JPS5838338B2 - How do you know how to do this? - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for displaying warnings of abnormalities in various parts of a vehicle such as an automobile.

In order to drive safely in a car, it is necessary to constantly monitor the state of each part such as brake oil level, battery fluid level, lubricating oil level, and cooling water temperature to maintain these in a normal state. A monitoring and display device called OK Monitor (trade name) is commercially available, which has sensors arranged in the vehicle, constantly monitors the output status of each sensor, and displays normal and abnormal conditions on the driver's seat.

In such devices, as the number of monitoring items and hence the number of sensors increases, the number of wires also increases accordingly.For example, a commercially available OK monitor with 11 monitoring items uses 11 or more wires.

In order to increase the driving safety ratio of automobiles, it is necessary to further increase the number of monitoring items, and in such a case, the amount of wiring becomes even more enormous.

Additionally, this type of monitoring device consists of sensors, a signal processing section that reads out the output status of each sensor, and a display section that displays the read results. Due to many constraints, the device needs to be as small as possible.

Therefore, it is conceivable to separate the display section and the signal processing section and install only the display section in the driver's seat, but in this case, unless some ingenuity is put into the signal transmission method, the number of signal lines equal to or greater than the number of sensors would be required. Put it away.

The present invention aims to improve this point and make it possible to transmit necessary information to the display section using an extremely small number of signal lines.

The display device of the present invention includes a signal processing section that includes a circuit that sequentially reads out the output states of sensors arranged in various parts of the vehicle according to address signals, and a signal sending circuit that sends out the address signal of the sensor that has detected an abnormality as an abnormality warning signal; A display section that includes a display corresponding to each sensor and receives the address signal to activate the display corresponding to the sensor that has detected an abnormality, and is disposed between the signal processing section and the display section. When the number of signal lines and a pair of power supply lines sufficient to transmit each bit of the address signal in parallel, and the readout line of the circuit for reading out the output state of the sensor reach the abnormal level, the operation starts. A first holding circuit that continues to flow a current from the power supply on the signal processing section side to the display section side through the power supply line for a certain period of time, and a first holding circuit that is provided corresponding to each display element of the display device and receives an address signal. The present invention is characterized in that it has a second holding circuit that maintains a path through which current flows from the power supply line to the corresponding display element for a certain period of time even after the power supply line disappears. Explain.

1 and 2 show a display device according to the present invention, the former showing its signal processing section STS and the latter showing its display section DIS.

Both are connected by seven conductive wires including signal lines l1 to l5 and power supply lines l6 and l7, and the display section DIS is arranged in an easily visible place such as the driver's seat.

In the signal processing unit STS, COD is a coder and constitutes an address output hidden reading circuit, and includes a large number of conducting wires A1 to A11 and B1 to B31 arranged vertically and horizontally.

The vertical conductors A1 to A11 are connected to each output stage of the pinary counter BC, one end of the horizontal conductors B1 to B31 is connected to input terminals #1 to #31 via a diode D, and the other end is connected to a power supply V via a resistor R. .

Commonly connected to 0.

Thirty-one sensors arranged in various parts of the vehicle are connected to these input terminals #1 to #31, respectively.

The intersections of each vertical conductor and horizontal conductor are connected by diodes Da according to the pinary code, as indicated by circles, and these diodes Da are all arranged in a direction that allows current to flow from the horizontal conductor to the vertical conductor.

The OSC is a clock pulse oscillator composed of two NAND gates, and generates a rectangular wave pulse CLK as shown in FIG.

The pulse CLK is the flip-flop F of the pinary counter.
The frequency is divided by F1 to FF4, inverted by inverters 11 to IIO and NAND gate G6, and applied to vertical conductors A1 to A1o.

These vertical conducting wires are arranged in pairs from the left in the drawing to indicate the digits 2, 2, 2, 2, and 2, respectively, with the left line in each group indicating ``1'' and the right line indicating ``0''. ” corresponds to

Since the diode Da is connected as shown in the figure, each terminal #1, #2, etc. is 00001,
oooio... (in the figure, the left and right digits are reversed, with the left being the low-order digit and the right being the high-order digit) and its inverted code.

The rightmost vertical conductor A, 1 is a readout line, and when a part of the sensor is abnormal, a NOR gate 0 is connected to the signal sending circuit via the inverter Ill and the operation test changeover switch SW.
A readout output is applied to one input terminal of each of 1 to G.

The same signal as the address signal applied to the vertical conductor of the coder COD is applied to the other input terminal of these NOR gates.

Therefore, only the address of the abnormal sensor is time-divided from l1 to
It is output to l5.

HDo is a holding circuit consisting of transistors Q1 and Q2, a capacitor C1, a resistor R1, a relay Ry, and a diode D1, and the contact Rya of this relay is inserted into the power supply line l6.

Further, REG is a voltage regulator, which receives a battery voltage Bat of 12 cm, for example, and generates a constant voltage of 5 cm.

Outputs 0.

In the display section DIS, CNT is a control circuit, and N
It is equipped with five sets of two transistors that create l tt , N Q 19, outputs the address signal transmitted through the signal lines l1 to l, and its inverted signal, and outputs the address signal and its inverted signal to the decoder DE.
Add to the vertical conducting wires F1 to F1o of C.

The decoder DEC includes 31 horizontal conductors 01 to G31,
The intersection points of these vertical and horizontal conductors are connected by a diode Da according to a pinary code similar to a coder.

