JPS5814144Y2 - Automotive power steering control device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a control device for power steering for automobiles.

It is known that when a car is driven at high speed, the frictional resistance between the tires and the road surface decreases, and the steering force becomes lighter.

Therefore, when driving a car equipped with power steering at high speed, the steering force becomes too light and the driver may feel unstable. The current situation is that even if it is a sacrifice, it is not equipped with power steering.

This idea was developed in light of these conventional circumstances, and it improves drivability by reducing the steering force at low speeds, similar to conventional power steering, and also improves drivability when driving at high speeds. By reducing the steering function, the steering force is increased to the extent that a sense of stability is felt, eliminating the sense of instability caused by too much steering force as in the past, and enabling stable and nimble driving at both high and low speeds. The present invention aims to provide an automotive power steering control device that can perform the following functions.

Hereinafter, this invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

A vane-type hydraulic pump 1, which constitutes an automobile power steering system together with an oil tank, a hydraulic booster, etc. (not shown), has vanes 2, 2. . . . A rotor 3 mounted so as to be freely protrusive and retractable in the radial direction, a drive shaft 4 that rotates and drives the rotor 3, a cam ring 5 that covers the circumferential surface of the rotor 3, and a shaft that supports the shaft 4. The body 6 covers one end surface of the cam ring 5, and a pressure plate 7 is attached to the body 6 so as to be movable in the axial direction so as to cover the other end surface of the cam ring 5. , . . . are brought into sliding contact with the inner circumferential surface of the cam ring 5, and the drive shaft 4 and the crankshaft of an engine (not shown) are interlocked and connected via an appropriate gear train.

The cam ring 5 has a suction port and a discharge port, as in the case of a conventional vane type hydraulic pump. The hydraulic oil stored in the hydraulic booster is supplied under pressure to the hydraulic booster, and the pressure of the hydraulic oil is prevented from becoming abnormally high at an appropriate position in the pressure supply path.
Of course, the JIJ valve is built into the housing.

The cam ring 5 and the body 6 are integrated with bolts or the like (not shown), and a pressure plate 7 attached to the body 6 so as to be freely movable in the axial direction is held elastically against the end surface of the cam ring 5 by a spring 8. There is.

On the opposite side of the rotor 3 sandwiching the pressure plate 7,
An electromagnetic device 9 is provided to attract the pressure plate 7 away from the end surface of the cam ring 5 against the tension of the spring 8, or the electromagnetic device 9 is fixed to a side cover of the pump (not shown). .

Additionally, a control device 10 is connected to the electromagnetic device 9, which operates the electromagnetic device 9 when the vehicle speed exceeds a certain speed.

For example, as shown in FIG.
2 and the output terminal of the generator 12 and the control element 130
By connecting the control terminal to the control terminal via the variable resistor 14, and connecting the output terminal of the control element 13 to the electromagnetic device 9 via the variable resistor 15, the alternating current generator is activated when the vehicle speed reaches a certain speed or higher. When the electromotive force of 12 exceeds a predetermined voltage, the control element 13 is made conductive to connect the power source 16 and the electromagnetic device 9,
Separate the pressure plate I of the hydraulic pump 1 from the end face of the cam ring 5, and! In addition, when the vehicle speed falls below a certain value of 1 and the electromotive force of the alternator 12 decreases, the control element 13 is reset to disconnect the power source 16 and the electromagnetic device 9, and the electromagnetic device 9 is restored to release the pressure plate 7 into a spring state. It is made to come into pressure contact with the end face of the cam ring 5 by the tension force of 8.

In addition, during the control operation as described above, by adjusting the variable resistor 14, the operation level (vehicle speed) of the control element 13 can be changed, and by adjusting the variable resistor 15, the voltage supplied to the electromagnetic device 9 can be changed. Since the electric power can be changed, the amount of movement of the pressure plate 7 (the distance between the cam ring and the pressure plate) can be changed, which is convenient, and at least one of the variable resistors 14 and 15 can be changed as necessary. If the switch function is maintained, the electromagnetic device 9 can be maintained in an inoperative state even when the vehicle speed exceeds a certain speed.

