JPH05291927A - Touch switch device - Google Patents

Abstract

PURPOSE:To surely detect an access by a human body even when an area of a touch panel is increased by providing a 2nd resistor to the touch switch device sensing a contact by a person through a change in a potential difference or a static capacitance between the touch panel and a building earth. CONSTITUTION:A primary side of a transformer 12 is connected to an AC commercial power supply 10, a rectified constant voltage device 14 is connected to a secondary side of the transformer 12 and rectifies the input power so that a voltage at one output terminal is always higher than a voltage at the other output terminal by a prescribed voltage. Then, a 1st resistor 18 is provided between a comparison voltage input terminal 20 of a voltage comparator 16 receiving an output voltage of a voltage device 14 as a reference voltage and one output terminal of the voltage device 14. Furthermore, a 2nd resistor 24 is provided between a touch panel 22 connecting to the terminal 20, the other output terminal of the voltage device 14 and a building earth 30. Even when the static capacitance between the touch panel 22 and the building earth 30 is increased due to the increased area of the touch panel 22 by providing the resistor 24, a human contact is surely sensed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch switch device which outputs a switch signal when a person touches it.
More specifically, the present invention relates to a touch switch device suitable for being installed in a toilet room.

[0002]

2. Description of the Related Art Conventionally, a proximity switch is generally used as a cleaning operation switch operated when discharging flush water from a flush toilet. When the user moves his or her hand close to the proximity switch, a cleaning operation signal is output from the proximity switch to the control circuit that controls the discharge of cleaning water. Flush the toilet bowl with flushing water to clean the flush toilet bowl.

However, in this case, not only the toilet user, but for example, even when a cleaning worker enters the toilet booth for cleaning, when the body approaches the proximity switch, the cleaning water is discharged to the flush toilet bowl. There's a problem.

Therefore, by using a touch switch as the cleaning operation switch operated when discharging flush water to the flush toilet, the flush water is discharged to the flush toilet only when the user surely touches the touch switch. It is considered to be.

The conventional touch switch devices include a resistance change detection type and a capacitance change detection type. The former is to detect a decrease in the potential of the switch panel caused by a person touching the switch panel to ground the switch panel. The latter is to detect a change in electrostatic capacitance that similarly occurs when a person touches the switch panel.

[0006]

In the case of the capacitance change detection type, it is necessary to reduce the size of the switch panel in order to increase the rate of change in capacitance caused by human touch, which makes it difficult to operate. was there. That is, when the switch panel is large, the electrostatic capacitance between the switch panel and the ground is large, and therefore the electrostatic capacitance change caused by a human touch becomes relatively small, and the human contact based on the electrostatic capacitance change cannot be detected. Sometimes.

[0007]

A touch switch device according to the present invention includes a transformer whose primary side is connected to an AC commercial power supply,
A rectifying constant voltage device that is connected to the secondary side of the transformer and rectifies so that one output terminal voltage is always higher than the other output terminal voltage by a constant voltage, and an output voltage of the rectifying constant voltage device. And the voltage comparator that is input as the reference voltage,
A first resistor provided between one output terminal of the rectifying constant voltage device and a comparison voltage input terminal of the voltage comparator, a touch plate connected to the comparison voltage input terminal, and the rectifying constant voltage A second resistor provided between the other output terminal of the container and the building earth.

[0008]

When a touch panel of the touch switch device of the present invention is touched by a person, the touch panel is short-circuited with the building ground through the person, thereby changing the potential difference or the capacitance between the touch panel and the building ground, Detects human contact. In this touch switch device, by providing the second resistor, it is possible to reliably detect human contact even if the area of the touch plate is increased and the electrostatic capacitance between the touch plate and the building ground is increased.

[0009]

EXAMPLES Examples will be described below with reference to the drawings.

FIG. 1 is a circuit diagram of a touch switch device according to an embodiment, and FIG. 2 is a perspective view of a toilet room equipped with a toilet bowl cleaning system adopting the touch switch device of FIG. Note that FIG. 3 is a circuit diagram according to a comparative reference example of the circuit of FIG.

In FIG. 2, a toilet booth 1 is provided with a counter 3 composed of a top plate 2A, a front plate 2B, etc.
A flush toilet 4 is installed in front of the counter 3. A toilet user 5 sits on the flush toilet 4 in a sitting state, and after the toilet, a hand 5 is placed on a touch plate 22 formed of a metal material of a cleaning operation switch 7 embedded in a wall surface 6.
It shows a state in which A is being contacted and the flush toilet 4 is about to discharge flush water.

The cleaning operation switch 7 is a touch switch device, and the hand 5A touches the touch plate 2 of the cleaning operation switch 7.
2, when the touch plate 22 touches the hand 2,
As a result of being grounded via the body 5B and legs 5C,
A voltage drop or a capacitance change occurs, and an operation signal is output from the determination circuit.

In this way, when the operation signal output from the cleaning operation switch 7 is input to the flush valve controller (not shown), the flush valve controller controls the opening of the flush valve to flush the flush toilet 4 with flush water. Is discharged.

The structure of this touch switch device will be described below with reference to FIG.

This touch switch device has a transformer 12 whose primary side is connected to an AC commercial power source 10, and the transformer 12
Connected to the secondary side of the rectifier constant voltage device 14 for rectifying so that one output terminal voltage is always higher than the other output terminal voltage by a constant voltage, and the output voltage of the rectification constant voltage device 14 is Voltage comparator 16 input as reference voltage
And a first resistor 18 provided between one output terminal 14a of the rectification constant-voltage regulator 14 and the comparison voltage input terminal 20 of the voltage comparator 16, and connected to the comparison voltage input terminal 20. The touch plate 22, the second output terminal 14b of the rectifier / voltage regulator 14, and the second terminal provided between the building ground 30
And a resistor 24 of.

In the present embodiment, a recovery time adjusting capacitor 26 is provided in parallel with the first resistor 18, and between the comparison voltage input terminal 20 of the voltage comparator 16 and the output terminal 14b of the rectifying constant voltage regulator 14. Is provided with a sensitivity adjusting capacitor 28.

FIG. 3 is a circuit shown as a reference example for convenience of explanation, and differs from the circuit of FIG. 1 only in that the second resistor 24 is omitted.

Next, the operation of the touch switch device will be described.

With reference to the potential of the ground terminal 11 of the commercial power source 10, the voltage on the non-grounded side A on the primary side of the transformer 12 is as shown in FIG.

The transformer 12 receives D from both input and output.
When the C component is not added, the intermediate voltage between the terminals 11 and A becomes the intermediate voltage between B and C. Here, the second resistor 2
Considering the circuit of FIG.
The potential on the non-grounded side of the secondary side of 2 with respect to the grounded side, that is, the voltage of C with respect to B is as shown in FIG.

Looking at B and C from the ground terminal 11 of the commercial power source 11, the voltages of these B and C are as shown in FIG.

The terminal output voltage D of the rectifier-voltage regulator 14 is a voltage higher than B by a constant voltage (for example, 5 V), and the voltage of D is as shown in FIG.

The voltage E of the comparison voltage input terminal 20 of the voltage comparator 16 is D because the capacitance (capacitor 32 virtually indicated by a two-dot chain line) exists between the touch plate 22 and the building ground 30. In comparison, the AC component flows through the capacity 32 to the building ground 30 and decreases, as shown in FIG. Therefore, looking from B to E, the potential of E becomes as shown in FIG.

When a person touches the touch plate 22, the terminal 11, the building ground 30, and the person are alternately grounded when viewed from the commercial power supply ground terminal 11, and the tenth when viewed from B to E. As shown in the figure.

When the voltage indicated by F in FIG. 10 is used as a reference voltage for the voltage comparator 16, the voltage comparator 16 outputs a comparison output during a period G in which E is lower than F, and a person touches the touch plate 22. Can be detected.

However, when the touch plate 22 is increased in size so that it can be easily used, the capacitance 32 increases even when a person is not touching the touch plate 22. The voltage is as shown. Then, when E is viewed from B in this state, it becomes as shown in FIG. 12, and E and F cross each other.

In FIG. 12, H where E is less than F
In the period, the comparison output is output even though the person is not touching the touch plate 22.

Therefore, consider the case where the second resistor 24 is provided as shown in FIG. In the circuit of FIG. 1, the second
By providing the resistor 24 of B, the voltage of B is brought close to the building ground 30. Then, commercial power supply ground terminal 1
The potentials of E, D, and B viewed from 1 are low as shown in FIG. When B and E and F are viewed, it becomes as shown in FIG. 14, and E and F do not cross.

That is, the swing of B becomes small, and thus the swing of D at a constant high voltage becomes small, and the swing of E also decreases. As a result, when B to E are viewed, the touch plate 22 can be returned to the state before being enlarged. Naturally this first
When a person touches the touch plate 22 in the circuit shown in the figure, the potential becomes as shown in FIG. 15, and when B to E are seen, the potential becomes as shown in FIG.

By crossing E and F as shown in FIG. 16, it is possible to detect that a person touches the touch plate 22. That is, by providing the second resistor 24 and selecting the value of the second resistor 24 in accordance with the size of the touch plate 22, it is possible to clearly distinguish when the person touches and when the person does not touch.

[0031]

As is apparent from the above description, the touch switch device of the present invention can reliably detect human contact even if the area of the touch plate is increased. Therefore, the touch switch device of the present invention has an excellent effect that it is easy to find and easy to operate.

The touch switch device of the present invention is relatively
The circuit configuration is simple and inexpensive. It is also resistant to power noise and static electricity.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a touch switch device according to an embodiment.

FIG. 2 is a perspective view of a toilet room.

FIG. 3 is a circuit diagram of a touch switch device according to a comparative reference example.

FIG. 4 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 5 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 6 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 7 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 8 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 9 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 10 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 11 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 12 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 13 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 14 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 15 is a voltage waveform diagram illustrating the operation of the touch switch device.

FIG. 16 is a voltage waveform diagram illustrating the operation of the touch switch device.

[Explanation of symbols]

 10 Commercial Power Supply 12 Transformer 14 Rectifier Constant Voltage Device 16 Voltage Comparator 18, 24 Resistance 22 Touch Plate

Claims (1)

[Claims] 1. A transformer whose primary side is connected to an AC commercial power source and which is connected to a secondary side of the transformer, one output terminal voltage of which is always higher than the other output terminal voltage by a constant voltage. A rectifying constant voltage device for rectifying so that a voltage comparator to which an output voltage of the rectifying constant voltage device is input as a reference voltage, one output terminal of the rectifying constant voltage device and a comparison voltage of the voltage comparator A first resistor provided between the input terminal, a touch plate connected to the comparison voltage input terminal, and a second resistor provided between the other output terminal of the rectifier and voltage regulator and the building ground. And a touch switch device comprising: