JP2585673B2 - Power supply circuit in water supply control device for flusher - Google Patents

Description

The present invention relates to a power supply circuit in a water supply control device for a flusher such as a toilet.

(B) Conventional technology Conventionally, in a water supply control device that automatically controls water supply to a flusher such as a toilet based on detection of use of the flusher by a sensing unit, a system using a photoelectric sensor and an electromagnetic valve has been proposed. Power consumption is large, and the power supply device cannot be downsized.

On the other hand, as disclosed in Japanese Patent Application Laid-Open No. Sho 62-15446, "a washing unit, a sensing unit for sensing use of the washing unit, and a control unit for sending an open / close signal to a water supply unit based on a sensing signal from the sensing unit. And a water supply unit that opens and closes a valve in response to an open / close signal from the control unit. In the water supply control device using a battery as a driving power source, the sensing unit is configured by an infrared sensor having a light emitting element and a light receiving element. Water supply control characterized in that the infrared light emitted from the optical element is intermittently emitted at a predetermined cycle and the light emission cycle when sensing a human body is shorter than the light emission cycle when no human body is sensed. The present invention discloses that the infrared projection from the light emitting element is intermittent, and the cycle of the projection is short when a human body is sensed.
When sensing is not performed, the power consumption is reduced by extending the battery life to extend the life of the battery. However, although the frequency of battery replacement is reduced, the need for battery replacement still remains.

Therefore, it has been considered that a commercial power supply for home use is stepped down to the same voltage as that of the battery by a transformer, and the control device is driven via a rectifier.

(C) Problems to be Solved by the Invention However, the power consumption of the above control device is 6 V and 0.3 mA in the monitoring state in which only the light emitting element, the light receiving element and the control circuit are operated. Nevertheless, when the solenoid of the solenoid valve is driven, there is a peak in power consumption at which 400 mA consumes 12.5 msec of power, and there is a drawback that the power supply device is also increased in size according to this large power.

Accordingly, an object of the present invention is to provide a power supply circuit in a water supply control device for a flusher, which can reduce a capacity and a size by covering an instantaneous load with electric charge accumulated in a capacitor. .

(D) Means for Solving the Problems According to the present invention, in a power supply circuit of a water supply control device for a water washing machine, power is supplied from an AC power supply to a control device via a transformer, a rectifier, and a step-down regulator. The present invention provides a power supply circuit in a water supply control device for a water washer, wherein the input terminal of the regulator and the ground are connected via a capacitor.

(E) Function / Effect According to the present invention, when there is no control output from the control device to the solenoid or the like, the electric charge saturated with the output voltage from the rectifier is accumulated in the capacitor, and the above-mentioned control output is generated. As the input terminal voltage of the regulator drops, the charge is released toward the regulator,
Since the control output is as short as about 12.5 msec as described above, the control output can be covered by the energy of the discharged charges.

Therefore, the transformer and the rectifier in the preceding stage of the regulator can be reduced in capacity, and in particular, the outer type and the heavy transformer can be reduced in size, so that the entire power supply circuit can be reduced in size and weight. .

(F) Embodiment An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a circuit diagram of a power supply circuit (A) according to the present invention, and a plug (1) is provided with an AC power supply of 100 V, 50 or 60 Hz. Is connected to

In the figure, (2) is a fuse, (3) is a transformer,
The AC voltage is reduced to approximately 20 V by the transformer (3).

A rectifier (4) converts an alternating current from the transformer (3) into a direct current and supplies it to a step-down regulator (5).

Regulator (5) is about 20V from rectifier (4)
DC voltage of about 6V of the power supply voltage required by the controller (B)
And stably supplies it to the control circuit (B).
Either the step-down three-terminal regulator (5a) shown in the equivalent circuit diagram of FIG. 2 or the step-down three-terminal regulator (5b) shown in the equivalent circuit diagram of FIG. 3 may be used. For example, it is preferable to use the regulator (5b) shown in FIG.

In FIGS. 2 and 3, (6) is a Zener diode, and (7) is a diode for keeping the Zener current substantially constant.
FET, (8) is a diode for temperature compensation, (9) is an operational amplifier for controlling the transistor (10), and the regulator (5a) of FIG. 2 is a non-inverting differential amplifier circuit of FIG. The regulator (5b) is used as a Schmitt circuit.

The transistor (10) is also used as a current amplifier in the regulator (5a) of FIG. 2 and as a switching element in the regulator (5b) of FIG.

(R1) and (R2) are resistors for dividing the output voltage of the regulator (5) to obtain a comparison voltage.

In FIG. 3, (11) is a reactance for accumulating current energy, and (12) is a diode for keeping current flowing to the output side even when the output from the transistor (10) is OFF. A fast recovery diode such as a Schottky type is used.