HA is a holding and amplifying circuit, which is similar to the above-mentioned holding circuit H.
Holding circuits HD1 to HD31 having the same configuration as Do are connected to horizontal conductors G.
, -G3, respectively.

The LED is an indicator, in this example a light emitting diode, and is provided corresponding to each sensor.

Further, LP is a common indicator light and is connected between the power supply line 16 and ground.

Next, the operation of this circuit will be explained with reference to the time chart shown in FIG.

The sensors connected to the input terminals #1 to #31 of the signal processing unit STS are normally in the on state and output a ground potential, so each horizontal conductor B1 to B31 is grounded through the diode D, and the output of the inverter 11 is becomes "'1", and Noah gates 01 to G5 are closed.

The oscillator OSC generates a clock pulse CLK, and the pinary counter BC receives this pulse CLK and outputs the coder CO.
1001010101,0 to vertical conducting wires A1 to Alo of D
110010101, 1010010101...
..., that is, the sum of a binary code and its inverted code, is added to each input terminal #1, #2, #3...
・Address.

If there is no abnormality, connect the horizontal conductor B1 of the coder COD as described above.
~B31 is all grounded by each sensor and at low level "L"? Therefore, even if the above-mentioned voltage is applied to each vertical conductor, the output A1 becomes a low level ``L'', and ooooo is sent to the outputs 11 to 1.

When the sensor detects an abnormality, the following happens, namely:
For example, if sensors #3 and #8 detect an abnormality, these sensors will output "1", and as a result, when a voltage of 1010010101 is applied to the vertical conductors A1 to A1o and the #3 terminal is scanned. , all the lines related to the horizontal conducting wire B3 become high level H, and the diode Da becomes non-conductive.

Therefore, the potential of the horizontal conductor B3 increases, which increases the potential of the vertical conductor A1, and the inverter III outputs n O tt
and open Noah Gates 01-G5.

Therefore, the address signal 00011 for the #3 input terminal, which was applied to the other input of these NOR gates, is transmitted to the display section DIS via the signal lines l1 to l.

Further, the "0" output of the inverter (1) is inverted by the inverter I12 and becomes "1", turning on the transistor Q1 of the holding circuit HDo and charging the capacitor C1.

The transistor Q2 remains on for a predetermined period of time until the discharge of the capacitor C1 is completed, energizes the relay Ry, closes the contact Rya, and supplies a voltage of 10 B to the display section.

In the display section DIS, the control circuit CNT receives this address signal and energizes the vertical conductor of the decoder DEC.

When the horizontal conducting wire G3 corresponding to the light emitting diode LED #3 is applied with a voltage of The signal is held for more than 32 times the duration of one address signal, and the #3 light emitting diode is continuously turned on, as well as the lamp Lp indicating that there is an abnormality.

The same goes for the #8 human power terminal, and the #8 light emitting diode L
ED lights up.

In this way, abnormalities detected by the #3 and #8 sensors, such as overheating of the coolant or lack of brake oil, are displayed.

This warning display (lamp Lp and light emitting diode LED
When the abnormality is repaired and the abnormality in the sensor is canceled, the power supply through the signal line 16 is cut off after a certain period of time by the holding circuit HDo that responds to each sensor, and the power supply is canceled.

On the other hand, if all the sensors are normal, the above o
Since the address signal oooo is sent and none of the light emitting diodes emit light, it is possible to know that there is no abnormality.

When the switch SW provided in the signal processing section is switched to the contact b side, the inverter ■tt is disconnected, and one of the inputs of the NOR gate is instead grounded through this switch.

Therefore, if the circuit is normal, NOR gates 01 to G5 are opened, all address signals to terminals #O to #35 are sent out, and all light emitting diodes LED are lit.

In this way, the operation of the device can be tested.

As is clear from the above description, according to the present invention, information regarding a large number of monitoring items can be transmitted in a time-sharing manner using a small number of lines, which greatly contributes to miniaturization of the apparatus.

For signal transmission, the address signal of the sensor that detects the abnormality is sent, and if there is no abnormality, no signal is sent. Therefore, there is no need to add an address to the abnormality warning signal, and the signal format and its The signal circuit becomes extremely simple.

[Brief explanation of drawings]

1 and 2 are together a block diagram showing the structure of a display device according to the present invention, and FIG. 3 is a time chart for explaining the operation. In the drawing, COD is a sensor state reading circuit, G and -G5 are signal sending circuits, STS is a signal processing section, and DIS is a display section.

Claims (1)

[Claims] 1. A signal processing section that includes a circuit that sequentially reads out the output states of sensors arranged in each part of the vehicle according to address signals and a signal sending circuit that sends out the address signal of the sensor that has detected an abnormality as an abnormality warning signal, and a signal processing section that corresponds to each sensor. a display section that includes a display device and operates a display device corresponding to a sensor that receives the address signal and detects an abnormality, and is disposed between the signal processing section and the display section;
When the number of signal lines and a pair of power supply lines sufficient to transmit each bit of the address signal in parallel, and the readout line of the circuit for reading out the output state of the sensor reach the abnormal level, the operation starts and then continues for a certain period of time. is provided corresponding to a first holding circuit that continues to flow a current from the power supply of the signal processing unit side to the display unit side through the power supply line, and each display element of the display unit, and the received address signal disappears. 1. A warning display device for a vehicle, comprising: a second holding circuit that continues to form a path through which current flows from the power supply line to the corresponding display element for a certain period of time even after the power supply line is turned off.