JPS6352291B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a yagura kotatsu in which the power supply to a heating element provided on the yagura kotatsu main body can be wirelessly controlled by an operation unit provided on a table board.

<Prior art> Conventional Yagura kotatsu, for example, a Yagura kotatsu in which a control circuit that controls the energization of a heating element provided in the main body of the Yagura kotatsu is operated by an operation part provided on a table board, has an operation part on the table board and the above-mentioned Yagura kotatsu. It is constructed by connecting the control circuit of the Gurakotatsu body with a lead wire (cord), so when using the kotatsu futon on the Yagura Kotatsu body, the lead wire gets in the way and the table board cannot be used freely. There was a drawback that it could not be placed in the correct direction.

<Objective> The object of the present invention is to provide a yagura kotatsu which eliminates the above-mentioned drawbacks.

<Example> An example of the tower kotatsu of the present invention will be described below with reference to the drawings.

The Yagura Kotatsu of the present invention is constructed as shown in the drawings, and in FIG.
), and the oscillation frequency changes depending on the voltage of the capacitor 13. The oscillation output of the VCO 1 is generated between an electrode plate 11A provided on the yagura kotatsu main body 11 and an electrode plate 12A provided on the table board 12 placed on the yagura kotatsu main body 11 so as to face the electrode plate 11A. Capacitance generated in (stray capacitance)
It is applied to the variable resonant circuit 10 provided on the table plate 12 through wireless connection via capacitor coupling by _CA. The variable resonant circuit 10 is formed of a capacitor, a coil, etc., and the resonant frequency is varied by varying the capacitance of the capacitor or the inductance of the coil by operating an operating section provided on the table plate 12. This is what I did. The resonance signal of the variable resonance circuit 10 is transmitted to the electrode plate 12B provided on the table board 12 and the tower kotatsu main body 11 facing the electrode plate 12B.
Due to the capacitance (stray capacitance) C _B generated between the electrode plate 11B and the electrode plate 11B, the voltage is connected wirelessly through capacitor coupling and is applied to the detector 2 provided on the tower kotatsu main body 11. An amplifier circuit 3 for amplifying the output signal of the detector 2 is connected to the detector 2 . A detection circuit 4 is connected to the amplifier circuit 3 for detecting the output signal of the amplifier circuit 3 (cutting out high frequencies). The output signal of the detection circuit 4 is compared with the reference voltage V _D in the detection circuit, and the output signal is determined as the reference voltage V _D
If it is lower, a comparison circuit 5 is connected to detect that the variable resonance circuit 10 is in a resonant state. In the comparison circuit 5, when the output signal from the detection circuit 4 is higher than the reference voltage V _D , the output of the comparison circuit 5 becomes high level (power supply voltage), charges the capacitor 13 via the resistor 14, and increases the potential of the capacitor 13. to increase the oscillation frequency of VCO1, and
When the output signal from the detection circuit 4 is lower than the reference voltage V _D , the output of the comparison circuit 5 becomes a low level (earth potential), and the capacitor 13 is discharged via the resistor 14, and the voltage of the capacitor 13 drops, causing the VCO
The oscillation frequency of 1 also decreases. A limiter circuit 6 is connected to the connection point between the resistor 14 and the capacitor 13. The limiter circuit 6 becomes low impedance when the potential of the capacitor 13 rises and the oscillation frequency of the VCO 1 exceeds the variable range of the variable resonant circuit 10, and becomes high impedance when the capacitor 13 is discharged to zero voltage. The voltage of the capacitor 13 is used as a reference voltage for temperature control, and the reference voltage is compared with the output voltage of a temperature detection section (not shown), and the detected temperature inside the Yagura Kotatsu is changed based on the comparison result. A temperature detection circuit 7 is connected. A power control circuit 8 is connected to the temperature detection circuit 7, which controls energization of a load 9 such as a heating element in accordance with the output of the temperature detection circuit 7, and maintains the load 9 at a predetermined temperature.

In addition, in FIG. 2, FIG. 2A is an output waveform diagram of the detection circuit 4 of FIG. 1, FIG. 2B is a voltage waveform diagram of the capacitor 13 of FIG. 1, and FIG. 2C is a comparison of FIG. 5 is an output waveform diagram of circuit 5. FIG.

Next, the operating state of the tower kotatsu of the present invention constructed as described above will be explained.

First, the resonant frequency f _p of the variable resonant circuit 10 of the table board 12 is set to a predetermined value by operating the operating section,
When the set resonance frequency f _p is higher than the oscillation frequency of the VCO 1, the detection output of the detection circuit 4 is as shown in Fig. 2A.
Since the voltage V _c becomes higher than the reference voltage V _D of the comparator circuit 5, the oscillation frequency of the VCO 1 increases, and when the oscillation frequency approaches the resonant frequency f _p , the impedance of the variable resonant circuit 10 increases and the detector 2 The potential of the detector circuit 4 decreases, and the output of the detector circuit 4 also decreases. When the output of the detector circuit 4 becomes lower than the reference voltage V _D , the output of the comparator circuit 5 becomes low level, discharging the capacitor 13 and lowering the oscillation frequency. let When the oscillation frequency decreases, it deviates from the resonant frequency f _p , so the impedance of the variable resonant circuit 11 changes, the potential of the detector 2 increases, the output of the detection circuit 4 also increases, and the output becomes the reference voltage.
When the voltage becomes higher than V _D , the output of the comparator circuit 5 becomes high level, charges the capacitor 13, and
Increase the oscillation frequency of VCO1.

The same operation is repeated below.

As mentioned above, since feedback is applied to the VCO1, the voltage of the capacitor 13 is at the resonant frequency.
The voltage becomes a constant voltage proportional to f _p , and this voltage is used as a reference voltage for temperature control, and the reference voltage is compared with the output of the temperature detection section (not shown) of the temperature detection circuit 7, and the output is determined to be the same. When the voltage is higher than the reference voltage, the temperature detection circuit 7 outputs an output, and this output causes the power control circuit 8 to control the energization of the heating element 9 to keep the temperature inside the yagura kotatsu constant. When the resonant frequency is varied by the variable resonance circuit 10, the constant voltage of the capacitor 13 changes, the reference voltage for temperature control changes, and the output ratio of the temperature detection circuit 7 changes. The energization rate to the heating element 9 to be controlled also changes, and the temperature inside the tower kotatsu is controlled to a temperature corresponding to the resonance frequency varied by the variable resonance circuit 10.

<Effects of the Invention> Since the Yagura Kotatsu of the present invention has the above-described configuration, when the Yagura Kotatsu body is used with a kotatsu futon placed on it, the lead wires do not get in the way and the table board can be moved in any direction. Since only the variable resonant circuit that can be mounted and operated by the operation unit is provided on the table board, the space on the table board for the variable resonant circuit is used for variable resistors, monostable multivibrators, etc. It is extremely small in size compared to the case where a temperature control signal generating means formed by a battery or the like serving as a power source is provided.
Therefore, there is no need to secure a special space for installing the variable resonant circuit, and the variable resonant circuit operated by the operation unit can be easily installed at a desired position on the table board. This eliminates the need for battery maintenance and inspection. Since the variable resonant circuit of the table board and the control circuit of the main body of the kotatsu are connected wirelessly by capacitor coupling, the temperature control signal generated by the temperature control signal generating means of the table board of the electric kotatsu is transmitted to the coil and iron core. Compared to what is transmitted via a medium to the temperature control signal detection means installed in the electric kotatsu frame assembly, the noise generated when controlling the temperature of surrounding equipment such as electric carpet heating equipment that uses the yagura kotatsu. The control circuit for the Yagura Kotatsu body can be controlled more reliably using the operating section on the table board. Moreover, the space required for the table plate for providing the electrode plate for capacitor coupling is small, and the electrode plate can be easily provided at a desired position on the table plate.

Furthermore, conventionally, in order to perform temperature control, the detected temperature was converted into a voltage, and this voltage was used to control the energization of the heating element. By using the output voltage as a reference voltage for temperature control, temperature control can be performed simply by quoting conventional technology, and there is no need to provide a separate special control circuit, ensuring reliable temperature control with a simple configuration. can be controlled.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the tower kotatsu of the present invention, and FIGS. 2A, B, and C are waveform diagrams of various parts of FIG. 1. In the drawing, 9 is a heating element, 10 is a variable resonant circuit, 1
1 indicates the main body of the Yagura Kotatsu, and 12 indicates the table board.

Claims (1)

[Claims] 1. A variable resonant circuit whose resonant frequency changes according to the operation of the operating section is provided on the table board, a voltage controlled oscillation circuit whose oscillation frequency changes according to changes in applied voltage, and an oscillation frequency of the voltage controlled oscillator circuit. By comparing the output voltage of the detection circuit with a reference voltage, it is determined that the resonant frequency of the variable resonance circuit and the oscillation frequency of the voltage controlled oscillation circuit match. a comparison circuit for detecting, and a voltage for adjusting the voltage applied to the voltage control oscillation circuit so that the output of the comparison circuit changes the oscillation frequency of the voltage control oscillation circuit in a direction that matches the resonant frequency of the variable resonance circuit. A control circuit consisting of an application means and a power control means for controlling energization to the heating element according to the voltage of the voltage application means is provided in the main body of the Yagura Kotatsu, and electrode plates are provided on the table board and the main body of the Yagura Kotatsu, respectively. A tower kotatsu characterized in that the control circuit and the variable resonance circuit are capacitor-coupled through the electrode plate.