JPS584672A - Detector for steered angle of steering wheel in automotive steering gear - Google Patents

Abstract

PURPOSE:To improve reliability of detecting a steered angle by receiving light emitted from a luminescent element which has well directivity as a steered angle sensor, at a light susceptible element via a rotary slits which is fixed to a steering shaft, to form pulses on the incidence basis. CONSTITUTION:When an ignition switch 21 is closed, a driving circuit D is actuated to make a luminescent element 15 luminous. Associated with turning of a steering wheel, a rotary disc 14 which is fixed to a steering shaft is turned to make successive facing of slits 14a to a luminescent element 15. Light, emitted from the luminescent element 15 passes through the slit 14a to a light susceptible element 16, for electrifying to generate a pulse at a load resistor 17. The number of the pulses, corresponding to that of the slits 14a which pass through, are inputted into a counter circuit C, subjected to wave forming in a Schmit circuit 18 and then displayed as a steered angle.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steering wheel angle detection device for a steering device for an automobile.

As a conventional steering angle detection device for a steering wheel, for example, a first steering angle detection device is used.
．． There is one shown in Figure 2. In the figure, 1 is a steering angle senna. The sensor 1 has a large number of N, 8 poles 2a on the periphery *
2b are alternately magnetized and coaxially fixed to the steering shaft 8, and a reed switch 5 is a magnetic sensing element that is sensitive to the magnetic poles of the magnet 4. Reference numeral 6 denotes a pulse generation circuit that outputs an output in response to opening and closing of the reed switch 5, and 7 a counter that counts pulses input from the pulse generation circuit 6 and displays this as a steering angle of the steering wheel. 8 is a power source such as a battery, 9 is an ignition switch, 10 is a handle, 11 is a jacket tube, and 12 is a reed switch mounting member.

With this configuration, the driver can
When the magnet 4 is turned 0, the magnet 4 rotates, and the reed switch 5 opens and closes according to its magnetic pole. Then, pulses corresponding to the number of openings and closings of the reed switch 5 are output from the pulse generating circuit 6 and input to the counter 7. The input pulses are counted by a counter 7 and output and displayed as a steering angle from the neutral position of the steering wheel 10.

However, with such a conventional steering wheel steering angle detection device, it is not possible to increase the accuracy and reliability of the detection and display of the steering angle beyond a certain level.

That is, if the number of magnetic poles of the magnet 4 is increased in order to improve accuracy, the reed switch f5 will malfunction due to the magnetic lines of force of the N and S poles 2m and 2b that are close to each other, so the resolution of the steering angle sensor 1 will be increased above a certain level. I can't.

Therefore, the accuracy of detection and display of the steering angle is poor, and there is a limit to miniaturization of the device itself.

In addition, with conventional devices, although the steering angle of the steering wheel 10 itself can be displayed within the above-mentioned limited accuracy, it is also possible to display the steering angle of the steering wheel 10 within the above-mentioned limited accuracy. It is not possible to detect and display whether or not the machine is disconnected.

This invention was made by focusing on such conventional problems, and as a steering angle sensor in a steering angle detection mechanism, light emitted from a light emitting element is passed through a slit in a rotary plate coaxially fixed to a steering shaft to a light receiving element. This system uses a steering angle sensor that receives the signal from the steering wheel and outputs it as a pulse, and displays the open/closed state of a switch that opens and closes in response to the components of the steering force transmission mechanism of the steering wheel with an indicator.
It is an object of the present invention to solve the above problems by using a steering wheel position detection mechanism together with the steering angle detection mechanism.

This invention will be explained below with reference to embodiments shown in FIGS. 3 to 7.

First, to explain the structure, the device of the present invention is composed of a steering wheel angle detection mechanism shown in Fig. 3.4 and a steering wheel position detection mechanism shown in Figs. 5-6.

In the above steering wheel angle detection mechanism (Fig. 3.4),
S is a steering angle sensor, D is a drive circuit that drives the steering angle sensor S, and C counts pulses emitted by the steering angle sensor S.
This is a counter circuit that displays this as the steering angle of the steering wheel.

