JP2009067342A - Instrument for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an instrument for a vehicle capable of generating a stable driving voltage and displaying accurate vehicle information. <P>SOLUTION: This instrument for the vehicle including a display means 3 and a control means 1 controlling the display means 3 in order to display the vehicle information based on information from sensors 6 mounted at the side of the vehicle is provided with a display driving circuit 2 driving the display means 3 based on a control signal from the control means 1, a first driving power supply circuit 4 supplying constant voltages to the control means 1 and the display driving circuit 2, and a second driving power supply circuit 5 supplying constant voltages as a driving power supply for the sensors 6. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicular instrument provided with control means for controlling display means based on information from a sensor mounted on the vehicle side.

As a vehicle instrument for displaying conventional vehicle information, for example, there is one disclosed in Patent Document 1. These vehicle meters are equipped with a battery that can stably supply power, and perform various displays using this power as a drive source. This battery is also used as a drive source in various sensors mounted on the vehicle.
JP 2002-1104056 A

  However, in vehicles where the power source capacity of the battery serving as the drive source is small, or in vehicles where the battery is not mounted using only the power source from the alternator as the drive source, the power supply voltage provided from the drive source is not stable, There is a concern that vehicle instruments and various sensors cannot be driven normally and accurate vehicle information cannot be displayed, which is a problem.

  Therefore, an object of the present invention is to provide a vehicle instrument that can generate a stable drive voltage and display accurate vehicle information.

  The constant current circuit according to the present invention includes a display unit and a control unit that controls the display unit to display vehicle information based on information from a sensor mounted on the vehicle side. A display drive circuit for driving the display means based on a control signal from the control means, and a first drive for supplying a constant voltage to the control means and the display drive circuit A vehicle instrument comprising: a power supply circuit; and a second drive power supply circuit that supplies a constant voltage as a drive power supply for the sensor.

  Further, as described in claim 2, in the vehicle meter according to claim 1, the control means, the first drive power supply circuit, and the second drive power supply circuit are the same circuit board. It is characterized by being mounted on.

  According to a third aspect of the present invention, in the vehicular instrument according to the first aspect, the first and second drive power supply circuits include an emitter-follower circuit using a Zener diode. To do.

  The present invention relates to a vehicle instrument that includes display means for displaying based on information from a sensor mounted on a vehicle side, and controls the display means by a control means. The present invention relates to a vehicle instrument that generates stable drive voltage and provides accurate vehicle information. Can be displayed.

  Embodiments to which the present invention is applied will be described below with reference to the accompanying drawings.

  The vehicle instrument of the present invention mounted on a battery-less two-wheeled vehicle will be described as an example. As shown in FIG. 1, the vehicular instrument includes a control unit 1, a display drive circuit 2, a display unit 3, a first drive power supply circuit 4, and a second drive power supply circuit 5. . The vehicle instrument is connected to various sensors 6 on the vehicle side, an ignition switch, and the like.

  For example, a microcomputer can be applied to the control means 1, and signals such as various sensors 6 and an ignition switch (IG-SW) are input by wiring, and a vehicle signal such as a travel signal or an engine speed signal corresponding to the travel speed of the vehicle is input. These signals and the starting point signal from the ignition switch are input, a control signal is generated according to these signals, and this control signal is output to the display drive circuit 2. The control means 1 stores a CPU for performing arithmetic processing based on various input signals, a readable / rewritable RAM for temporarily storing arithmetic processing results and the like in the CPU, a control program and control data. A storage unit including a ROM, and an input / output interface connected by a bus for exchanging the various signals, control signals, clock signals, and the like.

  The display drive circuit 2 is a circuit that generates and outputs a drive signal for driving the display unit 3 based on a control signal from the control unit 1. The display driving circuit 2 can also be configured by the microcomputer described above.

  The display means 3 is for displaying through the display drive circuit 2 on the basis of a control signal from the control means 1 in a vehicle instrument provided in the instrument panel of the vehicle. For example, a liquid crystal display panel can be applied. . In this case, the display means 3 switches and displays the total accumulated travel distance display, the section travel distance display, the outside temperature of the vehicle, the fuel consumption, and the like by a gauge or a numerical value. The display means 3 includes a pointer that rotates in response to a control signal and an indicator such as a scale or a numerical value that is an instruction target of the pointer, and performs so-called analog instrument display for reading and comparing the measured value. Alternatively, these analog instruments may be displayed on a liquid crystal panel in a pseudo manner.

