JPS60107432A - Pre-heat device of electric-optical element - Google Patents

Abstract

PURPOSE:To enable an indicator to perform normal operation at the time of engine starting by previously heating the indicator in which electro-chromic material is used. CONSTITUTION:A pre-heat device comprises a temperature control device 3 for maintaining an electric-optical element at the fixed temperature, a door sensor 2 which detects opening and closing of car doors, and a power feed control device 1 which feeds power to the temperature control device 3 for the fixed time. The temperature control device 3 has a power feed switch 31 which controls connection to a battery 4, and feeds power to each active element through the power feed switch 31, and a heater 33 which heats the electric-optical element becomes capable of receiving power supply. When a knob 2 of a car is operated, a limit switch 21 is turned ON, a condenser C11 is charged, and electric current flows in the temperature control device. Thus, the temperature control device is operated, an optical element is heated to the fixed temperature, thereby erroneous operation of an indicator can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention is a display device using a liquid crystal or electrochromic UI31 disposed in an automobile, or an anti-glare device such as a rear-view mirror at a low temperature. The present invention relates to a preheating device for an electro-optical element, which is a heating device for achieving normal operation of an electro-optical element, and is designed to smoothly operate normally when a car starts.

[Prior art]

2. Description of the Related Art Electro-optical elements that utilize electro-optic effects such as liquid crystal materials and electrochromic materials are used in display panels and anti-glare rearview mirrors of automobiles. However, these electro-optical elements have a characteristic that the response speed decreases in the low tone region. This causes erroneous display and malfunction in low humidity areas. In order to improve these shortcomings, a heater is installed in the electro-optical element to heat the electro-optical element to a temperature range that provides the desired response speed, and the temperature is controlled so that it remains within the appropriate temperature range. There is.

However, conventionally, 'fA degree il control using a heater is performed immediately after starting the car engine, so it takes time for these electro-optical elements to reach the desired temperature, and they do not last for a while after the engine starts. 2 - There was a drawback that it had to be done.

[Purpose of the invention]

Therefore, the present invention has been made to improve the above-mentioned drawbacks, and when the temperature of the electro-optical element is lower than a predetermined value, after detecting the opening/closing operation of a car door and before starting the engine. Pre-heating the electro-optical element for a certain period of time 1 When starting the engine, the optical element is already at a temperature that allows normal operation, so that the vehicle can be started immediately - 1 ~The purpose is to provide equipment.

[Structure of the invention]

That is, the present invention is connected to an in-vehicle battery via a power supply switch, detects the temperature of an electro-optical element, and when the temperature is lower than a reference temperature, supplies power to a heater that heats the electro-optical element, and A temperature control device that keeps the temperature of the element constant, a door sensor that detects the opening/closing operation of a car door, and a signal 8 from the door sensor are input, and after inputting the signal, the concentration control device is operated for a predetermined period of time. car bar
3 - a power supply control device that is connected to a battery and supplies power to the temperature control device; and a preheating device for an electro-optical element.

Here, the electro-optic device refers to an element using materials such as liquid crystal and T leftochromic, and refers to an element whose optical characteristics can be changed electrically.

The above temperature control device detects the temperature of this electro-optical element, compares the detected temperature with a reference temperature, and when the detected temperature is low, it heats the electro-optical element to keep it at a constant temperature. This is a device that has the function of holding. Further, this temperature control device is connected to an on-vehicle battery via a power supply switch. This power supply switch is generally linked to the car's ignition switch. That is, when the power supply switch becomes conductive, power is first supplied to the temperature control device from the battery, and the temperature control device becomes operable.

In conventional temperature control devices, the temperature of the electro-optical element can only be controlled when the power supply switch is turned on.

The door sensor detects the opening/closing operation of a door generally on the driver's side of an automobile. Examples include a limit switch that is linked to the operation of a door handle, a limit switch that is installed on the vehicle body that directly detects the opening and closing operation of the door, and that operates when the door is opened and closed, and an optical switch such as a photocoupler.

The power supply control device inputs the signal from the door sensor, connects the temperature control device to the vehicle battery for a predetermined period of time after inputting the signal, and supplies power to the temperature control device. , has a function of bringing the electro-optical element into a state where it can be heated. Generally, a relay contact is provided in parallel with the power supply switch, and the relay switch can be configured to be in a conductive state for a certain period of time after the door sensor detects an operation related to the open state of the door.

By adopting such a configuration, before the power supply switch, which is the main switch of the concentration control switch, becomes conductive,
The possibility of starting the car is detected in advance from the door opening/closing operations, and before starting the car, power is supplied to the temperature control device for a certain period of time to heat the electro-optical element to a predetermined temperature. can be maintained.

〔Example〕

The present invention will be explained in detail based on specific examples.

FIG. 1 is an electric circuit diagram showing the configuration of a preheating device for an electro-optical element according to a specific embodiment of the present invention. The device of this embodiment mainly consists of a temperature control device M3 for maintaining an electro-optical element at a constant temperature, a door sensor 2 for detecting the opening and closing of a car door, and a temperature control device 3 for a certain period of time. It consists of a power supply control device 1 that supplies power.

The temperature control device 3 includes a power supply switch 31 that controls connection to the vehicle battery 4, and a heater 3 that is supplied with power to each active element via the power supply switch 31 and heats the electro-optical element.
3 is in a state where power supply is possible.

The comparator CP1 is supplied with power from the vehicle battery 4 via the power supply switch 31. Further, a reference voltage V2 divided by -6- by resistors R32 and R33 is input to the non-inverting input terminal. On the other hand, at its inverting input terminal, a
: The divided detection voltage V1 has already been input. A thermistor 32 is a thermistor that detects the temperature of a liquid crystal element, which is an electro-optical element used in an anti-glare rearview mirror, and has negative temperature characteristics. These voltages v
1 and v2 are generated via the power supply switch 31, respectively. Further, a positive feedback resistor R34 is connected to the comparator CPI. This resistor R34 is inserted in order to prevent chattering regarding the energization of the heater 33, and to provide a one-h history characteristic to the operation of the T1 comparator CP1, as is well known. The output voltage V3 of the comparator CP1 is connected to the base of the transistor Tr310 via a resistor R35.

The transistor 1r31 is connected to the excitation coil 34a of the relay 34 via a resistor R36 for limiting the current.
The exciting coil 34a is connected to the positive pole of the on-vehicle valve via the power supply switch 31. On the other hand, the relay contact 34b is connected to the heater 33 and controls the power supply to the heater 33.
Ru.

The power supply control device 1 includes a discharge circuit including a capacitor C11 and a resistor R11, a transistor Tr11, and a relay 11. Transistor 1r11 is an N-channel enhancement MO8FET. capacitor 0
The positive electrode of the relay 11 is connected to the insulated gate of the transistor Tr11, and the drain of the transistor Tr11 is connected to the excitation coil Ila of the relay 11 via a current limiting resistor R12. The resistor R11 is for discharging the charge stored in the capacitor 011, and the capacitor length C1
1 to form a discharge circuit for measuring a predetermined time 81 after inputting the signal from the door hinge.

The door sensor 2 is composed of a limit switch 21 that is linked to the operation of the handle of the vehicle.

Next, the operation of the device of this embodiment will be explained.

First, when the handle of the car is operated, the limit switch 2
1 is turned on. Therefore, the capacitor = 8 = C11 is charged from the vehicle battery 4. Therefore, the transistor Trll is turned on, and the relay contact 11
b is turned on, and the contact a of the temperature control device is connected to the vehicle battery 4.
voltage is induced. Therefore, the temperature control device 3 becomes operational.

On the other hand, when the limit switch 21 is turned off, the electric charge charged in the capacitor C11 is discharged via the resistor R11 at a temperature determined by a time constant. Therefore, the transistor Tr11 is turned off after a certain period of time after being turned on, and similarly the relay contact 11b is also turned off after a certain period of time.

Therefore, the temperature control device 3 is supplied with power for a certain period of time after the door opening operation is detected.

The operation of the temperature control device 3 will be explained next.

When the temperature of the liquid crystal element is lower than the reference temperature, the resistance of the thermistor 32 is high (therefore, the reference voltage V2 is higher than the detection voltage V1. Therefore, the output voltage v3 of the comparator CP1 becomes high level, and the transistor l'- r31
is in the on state. Therefore, the relay contact 34b is turned on, a -9- current is supplied to the heater 33, and the liquid crystal element is heated. At this time, the reference voltage v2 increases because the output voltage v3 is fed back via the feedback resistor R34. Therefore, even if the liquid crystal element is heated and the detected temperature v1 rises, the reference voltage v2 will be
Since it is set somewhat higher than before, current is supplied and the liquid crystal element is heated until it reaches the temperature corresponding to the reference voltage V2 of A. This comparator C
Such circumferential characteristics of P1 prevent chattering in the current supply with respect to temperature fluctuations near the base temperature of the liquid crystal element. As the temperature of the liquid crystal element increases, the resistance R32 of the thermistor becomes smaller, the detected temperature v1 becomes higher than the reference voltage v2, and the output voltage V3 becomes a low level.

Therefore, the transistor king r31 is turned off, the relay contact 34b is turned off, and the current to the heater 33 is cut off.

In this way, the liquid crystal element is controlled so that it always exists within a constant temperature range.

After a predetermined period of time has elapsed since the switch 21 was turned on and the relay contact 11b was turned on, the power supply switch 31 is turned on and the temperature is Power is supplied to the control device 3, and normal temperature control is performed when the vehicle is operated.

By adopting the above configuration, the operation of the handle of the automobile is detected prior to the ON state of the power supply switch 31, and when this is detected, power is supplied to the temperature control device 3 for a predetermined period of time, and the temperature control device 3 into an operable state, and the liquid crystal element can be heated and maintained at a predetermined temperature in advance if necessary.

FIG. 2 is an electric circuit diagram showing the configuration of an electro-optical device according to another embodiment of the present invention. This embodiment is characterized by directly detecting the opening/closing operation of the door. For this purpose, the door sensor 2 is the limit switch 2.
2, a flip-flop circuit 23 (hereinafter referred to as ``circuit'') that prevents the chattering operation of this limit switch 22, and the Q terminal output of the FF circuit 23, and a constant It consists of a pulse generator 24 that outputs pulses with a short pulse width.

-11- When the limit switch 22 is operated and the open state of the door is detected, the F circuit 23 enters the "let" state and its Q terminal output becomes high level.Therefore, the pulse generator 24 synchronizes with the rising edge. That is, the pulse generator 240 signal (5) is a signal that outputs one pulse when a transition of the door from a closed state to an open state is detected.

The power supply control ill device 1 is a monostable multivibrator 12
, transistors R1 to R11 connected to the Q terminal, and a relay 11. (1) The stable multi-bye break 12 inputs the signal from the pulse generator 24 and outputs a high level signal to Trll for a certain period of time. Therefore, Trll can close the relay contact 111 for a certain period of time (in a conductive state) for a predetermined period of time.

The configuration of the temperature control device 3 is the same as in the first embodiment.

In this manner, the present embodiment is characterized in that the open state of the door is detected and the temperature control device 3 is supplied with the signal for a predetermined period of time after the detection. This Second Implementation-12- Example The device is configured for a predetermined period of time after the door is first opened, even if the door is always in the open state.
Since power is supplied to the temperature control device, even if the door is opened for a long time for purposes other than starting the car, power will not be supplied to the temperature control device for a long time, so the battery discharge can be prevented.

(Effects of the Invention) In short, the present invention provides a method for pre-supplying power to a temperature control device that controls the temperature of an electro-optical element so that it always remains within a certain range before operating the main switch. Installing a door sensor υ that detects the opening and closing operations of car doors.
This device is designed to supply power to the furniture control device for a certain period of time when a signal from the door sensor is input. Therefore, since the device of the present invention detects the opening/closing operation of the car door and supplies power for a predetermined period of time, the device supplies power to the heater provided in the electro-optical element prior to starting the car, and generates electricity. It is possible to preheat the optical element to a temperature range that allows normal operation. Therefore, the vehicle can be started quickly. Further, since the signal from the door sensor that detects the opening/closing operation of the door is inputted so that power can be supplied for a certain period of time, it is possible to prevent the battery from discharging by 1F.

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram showing the configuration of a pre-1 apparatus for an electro-optical element according to a specific embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of a preheating device for an electro-optical element according to a second embodiment of the device of the invention. 1...Power supply control device 2...Door sensor 3...Temperature control device 4...Battery 11...Relay 34...Relay CPl...Comparator 14 -

Claims (1)

[Claims] Connected to an on-vehicle valve via a power supply switch,
A temperature control device that detects the temperature of an electro-optical element and, when the temperature is lower than a reference temperature, supplies power to a heater that heats the electro-optical element to keep the temperature of the electro-optical element constant; a door sensor that detects an operation; a signal from the door sensor is input; after inputting the signal, the temperature control device is connected to the vehicle battery for a predetermined time;
A preheating device for an electro-optical element, comprising: a power supply control device that supplies power to the temperature control device;