIG. 2 is a front cross-sectional view showing details of a pump device that constitutes the main body of the hydraulic pressure supply device in FIG. 1. 70: High pressure accumulator, 72: Check valve, 7
4: High pressure liquid passage, 76: Pump device, 78: High pressure rubber hose, 80: Pump motor, 92: Charging pump, 94: Charging accumulator, 96: High pressure pump, 102: Housing, 1
04: Plunger, 112: Suction passage, 114:
suction valve, 116: discharge valve, 118: charging passage, 120: housing, 122: piston,
126: Pressure accumulation chamber, 130: Relief passage, 13
2: Orifice, 140: Housing, 142:
plunger, 148: suction valve, 150: discharge valve,
152: Discharge passage, 154: Communication passage, 156: Check valve, 158: Valve opening protrusion.

Claims (1)

[Scope of Claims] 1. A high-pressure accumulator that stores liquid at high pressure and supplies it to the target device as needed; A part of the high-pressure hose is formed of a flexible high-pressure hose, and one end passes through a first check valve to the high-pressure accumulator. a high-pressure liquid passage connected to the other end of the high-pressure liquid passage, a high-pressure pump connected to the other end of the high-pressure liquid passage and supplying liquid to the high-pressure accumulator; In a hydraulic pressure supply device including a piston-type charging accumulator that supplies liquid to a pump, and a charging pump that supplies liquid to the charging accumulator, the liquid stored in the charging accumulator is A leakage means for leaking small amounts of liquid is provided, and the high-pressure liquid passage and the charging accumulator are communicated through a communication passage, and the flow of liquid from the high-pressure liquid passage toward the charging accumulator is blocked through the communication passage. a second check valve is provided, and in a state where liquid is not stored in the charging accumulator in either one of the piston of the charging accumulator and the valve element of the second check valve. This is a high-pressure hose protection type hydraulic supply device, characterized in that it is provided with a valve-opening protrusion that opens a second check valve.