JP2000121651A - Meter control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a meter control device capable of reducing the manufacturing cost of electrical equipment as the whole, by providing a speed warning device. SOLUTION: This meter control device includes a CPU 7 for conducting the control processing according to the program data stored in a ROM, wherein a detection signal from a car speed sensor 13 is input to calculate a deflection angle of a meter or a display value, thereby controlling th drive of the meter. A memory 11 previously stores a preset car speed value for warning. The CPU 7 compares the current car speed value calculated according to a detection signal from the car speed sensor 13 and the preset car speed value in the memory 11 to determine whether the current car speed value become equal to or larger than the preset car speed value. When the current car speed value equal to or larger than the preset car speed value is determined, the CPU 7 operates a warning sound generator 16 to generate a warning sound command signal for generating warning sound and output the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a meter control device for an automobile, and more particularly to a meter control device having a speed alarm function.

[0002]

2. Description of the Related Art In recent years, speedometers,
A combination meter in which a tachometer, a fuel gauge, a water temperature gauge, and the like are integrally assembled has been developed. In this type of meter, a cross coil type meter is usually used for each meter, and a meter control circuit with a built-in CPU is used to control and drive each meter, and a vehicle speed sensor, a fuel level sensor, a water temperature sensor, etc. The control circuit takes in the detection signal sent from
The deflection angle is calculated based on the detection data indicated by the detection signals, and each meter pointer is driven in accordance with the deflection angle.

[0003]

Incidentally, a motor vehicle is usually provided with a speed alarm device for generating an alarm sound when the vehicle speed becomes higher than a predetermined vehicle speed during traveling. This type of speed warning device takes in a vehicle speed signal from a vehicle speed sensor, compares it with a preset vehicle speed value,
When the traveling vehicle speed exceeds the set vehicle speed, it operates to generate an alarm sound.However, for this function only, an alarm circuit is provided, and equipment such as laying wiring to take in signals from the vehicle speed sensor is installed. Therefore, there is a problem that the manufacturing cost of electrical components increases.

[0004] The present invention has been made in view of the above points, and it is an object of the present invention to provide a meter control device which has a speed alarm function and can reduce the manufacturing cost of electrical components as a whole. .

[0005]

In order to achieve the above object, a meter control device according to the present invention includes a microprocessor for performing control processing based on program data stored in a memory, and detects a detection signal from a vehicle speed sensor. Enter
In a meter control device that calculates a deflection angle or a display value of a meter and drives and controls the meter, a storage unit that previously stores a set vehicle speed value for warning, and a current vehicle speed value calculated based on a detection signal from a vehicle speed sensor. A speed determination unit that compares the current vehicle speed value with the set vehicle speed value in the storage unit to determine whether or not the current vehicle speed value is equal to or higher than the set vehicle speed value; An alarm sound command signal generating means for generating an alarm sound command signal for operating the sound generator to generate an alarm sound.

Here, the meter control device may be provided with an alarm selection switch for selecting whether or not to generate a speed alarm.

[0007]

According to the meter control device having the above configuration, the built-in microprocessor inputs a detection signal from the vehicle speed sensor and calculates the deflection angle or the display value of the meter.
The meter is driven and the indicated value is displayed. During traveling, the microprocessor also functions as speed determination means, and sets the vehicle speed value calculated based on the detection signal from the vehicle speed sensor as the current vehicle speed value, and stores the current vehicle speed value and the storage means previously stored in the storage means. A comparison is made with the set vehicle speed value to determine whether or not the current vehicle speed value has become equal to or greater than the set vehicle speed value. When the speed determining means determines the current vehicle speed value equal to or higher than the set vehicle speed value, the microprocessor generates an alarm sound command signal and outputs the signal to the alarm sound generator. Thereby, the alarm sound generator operates to generate an alarm sound.

As described above, since the meter control device itself has a function of calculating the vehicle speed value by taking in the detection signal from the vehicle speed sensor, the set vehicle speed value for alarm is stored in the memory in advance. In addition, the speed judgment means for comparing the current vehicle speed value with the set vehicle speed value and the alarm sound command signal generating means for generating an alarm sound command signal can be realized by a microprocessor, so that an independent alarm circuit is provided separately. As compared with the case where the wiring from the vehicle speed sensor is connected thereto, the number of components of the overall electrical components and the number of assembling work steps can be reduced, and the manufacturing cost can be reduced.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration diagram of the meter control device. The meter main body 1 is configured by integrally disposing a speedometer 4, a tachometer 5, a fuel gauge 3, and a water temperature gauge 6 on a case. For example, a cross-coil meter is used for each meter. The cross-coil instrument determines the deflection angle of the pointer shaft attached to the internal movable magnet, that is, the deflection angle of the meter pointer, by the vector composition of the currents flowing through the two coils wound in an intersecting manner. The sine wave characteristic signal and the cosine wave characteristic signal determined by are provided.

[0010] Speedometer 4, tachometer 5, fuel gauge 3, water temperature gauge 6
Are connected to a driver 12 for driving them, and the driver 12 outputs a sine wave characteristic signal and a cosine wave characteristic signal. Each driver 12 is provided with a D / A converter and an amplifier when each instrument is driven by a direct current, and includes a PWM modulation circuit when driven by a pulse width modulation signal. The meter control circuit 2 is connected to the input side of each driver 12.