The steering angle sensor S includes a non-transparent rotating plate 14 coaxially fixed to the steering shaft 18, a light emitting element 15, a light receiving element 16, and a load resistor 17. The light-emitting element 15 and the light-receiving element 16 are placed opposite to each other by sandwiching the sleeves 14a provided on the periphery of the rotary plate 140 at regular intervals corresponding to the steering angle from the neutral position of the handle 23. The pixel elements 15 and 16 are fixed to the jacket 23 via the mounting member 24 so as to face each other at a position H4a corresponding to a zero steering angle when the handle 22 is in the neutral position. Now, when the light emitted by the light emitting element 150 passes through one Surin H4a, the light receiving element 16 receives this and becomes energized by itself, and the current flows through the load resistor 17.
A pulse is generated by changing the Q.

This pulse is generated as many times as the number of slits 14 through which the light emitted by the light emitting element 15 has passed. In this case, the number of pulses generated is determined by the number of pulses generated by the light emitting element 15 when the handle 22 is in the neutral position.
This corresponds to the net number of slits H4a counted from the slit 14a with which the slits 14a are aligned. In other words, the steering angle when the turned steering wheel 22 is turned back is determined by the number of pulses corresponding to the steering angle of the turned steering wheel 22 being counted by a counter circuit C, which will be described later. is subtracted from the number and displayed as the net steering angle.

The light emitting element 15 is made of a material having as good directivity as possible, and the spacing between the sleeves N4a is made as small as possible so that the light from the light emitting element 15 does not leak from the adjacent sleeves 14&.

The counter circuit C is composed of a Schmitt circuit 18 that shapes the pulse and pulse waveforms generated by the steering angle sensor S, and a counter 19 that inputs and counts the shaped pulses and outputs and displays the pulses as a steering angle. There is.

20 is a power source such as a battery, 21 is an ignition switch, and 22a is a handle cover that prevents light from entering.

Next, in the above-mentioned steering wheel position detection mechanism (Fig. 5.6), W, , W are provided protruding from the pitman arm 25 constituting the steering force transmission mechanism of the steering wheel 22, and closed by being pressed by the nine operating rods 26, A pair of switches that open when the pressure is released.
It is attached and fixed to the vehicle body. R1, R, are indicator lamps that turn on when the switches W, , W are closed and turn off when they are opened.

Therefore, in this mechanism, when the handle 22 is turned to the right by more than a predetermined angle, the pitman arm 25 is rotated to the right, in the direction of the finger fiR, and the swing f W + is closed.
Only the lamp R8 lights up, and on the other hand, if the handle 22 is turned to the left by more than a predetermined angle, the pitman arm 25 turns to the left, that is, to the left, and the switch W! is closed, and only lamp R is lit. These lamps R1, R, are installed at positions where they can be visually recognized at the same time as the steering wheel angle display in the steering wheel angle detection mechanism. ■ is a power source such as a battery.

FIG. 7 shows the lamp RI +R as the above indicator.
This is an example in which the switches W, , W4 that turn on the lights are opened and closed by a stepped portion 28 formed on the rack 27 constituting a rack-binion type steering force transmission mechanism.

In this structure, the pair of switches W, W4 are attached to the dust cover 29 via attachment members 29a.

The racks 21 are installed at fixed intervals, and when the handle is turned to the right by more than a predetermined angle, the rack 21 will move to F.
direction, and is pressed by the stepped portion 2B, causing the switches W,,W
, are both closed, and if the 71 handle is turned to the left by more than a predetermined angle, the rack 21 will move in the G direction, and it will be released from the stepped part 28, and both switches Ws and W will open, and the no. 71 handle will be in the neutral position. When placed in the position, only the switch W3 is pressed by the stepped portion 28 and closes.

The feature of this structure is that since the opening/closing pattern of the switches W, , W, is different from that shown in FIG. 6, there is a difference in the display pattern of the handle position by the lamps R1eRl.

Next, the action will be explained.

First, in Figure 3.4, Igni V Yon Suidde 2
1 is closed, the drive circuit is activated and the light emitting element 15 emits light. Next, when the driver turns the steering wheel 22 in the neutral position to the right, the rotary plate 14 fixed to the steering shaft 13 rotates clockwise at the same time, and the sleeves H4a sequentially turn the light-emitting elements starting from the first right-hand side sleeve H4a. 15. Then 1 light emitting element! The light emitted by 5 is
The light passes through 4a and enters the light receiving element 16, and the light receiving element 16 becomes energized. When the power is turned on.

