JPS5911968A - Electrical drive power steering device for vehicle, provided with assist device for rotation of oil pump - Google Patents

Abstract

PURPOSE:To make the rotation of a steering wheel satisfactory and to prevent a hitch phenomenon in steering feeling from being brought about, by rising up the rotation of an oil pump in accordance with the rate of steering with the use of the line of rotation of a vehicle speed sensitive base. CONSTITUTION:A steering wheel 1 is operatively connected through a steering shaft 2 to a control valve 3 having its inlet side connected to both supply port P and return port T, and its outlet side connected with either one of both chambers in the cylinder of a power actuator 6 through a bypass valve 5. One terminal of a motor 7 for driving the oil pump 4 is connected to a power supply 9 through a controller 8. The outputs of a vehicle sensor 10 and a steering sensor 11 which is disposed in the rotation part of a control valve 3, are electrically connected to the controller 8.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rotational force control of an electric electric ξ worst steer 1 hour per month oil pump, and more specifically, G'f-1
Regarding the electric/miso-steering device part θ) for a car that divides the oil pump discharge amount according to the steering angular velocity sensitive boost based on the steering wheel in addition to the vehicle speed sensitive boost based on the vehicle speed sensor. Zuro.

In general, when the vehicle speed is zero (・ means low-speed vehicle driving), the number of times that steering is required increases and a large amount of steering force is required; It is possible to reduce the assist effect of the steering force and reduce the amount and pressure of the oil rotated by the motor, the oil volume and pressure of the 1' large moving shaft discharged from the pump.
Ru.

In order to properly set the steering force, which is an important function of power steering, in order to generate the appropriate torque for the steering fI'e. Reduce the amount of ξ-war assist to give a sense of response, and increase the amount of leave and thrust when making sudden and violent maneuvers.
It improves the sharpness of the snake and reduces the steering force. In this way, when driving at low speeds, the amount of hydraulic oil supplied is increased to make steering wheel operations easier, and when driving at high speeds, the amount of hydraulic oil is decreased to make the same operations heavier, thereby stabilizing driving.・S-worst steering installation is conventionally known. In addition, the Power 3 steering system generates a control signal according to the steering angle, steering speed, and torque of the steering link wheel by the operator, and applies an assist force in accordance with the steering only when the steering is performed using this control signal. Conventionally known.

In the former, the vehicle speed-sensitive rotation of the oil pump is obtained using only a vehicle speed sensor, and in the latter, the steering-sensitive rotation is obtained using only a steering sensor. In devices with such sensitive characteristics, it is possible to avoid the occurrence of near-negative pressure (heavy steering feeling, so-called stuck phenomenon) due to insufficient amount of hydraulic oil discharged from the oil pump during high-speed driving. Na℃・.

The object of the present invention is to control the oil pump at the steering speed from the vehicle speed-sensitive base rotation line, so that the amount of hydraulic oil discharged from the oil pump can be obtained by rotating the oil pump in one rotation according to the vehicle speed. Improvement 11: To provide a rotational assisting device for an oil pump for electric/ξ power steering by improving the rotation speed so that the oil pump starts up and rotates as quickly as possible, thereby preventing the phenomenon of getting caught in the sense of performance.

Another object of the invention is to reduce the low speed of the oil pump 0 by using the output pulse of the steering sensor, the output pulse of the vehicle speed sensor, a busy OR circuit, and an OFF delay timer that delays the assist signal output from the OR circuit. VC provides an electric power steering device that can maintain vehicle speed-sensitive assist rotation while driving by shifting the pace la 1 rotation to vehicle speed-sensitive assist rotation and maintaining the assist rotation during the off period of both wheels. 1- It's a loco.

In order to achieve the above objectives, the present invention has the following features:
ξThe oil pump for worst steering uses a vehicle speed sensor (uses a steering sensor that responds to the steering angular velocity and uses a steering sensor to respond to the acceleration rotation by sensing the steering angular velocity). More specifically, when the steering speed is slow, the oil pump's output is increased in response to only the vehicle speed as before, and when the steering speed suddenly changes. In order to deal with this, in response to a sudden change in steering speed, the motor is moved above the preset vehicle speed-sensitive assist rotation line corresponding to the steering speed; 1. In other words, conventionally, when the vehicle is not being steered at an extremely low speed, the motor is rotating at an extremely low speed, in other words, the warming amplifier is rotating, and by steering at this time, the vehicle speed is adjusted according to the vehicle speed while the vehicle is running. It is known that responsive reinforcement was used, but what is uninvented is that when the steering is done, the pump rotational output is changed to 2 degrees Celsius and low speed rotation. The oil pump is constantly placed in a vehicle speed-sensitive rotation state by increasing the rotation speed to the vehicle speed-sensitive acceleration rotation line, and the pump rotation output increases along the preset steering angular velocity acceleration rotation line according to changes in the steering angle and steering speed. be configured to do so.