  As shown in FIG. 2, for example, an emitter-follower circuit can be applied to the first drive power supply circuit 4, and a power supply voltage from an alternator mounted on the vehicle is input via a Zener diode, and the control means 1 and The display driving circuit 2 converts and supplies each voltage to a constant voltage that can be driven. An alternator provided with a power generation motor, an AC-DC converter, or the like can be applied. In addition to this, a battery is connected to supply power voltages from the first and second drive power supply circuits 4 and 4. 5 can also be supplied.

  For example, an emitter-follower circuit similar to the first drive power supply circuit 4 shown in FIG. 2 can be applied to the second drive power supply circuit 5, and the power supply voltage from the alternator mounted on the vehicle is supplied via a Zener diode. Are converted into constant voltages that can be driven by various sensors 6 and supplied. In this case, the second drive power supply circuit 5 is provided for each sensor. The first and second drive power supply circuits 4 and 5 include, for example, an emitter-follower circuit, a Zener diode 7 provided so that the output voltage does not exceed a predetermined value, and a power supply voltage as shown in FIG. Is provided with a capacitor 8 that stabilizes when the power supply is momentarily interrupted.

  The various sensors 6 receive a constant voltage provided from the second drive power supply circuit 5 of the vehicle meter, and output the detection result as a detection signal to the control unit 1 of the vehicle meter. In this case, the various sensors 6 output a detection signal having a voltage that varies depending on the fuel level in the fuel tank, or a traveling speed sensor that outputs a detection signal having a pulse waveform having a different frequency according to the traveling speed of the vehicle. An output fuel sensor (liquid level sensor) or the like can be applied. In addition, the control means 1 can perform various arithmetic processing based on this detection signal, and can display vehicle information correctly. For example, the control means 1 adjusts the frequency of the pulse waveform generated from the travel speed sensor and the potential of the detection signal from the fuel sensor (potential difference between the output voltage value to the fuel sensor and the voltage value of the detection signal from the fuel sensor). Based on this, the measurement amount can be obtained.

  Such a vehicle meter includes display means 3 and control means 1 for controlling the display means 3 so as to display vehicle information based on information (detection signal) from a sensor 6 mounted on the vehicle side. A display driving circuit 2 for driving the display unit 3 based on a control signal from the control unit 1 and a first driving power supply circuit 4 for supplying a constant voltage to the control unit 1 and the display driving circuit 2. And a second drive power supply circuit 5 for supplying a constant voltage as a drive power supply for the sensor 6.

  Therefore, since it is possible to generate and supply a stable driving voltage for normal operation of the vehicle meter and various sensors, the vehicle meter can display accurate vehicle information.

  Further, the control means 1, the first drive power supply circuit 4, and the second drive power supply circuit 5 are mounted on the same circuit board, thereby concentrating the function of generating a stable power supply voltage. Can save space. This is particularly advantageous because each sensor 6 can be miniaturized.

  The first and second drive power supply circuits 4 and 5 are composed of an emitter-follower circuit using a Zener diode, thereby generating a stable drive voltage and accurate vehicle information with a simple circuit configuration. Can be displayed.

  Although the vehicular instrument of the present invention has been described as an example in the configuration of the above-described embodiment, the present invention is not limited to this, and other configurations depart from the gist of the present invention. It goes without saying that various improvements and design changes can be made without departing from the scope.

The block diagram which shows the structure of embodiment of this invention. The figure which shows the 1st, 2nd drive circuit of embodiment same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control means 2 Display drive circuit 3 Display means 4 1st drive power supply circuit 5 2nd drive power supply circuit

Claims (3)

Display means;
Control means for controlling the display means to display vehicle information based on information from a sensor mounted on the vehicle side, and a vehicle meter comprising:
A display drive circuit for driving the display means based on a control signal from the control means;
A first drive power supply circuit for supplying a constant voltage to the control means and the display drive circuit;
A second drive power supply circuit for supplying a constant voltage as a drive power supply for the sensor;
A vehicle instrument comprising:   The vehicle instrument according to claim 1, wherein the control means, the first drive power supply circuit, and the second drive power supply circuit are mounted on the same circuit board.   The vehicular instrument according to claim 1, wherein the first and second drive power supply circuits comprise an emitter-follower circuit using a Zener diode.

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