JPH04215221A - Limited sensitivity type sensor - Google Patents

Abstract

PURPOSE:To obtain a limited sensitivity type sensor having the simple structure to be housed in a single box body and having the high function for sensitizing human beings and articles in multiple positions respectively having a different distance from a light sensor with one projecting element and one light receiving lens. CONSTITUTION:One projecting element 2 and multiple light receiving elements 4, 5 are comprised, and one light receiving lens 3 is located so that an optical axis of the lens 3 is positioned diagonally against an optical axis of the described projecting element 2, and the described multiple light receiving elements 4, 5 are located in rear of the light receiving lens 3 and in different focus point positions against the optical axis of the light receiving lens 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a limited sensing type sensor that detects the presence or absence of an object at a plurality of locations.

0002

2. Description of the Related Art FIG. 3 shows a schematic configuration of a reflective optical sensor. In the figure, reference numeral 1 denotes an optical sensor, which is composed of a light projecting element 11, a light receiving element 12, and a condensing lens 13. Light projecting element 11
A light signal such as infrared rays emitted by an object hits an object and is reflected,
Object sensing was performed by condensing the reflected light onto the light receiving element 12 using a condensing lens 13.

However, in such conventional optical sensors,
Since the configuration detects the presence or absence of an object using the on/off signal from the light receiving element 12, only one type of object could be detected.

For example, in an automatic hand washer/dryer having the circuit configuration shown in FIG. 4, two optical sensors 10 and 20 are provided to detect the approach of hands at different positions A and B. When the hand is brought to point A, the infrared rays emitted from the light projecting element 11 are reflected by the hand, enter the light receiving element 12 via the condensing lens 13, and a sensing signal is output. The controller 6 receives this signal and drives the solenoid valve 7 to discharge water from the faucet. When you bring your hand to point B after cleaning, the infrared rays emitted from the light emitting element 21 are reflected by your hand, enter the light receiving element 22 through the condensing lens 23, and
A sensing signal is output. The controller 6 receives this signal and drives the fan 8 to dry the hands.

[0005] In this way, if it is desired to operate different devices depending on the position of an object, separate sensors must be provided for each device, which poses problems in terms of installation space and cost.

[0006] Conventionally, an optical relay equipped with one light source and two light receiving elements has been proposed as a device for sensing the direction of a person passing (Japanese Patent Laid-Open No. 57-63734, Japanese Patent Laid-Open No. 57-57). 63735). This is equipped with optical systems each consisting of a light receiving lens and a light receiving element on both sides of the light source.

[0007]

[Problems to be Solved by the Invention] However, although this conventional optical relay can detect the direction in which a person passes, it cannot detect the presence or absence of a person at multiple positions at different distances from the optical sensor. I couldn't. Furthermore, the structure was complex and it was impossible to house it in a single housing.

The present invention is a highly functional limited sensing type that has a simple structure, can be housed in a single housing, and can detect people and objects at multiple positions at different distances from the optical sensor. The purpose is to provide sensors.

[0009]

[Means for Solving the Problems] In order to achieve this object, the limited sensing type sensor of the present invention is provided with one light emitting element and a plurality of light receiving elements, and with respect to the optical axis of the light emitting element. Arrange one light receiving lens so that the optical axis is positioned diagonally.
The light receiving element is characterized in that each of the plurality of light receiving elements is arranged behind the light receiving lens at different focal positions with respect to the optical axis of the light receiving lens.

0010

[Operation] Since the present invention has the above structure, each of the light receiving elements senses the presence or absence of an object on the straight line connecting the light receiving element and the optical center of the light receiving lens. Therefore, it is possible to sense objects at a plurality of positions at different distances from the light projecting element.

[0011]

EXAMPLES The present invention will be specifically explained below based on examples.

FIG. 1 is a schematic diagram showing the configuration of the present invention. In the figure, an optical sensor 1 includes a light projecting element 2 that emits infrared rays, a light receiving lens 3, and two light receiving elements 4 and 5. The light receiving lens 3 is arranged so that its optical axis is oriented obliquely to the optical axis of the light projecting element 2. Light receiving elements 4 and 5 are arranged at the focal position behind the light receiving lens 3, and the optical axis of the light projecting element 2 is an extension of a straight line connecting the light receiving elements 4 and 5 and the optical center of the light receiving lens 3. Object A to be detected at the intersection with
, so that the positions of B are aligned.

When the light (infrared rays) emitted from the light projecting element 2 is reflected at the position of the object A, it is detected by the light receiving element 5, and the light is reflected at the position of the object B.
If it is reflected at the position, it is detected by the light receiving element 4.

In this way, the light emitted from one light emitting element 2 is used to individually target objects at two different positions to the light receiving elements 4 and 5.
can be sensed.

Note that when object A and object B are present on the optical axis of the light projecting element 2 at the same time, the light of object B will be blocked by object A, so object A cannot be sensed preferentially. can.

FIG. 2 shows an embodiment in which an automatic hand washing/drying device is driven using the optical sensor having the above configuration. In the figure, when a hand is detected within point A from the light emitting element 2, a sensing signal is output from the light receiving element 5, and when a hand is detected between point A and B, the sensing signal is output from the light receiving element 4. A sensing signal is output.

By controlling each of these signals with the controller 6, if a human hand comes between point A and point B,
A solenoid valve 7 for washing hands is driven, and when a person's hand comes within point A, a fan 8 for drying wet hands is driven.

[0018] In the above embodiments, the case where there are two light-receiving elements has been described, but similarly, when the number of light-receiving elements increases to n, it is possible to operate n devices by controlling the controller.

[0019]

[Effects of the Invention] As explained above, according to the present invention, one optical sensor is provided with optical sensors that individually detect the positions of a plurality of objects. It is possible to save space and reduce costs.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of an optical sensor of the present invention.

FIG. 2 is a circuit diagram showing an embodiment of an automatic hand washer/dryer using the optical sensor of the present invention.

FIG. 3 is a schematic diagram showing an example of a conventional optical sensor.

FIG. 4 is a circuit diagram showing an example of an automatic hand washer/dryer using a conventional optical sensor.

[Explanation of symbols]

1. Optical sensor 2 Light projecting element 3 Light receiving lens 4,5 Photo receiving element 6 Controller 7 Solenoid valve 8 Fan

Claims (1)

[Claims] 1. A light-emitting element comprising one light-emitting element and a plurality of light-receiving elements, one light-receiving lens arranged so that its optical axis is positioned obliquely to the optical axis of the light-emitting element, A limited sensing type sensor, characterized in that each of the plurality of light receiving elements is arranged behind a light receiving lens at different focal positions with respect to the optical axis of the light receiving lens.