An embodiment of the electric vehicle electric vehicle according to the invention will be described below with reference to the drawings.

Figure 1 does not show an example of the uninvented steering system.
1 is the control valve 6 via 2 steering shafts
Please be operatively connected. The human power side of the control valve O is the oil pump 4's supply i''vs, I cell'P and 0ζ.
The outputs of the control valves are connected to the return ports T, respectively, and the output of the control valves is transmitted through the If it is not necessary, the power actuator 6σ is connected to either one of the two chambers of the cylinder. The oil pump 4 is driven by one terminal of the motor 7 (connected to a power source 9 such as a battery or alternator σ via the controller 8) and the other terminal (grounded).

The output of the vehicle speed sensor 10 and the force that changes the control valve σ) and the steering sensor 11 σ) installed in the rotating part are as follows:
An embodiment of the configuration of the controller 8 shown in FIG. 1 is shown in FIG. 2. In FIG. 2, the 3 pulse output of the steering sensor 11 is expressed by the peak-to-peak direct Hall 1-' pulse shaper 1 (in this embodiment, the pulse amplitude value is used, or the frequency-' voltage conversion method is used. ) and the first of the OR circuit 12
Also, the pulse output of the vehicle speed sensor 10 is connected to the frequency voltage/voltage converter (F/V converter) 14 and the second human power of ○R12. The outputs of the pulse shaper 16 and the F'/V converter 14 are both sent to the comparator circuit 1.
Be connected to 8. The output of the comparator circuit 18 is connected to the motor 7, which drives the oil pump, via a .xi.1 pulse modulation (PWM) amplifier 19. OR time! The output of the clock 12 is connected to a timer 15 which sets a delay time during the off time.

The operation of the circuit shown in FIG. 2 will be explained in the order of the arrows with reference to FIGS. 6 and 4. In FIG. 6, the pulse output X of the steering sensor 11 appears for a short time in the time direction of the horizontal axis during steering, and then lasts for the set delay time of the timer 15, and the pulse output ¥ of the ta sensor 10 is , in response to the increase in vehicle speed, the current is shortened for a short time in the direction of time on the horizontal axis, and continues for the delay time set by timer 15.Here, 7 mils is output from both sensors. 12, the output of timer 15 is the individual pulse output X';! f) ro (. is Yσ) produces a delayed output 2 even after it disappears. operation fl
If l'1'- is performed frequently or as the vehicle speed increases, the delayed output Z will appear continuously as time passes, but within the delay time X or Y-ξ There is no time and time (it is interrupted as indicated by W).

As shown in FIG. 4, the output signal of the timer 15 (one level signal at low speed) obtained during low-speed base rotation is obtained from the triangular wave oscillator 17, and the triangular wave signals are compared for each triangular wave signal as a reference signal. The conversion output σ corresponding to the vehicle speed is also applied from the F/V converter 14 to the comparison circuit 1.
Combined with the 14'J force signal X of ξNorth shaping-16 at 8. In this way, the controller 8 generates a pulse width modulated and amplified pulse signal d as the output of the amplifier 19, which has a steering angular velocity sensitivity characteristic and a vehicle speed sensitivity characteristic characteristic. The signal is supplied to the motor 7 as a motor drive signal e through a smoothing circuit (not shown).

The running characteristics of the vehicle to be realized by the electric puff steering device shown in FIGS. 1 to 4 will be explained below with reference to FIGS. 5 to 6.

FIG. 5 shows the relationship between the rotational output of the oil pump (vertical Il!llI) and the vehicle speed (horizontal axis) at 7 knots with no steering. For example, 1. When a car is stopped at a traffic signal or is running at a very low speed, the oil pump's rotational output is maintained at approximately 0% and is below the non-steering low speed rotation line L1, and then when the vehicle speed starts to increase. The rotational output of the oil pump immediately increases to approximately 100%,
Furthermore, as the vehicle speed increases, the required rotational output of the oil pump decreases along the vehicle speed-sensitive assist rotation line L2. All of these changes occur in the oil pump's normal rotational range.

Figure 6 shows the rotational output of the oil pump in the steering state (membrane of vertical (咄) and -content (1"l!lI+))]
Indicates the person in charge. As shown, the vehicle speed is approximately 5 C/cm/H.
In the low speed base rotation region up to 1, the OR circuit 12
○F' by the delay timer to turn off the output curls.
By delaying F, the rotational output of the oil pump will remain at about 10% line for a while, but timer 1
As the delayed output signal Z disappears, the rotational output of the oil pump decreases.

