JPS6318531B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention suppresses output changes caused by disturbances such as steering wheel movement at low speeds in the output of a sensor that detects the steering direction, and suppresses only the original output changes when changing direction. The present invention relates to a steering wheel turning angle detection device for a vehicle that outputs a steering angle.

There is a device that detects the steering angle of a vehicle and performs various controls depending on the steering angle. For example, there is an automatic turn signal canceling device that detects the steering wheel turning angle, determines that the vehicle has finished cornering when the steering wheel turning angle satisfies a certain condition, and automatically stops the operation of the turn signals.

When detecting the steering wheel turning angle of a vehicle as a signal using a potentiometer, in addition to the signal related to the steering wheel turning angle that represents the original direction change, a signal representing alternating steering wheel movements with small amplitude is output. This becomes a noise component, and this noise component becomes particularly large at low vehicle speeds. Therefore, simply connecting a potentiometer between a movable part such as a steering wheel and the vehicle body cannot eliminate the above-mentioned noise component, and an automatic turn signal canceling device or the like that operates in response to a signal related to the steering wheel turning angle cannot be used. There was a problem with malfunctions. In view of the above-mentioned disadvantages, the present inventor has created the present invention in order to effectively solve the problems.

It is an object of the present invention to provide a steering wheel turning angle detecting means for detecting a steering wheel turning angle and outputting a signal representing the steering wheel turning angle, an integrating circuit for inputting an output signal from the steering wheel turning angle detecting means, and a steering wheel turning angle detecting means for detecting the steering wheel turning angle. A switch means provided between the means and the integrating circuit, and a vehicle speed detection means for detecting a vehicle speed and outputting a signal representing the vehicle speed, and a closing time per unit time of the switch means is provided for detecting the vehicle speed. By making the length longer as the vehicle speed increases based on the output signal from the means, noise components generated by steering wheel movements unrelated to direction changes at low vehicle speeds can be removed, and the vehicle can truly change direction. The present invention is characterized by providing a steering wheel turning angle detection device for a vehicle that outputs only a signal representing the steering angle.

Therefore, an object of the present invention is to use it in a device that operates using the turning angle of a steering wheel, such as an automatic turn signal cancel device, to output only the signal generated by the steering wheel operation for the original steering operation. It is an object of the present invention to provide a steering wheel turning angle detection device for a vehicle that can automatically cancel the operation of a turn signal and thereby eliminate the influence of disturbance in the automatic turn signal cancel device.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a diagram of a steering direction detection circuit (handle turning angle detection device) according to the present invention. 1 is a terminal connected to a battery, and 2 is a potentiometer. The potentiometer 2 detects the position (steering direction of the steering wheel) of a movable part including a steering wheel with respect to the vehicle body, and outputs this as a predetermined voltage.
The voltage taken out by the potentiometer 2 is input to an amplifier 3, and output to the next stage via an integrating circuit A consisting of a switch 4, a resistor 5 and a capacitor 6, and an amplifier 7.

The time constant of integrating circuit A is determined by resistor 5 and capacitor 6.
The number of on-operations of the switch 4 is controlled by the functions described below.
Further, the switch 4 is formed of a semiconductor or the like.

The on/off operation of switch 4 is performed by vehicle speed detection circuit B.
is controlled by the output state of Vehicle speed detection circuit B
is constructed as follows. A reed switch 8, a resistor 9, and a capacitor 10, which are normally used for distance measurement in a vehicle, are connected at point a as shown in the figure, and one terminal of the capacitor 10 is connected to the grounded resistor 11 and the base of a transistor 12. The collector of the transistor 12 is connected to the resistor 13 and the capacitor 14 at point b, and further connected to the negative input of the amplifier 15.
A voltage divided by resistors 16 and 17 is applied to the positive input of the amplifier 15. The output of the amplifier 15 is applied to the switch 4, and the switch 4 is turned on when the output is at a high level, and turned off when the output is at a low level. Terminal 18 is a terminal connected to a battery.

The operation of the above circuit will be explained below.

