JPH06102362A - Object detecting method - Google Patents

Abstract

PURPOSE:To reduce the current consumption and prolong the life of a light emitting element by detecting the ambient light in the detection region, comparing the ambient light level or its fluctuation width with the preset value, and controlling the light projection quantity of the light emitting element. CONSTITUTION:The ambient light level is detected, and whether this level is within the preset range or not is judged in the control program that light is emitted from a light emitting element and the light reflected on an object is received to detect the object. When this level is higher (lower) than the preset range, the light projection quantity of the light emitting element is increased (decreased). When this level is kept within the preset range, the light projection quantity is left as it is, then the fluctuation width of the level is judged. When the fluctuation width is larger (smaller) than the preset range, the light projection quantity is increased (decreased). When the fluctuation width is kept within the preset range, the light projection quantity is left as it is. When this interruption program is executed, the object can be detected with high precision, the current consumption is reduced, and the life of the light emitting element can be prolonged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object detecting method suitable for application to an automatic water supply controller, an automatic hot air controller such as a hand dryer, and the like.

[0002]

2. Description of the Related Art An automatic water supply control device for automatically supplying water when a hand is put out below a spout of a faucet, or an automatic temperature control device where hot air is automatically blown out when a hand is put out below a hand dryer. Wind control devices are widely used. FIG. 2 shows a schematic block diagram of this type of automatic water supply control device and automatic hot air control device.

This controller is a microcomputer 1.
The light emitting element 14 is actuated by a signal from the microcomputer 10 via the light projecting circuit 12 to project light. The light reflected by the object to be detected is received by the light receiving element 16, the received light signal is amplified by the amplifier 18, and then only the signal in the predetermined frequency band is taken out by the filter 20 and the A / D converter 22. Converted to a digital signal, the microcomputer 10
Entered in. A control signal from the microcomputer 10 activates the drive circuit 24 for the water supply mechanism and the warm air mechanism.

FIG. 4 is a schematic diagram of an automatic faucet 28 incorporating the automatic water supply control device 26. Faucet 30
A light-receiving element 16 and a light-emitting element 14 are installed at the tip of the, and this detection signal is input to the control device 26. A solenoid valve 34 is provided in the middle of the water supply pipe 32 connected to the faucet fitting 30.
Is provided, and the solenoid valve 34 is
It is opened and closed by the signal from.

FIG. 5 is a sectional view of an automatic hand dryer 36 incorporating an automatic warm air controller, and a casing 38.
A fan 40 and an air heater 42 are installed inside.
The light receiving element 16 and the light emitting element 14 are provided under the casing 38.
Is installed, and its detection signal is the automatic warm air control device 4
4 and the signal from the controller 44 operates the fan 40 and the heater 42.

For example, as shown in FIG.
When the human body is detected by 6, the electromagnetic valve 34 is opened, and the fan 40 and the heater 42 are operated. When the human body is no longer detected, it is stopped (the valve is closed and the fan and the heater are stopped).

Note that an automatic flush toilet including a similar water supply control system is also widely used. In the case of an automatic cleaning urinal, for example, when a human body is detected, first, cleaning water is supplied to the toilet for a predetermined time, and then, when the human body leaves, a large amount of cleaning water is supplied.

[0008]

When the ambient light level is extremely high or when the ambient light level fluctuates greatly, the object detection signal detected by the light receiving element 16 is hidden by the ambient light level, and There are cases where the detection accuracy is reduced or it becomes impossible to detect an object. As a measure against this,
Although it is possible to always increase the amount of light emitted from the light emitting element, the current consumption increases, which not only causes great inconvenience in a device using a battery as a driving power source, but also shortens the life of the light emitting element. There is a drawback that.

[0009]

An object detecting method of the present invention is a method of projecting light from a light emitting element and detecting reflected light of this light by a light receiving element to detect an object. The level is detected, and when the ambient light level is lower than a predetermined value, or when the fluctuation of the ambient light level is smaller than a predetermined value, the amount of light emitted from the light emitting element is reduced so that the ambient light level is lower than the predetermined value. Is also large,
Alternatively, when the fluctuation of the ambient light level is larger than a predetermined value, the amount of light projected from the light emitting element is increased.

[0010]

According to the object detecting method of the present invention, the amount of light emitted from the light emitting element is small when the ambient light level is low or when the fluctuation of the ambient light level is small. On the contrary, when the ambient light level is high or when the ambient light level fluctuates greatly, the amount of light emitted from the light emitting element is increased. As a result, the amount of light projected is increased only when necessary, and reliable object detection is performed, and the amount of light projected is reduced when unnecessary, so that current consumption can be suppressed and the life of the light emitting element can be extended.

[0011]

Embodiments will be described below with reference to the drawings. FIG. 1 is a flow chart showing an example of a control program adopted in the method of the present invention. That is, in the present invention, basically, similar to that shown in FIGS. 2 and 3, the light emitted by the light emitting element and reflected by the object is received by the light receiving element to detect the object. Then, in response to the detection of this object, water supply, water stoppage, hot air supply, or hot air stop is performed. In this control program,
The interrupt program shown in FIG. 1 is appropriately executed. In FIG. 1, the ambient light level is first detected,
It is determined whether this level is within a predetermined range. When the ambient light level is higher than the predetermined range, the light projection amount is increased. Further, when the ambient light level is below the predetermined range, the light projection amount is reduced. When the ambient light level is within the predetermined range, the light projection amount is kept as it is, and then the fluctuation range of the ambient light level is judged. When the fluctuation range is larger than the predetermined range, the light projection amount is similarly increased, and when it is smaller than the predetermined range, the light projection amount is reduced. When the fluctuation range is within the predetermined range, the light projection amount is left unchanged.

By executing such an interrupt program, the light projection amount is adjusted according to the ambient light level,
Enables highly accurate object detection. Further, when the amount of projected light is small, the amount of projected light is reduced, so that the current consumption can be reduced and the life of the light emitting element can be extended.

The method of the present invention can be applied not only to an apparatus for detecting a human body such as an automatic toilet bowl, an automatic water faucet, an automatic hand dryer, etc., but also to an apparatus for detecting articles in a factory or the like.

[0014]

As described above, according to the object detecting method of the present invention, when the ambient light level is low or when the fluctuation of the ambient light level is small, the projection amount is reduced, and when the ambient light level is high or the ambient light level is high. Since the amount of light emitted is increased when the level fluctuation is large, it is possible to always perform highly accurate object detection, and when the amount of light emitted is small, the amount of light emitted is reduced accordingly. It is possible to reduce current consumption and prolong the life of the light emitting element.

[Brief description of drawings]

1 is a flow chart illustrating the method of the present invention.

FIG. 2 is a block diagram of an automatic water supply / warm air control device.

FIG. 3 is a flowchart illustrating an automatic water supply and hot air control method.

FIG. 4 is a configuration diagram of an automatic faucet.

FIG. 5 is a vertical sectional view of an automatic hand dryer.

[Explanation of symbols]

 10 Microcomputer 14 Light-Emitting Element 16 Light-Receiving Element 28 Automatic Water Faucet 36 Hand Dryer 40 Fan 42 Air Heater

Claims (1)

[Claims] 1. A method in which light is emitted from a light emitting element and reflected light of the light is received by a light receiving element to detect an object, the ambient light level in a detection region is detected, and the ambient light level is a predetermined value. When the ambient light level is higher than a predetermined value, or when the ambient light level is higher than a predetermined value, the amount of light emitted from the light emitting element is reduced. The object detection method is characterized in that the amount of light projected from the light emitting element is increased when the value is larger than the value of.