By the way, in the driving characteristics shown in FIGS. 5 and 6, when the vehicle speed exceeds a low speed such as 5 C/cm/H:ll, the rotational output of the oil pump increases to the vehicle speed sensitive assist rotation line L2. , the output of the steering sensor 11 is set to be ready to assist the rotation of the pump at any time in response to a change in vehicle speed, and to obtain additional rotation during sudden steering. Pulse shaper 1 is output according to the pulse amplitude value.
Based on the output signal X of LO, a group of steering angular velocity acceleration rotation lines L2, L3.

It is assisted by either L4 or L5. In Figure 6,
The steering angular velocity auxiliary rotation line L2 corresponds to the vehicle speed sensitive auxiliary rotation line L2 in FIG.

The driving characteristics when the vehicle is started from a stopped state and low steering is performed are mainly explained with reference to Figures 2 and 6. (- Well, the vehicle speed increases from the stopped state to about 5 Ck, m/H:] (
In a slow steering state, the pulse shaper 15 is activated at the same time as starting.
inputs the voltage pulse output signal of the steering sensor 11 and generates an output signal The comparison circuit 18 compares and adds up the voltage output signal from the timer 15, and the rotational output of the oil pump increases from 30% to 100% in the low speed base rotation region.

At this time, when a constant steering condition is maintained such as when traveling on a one-page line course or going up a ramp way, the pulse output X of the steering sensor 11 becomes zero, but the pulse output X of the vehicle speed sensor 10 From the output Y, a rotational output of the oil train pump corresponding to the vehicle speed at that time is obtained, and the rotational output of the oil pump decreases as the vehicle speed increases along the vehicle speed-sensitive assist rotation line L2. For example, if you turn the steering wheel suddenly (quickly),
A negative force for steering is applied to the oil pump 4 via the control valve 6, and this load causes the output of the motor 7 to fluctuate. Therefore, the oil pump 4's discharge jfu K is insufficient, so the steering wheel 1
The steering wheel becomes heavy and the steering sensation becomes discontinuous. In order to avoid such a phenomenon, the pulse output X of the steering sensor 11 is input, and the filter pulse shaper 16 generates an output signal having a field of view based on the change in the steering condition described above. Since a higher voltage output is produced during steering, the comparator circuit 18 is connected to the steering angular velocity acceleration rotation lines L, L.
4. A signal is output from among the L5m angular velocities [d, e, q/sec:] such that an auxiliary rotation line corresponding to the rapid steering continuous speed can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of an electric power steering device according to the invention. Figure 2 I, the fruit of the controller in Figure 1'm f+
7 is a block circuit diagram showing ll. FIG. 5 is a signal waveform diagram showing each pulse output of the steering sensor and the vehicle speed sensor and a delayed output as a logical sum of the pulse outputs. FIG. 4 is a signal waveform diagram for explaining the operation of the circuit of FIG. 2. FIGS. 5 and 6 show vehicle running characteristic curves for explaining the oil pump rotation assisting operation of the electric power steering device according to the present invention. (Explanation of symbols) 8...Controller 10...Vehicle speed sensor 11
...Steering sensor 12...OR circuit 13・Pulse shaper 14・
・Frequency voltage converter (F/V converter) 15, OFF
Delay timer 17 - Triangular wave oscillator 18... Comparison circuit 19... Pulse width modulation amplification delay L1... Non-steering low speed base rotation line L2... Vehicle speed sensitive assist rotation line (steering angular velocity base assist rotation line) L3. L4. L5... Steering angular velocity acceleration rotation line σ) Figure 4°

Claims (1)

[Claims] (1) A motor actuator driven by a motor. −
An oil pump that supplies hydraulic oil to the motor, a steering sensor that is installed in the rotation system of the control oil pump that controls the supply of hydraulic oil and that detects the steering angular velocity of the steering wheel, and a vehicle speed that detects the vehicle speed. a controller that receives a steering sensor θ) output signal and an output signal of the vehicle speed sensor and generates an output signal for controlling the rotation of the motor, and the controller has a preset vehicle speed sensitive force [ ] An electric power steering device for a vehicle, characterized in that a signal for applying a steering angular velocity auxiliary rotation exceeding the rotational speed in is configured to be added to the output signal of the controller. (2. The electric/ξ power steering device according to claim 1, wherein the output of the steering sensor and the output of the vehicle speed sensor are transmitted through an ○R circuit to produce a delayed output by a timer. The apparatus is characterized in that the delayed output is configured to increase the rotational output of the oil pump in the low-speed rotational range by the output of either of the above-mentioned two parts. (3) Claim No. 2. The electric power steering device according to item 2, wherein the controller generates a signal having a duration and amplitude formed in accordance with the rotation angle amount and speed of the steering wheel sensed by the steering sensor, and the above-described signal. The device is configured to increase the rotational output of the oil pump in response to the output signal of the vehicle speed sensor. (4) The electric power steering device according to claim 6. 1-, wherein the controller is configured to generate a series of pulse outputs to select any higher order of the group of steering angular velocity assist rotations based on changes in steering conditions; Tube making.