When the vehicle is stopped, the switch 8
It is either on or off.
Therefore, the capacitor 10 is in either a fully discharged state or a fully charged state, and therefore the transistor 12 is in an off state. When transistor 12 is in the off state, capacitor 14
is in a charged state via the resistor 13, and the voltage at point b, which is a preset charging voltage, is applied to the negative input of the amplifier 15 at a value higher than the voltage applied to the positive input. Therefore, the output of the amplifier 15 becomes a low level state, and the switch 4 is kept in the OFF state. As a result, the potentiometer 2 and the integrating circuit A are completely disconnected from each other, and the output of the amplifier 7 is connected to the point c. A potential of will appear. At this time, the potential at point c is maintained at the voltage from potentiometer 2 when switch 4 was on. As long as the switch 4 is off, the potential at point C will not change no matter how much the voltage output from the potentiometer 2 changes.

When the vehicle is running, switch 8 is on,
The OFF operation is repeated, but when the switch 8 changes from the ON state to the OFF state, current flows to the base of the transistor 12 via the resistor 9 and the capacitor 10, turning the transistor 12 ON for a short time.
If transistor 12 is turned on for a short period of time, capacitor 14 is discharged during that time, and after that time capacitor 14 begins to be charged via resistor 13.
Therefore, capacitor 14 discharges and resistors 16, 17
The output of the amplifier 15 is maintained at a high level for a certain time t until the potential at point b reaches the positive input voltage determined by . While the output of amplifier 15 is at a high level, switch 4 is on. Conversely, when the switch 8 changes from the off state to the on state, the charge stored in the capacitor 10 is discharged through the switch 8, etc., so the transistor 12 remains in the off state until the switch 8 changes from on to off again. I will do it.

Since the on/off operation of the switch 8 becomes faster in proportion to the vehicle speed, the number of times the amplifier 15 becomes high level, that is, the number of times the switch 4 is turned on, is proportional to the vehicle speed. Note that the time t when the output of the amplifier 15 reaches a high level depends on the resistors 13, 16, 17 and the capacitor 1.
4 and is unchanged. The above action can be expressed as a second
The figures are indicated by a and b, where a is a diagram in a stopped state, b is a diagram in a low speed state, and c is a diagram in a high speed state. In the figure, the horizontal axis indicates elapsed time, and in the vertical direction, the upper row shows the operating state of switch 8, the middle row shows the output state of amplifier 15, and the lower row shows switch 4.
It is a diagram of the operating state of.

The operation of the circuit according to the present invention as described above has the following meaning.

If the resistance value of the resistor 5 and the capacitance value of the capacitor 6 constituting the integrating circuit A are R ₁ and C ₁ respectively, the time constant is given by R ₁ C ₁ , and the time constant R ₁ C ₁ and the output of the amplifier 15 are The relationship between the time t and the time that t maintains a high level is
Set so that R ₁ C ₁ ≫t.

The switch 4 is interposed between the potentiometer 2 and the integrating circuit A, and the temporal frequency of the ON operation of the switch 4 is changed depending on the vehicle speed, so that when the vehicle speed is high, the switch 4 is ON. Since the temporal frequency also increases, the voltage detected by potentiometer 2 will change to C without attenuation.
However, when the vehicle speed is low, the frequency at which the switch 4 is turned on is also low, so if a relatively high voltage is detected by the potentiometer 2 in a short period of time due to the movement of the steering wheel at low vehicle speeds. Even if the voltage is input to the integrating circuit A through the switch 4, the probability that this voltage is input to the integrating circuit A through the switch 4 is low. The time t during which the switch 4 remains on is determined by the integration circuit A
Since the time constant R ₁ C ₁ is set extremely short, the voltage detected by potentiometer 2 does not reach the saturation state of capacitor 6, and the voltage detected by potentiometer 2 is integrated It will be attenuated in circuit A. Therefore, at low vehicle speeds, the switch 4 and the integrating circuit A constitute an attenuator, and almost no voltage change detected by the potentiometer 2 is transmitted to point C.

In other words, the time constant of the integrating circuit A composed of the resistor 5 and the capacitor 6 is the operating characteristic of the switch 4,
In other words, the appearance changes depending on the vehicle speed. That is, at low vehicle speeds, the time constant of the integrating circuit A appears to be large, and as the vehicle speed increases, the time constant gradually approaches the value of R ₁ C ₁ determined by the resistor 5 and capacitor 6. Become.