 (13) indicates a smoothing capacitor for removing ripples.

In FIG. 1, (S) is a sensor for detecting whether or not a washing machine is used, that is, for detecting a human body. The output of the sensor (S) is input to the control device (B) and subjected to logical operation processing. It is output to a latching solenoid (14o) (14c) described below.

The solenoids (14o) and (14c) are latching solenoids for opening and closing the water supply valve driven by the device (B). When the solenoids (14o) and (14c) are driven, approximately 400 mA is supplied from the control device (B). , About 12.5msec large power is output instantaneously.

In the power supply circuit (A), in the present invention, the input terminal (IN) of the regulator (5) and the grounded common terminal (COM) are usually connected to a range of a smoothing capacitor provided for the purpose of removing ripples, which is provided after the rectifier. Rectifier (4) connected through a large-capacity capacitor (C) beyond
Approximately 20V of electric charge output from the device is stored.

Note that an electrolytic capacitor can be used as the capacitor (C).

Further, (15) indicates a resistor for controlling charging current to the capacitor (C), and (16) indicates a diode for discharging the capacitor (C) without passing through the resistor (15).
The resistor (15) and the diode (16) can be omitted if the charge and discharge current rating of the capacitor (C) is large.

The embodiment of the present invention is configured as described above, and the sensing unit (S) of the control device (B) detects whether or not the flusher is used, that is, only detects the human body, and the latching solenoid (14o) for opening and closing the water supply valve. The current consumption of the control device (B) in the monitoring state in which (14c) is not driven is about 0.3 mA including the current consumption of the light emitting element and the like of the sensing unit (S). It is supplied to the control device (B) via 5).

In the above monitoring state, the capacitor (C) is connected to the output voltage of the rectifier (4), that is, the regulator (5).
It is charged and saturated with the input voltage of.

Next, when the sensing unit (S) senses the presence or absence of a human body and drives the latching solenoids (14o) (14c), about 400 mA and about 12.5 msec of power are output from the control unit (B) as described above. However, this power is used to discharge the electric charge stored in the capacitor (C) by the regulator (5).
Then, it is converted into the output voltage of the regulator (5) and supplied to the control device (B).

That is, as shown in the graph of FIG. 4, in the monitoring state, the capacitor voltage is about the output voltage of the rectifier (4).
Saturated at 20V. When the solenoid (14o) or (14c) is started to drive, the capacitor voltage drops due to the discharge to the regulator (4). The voltage drop time is about 12.5 msec as described above, Then, recharging of the capacitor (C) immediately starts, and the capacitor voltage rises according to a time constant determined by the resistance (15) and the capacity of the capacitor (C), saturates at about 20 V, and returns to the monitoring state.

As described above, the power for driving the latching solenoids (14o) and (14c) is covered by the discharge of the electric charge accumulated in the capacitor (C), so that the transformer (3) for supplying power to the regulator (5) It is possible to make the capacity of the rectifier (4) very small as compared with the conventional one that is adjusted to the peak of the power consumption. In this embodiment, a capacity of about 5 mA is sufficient even if a large margin is expected. is there.

The output voltage of the regulator (5) can be set by a zener voltage and resistors (R1) and (R2). The capacity of the capacitor (C) is determined by the power required to drive the solenoids (14o) and (14c). The resistance (15) can be obtained from the voltage conversion efficiency of the regulator (5), the resistance (15) can be obtained from the capacity of the capacitor (C), and the expected minimum time of the drive intervals of the solenoids (14o) (14c). (3) and the capacity of the rectifier (4) can be obtained from the above-mentioned respective elements.

As described above, in the present invention, the capacity of the transformer and the rectifier of the power supply circuit can be made very small as compared with the conventional one, and in particular, the capacity of the transformer having a large external shape can be small. The power supply circuit can be downsized.

[Brief description of the drawings]

FIG. 1 is a power supply circuit diagram according to the present invention. 2 and 3 are circuit diagrams of a regulator. FIG. 4 is a graph for explaining the relationship between capacitor voltage and time. (A): Power supply circuit (B): Control device (C): Capacitor (IN): Input terminal (3): Transformer (4): Rectifier (5): Regulator

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-156446 (JP, A) JP-A 63-176170 (JP, U) JP-A 50-5229 (JP, Y1)

Claims (1)

(57) [Claims] 1. A power supply circuit (A) for a water supply control device for a water washer.
, The power is supplied from the AC power supply to the control device (B) via the transformer (3), the rectifier (4), and the step-down regulator (5), and the input terminal (IN) of the regulator (5) is provided. A power supply circuit in a water supply control device for a water washer, wherein the power supply circuit for the water washer is connected between the ground and the ground via a condenser.