JPS5931118B2 - Vehicle warning display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a warning display device for a vehicle that monitors the condition of each part of a vehicle and warns of any abnormality. Regarding the method for displaying warnings.

2. Description of the Related Art In order to ensure safe operation of vehicles such as automobiles, devices have been developed that monitor the condition of each part of the vehicle and immediately warn of any abnormalities.

By the way, there are quite a lot of parts of the vehicle that need to be monitored, so it is necessary to devise a warning display method.

In other words, for warning displays, it is convenient to distinguish the monitored parts, that is, each part of the display items, by voltage differences, etc. However, since the power source available in vehicles is a storage battery, and the voltage is low, when there are many display items, the mutual voltage difference becomes very small, requiring a highly accurate voltage comparator circuit.

Differential amplifiers are generally used in voltage comparison circuits, and these are highly sensitive and operate stably against power supply voltage fluctuations and temperature changes, but they can be used in cases where strong noise from the ignition system etc. enters, such as in automobiles. stability is not necessarily guaranteed.

The present invention addresses the problem of overloading by arranging sensors into blocks according to a large number of display items, so that the number of sensors in each block is small, and thus the voltage difference between them is large.

Priorities should be assigned to each divided block, and sensors with high urgency should be placed in blocks with high priority, and if there are sensors that have detected an abnormality in the high priority group, they should be displayed. Anomaly detection sensors in low priority blocks are now displayed.

In this way, a high-precision voltage comparison circuit is not required for warning display, there is less malfunction due to noise etc., and stability is high, and furthermore, it is possible to display a warning from an abnormality detection sensor without losing rationality. .

The present invention includes a plurality of sensors arranged in various parts of a vehicle,
a plurality of voltage divider circuits connected to the output of the sensor and generating a voltage having a voltage value pre-assigned to the abnormality detection sensor as the sensor output when an abnormality is detected; and an output terminal of each voltage divider circuit. A changeover switch having a plurality of connected fixed contacts, a movable arm having one end as a common contact and the other end being switched and connected to each fixed contact, a drive means for the movable arm, and a changeover switch connected to the plurality of fixed contacts. , a highest voltage output circuit using a diode that outputs only the highest output voltage, two input terminals are connected to the output terminal of the circuit and the common contact, and the output voltage of the highest voltage output circuit and the movable a comparison circuit that compares arm output voltages and gives a signal to the drive means to operate the drive means while the latter is lower than the former, and a display mechanism that is simultaneously driven is connected to the drive means. In the warning display device, the plurality of sensors are divided into a plurality of blocks having different priorities depending on the degree of urgency, and the highest voltage output circuit is provided for each block, and the highest voltage output circuit of the plurality of highest voltage output circuits is The output terminals are respectively connected to respective input terminals of a priority block determination circuit, and are also commonly connected to one input terminal of the comparison circuit through a reverse current blocking diode, and the priority block determination circuit When the highest voltage output circuit of a block is generating an output voltage, only the output terminal of the highest voltage output circuit of a low priority block is forcibly grounded by a transistor that is turned on by the output voltage. The comparator circuit compares only the output voltage of the highest voltage output circuit of the high-priority block that remains ungrounded depending on the polarity of the diode. , this will be explained in detail.

In FIG. 1, sensors 81 to S1o are installed in the engine system, brake system, electrical system, and other parts of the vehicle, and detect abnormalities such as component failure, wear, and insufficient fluid volume, and issue alarms.

All of these sensors operate as switches that are always on and off when an abnormality occurs.

One end of each of these sensors or switches is all grounded, and the other end is connected to the output of a resistive voltage divider.

The voltage divider is resistors R1 and R11, R2 and R1□...
Consists of Rlo and R2o, all ends are grounded,
The other end is connected to power supply element B.

Power source B is an on-vehicle storage battery, and is normally 12V.

In this example, among the resistors constituting the voltage divider, R1 to RIO are all equal, resistors R1□ to R15 are successively smaller, and resistors R16 to R2o are equal to R16 to R1o.

