JP2016112953A - Instrument for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an instrument for a vehicle which supplies power to an external apparatus according to a status of an on-vehicle battery.SOLUTION: An instrument for a vehicle comprises a power supply circuit 7 which supplies power to an external apparatus D on the basis of power supply from an on-vehicle battery B, and control means 5 which determines a voltage of power supply wiring W1 connected to the on-vehicle battery B, and switches a power supply state from the power supply circuit 7 to the external apparatus D. The instrument also comprises a voltage detection circuit 6 which detects the voltage of the power supply wiring W1, and the control means 5 controls the power supply circuit 7 on the basis of a detection signal from the voltage detection circuit 6. By this constitution, power can be supplied to the external apparatus D irrespective of an operation state of a vehicle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicular instrument that displays vehicle information, for example, a vehicular instrument that is driven by a rechargeable battery power source and supplies power to an external device.

  2. Description of the Related Art Conventionally, in-vehicle devices are known that include a USB (Universal Serial Bus) as an interface for connecting various peripheral devices (external devices) (see, for example, Patent Document 1). This USB standard connection cable (USB cable) is equipped with a communication line and a power supply line, and can supply power (power supply) to peripheral devices as well as communication between devices. There is an advantage that it can be unnecessary.

JP 2011-150584 A

  However, when the power supply function of these in-vehicle devices is applied to a vehicle meter connected to the in-vehicle battery, the remaining power of the in-vehicle battery is exhausted or not exhausted by power supply to the external device, but the vehicle is started. There was a risk of taking away the power necessary to do this.

  Accordingly, an object of the present invention is to provide a vehicular instrument that feeds power to an external device in accordance with the situation of an in-vehicle battery, paying attention to the above-described problems.

The vehicle instrument of the present invention is
A power supply circuit that supplies power to an external device based on power supplied from the vehicle battery;
Control means for determining a voltage of a power supply wiring connected to the in-vehicle battery and switching a power supply state from the power supply circuit to the external device based on the determination result.

A voltage detection circuit for detecting a voltage of the power supply wiring;
The control means controls the power supply circuit based on a detection signal from the voltage detection circuit.

  Further, the control means is characterized in that a hysteresis is provided in a voltage threshold value of the in-vehicle battery when the power supply state from the power supply circuit to the external device is switched.

  The control means intermittently performs voltage determination processing based on the detection signal.

In addition, the power supply circuit can step down power from the in-vehicle battery and supply a predetermined voltage to the external device,
A switch circuit for stopping the power supply state based on a control signal from the control means is provided between the power supply wiring and the power supply circuit.

Further, a power supply circuit that generates a predetermined voltage based on power supply from the in-vehicle battery and outputs the predetermined voltage;
Control means for determining a voltage of a power supply wiring connected to the in-vehicle battery and switching whether or not a predetermined voltage from the power supply circuit can be output based on the determination result.

  In addition, an output terminal for outputting a predetermined voltage from the power supply circuit to the outside of the vehicle meter is provided.

  The present invention relates to a vehicle meter that displays vehicle information, and can supply power to an external device in accordance with the state of an on-vehicle battery.

The block diagram which shows the structure of embodiment of this invention. The front view which shows the meter for vehicles in embodiment same as the above. The figure which shows the process sequence of the control means in embodiment same as the above.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment in which a vehicle instrument of the present invention is applied as a composite instrument mounted on a motorcycle will be described with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a configuration according to the present invention. A vehicle meter A includes a display 1, a backlight 2, a light emitting display 3, input means 4, control means 5, and voltage detection. A circuit 6, a power supply circuit 7, a switch circuit 8, and a drive power supply circuit 9 are provided.

  These components are electrically connected via a circuit board, wiring, etc., and are held in a case such as a synthetic resin so that the vehicle user can easily check while driving, in this case, the steering wheel. It is provided near the center.

  As shown in FIG. 2, the display unit 1 is a liquid crystal display panel that forms a display image by switching between transmission and non-transmission, and a pointer-type display that indicates an index unit such as a scale or a numerical value by rotation of a motor as a driving source. Although not shown in the figure when the vehicle is powered on, such as during normal driving, the desired vehicle information such as the vehicle speed, the travel distance, the remaining capacity of the in-vehicle battery, and an alarm is based on the control signal from the control means 5 It is an output means for displaying.

  The backlight 2 can be a light source such as a light emitting diode, and is provided on the opposite side of the display surface of the display 1. In this case, the backlight 2 can be applied with an LED chip element provided on the circuit board, and is configured so that the output luminance can be changed according to a control signal from the control means 5. Note that the backlight 2 may be an edge light system using a light guide, instead of the transmitted illumination. In addition, a diffuser plate or the like is interposed on the back side of the display 1 so that illumination light from the backlight 2 can be applied to the display 1 without any spots.

  Similarly to the backlight 2, the light-emitting display unit 3 can apply a light source using a light-emitting diode that can be switched on / off in the light transmission part of the vehicle meter A by a control signal of the control unit 5. Mounted on the circuit board. The light-emitting display unit 3 is a display unit that indicates an operating state of a theft detection device that performs a theft detection using an immobilizer, and performs blinking display in a predetermined pattern that will be described later when the vehicle is not in a power-on state (operating state). . The power-on state can be determined by the control means 5 based on a state signal from the main switch unit C or a signal from another ECU.

  The input means 4 is a trip switch for switching and displaying the total travel distance or the section travel distance on the output screen of the display 1 or a dimming switch for setting the illumination brightness of the vehicle meter A including the display 1 Can be applied. Further, the input means 4 outputs an operation signal corresponding to the pressing operation of the vehicle user to the control means 5. In addition, the input means 4 can also be configured by connecting to a switch outside the vehicle meter A, for example, a steering switch, via a wiring, in addition to the knob switch provided in the vehicle meter A.

  The control means 5 is provided with a storage unit such as a ROM or a RAM (not shown) used for storing a predetermined program and various data, a storage area at the time of calculation, a CPU for performing arithmetic processing according to the predetermined program, an input / output interface, and the like. A microcomputer can be applied.

  Further, the control means 5 inputs operation signals from the input means 4 and vehicle information based on various sensors of the vehicle via a dedicated communication cable (multiplex communication line), and according to these signals the display 1 and the back A control signal for controlling the light 2 and the light emitting display unit 3 is generated and output. In this case, the vehicle meter A is connected via the power supply wiring W1 for receiving power supply from the in-vehicle battery B and the communication cable W2 enabling communication with the main switch unit C, other ECUs, and the like. Has been.

  The control means 5 includes a normal mode in which a vehicle meter is activated by turning on a main switch (start switch) of a main switch unit C that is separately mounted on the vehicle, and vehicle information such as vehicle speed is displayed on the display 1. A power saving mode is prepared in which the normal display output of the vehicle meter A is stopped and the power saving operation is performed by turning off the main switch.

  The control means 5 operates to prevent theft by prompting the flashing display of the light-emitting display unit 3 indicating that the theft detection device is operating when the vehicle is not in a power-on state (in the power saving mode). Can be controlled.

  The voltage detection circuit 6 is a detection circuit that detects the voltage (potential) of the power supply wiring W 1, and includes a voltage dividing circuit for conversion into an electric signal that can be input by the control means 5. The voltage detection circuit 6 outputs a detection signal based on the voltage of the power supply wiring W1 to the control means 5. Based on this detection signal, the control means 5 determines whether or not a voltage for normally driving the control means 5 is obtained, and a determination for outputting an alarm to the display device 1 indicating the degree of deterioration of the in-vehicle battery B. The remaining capacity of the in-vehicle battery B can be determined, and the detection signal is used for many purposes.

  The power supply circuit 7 is connected to the power supply wiring W1 via the switch circuit 8, and generates and outputs a predetermined voltage for supplying power (power supply) to the external device D using the power of the in-vehicle battery B. An adjustment circuit is included. Further, in this case, the power supply circuit 7 can be configured as a part of a USB (Universal Serial Bus) as an interface for connecting various external devices D.

  This USB standard connection cable (USB cable) is connected via a connector mounted on the circuit board of the vehicle meter A, and includes a communication line and a power supply line W3. The terminal (P) can output power (power supply) to the external device D with a predetermined voltage (5 V) output from the terminal P, and there is an advantage that a dedicated power source can be dispensed with from a peripheral device. As the external device D, for example, power can be supplied to a USB standard device such as a portable terminal such as a personal digital assistant (PDA) or a headset.

  When mounted on a motorcycle, a terminal prepared in a storage space such as a glove box can be wired and connected as an output port of the power supply circuit 7. Further, by communicating with the control means 5 through the communication line, information from the external device D is displayed on the display 1 or vehicle information input by the control means 5 is displayed on the external device D. Can also be used.

  The switch circuit 8 switches whether or not the power supply from the in-vehicle battery B is transmitted to the power supply circuit 7 based on a control signal from the control means 5, and a transistor can be applied. The switch circuit 8 switches the power supply state from the power supply circuit 7 to the external device D by switching the power supply to the power supply circuit 7.

  The drive power supply circuit 9 can use a regulator that generates and outputs drive voltages for electronic components such as the control means 5, the display 1, the backlight 2, and the light emitting display unit 3 using the power from the in-vehicle battery B. In this case, the drive power supply circuit 9 steps down the voltage of about 12V from the vehicle-mounted battery B to a voltage of 5V and outputs it.

  Hereinafter, a processing procedure related to the control of the switch circuit 8 by the control means 5 will be described with reference to FIG.

  The control means 5 performs a state determination process (step S1) for determining whether or not power can be supplied from the power supply circuit 7 to the external device D. In this case, the determination can be made based on the control signal transmitted from the control means 5 to the switch circuit 8, but the determination process can also be performed by providing a circuit for detecting the energization state of the power supply circuit 7 or the switch circuit 8.

  In this state determination process, when the power supply circuit 7 is in a state where power can be supplied from the power supply circuit 7, the control unit 5 determines the voltage associated with the decrease in the remaining capacity of the in-vehicle battery B based on the detection signal from the voltage detection circuit 6. A voltage determination process (step S1) for determining the decrease based on the first threshold value is performed. The control means 5 presets a value that is slightly larger than the value corresponding to the voltage (electric power) required at the start of the vehicle as the first threshold value. In this case, as the first threshold value, a threshold value corresponding to a voltage of 10.5 V that is excessively larger than 10 V that can generally operate various in-vehicle devices is set.

  When the control means 5 determines that the voltage of the power supply wiring W2 is lower than the first threshold value, the control means 5 stops (cuts off) the power supply from the in-vehicle battery B to the power supply circuit 7 in the switch circuit 8. ) Is output to the switch circuit 8 (step S3). Therefore, the power supply circuit 7 is switched from a power supply enabled state to the external device D to a power supply disabled state.

  Further, in the state determination process in step S1, when the power supply circuit 7 cannot supply power to the external device D, the control means 5 determines whether the vehicle-mounted battery B is based on the detection signal from the voltage detection circuit 6. A voltage determination process (step S4) is performed for determining a voltage increase accompanying the increase in capacity based on the second threshold value. The control means 5 presets a value larger than the first threshold value as the second threshold value. In this case, 11 V is set in consideration of a temporary increase in voltage value due to a change in the external environment such as a temperature change.

  When the control means 5 determines that the voltage of the power supply wiring W2 is higher than the second threshold value, the control means 5 starts supplying power to the switch circuit 8 from the in-vehicle battery B to the power supply circuit 7 (energization). ) Is output to the switch circuit 8 (step S5). Accordingly, the power supply circuit 7 is switched from a state in which power supply to the external device D cannot be performed to a state in which power supply is possible.

  Further, the control means 5 has a hysteresis characteristic by setting the first and second threshold values to different values in order to determine whether the power supply state is stopped or returned. As a result, it is possible to prevent the remaining capacity of the in-vehicle battery B from being unexpectedly reduced or to prevent the power supply state from flickering.

  By repeating the processing by the control means 5, it is possible to supply power to the external device D in consideration of the remaining capacity of the in-vehicle battery B, and to supply power even in a power saving mode other than the vehicle operating state (normal mode). Can be in a state.

  Further, in the power saving mode, the control means 5 blinks the light-emitting display unit 3 for preventing theft, so that it shifts from the sleep state to the activated state every predetermined time (for example, every 3 seconds) and emits light after the activation. The display unit 3 is turned on and turned off, and the sleep state is again entered while maintaining the output of the control signal to the switch circuit 8.

  By repeating these operations every predetermined time, the control means 5 performs intermittent operation, and performs the above-described voltage determination processing, power supply state switching, and the like in the operation state for lighting the light-emitting display unit 3. Thus, since power consumption can be suppressed as compared with continuous operation, power consumption of the in-vehicle battery B can be suppressed. Further, by performing the voltage determination process described above in synchronization with the blinking operation of the light emitting display unit 3, it is possible to perform the process without activating the control means 5, so that power is saved. Therefore, the power supply time to the external device D can be lengthened.

  Such a vehicle meter determines the voltage of the power supply circuit 7 that supplies power to the external device D based on the power supply from the in-vehicle battery B, and the power supply wiring W1 that is connected to the in-vehicle battery B. And control means 5 for switching the power supply state from the power supply circuit 7 to the external device D.

  Therefore, since the power supply state (power supply enabled state / power supply disabled state) to the external device D can be switched according to the remaining capacity of the in-vehicle battery B regardless of the state of the main switch, the vehicle is purposely activated. Or an in-vehicle instrument that feeds power to the external device D according to the situation of the vehicle without operating other in-vehicle devices that are not necessary.

  Further, a voltage detection circuit 6 for detecting the voltage of the power supply wiring W1 is provided, and the control means 5 easily controls the power supply circuit 7 based on the detection signal from the voltage detection circuit 6 to easily The remaining capacity can be detected.

  Moreover, the control means 5 can supply power stably by providing a hysteresis characteristic to the voltage threshold value of the in-vehicle battery B when the power supply state from the power supply circuit 7 to the external device D is switched.

  Moreover, the control means 5 can suppress the power consumption of the vehicle-mounted battery B by intermittently performing the voltage determination process based on the detection signal.

  Further, the power supply circuit 7 can step down the power from the in-vehicle battery B and supply a predetermined voltage to the external device D. Based on a control signal from the control means 5, the power supply circuit 7 supplies power to the switch circuit 8 that stops this power supply state. By providing between the main wiring W1 and the power supply circuit 7, the power supply state of the power supply circuit 7 can be switched with a simple configuration regardless of the operating state of the control means 5.

  Further, a predetermined voltage is generated based on the power supply from the in-vehicle battery B, the voltage of the power supply circuit 7 that outputs the predetermined voltage and the power supply wiring W1 connected to the in-vehicle battery B is determined, and based on this determination result Thus, by providing control means for switching whether or not a predetermined voltage can be output from the power supply circuit 7, the same effect as described above can be obtained.

  Further, by providing the power supply terminal P for outputting the predetermined voltage from the power supply circuit 7 to the outside of the vehicle meter A, the predetermined voltage can be easily taken out without opening and closing the case. Moreover, the mounting location of the external device D can be freely set by connecting the cables.

  The vehicle display device of the present invention has been described by way of example in the configuration of the embodiment described above, but the present invention is not limited to this, and the gist of the present invention is also achieved in other configurations. It goes without saying that various improvements and design changes can be made without departing from the scope. In addition, although an example of a vehicle instrument mounted on a motorcycle having a small battery capacity compared to a four-wheeled vehicle has been described as an example, it can also be applied to an electric motorcycle or an electric vehicle using an electric motor as a drive source. It is also possible to input voltage and remaining capacity based on vehicle information from the battery unit, and to switch the power supply state based on this.

  In the above-described embodiment, the USB standard connection has been described as an example. However, for example, only a power cable may be used, and a configuration in which power is supplied using a contactless power supply device is described above. The processing procedure and circuit configuration of the control means 5 can also be applied, and the same effects as those described above can be obtained.

  The present invention relates to a vehicular instrument, and is suitable, for example, as a vehicular instrument that is mounted on a moving body including an automobile, a motorcycle, an agricultural machine, or a construction machine.

DESCRIPTION OF SYMBOLS 1 Display 2 Backlight 3 Light emission display part 4 Input means 5 Control means 6 Voltage detection circuit 7 Power supply circuit 8 Switch circuit 9 Drive power supply circuit A Vehicle meter B Vehicle-mounted battery C Main switch unit D External apparatus P Power supply terminal (output) Terminal)

Claims (7)

A power supply circuit that supplies power to an external device based on power supplied from the vehicle battery;
A vehicle instrument comprising: control means for determining a voltage of a power supply wiring connected to the in-vehicle battery and switching a power supply state from the power supply circuit to the external device based on the determination result. A voltage detection circuit for detecting the voltage of the power supply wiring;
2. The vehicle instrument according to claim 1, wherein the control unit controls the power supply circuit based on a detection signal from the voltage detection circuit.   The vehicle instrument according to claim 1, wherein the control unit provides a hysteresis in a voltage threshold value of the in-vehicle battery when the power supply state from the power supply circuit to the external device is switched.   The vehicular instrument according to claim 1, wherein the control unit intermittently performs a voltage determination process based on the detection signal. The power supply circuit can step down power from the in-vehicle battery and supply a predetermined voltage to the external device,
2. The vehicle meter according to claim 1, further comprising a switch circuit for stopping the power supply state between the power supply wiring and the power supply circuit based on a control signal from the control means. A power supply circuit that generates a predetermined voltage based on power supply from the in-vehicle battery and outputs the predetermined voltage;
A vehicle instrument comprising: control means for determining a voltage of a power supply wiring connected to the in-vehicle battery and switching whether or not a predetermined voltage can be output from the power supply circuit based on the determination result.   The vehicle meter according to claim 6, further comprising an output terminal for outputting a predetermined voltage from the power supply circuit to the outside of the vehicle meter.

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