The current passes through the light receiving element 16 and flows into the load resistor 17, generating a pulse.

The pulses generated according to the number of passing N4a are:
is input to the counter circuit C, and its V unit circuit 18
After the waveform is shaped by the counter 19, it is counted by the counter 19 and output and displayed as a steering angle.

When the steering wheel 22 is turned to the left, the counter 19 subtracts the pulse count generated in accordance with the steering angle from the original count as described above. Then, the resulting net count value is output and displayed as nine steering angles accordingly.

The same applies to the case where the handle 22 is turned to the left.

On the other hand, in Fig. 5.6, when the nozzle 22 in the neutral position is turned to the right as described above and rotated by a preset angle, the pitman arm 26 rotates in the R direction and its Actuation rod 26 closes switch W1. Then, at the same time as the counter 19 displays the steering wheel angle, a lamp R located at a visible position lights up to display the position of the steering wheel 22, that is, the steering direction.

When the handle 22 is turned back to the neutral position, the switch W opens and the lamp R8 goes out. When the handle 22 is turned to the left, the switch W closes through the process described above and the lamp R3 turns on. The steering direction of the steering wheel 22 is displayed.

As shown in FIG.
The operation in the case where the structure is opened and closed at 7 and 9 is essentially the same as that described above.

Although not shown, the rotary plate 14 has a structure in which multiple slits are provided concentrically, the slits are provided in a straight line in an open-circuit shape, and multiple pairs of light-emitting elements and light-receiving elements corresponding to these slits are placed opposite each other. In this way, the reliability of the steering angle sensor can be further improved. Furthermore, if the slits provided in a straight line are slightly shifted at regular intervals, the resolution of the steering angle sensor can be improved.

Ti, although not shown, the above-mentioned swing? W,,W,.

By providing not only one pair but many pairs of switches that open and close sequentially for each unit steering angle, not only the steering direction of the steering wheel but also the steering angle can be displayed simultaneously.

As described above, the present invention is used as a steering angle sensor in a steering angle detection mechanism. Light emitted from a light emitting element with good directivity is fixed to a steering shaft and passed through small and closely spaced slits in a turning plate to a light receiving element. Since we used a steering angle sensor that can receive this signal and output it as a pulse, the resolution of the steering angle sensor can be increased.
Therefore, the detection accuracy of the steering angle of the steering wheel can be improved.

In addition, this invention uses a switch that opens and closes in response to the steering force transmission mechanism components of the steering wheel as well as the steering wheel steering angle detection mechanism to display the steering direction of the steering wheel by lighting a lamp that is an indicator. Since it is configured to use a handle position detection mechanism that can rotate the handle, it is possible to simultaneously detect and display how many times the handle has turned in either direction, left or right.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional steering angle detection device for a steering wheel.
2 is a cross-sectional view of a main part showing the structure of the steering angle sensor in FIG. 1, FIG. 3 is a configuration diagram of a steering wheel steering angle detection mechanism that constitutes the present invention, and FIG. 4 is a sectional view of the steering angle sensor in FIG. 3. 5 is a configuration diagram of the handle position detection mechanism constituting the present invention, FIG. 6 is a perspective view showing the mounting structure of the switch in FIG. 5, and FIG. 7 is the handle position detection mechanism. FIG. 3 is a perspective view showing another mounting structure for the switch in FIG. S...Steering angle sensor C...Counter circuit D...Drive circuit 14...Rotary plate 14a...・Slit 15...Light emitting element 16...Light receiving element w,,w,,w,,w,...Switch 25...
・Steering force transmission mechanism R,, R,...indicator

Claims (1)

[Claims] It consists of a steering wheel steering angle detection mechanism and a steering wheel position detection mechanism, and the steering wheel steering angle sensing mechanism detects the light emitted from the light emitting elements that pass through slits provided at regular intervals on a rotary plate that rotates coaxially when the steering wheel is operated. A steering angle sensor that receives light with a light-receiving element and outputs it as a pulse, a drive circuit that drives the steering angle sensor, and a counter circuit that inputs and counts the pulses and displays this as a steering wheel steering angle. The steering wheel position detection mechanism includes a switch that opens and closes in response to a steering force transmission mechanism of the steering wheel, and an indicator that displays the open and closed state of the switch. A steering angle detection device for a steering wheel in a device.