Therefore, voltages that decrease sequentially are generated at the output terminals P1 to P5 of this voltage divider, and the same voltages as P1 to P5 are generated at the output terminals P6 to PIO, but these do not appear because the sensor is always on.

The voltage dividers R1 and R1□ to R5 and R, , t[1 constitute the voltage divider of block A, and the voltage dividers R6 and R16 to R1o and R2o constitute the voltage divider of the second block B.

In this example, the priority is given to the 4th block over the 2nd block B.
Therefore, the sensors 81 to S5 are installed in the parts of the vehicle where there is a high degree of urgency when displaying a warning.

D1-D5. D6-DIO are connected to sensors S1-S5 . by a resistive voltage divider. These diodes take out a high voltage among the characteristic voltages assigned to S6 to StO, and one end is connected to each of the output terminals P1 to PIO of the voltage divider, and the other end is connected to the conductor 'l'2.

These conducting wires are connected to two input lines of the priority block determination circuit PJ.

Output terminals P1 to PIO of the voltage divider are connected to fixed contacts #1 to #10 of a rotation selection switch R8, respectively, and a sliding MA of this switch is connected to one input terminal of a voltage comparison circuit VC.

The output terminal of the priority block determination circuit PJ is connected to the other input terminal of this voltage comparison circuit VC constituted by a differential amplifier.

R8D is a drive circuit for the rotation selection switch R8, which moves the sliding arm A on the fixed contacts #1 to #10 while there is an input.

In this figure 1, the number of sensors is 10. Although the circuit for the number of blocks is shown as two, of course these numbers can be increased or decreased as appropriate.

FIG. 2 shows a circuit example of the priority block determination circuit PJ and the voltage comparison circuit VC.

In this figure, Qt and Q2 are transistors that constitute the judgment circuit PJ, Q3゜Q4 are transistors that constitute the comparison circuit VC, and D1□ to D16 and R2□ to R28 are diodes and resistors attached to these circuits. .

Next, the operation of this warning display device will be explained. In this device, each of the sensors 81 to SIO is normally closed. Therefore, the output terminals P1 to P1o of the resistor voltage divider are all grounded, and the output voltage is O.

In this state, the transistors Q1 and Q2 of the judgment circuit PJ are both off because there is no input voltage, and +B-
D1. A signal is input to the switch drive circuit R8D through the path, and the sliding arm A of the rotation selection switch R8 is returned to the initial position.
It is stopped at this position.

When a sensor that is in a state of force bending, for example, the third sensor S3 of the first block A, detects an abnormality and turns off, a specific voltage (v3 and ) appears.

This voltage v3 causes a base current to flow through the transistor Q1 of the determination circuit through the path 1l-D1□-R2□, turning it on.

Therefore, the signal sent to the switch drive circuit R8D via the +B-D15 path disappears.

Also, the voltage v3 is applied to the transistor Q2 through the path '1-R23.
Turn on and ground the conductor 12.

Therefore, even if the sensor detects an abnormality in the second block B and outputs voltages to the voltage divider output terminals P6 to PIO, these are all reduced to zero.

Further, the voltage v3 is applied as a control voltage to the base of one transistor Q3 of the differential amplifier through the path 1□-D13''2!'t, and is applied to the base of the other transistor Q4 through the path D16-R28 to the rotary switch R8. sliding arm A
(zero when there is no abnormality) is applied, so this differential amplifier supplies an output based on the differential voltage Vx to the switch drive circuit R8D.

The switch drive circuit receives this voltage Vx and begins to advance the sliding arm A of the rotation selection switch R8 one step at a time, that is, from one fixed contact to the next.

The voltage comparator outputs the differential voltage Vx while sliding arm A is at fixed contacts #1 and #2, but when sliding arm A is at fixed contact #3
When it comes to the top, voltage v3 is applied to the sliding arm, which becomes D1.
6 and R28 to the transistor low 40 base.

As a result, both input voltages of the differential amplifier match, and the output voltage becomes a level close to zero.

At this time, voltage is no longer supplied to the switch drive circuit R8D, and the sliding arm A stops advancing.

Display windows (not shown) corresponding to fixed contacts #1 to #10
For example, by displaying a sensor name and interlocking a pointer with the sliding arm A, a warning can be displayed at this pointer position to indicate the location of an abnormality in the vehicle according to the name of the abnormality detection sensor.

The same applies when another sensor detects an abnormality in the first block A, and the fixed contact #1 to which that sensor is connected,
At any one of #2, #4, and #5, the sliding arm A and therefore the pointer stop, and an alarm is displayed.

If a plurality of sensors in the same block detect an abnormality at the same time, the inner shells of the plurality of sensors will also display a high voltage output due to the action of diodes D1 to D6.

When no abnormality is detected in the first block A, and a certain sensor in the second block B, such as S, detects an abnormality and turns off, a predetermined voltage (say V) appears at fixed contact #9.

This voltage V turns on the transistor Q1 through the path 12-D1□-R2□, and as before, makes the voltage applied to the switch 7 drive circuit R8D through the path +B-81 zero, and also ' 2 D14 It is applied as a control signal to the transistor Q3 of the differential amplifier through the R25 path.

Therefore, sliding arm A starts stepping, and fixed contact #1 with zero voltage
It passes through #8 and reaches fixed contact #9, stopping at the roof tile.

When multiple sensors detect an abnormality in the second block B, the sliding arm A is moved at the terminal to which the highest voltage is applied, as before.
will stop and display that the sensor has detected an abnormality.

As is clear from the above description, according to the present invention, a large number of sensors are divided into a plurality of blocks, and voltages are distributed within the blocks. (If the voltage is divided into two, the potential difference will be doubled in the same voltage range).Therefore, the voltage comparator circuit VC does not need to be highly accurate, and the error difference is also reduced.

In addition, since blocks are created such that items with a high degree of urgency are incorporated into blocks with a high priority, there is no problem with the warning display, and the safety of vehicle operation can be ensured.

[Brief explanation of the drawing]

FIG. 4 is a block diagram showing the configuration of the warning display device of the present invention, and FIG. 2 is a diagram showing the circuit configuration of the combination β shown in FIG. In the drawing, A and B are the first and second blocks, 81 to SIO are sensors, R1 to R2o are voltage dividers, D1 to D1o are highest voltage output circuits, VC is a voltage comparison circuit, and Q2 is a low priority block. Transistor, R, that disables the sensor output
8 is a rotation selection switch, R8D is a rotation selection switch R8
This is the drive circuit.

Claims (1)

[Scope of Claims] 1 A plurality of sensors arranged in each part of a vehicle are connected to the outputs of the sensors, and when an abnormality is detected, a voltage of a voltage value pre-assigned to the abnormality detection sensor is transmitted to the sensor. It has a plurality of voltage dividing circuits to generate output, a plurality of fixed contacts connected to the output ends of each voltage dividing circuit, and a movable arm whose one end is used as a common contact and the other end is switched and connected to each fixed contact. a changeover switch, a driving means for the movable arm, a highest voltage output circuit using a diode connected to the plurality of fixed contacts and outputting only the highest output voltage, and an output terminal of the circuit and the common a comparison circuit having two input terminals connected to the contact, which compares the output voltage of the highest voltage output circuit and the movable arm output potential, and gives a signal to the drive means to operate the drive means while the latter is lower than the former; In the vehicle warning display device, the plurality of sensors are divided into a plurality of blocks having different priorities according to their degrees of urgency, and a display mechanism is connected to the driving means to be driven simultaneously. The highest voltage output circuit is provided for each block, and the output terminals of the plurality of highest voltage output circuits are respectively connected to respective input terminals of the priority block determination circuit, and are connected to the comparison circuit in common through a reverse current blocking diode. When the highest voltage output circuit of a high-priority block is producing an output voltage, the priority block determination circuit detects a low-priority block by using a transistor that is turned on by the output voltage. With a configuration in which only the output terminal of the highest voltage output circuit is forcibly grounded, only the output voltage of the highest voltage output circuit of the high priority block that remains ungrounded due to the polarity of the reverse current blocking diode is connected to the comparator circuit. A warning display device for a vehicle, characterized in that it allows comparison.