JPH0144613Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a control circuit for a sanitary cleaning device that sprays hot water to a private part such as the anus to clean the private part.

Conventionally, this type of sanitary cleaning equipment has been used especially in winter.
An instant heating type heat exchanger is used because it can discharge water at an appropriate temperature for a long time even when the water supply temperature is low, and the next person can use it immediately after use. However, this type of heat exchanger depends on the user's preference. If the amount of water discharged is increased by more than a certain amount, there is a drawback that washing water at an appropriate temperature cannot be supplied.

To overcome this drawback, it is possible to increase the heater capacity of the heat exchanger, but as is well known, in general households, the contract current (for example, 10A, 15A, 20A, etc.)
Based on this, so-called safety breakers are installed for protection.

Therefore, if the heater capacity of the heat exchanger is increased, a current exceeding the contracted current will flow when the device is in use due to the usage status of other household electrical equipment, causing the safety breaker to trip. , Therefore, it is not suitable as a device for general home use.

From this point of view, the selection of the heater capacity of the heat exchanger is naturally subject to restrictions.

However, on the other hand, it is also necessary to heat the wash water discharged from the heat exchanger to a temperature suitable for use in order to obtain a comfortable feeling of use.

Taking these points into consideration, if the heater capacity is selected to the maximum allowable value, the heater conductor resistance value will have a product tolerance so-called variation (for example, ±10%).
If a heat exchanger heater with a conductor resistance value at the upper limit is used, the equipment will be used under the worst conditions in relation to the contracted current in each household and the usage conditions of various household electrical devices. In some cases, there is a problem that the safety breaker may trip.

To solve this problem, it may be possible to equalize the conductor resistance values of the heaters incorporated in the heat exchangers of all devices, but this would require measuring and selecting the conductor resistance values of many heaters one by one. There was a problem in that it required a lot of effort to make the device effective.

The purpose of the present invention is to solve these problems and absorb variations in the resistance value of the heater, thereby making it possible to set the power consumption to the maximum allowable for household wiring.

The basic configuration of the present invention is to adjust and fix the minimum value of the control phase angle of the switching element using a clamp circuit that prevents the output voltage sent from the amplifier circuit from dropping below a certain voltage depending on the capacity of the heater. This prevents a current exceeding a predetermined value from flowing.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In the figure, 1 is a power supply terminal connected to an AC power source (not shown) of AC100V, for example. 2 is heating device K
A heater installed together with a temperature sensor S ₁ inside the
It is connected to the power supply terminal 1 via a switching element 4 consisting of a triax or the like. The heating device K is a water inlet 3a of the cylindrical case 3.
A water supply pipe 5 is connected to and communicates with the water outlet 3b and the heater 2 disposed inside the case 3.
is formed by printing a resistor on the surface of a hollow cylindrical ceramic, coating the ceramic insulating protective layer thereon, and sintering it at high temperature.The heater 2 is installed near the water inlet 3a of the case 3. Water entering from the water inlet 3a passes through the hollow of the ceramic, contacts the surface of the ceramic, and enters the water outlet 3b.
When this water passes over the surface of the ceramic, it is heated by a heater 2 that generates heat due to electricity and is discharged.

Temperature sensor S ₁ is formed by printing a resistor on the surface of ceramic, coating it with a ceramic insulation protective layer, and sintering it at high temperature.
It is arranged at a position close to the water outlet 3b in the case 3 to detect the temperature of water discharged from the water outlet 3b. The temperature sensor _S1 used has a positive characteristic in which the resistance value increases as the temperature increases. Also, in case 3 above,
Even if the water supply is temporarily stopped, a certain amount of water remains in order to prevent so-called "dry boiling" caused by the heater 2, and this remaining water is transferred to the heater 2.
The temperature is detected by the temperature sensor _S1 to prevent overheating, and the opening/closing of the switching element 4 is thereby controlled.

Next, the control device 7 will be explained. Reference numeral 8 denotes a resistance-voltage conversion circuit connected to the temperature sensor _S1 , which converts the change in resistance value detected by the temperature sensor _S1 into a voltage and outputs the voltage. Reference numeral 9 denotes an amplifier circuit into which the output Vin of the resistance-voltage conversion circuit 8 is input, and the other input terminal of the amplifier circuit receives the temperature of the cleaning water jetted from the nozzle 6 (for example, 39
By inputting the output Vref of the reference value setting circuit 10, which sets the output corresponding to (°C) by voltage,
These two inputs are compared, and when both inputs have a relationship of (Vin≦Vref), a signal Vout with an output of zero is sent out.

Reference numeral 11 denotes a clamp circuit to which the output Vout of the amplifier circuit 9 is input, and is adapted to send out an output _V1 according to the capacity of the heater 2.

Reference numeral 12 denotes a zero-cross detection circuit which receives the output of a full-wave rectified waveform from the diode bridge DB ₁ connected between the power supply terminal 1 and sends out a pulse signal at the zero point of the input waveform. Reference numeral 13 is connected to the output terminal of the zero-cross detection circuit 12, and outputs a sawtooth wave V synchronized with the half-wave of the AC power input to the power supply terminal 1, making the output zero by the pulse signal of the zero-cross detection circuit 12. This is a sawtooth wave generation circuit that sends out ₂ . 14 is a comparison circuit connected to the output terminals of the clamp circuit 11 and the sawtooth wave generation circuit 13;
By comparing _V1 and _V2 , an output signal of "H" or "L" level is sent out. Reference numeral 15 denotes a gate drive circuit connected to the output terminal of the comparison circuit 14, and is adapted to send a gate signal to the switching element 4 in response to an input signal from the comparison circuit 14. To further explain with reference to FIG. 2 which embodies this control device 7, the resistance-voltage conversion circuit 8 includes a resistor R ₁ and a temperature sensor S ₁ inserted in series between the constant voltage power supply Vcc and the ground. ₁ and temperature sensor
It is formed with the connection point of _S1 as the output end. The resistance value corresponding to the temperature detected by the temperature sensor _S1 and the voltage-divided output by the resistor _R1 are sent out from the output end as the output Vin of the resistance-voltage conversion circuit 8. The reference value setting circuit 10 has a variable resistor VR ₁ and a resistor R ₂ inserted in series between the constant voltage power supply Vcc and the ground, and the connection point between the variable resistor VR ₁ and the resistor R ₂ is formed as an output terminal. Output Vref
A reference value is set so that the temperature of the cleaning water spouted from the nozzle 6 is a set temperature (for example, 39° C.), and a voltage corresponding to this value is sent out as an output.

The amplifier circuit 9 connects the inverting input terminal of the single power supply operational amplifier OP ₁ to the output terminal of the reference value setting circuit 10 through a resistor R ₃
The non-inverting input terminal is connected to the output terminal of the resistance-voltage conversion circuit 8 via a resistor _R4 , and the resistor is connected to the output terminal of this operational amplifier _OP1 and the inverting input terminal.
Insert R ₅ and R ₆ in series, and ground the connection point of resistors R ₅ and R ₆ via resistor R ₇ to connect to the input Vref.
Compare Vin and compare both input Vref and Vin is Vref≧
When Vin is related, output zero signal, and Vref
<Vin, the difference Vref−Vin is determined by the resistances R ₃ , R ₃ = R ₄ , R ₅ , R ₆ , R ₇ , the amplification degree,
The signal is amplified by several hundred times (for example, several hundred times) and then output.

The clamp circuit 11 connects a variable resistor VR ₂ to the output terminal of the amplifier circuit 9, and connects the output terminal of the variable resistor VR ₂ to the constant voltage power supply Vcc via a resistor R ₈ , so that the output from the amplifier circuit 9 becomes zero. Even if it receives a signal, it sends out an output V ₁ so that the voltage does not go below a certain level.

The zero cross detection circuit 12 connects a transistor _Q1 with a grounded emitter to a constant voltage power supply Vcc through a resistor _R9 .
Connect the collector of and connect a resistor between the base and emitter.
_R11 is inserted, and the anode of the diode _D1 whose cathode is connected to the base is connected to the positive DC output terminal of the diode bridge _DB1 through the resistor _R10 , and the collector of the transistor _Q1 is used as the output terminal. ,
Transistor Q ₁ that turns off at the zero point of the full-wave rectified voltage
A pulse signal is sent out from the output end (collector). Sawtooth wave generation circuit 13
Insert resistors _R13 and _R14 and capacitor _C1 in series between constant voltage power supply Vcc and ground, and connect the above resistor _R13 and
Diode D ₂ with anode connected to the connection point of R ₁₄
The cathode of Q ₂ is a transistor with a grounded emitter.
The collector of the transistor Q ₁ of the zero cross detection circuit ₁₂ is connected to the base of the transistor Q 2 via the resistor R ₁₂ , and the connection point of the resistors R ₁₃ and R ₁₄ is used as the output terminal. When _Q2 is off, capacitor _C1 is a resistor
It is charged through R ₁₃ and R ₁₄ and the voltage at the output terminal rises, and when transistor Q ₂ is turned on, the capacitor
By discharging C ₁ in _the circuit of resistor R ₁₄ - diode D ₂ - collector-emitter of transistor Q ₂ , the voltage at the output terminal quickly drops to zero, and the voltage at the output terminal is reduced to zero.
It is designed to send out a sawtooth-wave output V ₂ that is synchronized with the half-wave of the AC power input. The comparator circuit 14 connects the output terminal of the clamp circuit 11 to the inverting input terminal of the operational amplifier OP ₂ and the output terminal of the sawtooth wave generating circuit 13 to _the non-inverting input terminal. When the output V ₂ of the sawtooth wave generation circuit 13 increases
V ₁ ≦ V ₂ “H” level output signal from operational amplifier OP ₂ , and conversely output from sawtooth wave generation circuit 13
When the output V ₁ of the clamp circuit 11 becomes larger than V ₂ , V ₁ >V ₂ The operational amplifier OP ₂ sends out an output signal of “L” level through the respective resistors R ₁₅ .

The gated ramp circuit 15 is the operational amplifier _OP2
The base of a transistor Q ₃ whose emitter is grounded is connected to the output terminal of the transistor Q ₃ , and the anode of a diode D ₆ whose cathode is connected to the collector of this transistor Q 3 is connected to the switching element 4 through a resistor R ₁₆ .
When the input signal is at the "H" level, the transistor _Q3 is turned on and the switching element 4 is turned on, and when the input signal is at the "L" level, it is turned off. Next, its operation will be explained. First, if we explain the state in which the output Vout of the amplifier circuit 9 is directly connected to the inverting input terminal of the comparison circuit 14 without intervening the clamp circuit 11, water flows into the heating device 3 through the water supply pipe 5. When the power supply terminal 1 is connected to an AC power source in this state, the diode bridge DB ₁ outputs a full-wave rectified waveform. (3rd
Figure DB ₁ output) Temperature sensor in initial state
Since the detected temperature of S ₁ is low, the resistance value is also low, so both inputs of the amplifier circuit 9 have a relationship of Vref>Vin, so the output Vout is zero, and the output signal of the comparison circuit 14 that receives this is “H”. " level, the transistor _Q3 of the gate drive circuit 15 is turned on, thereby turning on the switching element 4, and the heater 2 is energized. The water flowing through the heating device K is thereby heated. This heated water is discharged from the water outlet 3b of the heating device K, and the resistance value of the temperature sensor _S1 that detects this also increases in accordance with the increase in the detected temperature, thereby causing the output of the resistance-voltage conversion circuit 8. Although Vin will also rise, the output Vout of the amplifier circuit 9 remains at zero until the relationship between both inputs Vref and Vin of the amplifier circuit 9 becomes Vref<Vin, so the heater 2 continues to be energized. Then, when the input Vin of the amplifier circuit 9 is larger than Vref and Vref<Vin, the amplifier circuit 9 inputs the difference Vref between the two inputs.
- Send out the output Vout obtained by amplifying Vin with a predetermined amplification degree.

Therefore, the output Vout of the amplifier circuit 9 is between zero and Vcc volts.

On the other hand, the zero-cross detection circuit 12 which receives the full-wave rectified voltage from the diode brittle DB ₁ is turned off while the base input of the transistor Q ₁ is lower than the base-emitter voltage of 0.6V, and transmits a pulse signal from the collector to the power supply terminal 1. (output in Fig. 3, 12), the sawtooth wave generating circuit 13 turns on the transistor Q ₂ when receiving the above pulse signal, and turns on the capacitor C. ₁ is discharged, and during the period when the pulse signal is stopped, transistor Q ₂ is turned off, and capacitor C ₁ is charged by constant voltage power supply Vcc through resistors R ₁₃ and R ₁₄ to synchronize the sawtooth wave output signal with the zero point of the AC power supply. It is generated by doing so. This sawtooth waveform output signal is connected to the collector of transistor _Q2 .
This occurs repeatedly at a level that is higher than the zero level by the emitter saturation voltage and the forward voltage drop of diode D ₂ of 0.6 V (V ₂ at the input of OP ₂ in FIG. 3). Therefore, the output of the sawtooth wave generation circuit 13
The lowest potential of _V2 is 0.6V.

In this case, since the output of the amplifier circuit 9 is between zero and Vcc volts, the comparator circuit 14 also has _V1 between zero and Vcc,
When V ₁ becomes 0.6 V or less, the heater 2 is energized at a control angle of 0 degrees. In this case, the applied current increases for heaters with a large capacity and exceeds the maximum power consumption.

Therefore, the output Vout of the amplifier circuit 9 and the comparison circuit 1
When the clamp circuit 11, that is, the variable resistor VR ₂ and the fixed resistor R ₈ are interposed between the inverting input terminal of the V.sub.4 and the inverting input terminal of the V.sub.4, V ₁ =VR ₂ (Vcc-Vout)/R ₃ +VR ₂ +Vout.

In this case, V ₁ is at its minimum when Vout is zero volts, and if the minimum value of V ₁ is set to V ₁ min, then V ₁ min=Vcc/R ₃ +VR ₂ ×VR ₂ .

Therefore, if you set V ₁ min to a voltage of 0.6V or higher, you can achieve a point where V ₁ > V ₂ .
It is possible to make the minimum value of the control phase angle of the switching element 4 greater than zero degrees, and by adjusting and fixing VR ₂ with respect to R ₈ according to the capacity of the heater, it is possible to prevent current from flowing into the heater in excess of a predetermined value. In other words, it is possible to absorb variations in heater resistance and make the maximum power consumption of all products constant.

Since the present invention has the above configuration, it has the following advantages.

The minimum phase angle is adjusted and fixed according to the resistance value of the heater, so there is no variation in the product, and the maximum power consumption can be kept constant even when fully energized, and the safety breaker installed in each home can be tripped when the device is used. This does not occur at all, and the product can be used with peace of mind and is suitable for equipment used in general homes.

Therefore, cleaning water at an appropriate temperature can be supplied even if the amount of water discharged is increased according to the user's preference.

Since the minimum value of the control phase angle of the switching element is fixed, there is no need to detect the conducting current, and no detection time is required, resulting in a quick response.

Since it is not necessary to make the resistance values of the heaters of all products uniform, the cost can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one implementation of the control circuit of the sanitary cleaning device of the present invention, Fig. 2 is a block diagram showing a more concrete version of the configuration of Fig. 1, and Fig. 3 is a time chart explaining the operation. It is. S ₁ ... temperature sensor, 2 ... heater, 4 ... switching element, 7 ... control device, 8 ... resistance-voltage conversion circuit, 9 ... amplifier circuit, 11 ... clamp circuit, K ... heating device .

Claims (1)

[Scope of utility model registration request] In a sanitary cleaning device that has a heater for heating and a sensor that detects the temperature of hot water, the heater is connected to a power source via a switching element, and the gate of the switching element is connected to the gate of the sensor. A resistor-voltage conversion circuit that outputs the change in resistance as a voltage, an amplifier circuit that sends out a phase control voltage proportional to the output voltage of this conversion circuit, and an output voltage that outputs the output voltage from the amplifier circuit to the heater capacity. Accordingly, a control device is provided with a clamp circuit that prevents the voltage from falling below a certain level, and the clamp circuit adjusts and fixes the minimum value of the control phase angle of the switching element according to the capacity of the heater, thereby reducing the maximum power consumption. A control circuit for a sanitary cleaning device characterized by constant control.