The meter control circuit 2 includes a CPU 7, an input / output circuit 8, a ROM 9, and an A / D converter 10.
A memory 11 composed of an ORM or the like is connected. Memory 11
Stores correction data for the deflection angle and the like. The input / output circuit 8 is connected to signal lines from a vehicle speed sensor 13, a fuel level detector, a water temperature detector, and the like. Vehicle speed sensor 13
Outputs a pulse signal with a period proportional to the speed,
The CPU 7 inputs a pulse signal having a cycle proportional to the speed or the number of revolutions from the vehicle speed sensor or the rotation detector, measures the cycle of the signal, and calculates speed data and revolution number data. Voltage signals corresponding to the fuel level or the water temperature are output from the fuel level detector and the water temperature detector, and the measured detection signals are input to the A / D converter 10 and taken into the CPU 7.

Further, an alarm sound generator 16 is connected to the output side of the meter control circuit 2 via a driver 15, and a preset vehicle speed value (for example, 1) for generating an alarm sound is stored in the memory 11 in advance.
05 km / h) is stored. The set vehicle speed value for generating the alarm sound can be set and stored at an arbitrary value when the device is manufactured. On the other hand, an alarm selection switch 14 for selecting whether or not to generate a speed alarm is connected to the input side of the meter control circuit 2.

The CPU 7 executes speed data, rotation speed data, fuel level data,
For the water temperature data, the swing angle of each of the hands of the speedometer 4, the tachometer 5, the fuel gauge 3, and the water temperature gauge 6 is calculated from table data indicating the relationship between the swing angle and the data stored in the ROM 9 in advance. I do. Further, the CPU 7 is configured to compare a vehicle speed acquired during traveling with a preset vehicle speed value, and to generate an alarm sound command signal when the vehicle speed becomes equal to or higher than the preset value.

Next, the operation of the meter control device having the above configuration will be described. The meter main body 1 is mounted on a vehicle together with a meter control circuit 2, and a vehicle speed sensor 13, a fuel level detector,
A signal line such as a water temperature detector is connected to the meter control circuit 2.

During operation of the vehicle, a speed pulse signal, a rotation pulse signal, a fuel level detection signal, and a water temperature detection signal are output from a vehicle speed sensor 13, a rotation detector, a fuel level detector, and a water temperature detector, respectively, to a meter control circuit 2. Is input to CPU
When a pulse signal having a period proportional to the speed or the number of rotations is input from the vehicle speed sensor 13 and the rotation detector, the device 7 measures the period of the signal and calculates speed data and rotation number data.
The fuel level detector, the fuel level detection signal from the water temperature detector, and the water temperature detection signal are input to the A / D converter 10 and converted into digital values, and the fuel level data,
The data is taken into the CPU 7 as water temperature data.

Next, the CPU 7 calculates the speed data,
The rotation speed data, the fuel level data, and the water temperature data are stored in advance in the ROM 9 and table data indicating the relationship between the swing angle and the like. Calculate the deflection angle of each pointer.

The deflection angle data of each meter is output to each driver 12, and each driver 12 outputs a sine wave characteristic signal and a cosine wave characteristic signal corresponding to the deflection angle data. Is supplied to the cross coil of each meter, whereby the internal movable magnet and the pointer shaft rotate, and the pointer operates so as to indicate the meter indicated value based on the swing angle data.

On the other hand, as shown in FIG. 2, when the alarm selection switch 14 is turned on, the CPU 7 executes a speed alarm process. When entering this process, first, in step 100
Then, it is determined whether or not the alarm selection switch 14 is turned on. If the alarm selection switch 14 is off, this process ends.

In step 110, vehicle speed data calculated based on the vehicle speed signal from the vehicle speed sensor 13 is fetched.
In the next step 120, the vehicle speed, that is, the current vehicle speed value is compared with a set vehicle speed value preset in the memory 11.
If the current vehicle speed value is lower than the set vehicle speed, this process ends, and no alarm is issued.

On the other hand, if it is determined in step 120 that the current vehicle speed is equal to or higher than the set vehicle speed, the process proceeds to step 130, where the CPU 7 outputs an alarm sound generation command signal to the driver 15. As a result, the alarm sound generator 16 operates and generates an alarm sound indicating that the vehicle speed has become faster than the set value.

As described above, the alarm sound generator 16 is connected to the meter control circuit 2 and the program data for the speed alarm processing is written in the ROM 9 of the meter control circuit 2 only.
The vehicle can be provided with a speed warning function, and the number of circuit components can be reduced as compared with the case where an independent warning circuit is provided. Further, since the meter control circuit 2 has a function of already inputting the vehicle speed signal from the vehicle speed sensor 13 and calculating the vehicle speed data, the connection of the wiring from the vehicle speed sensor and the arithmetic circuit are unnecessary, and the electrical components are not required. The overall manufacturing cost can be reduced.

In the above embodiment, a combination meter having a plurality of meters has been described. However, if the meter control circuit uses a CPU (microprocessor), one meter is provided. May be
The instrument may be a digital display.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a meter control device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of a speed warning process.

[Explanation of symbols]

 2-meter control circuit 4-speedometer 7-CPU 13-vehicle speed sensor 14-alarm selection switch 16-alarm sound generator

Claims (2)

[Claims] A microprocessor that performs a control process based on program data stored in a memory, receives a detection signal from a vehicle speed sensor, calculates a deflection angle or a display value of a meter, and controls driving of the meter. A meter control device that stores in advance a set vehicle speed value for an alarm; compares a current vehicle speed value calculated based on a detection signal from the vehicle speed sensor with a set vehicle speed value in the storage unit; Speed determining means for determining whether or not the vehicle speed value is equal to or higher than the set vehicle speed value; and when the speed determining means determines a current vehicle speed value equal to or higher than the set vehicle speed value, an alarm sound generator is operated to generate an alarm sound. An alarm sound command signal generating means for generating an alarm sound command signal for generating an alarm sound command signal. 2. The meter control device according to claim 1, further comprising an alarm selection switch for selecting whether or not to generate a speed alarm.