Next, an automatic turn signal cancel device using the present invention will be explained with reference to FIGS. 3, 4, and 5. Fig. 3 is a circuit diagram of the automatic blinker canceling device, Fig. 4 is a diagram of the course of the vehicle when turning left, and Fig. 5 is a diagram of the output of the vehicle speed potentiometer and the output of the steering direction detection circuit corresponding to Fig. 4. FIG. When turning on the turn signal switch 19 to operate the left turn signal lamp at point d in Fig. 4,
Turn signal lamp 20 flashes and switch 2
The collector of the transistor 22 is connected to the solenoid 23 via the solenoid 23 . The other terminal of the solenoid 23 is connected to a battery. At this time, transistor 22 is in an off state.

The potentiometer 2 is set so that the voltage increases when the handle is turned to the left, and the voltage decreases when the handle is turned to the right. The vehicle speed gradually decreases between e and f as it moves to the left side while decelerating.
The maximum value g among the 24 output voltages is diode 2.
6. Even if a fluctuation D (disturbance) in the output of the potentiometer 2 occurs due to the movement of the handle, for example, in a low speed state before point f, the fluctuation E in the output of the circuit 24 will result in an extremely small change (disturbance) in the output of the circuit 24 due to the above-mentioned action. emitter
(lower than the set voltage V between the bases), the transistor 27 is never turned on.

When the vehicle stops at point f and starts running again after a certain period of time and starts turning left, the vehicle speed after running rapidly increases to F, so the potentiometer 2 corresponding to the steering direction of the steering wheel is controlled by the action of the circuit 24. The change in the output voltage G of
5. After the direction change, when the steering wheel returns to the predetermined turning angle, a voltage difference of V is generated between the emitter and base of the transistor 27, as shown in I in FIG. 5c, so that the transistor 27 is turned on. When the transistor 27 is turned on, current also flows to the base of the transistor 22 via the resistor 28, turning the transistor 22 on. As a result, solenoid 2
3 to activate it, return the turn signal switch 19 and switch 21 to their old positions, and automatically cancel the operation of the turn signal lamp 20.

The above operation was for a left turn, but for a right turn, transistors 29 and 30 operate in the same manner as above. However, in this case, in order to generate a voltage difference V by comparing the minimum value of the voltage held in the capacitor 31 and the output voltage of the circuit 24 in the transistor 29, the connection of the circuit elements is changed as shown in the figure. Ru.

As is clear from the above description, according to the present invention,
a steering wheel turning angle detecting means for detecting a steering wheel turning angle and outputting a signal representing the steering wheel turning angle; an integrating circuit for inputting an output signal from the steering wheel turning angle detecting means; the steering wheel turning angle detecting means and the integrating circuit; and a vehicle speed detection means for detecting the vehicle speed and outputting a signal representing the vehicle speed. Since the signal length is originally configured to increase as the vehicle speed increases, it is possible to remove noise components generated by steering wheel movements that are unrelated to direction changes at low vehicle speeds, and output only signals that truly indicate direction changes. A steering wheel turning angle detection device for a vehicle can be obtained.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, FIG. 1 is a circuit diagram of a steering wheel turning angle detection device, and FIG. 2 is a diagram showing the operating state of the circuit elements, where a is a diagram at a stop and b is a diagram at a low speed. , c is a diagram at high speed, FIG. 3 is a circuit diagram of the automatic turn signal canceling device, FIG. 4 is a diagram showing the course of the vehicle, and FIG. 5 is a state diagram of the circuit elements of the automatic turn signal canceling device. A is a diagram of the vehicle speed, b is a diagram of the output of the potentiometer, and c is a diagram of the output of the steering wheel turning angle detection device. In the drawing, 2 is a potentiometer, 4 is a semiconductor switch, A is an integrating circuit, and B is a vehicle speed detection circuit.

Claims (1)

[Scope of Claims] 1. A steering wheel turning angle detecting means for detecting a steering wheel turning angle and outputting a signal representing the steering wheel turning angle, an integrating circuit inputting an output signal from the steering wheel turning angle detecting means, and the above-mentioned steering wheel turning angle. a switch means provided between the detection means and the integration circuit; and a vehicle speed detection means for detecting vehicle speed and outputting a signal representing the vehicle speed; A steering wheel turning angle detecting device for a vehicle, characterized in that the longer the vehicle speed is, the longer the steering wheel turning angle is based on the output signal from the detecting means.