JPS6364692B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a kotatsu tower in which the power supply to a load such as a heating element disposed on the main body of the kotatsu tower can be wirelessly controlled by an operation unit provided on a table board.

Conventional Yagura Kotatsu, for example, Yagura Kotatsu, in which the control circuit that controls the power supply to the heating element of the Yagura Kotatsu body is operated by an operation part provided on a table board placed on the Yagura Kotatsu body, is operated by an operation section provided on the table board. The control circuit that controls the power supply to the heating element of the main body of the Yagura Kotatsu is connected by a lead wire (cord), and for this purpose, the Kotatsu futon is placed on the main body of the Yagura Kotatsu. In some cases, the lead wires got in the way and the table board could not be placed in any direction.

The present invention relates to a yagura kotatsu that eliminates the above-mentioned drawbacks.

An embodiment 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. In FIG. 1 of the drawings, numeral 1 denotes a voltage controlled oscillator (hereinafter abbreviated as VCO) whose oscillation frequency changes depending on the level of an external voltage. 2A and 2B are electrode plates for transmitting and receiving signals provided on the main body 19 of the Yagura Kotatsu, and 3A and 3B are electrodes for sending and receiving signals that are provided on the table board 20 that is placed on the main body 19 of the Yagura Kotatsu. plate, the above electrode plate 2A
They form a pair facing 2B to 2B. 4 is an inductance, 5 is a capacitance, and the inductance 4 and capacitance 5 constitute a parallel resonator. 6 is a detector for resonant and non-resonant signals, 7 is an amplifier, 8 is a wave detector, and 9 is a comparator, the output of which becomes a low level potential when resonance occurs and a high level potential when non-resonance occurs. 10, 13, and 15 are resistors, 11 is a capacitor, 12 is a PUT (programmable union transistor), and +Vcc is a DC power supply. As shown in FIG. 2, the electric potential (potential) becomes a sawtooth potential shown by a dashed line when there is no resonance, and becomes a DC potential shown as a solid line when it resonates. 1
6 is a detector that detects a signal from a temperature sensor (not shown), and outputs a control signal based on a reference signal consisting of the output potential (anode potential of PUT 12) of the relaxation oscillation circuit consisting of PUT 12 and the like and the signal from the temperature sensor. Reference numeral 17 denotes a control circuit which inputs a control signal for the detector 16 and controls conduction of the load 18 based on the control signal. Furthermore, the output of the relaxation oscillator circuit is not only applied as a reference signal to the detector 16, but also as an external potential of the VCO 1.
It is applied to VCO1 and determines the oscillation frequency of VCO1.

In Figure 2, the sawtooth potential indicated by the dashed line A is the output of the relaxation oscillation circuit during non-resonance (anode potential of PUT12), and when this potential is applied to VCO1, the oscillation frequency of VCO1 corresponds to that potential. and changes from frequency f ₁ to frequency f ₂ (oscillates at frequency f ₂ when the potential is the lowest, and oscillates at frequency f ₁ when the potential is the highest). The DC potential shown by the solid line B in Figure 2 is the output of the relaxation oscillator circuit during resonance, and this potential is
When applied to VCO1, the oscillation frequency oscillates at the oscillation frequency corresponding to the potential, and as described later, the oscillation frequency is maintained at the resonance frequency F ₀ (this resonant frequency f ₀ is determined by the resonator's variable By varying the capacitance 5, a certain range f ₁ ≦
can be determined arbitrarily with f ₀ ≦ f ₂ ).

In Fig. 3, 18 is a load (heating element), 19
The main body of the Hayagura kotatsu, 20, is a table board equipped with a resonant circuit and the like. Reference numeral 21 denotes an operating section provided on the table board 20. By operating a knob (not shown) of the operating section 21, the capacitance of the variable capacitance 5 of the resonator is varied and the resonant frequency is changed. 22 is a kotatsu futon for keeping warm.

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

First, when the output of the comparator 9 is at a high level in a non-resonant state, the PUT 12 undergoes relaxation oscillation, and the output of the comparator 9 becomes a sawtooth potential as shown by the dashed line A in FIG. 2 and is applied to the VCO 1. Therefore, the oscillation frequency is continuously swept from frequency f ₁ to frequency f ₂ . The signal is transmitted between the electrode plate 2A and the electrode plate 3.
Table plate 20 through the stray capacitance C _A between
is applied to the resonator. And the signal is transmitted to the electrode plate 2
The signal from the detector 6 is applied to the detector 6 via the stray capacitance C _B between B and the electrode plate 3B, and the signal from the detector 6 is amplified by the amplifier 7 and applied to the detector 8. and input to the comparator 9.
When a certain resonant frequency f ₀ (f ₁ ≦f ₀ ≦f ₂ ) among the frequencies f ₁ to f ₂ is input to the comparator 9, a low potential signal is not likely to be output (non-resonant). outputs a high potential signal. Then, when the output of comparator 9 becomes a low potential at resonance frequency f ₀ ,
The relaxation oscillation caused by PUT12 etc. stops and the PUT12
The sweep stops at the anode potential at that time, and the oscillation frequency of the VCO 1 also stops at the resonance frequency _f0 at that time. and the above PUT
When the anode potential of the comparator 12 decreases and the potential applied to the VCO 1 also decreases, the oscillation frequency of the VCO 1 also oscillates at a frequency that deviates from the resonant frequency, and the output of the comparator 9 also (deviates from resonance and becomes non-resonant). (because of this), the potential becomes high and the anode potential of PUT 12 also rises, reaching the level of the resonant frequency f ₀ and stopping at that potential. In this way
Anode potential of PUT12 (output of relaxation oscillation circuit)
is maintained at a constant level by repeating resonance and non-resonance. This level changes correspondingly when the resonant frequency f ₀ changes, and the resonant frequency f ₀ changes by varying the capacitance 5. Furthermore, the output of the relaxation oscillator circuit is applied to VCO1 and
Not only is the oscillation frequency of 1 kept at a constant oscillation frequency at the resonant frequency, but it is also applied to the detector 16 as a reference signal for temperature control, as well as a detection signal of the temperature of the load 18 from a temperature sensor (not shown). is applied, the detector 16 compares the reference signal and the detection signal, and based on the comparison result, the detector 16 outputs a control signal, and the control circuit 17 controls the energization to the load 18 based on the control signal. Perform temperature control.

Since the yagura kotatsu of the present invention has the above-described configuration, the lead wires do not get in the way when the kotatsu futon is placed on the yagura kotatsu body and the table board can be placed in any direction. Moreover, since only the resonator operated by the operation unit is installed on the table board, the space for the resonator on the table board can be formed by a variable resistor, a monostable multivibrator, and a battery that powers them, etc. on the table board. It is extremely small compared to the case where a temperature control signal generating means is provided. Therefore, there is no need to secure a special space for installing the resonator, the resonator operated by the operation unit can be easily installed at a desired position on the table board, and the need for a battery as a power source can be eliminated. This eliminates the need for battery maintenance and inspection. Since the resonator 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 transferred to a medium consisting of a coil and an iron core. Compared to the one that transmits the temperature control signal to the temperature control signal detection means installed on the electric kotatsu frame base, it is more susceptible to noise generated when controlling the temperature of surrounding equipment such as electric carpet heating equipment. Therefore, the control circuit of the yagura kotatsu body can be more reliably controlled by 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, since the control signal of the operating section is transmitted at the resonant frequency, the influence of external noise is much smaller than when the control signal is transmitted at a mere oscillation frequency, and accurate control can be performed.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the circuit configuration of one embodiment of the tower kotatsu of the present invention, and Fig. 2 is the same as Fig. 1.
An output waveform diagram of the relaxation oscillation circuit by PUT, and FIG. 3 is a cross-sectional configuration diagram of the main part of an embodiment of the tower kotatsu of the present invention. In the drawing, 1 is a voltage controlled oscillator, 14 is a load, 1
9 is the Yagura Kotatsu body, 20 is the table board, 21
indicates the operation section.

Claims (1)

[Claims] 1. A voltage-controlled oscillator whose oscillation frequency changes according to changes in applied voltage, including a resonator whose resonance frequency changes according to the operation of the operating section, and a resonant state of the oscillation frequency of the voltage-controlled oscillator. a relaxation circuit that applies a voltage to the voltage controlled oscillator so that the output of the detector changes the oscillation frequency of the voltage controlled oscillator in a direction that coincides with the resonant frequency; A control circuit consisting of a power control means for controlling energization to the heating element according to the output is provided on 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, and the electrode plates connect the resonator and the above. A yagura kotatsu characterized by a control circuit coupled with a capacitor.