The control device 10 shown in FIG. 2 above is designed to continuously detect the vehicle speed, but as shown in FIG. 12 is provided, and the switch 12 and the control element 13 are connected via a manual switch 17, and the driver operates the manual switch 17 to perform high-speed operation (set the gear shift lever to the high-speed position). It's good for you.

In addition, in FIGS. 2 and 3, reference numeral 18 is a pilot lamp that indicates the operating state of the electromagnetic device 9.

Furthermore, in all of the embodiments described above, the electromagnetic device 9 is controlled to be switched into two stages: activation and deactivation.
By appropriately selecting the control element 13, the amount of current applied to the electromagnetic device 9 is gradually increased as the vehicle speed increases, and as the vehicle speed increases, the amount of current applied to the electromagnetic device 9 is gradually increased as the vehicle speed increases. Of course, it is also possible to do so.

When the above-mentioned preemption button is pressed and the vehicle speed is higher than a predetermined value, the electromagnetic device 9 is activated by a command from the control device 10 to move the pressure plate 7 to the cam ring 5 against the tension force of the spring 8. Separate (levitate) from the end face of.

Then, a gap is created between the end surface of the cam ring 5 and the pressure plate I, so the plate 73 whose end is covered with the rotor 3
,3. ......The degree of sealing of the space formed in between is reduced, and a portion of the hydraulic oil that is being pressurized in this space flows from the gap to a suction passage or an oil tank (not shown), etc. leak.

For this reason, the pressure and flow rate of the hydraulic oil supplied from the oil tank to the hydraulic booster via the hydraulic pump 1 decreases, and the output of the hydraulic booster decreases.

As a result, the steering force becomes heavier and stability at high speeds can be increased.

Note that even if the output of the hydraulic booster decreases as described above, the frictional resistance between the tires and the road surface is small at high speeds, so there is no difficulty in steering the vehicle.

However, when the vehicle speed is low and the frictional resistance between the tires and the road surface is large, the electromagnetic device 9 does not operate, and the pressure plate 7 is held in pressure contact with the end surface of the cam ring 5, causing the vanes 2, 2 to
．．・・・・・・Since the sealing degree of all the spaces formed between them is increased, high-pressure hydraulic oil is supplied to the hydraulic booster, and in order for the hydraulic booster to exert the specified output, the steering The operating force can be reduced, improving drivability.

As explained above, according to this invention, the pressure of the hydraulic oil sent to the hydraulic booster is adjusted to increase or decrease depending on the vehicle speed,
At high speeds, the output of the hydraulic booster is reduced to improve steering control performance, and at low speeds, the output of the hydraulic booster is increased to reduce steering effort and improve drivability.

In addition, in this invention, since the output of the hydraulic booster is increased or decreased by the hydraulic pump as described above, the power consumption of the hydraulic pump is reduced during high-speed operation, which has the secondary effect of reducing the load on the engine. It also has

Furthermore, since the pressure plate is held by a spring, if the pump discharge pressure becomes abnormally high due to an abnormality in the relief pulp, this pressure will push the pressure plate up from the end face of the cam ring against the spring. Since the hydraulic oil is released, there is no need to provide a safety valve or the like to avoid abnormally high pressure.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing an embodiment of this invention, and FIGS. 2 and 3 are control circuit diagrams of the same. 1...Hydraulic pump, 5...Cam ring, γ...Pressure plate, 8...
Spring, 9... Electromagnetic device, 10...
Control device.

Claims (1)

[Scope of utility model registration request] In an automotive power steering system equipped with a vane-type hydraulic pump that is rotationally driven by an engine, a pressure plate that covers one end surface of a cam ring that accommodates the rotor of the pump is mounted so as to be movable in the axial direction, and the pressure plate is attached to the cam ring. A spring that presses and holds the end face, an electromagnetic device that moves the pressure plate away from the end face of the cam ring against the spring, and a control device that operates the electromagnetic device when the vehicle speed reaches a certain speed or higher is provided. An automotive power steering control device characterized by: