JP2543080B2 - Electric device with wireless remote control - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to video equipment such as video tape recorders, televisions, video discs, and stereo compact discs.
The present invention relates to an audio device such as a boombox and an air conditioner such as an air conditioner, a cooler, and an oil fan heater, and an electric device with a wireless remote controller which is controlled by operating a wireless remote controller.

2. Description of the Related Art It is publicly known that a power supply unit of a wireless remote controller is configured by combining a secondary battery and a solar battery that charges the secondary battery. Wireless remote control drive IC and operating voltage is 2.0V to 3.3V
Therefore, a carbon lithium secondary battery or the like is used as a small-sized secondary battery suitable for this purpose with little self-discharge. As the solar cell, single crystal silicon and amorphous silicon type solar cells are typical and most widely used. Single crystal silicon solar cells have excellent reliability and almost no optical deterioration, but the assembly and processing costs of cutting, bonding, wire bonding, etc. for series connection are high, and they are not well designed, so they are often used for indoor consumer equipment. Has not been done. Compared to this, amorphous silicon solar cells are inferior to single crystal silicon solar cells in terms of reliability such as photodegradation under high illuminance, but using a plasma CVD method on an insulating substrate at a temperature of 250 ° C or less. Since it is a thin film solar cell that can be formed at a temperature, patterning for series connection can be easily performed with a metal mask at low cost. Therefore, this amorphous silicon solar cell is practically used for calculators. This kind of calculator is 1.5V
Since the power consumption is as low as a few μA, the light receiving area of the solar cell can be as small as about 5 cm ² , and the power consumption is secured with the brightness that allows the liquid crystal display to be viewed, so no secondary battery is required. is there.

Problems to be Solved by the Invention However, in the case of the wireless remote controller, about 455 KH
The operating current of 100 μA or more is required in the operating state where the clock signal is generated by the ceramic oscillator of z
200 for each command when the ED is emitted and the transmission signal is sent
Instantaneous power of about 10 to 60 msec is required at ~ 500 mA, and therefore power consumption of about 1.5 mW · h / day is generally required. In this case, it is a combination power source of a solar cell and a secondary cell, but the efficiency of this solar cell is 3% and the room light of 200 lx (0.2 mW / c
m ² equivalent) only to charge the electric power when charging 1.5 mW · h at require solar cell 50 cm ² things area as the charging for 5 hours / day. This is calculated by the following formula.

1.5mW · h ÷ (0.2mW / cm ² × 0.03 × 5 hours / day) = 50cm ² Such a large area solar cell is not practical in terms of cost and design. Although it is possible to use it for quick charging by direct sunlight, there is a problem that amorphous silicon solar cells are prone to photodegradation when exposed to strong direct sunlight, especially those designed for low illumination. Light deterioration tends to be large.

INDUSTRIAL APPLICABILITY According to the present invention, a conventional solar cell for a wireless remote controller has a small area and is charged with irradiation energy from an appropriate light source incorporated in an electric device, so that there is no photodegradation at the time of charging and the design is cost effective. It is also intended to provide an excellent solar cell power source.

Means for Solving the Problems According to the present invention, when a wireless remote controller is housed in a main body of an electric device, most of the photodegradation of an amorphous silicon solar cell is caused by a light source including a fluorescent lamp or an LED built in the electric device. The secondary battery is charged by irradiating visible light (350 nm to 700 nm) with irradiation energy of 1 to 10 mW / cm ² .

Action FIG. 3 is a diagram showing an example of photodegradation (I / I ₀ ) of the amorphous silicon solar cell when the integrated light reception amount W is 400 mW · h / cm ² . The vertical axis represents the deterioration rate I / I ₀ of the output current, and the horizontal axis represents the irradiation energy density P. Here, I ₀ is the output current before light irradiation, I is the output current after light irradiation, and P is mW per cm ² .

In Fig. 3, assuming that the integrated amount of received light, that is, the generated power is constant, in the case of 400 mW · h / cm ² , it is 10 mW / cm ² more than that of AM1 (100 mW / cm ² ) irradiation for 4 hours. Irradiation of visible light with similar spectral characteristics for 40 hours is the rate of change in output current I / I ₀
Is much less. Therefore, by keeping the irradiation of visible light with an energy of 10 mW / cm ² as the upper limit, the concern of photodegradation can be practically ignored.

The area of a solar cell that is suitable for cost and design is 10 cm.
It is about ² . If the efficiency is 3%, the light of 10 mW / cm ² is 0.5
If you apply it for a while, you can get 1.5mW · h of electricity. This is calculated by the following formula.

1.5mW ・ h ÷ (10mW / cm ² × 0.03 × 10cm ² ) ＝ 0.5 hours The lower limit of practical light source strength is considered to be 1mW / cm ² . In this case, an electric power of 1.5 mW · h can be obtained by irradiation for 5 hours.

Example A typical example according to the present invention is shown in FIG. When the wireless remote controller 4 having the amorphous silicon solar cell 3 mounted therein is inserted into the storage portion 2 of the video tape recorder 1 and stored, the push-in switch 5 is pressed, and the light source 6 such as a white fluorescent lamp or an LED array 6 is pressed. Lights up and the amorphous silicon solar cell 3 facing the light source 6 is illuminated with visible light of 10 mW / cm ² .

When using a white fluorescent lamp as the light source 6, the diameter of the straight tube is 15.5φm
By using a 4W white fluorescent lamp with a length of m and a straight tube of 135 mm, and by placing an amorphous silicon solar cell close to the surface of the tube about 10 mm away from the light emitting part, the main spectrum in the visible part can be obtained. It is possible to irradiate with 8 to 10 mW / cm ² (approximately 8,000 lx to 10,000 lx) of light.

Also, when using GaP LEDs with an emission peak at 570 nm as the light source 6, 10 LEDs with power consumption of 2.1 V and 20 mA (42 mW) per LED are arranged as a planar light source, and this LED is 2-4 mm.
By placing the amorphous silicon solar cell close to a distant position, the emission peak wavelength of the LED and the sensitivity peak wavelength of the solar cell can be made to substantially match, and 0.8 to 1 mW / cm ² of light can be irradiated. it can.

An amorphous silicon solar cell is a PiN junction with a thickness of 1 μm or less formed by plasma CVD using SiH ₄ or a mixed gas of SiH ₄ and GeH ₄ as a main raw material gas, and the optical band gap of the i layer is usually Since it is 1.5 to 1.8 eV, it has a spectral sensitivity peak near the wavelength of 560 to 600 nm, and at wavelengths of 350 nm or less or 700 nm or more, the spectral sensitivity drops to 1/3 or less of the peak value. Therefore, as the light source 6, a visible light source having a main light emitting portion at 350 nm to 700 nm is used.

FIG. 2 is a perspective view of the wireless remote controller 4, and the keyboard 7 and the amorphous silicon solar cell 3 having a relatively small area of about 10 cm ² can be arranged in a well-balanced design. Since the button type carbon lithium secondary battery 8 fixed inside is used in the range of 2V to 3V, the amorphous silicon solar cells 3 are connected in series of 5 to 7 cells. When 6 cells are connected in series with an external area of 10 cm ² , the effective power generation area per cell is approximately 1.2 cm ² (total 1.2 ×
6 = 7.2 cm ² ) can be designed. So 10mW / cm ²
By irradiating with the light of the white fluorescent lamp, a carbon lithium secondary battery with an electric capacity of 1.3 mAh at 2 V can be charged in 1.2 hours. This is calculated by the following formula.

2V × 1.3mAh ÷ (10mW / cm ² × 0.03 × 7.2cm ² ) = 1.2 hours When the voltage across the rechargeable battery is detected and reaches a specified value, the light source 6 is turned off and unnecessary light is emitted. It can be used as a display function of charging completion while preventing deterioration.

EFFECTS OF THE INVENTION As described above, according to the present invention, even in a wireless remote controller that consumes a large amount of power, it is possible to secure practical performance with an amorphous silicon solar cell having a small area, and it is excellent in terms of cost and design. The effect that a small-sized solar cell power supply can be provided can be obtained.

[Brief description of drawings]

FIG. 1 is a structural cross-sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view of a wireless remote controller used in the embodiment of FIG. 1, and FIG. 3 is irradiation light of photodegradation of an amorphous silicon solar cell. It is a figure which shows intensity dependence. 7 ... keyboard, 8 ... secondary battery, 9 ... light emitting window.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Arita 1006 Kadoma, Kadoma City, Matsushita Electric Industrial Co., Ltd. (72) Inventor, Michio Osawa 1006 Kadoma, Kadoma City, Matsushita Electric Industrial Co., Ltd. (56) References JP-A-58-137365 (JP, A)

Claims (1)

(57) [Claims] 1. In an electric device operated by a wireless remote controller, an amorphous silicon solar cell for charging a secondary battery is used as a power source part of the wireless remote controller, and when the wireless remote controller is housed, it is built in the electric device body. The amorphous silicon solar cell is irradiated with light having an energy of 1 to 10 mW / cm ^{2 by} a light source consisting of a fluorescent lamp or an LED having a main light emitting part at a wavelength of 350 nm to 700 nm, and the secondary battery is charged. An electric device with a wireless remote control characterized by: