JPH04218704A - moving object detector - Google Patents

Abstract

PURPOSE:To enable a difficult alignment of a light axis to be performed easily in the case of a detector of a moving object consisting of a photosensor which receives light emitted to the moving object by using an optical fiber. CONSTITUTION:A fluorescent fiber is used at a light-receiving part. A fluorescent matter is included in a core material at the fluorescent fiber and one part of fluorescence which is generated by a light which hit against the fluorescent substance propagates within a core and exits from a tip as in a normal optical fiber. This fluorescence is guided to a light receiving device such as a photodiode by the optical fiber and is converted to an electrical signal. A light axis needs to be adjusted only in a direction which is at right angle to the fluorescent fiber since an entire length of the fluorescent fiber functions as the light-receiving part, thus enabling the light axis adjustment to be made easily. The fluorescent fiber may be fixed or mounted to a moving object. Also, an irradiation part which is mounted to the tip of the optical fiber at an emission side can be fixed to a structure or can be mounted to the moving object.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] This invention is useful for detecting the position of a moving object, such as detecting the position of a movable contact of a circuit breaker by detecting that a movable part interrupts light. Object detectors, especially when the moving object is a high-voltage electrode or there is a high-voltage electrode nearby, receive light through an optical fiber, convert it into an electrical signal by a photoelectric converter installed at the ground voltage section, and then detect the moving object. The present invention relates to a moving object detector that performs electronic circuit processing to detect the position of a moving object.

0002

[Prior Art] Optical sensors can be used as moving object detectors to detect the position of moving objects using light, and can be used in a non-contact manner. Often used. Also, L
The light emitted by light emitting devices such as EDs and laser diodes, and the photoreceptors such as photodiodes and phototransistors that receive this light and convert it into electrical signals, use metal and are connected to leads, so do not place them near high-voltage parts. It cannot be installed in Therefore, a convenient optical sensor uses an optical fiber to guide light from a light emitter to a predetermined position, emits light in a predetermined direction, receives this light with an optical fiber, guides it to a receiver, and converts it into an electrical signal. Alternatively, there is a reflective optical sensor in which a light emitter and a light receiver are fixed so as to face substantially the same direction, and the light receiver receives reflected light that is irradiated onto a moving object and reflected.

0003

In the case of an optical sensor using such an optical fiber on at least one of the light emitting side and the light receiving side, there is a problem that it is difficult to align the optical axes with each other. Optical sensors that do not require alignment of optical axes have been manufactured in which a light emitter and a light receiver are fixed facing each other across a space, and a moving object is moved within this space. It cannot be used in areas where high voltage electrodes are present,
Another problem is that there are significant restrictions on the space in which moving objects can be placed. In addition, in the case of a reflective type optical sensor, there is a problem in that both the light emitter and the light receiver must be focused on the surface of the moving object, and there are restrictions on the focal length.

An object of the present invention is to solve these problems and provide a moving object detector equipped with an optical sensor whose optical axis can be easily adjusted. It is about providing.

[0005]

[Means for Solving the Problems] In order to solve the above problems, according to the present invention, a light emitter, a power source for the light emitter, a light receiver, and an electric signal received and converted by the light receiver are inputted. a detection means equipped with a processing circuit for electronic circuit processing; a light emitting means comprising an optical fiber that guides the light emitted by the light emitting device; and an irradiation section attached to the tip of the optical fiber; A moving object, comprising a light receiving unit consisting of a light receiving section that receives light and an optical fiber that guides the received light to the light receiver, and the detecting means detects the position of the moving object based on the intensity of the converted electric signal. In the detector, the light-receiving section of the light-receiving means is made of a fluorescent fiber, and the fluorescent fiber is arranged in a direction substantially perpendicular to the optical axis of the light emitted by the light-emitting means; A fluorescent fiber and a fluorescent fiber are placed facing each other across a moving space of a moving object, or a fluorescent fiber is attached to a moving object, or an irradiation part is attached to a moving object. .

[0006]

[Operation] In the structure of the present invention, when the light receiving section of the light receiving means is constructed of a fluorescent fiber, when this fluorescent fiber is irradiated with the light emitted from the light emitting means, fluorescence is generated inside and a part of the light is emitted from the fluorescent fiber. The light propagates inside and exits from the tip, so the entire length of the fluorescent fiber becomes the light receiving section. Since the light receiving part of this fluorescent fiber is linear, the optical axis of the light emitter only needs to be aligned in a direction perpendicular to the direction in which the fluorescent fiber is arranged. Further, by arranging the light emitter and the fluorescent fiber so as to face each other across the moving space of the moving object, the position of the moving object can be detected without contacting the moving object. Alternatively, when a fluorescent fiber is attached to a moving object, the optical fiber that optically connects the fluorescent fiber and the receiver is highly flexible, so there is no problem with the movement of the moving object, and the optical fiber has excellent insulation properties. Therefore, even if the moving object is a high voltage electrode, there is no problem with insulation.
The present invention can be applied even if there is no structure suitable for attaching fluorescent fibers. Alternatively, if the light emitter is attached to a moving object, the invention can be applied even without a structure to which the light emitter is attached, or the fluorescent fiber can be attached to a fixed high voltage electrode.

[0007]

EXAMPLES The present invention will be explained below based on examples. FIG. 1 is a conceptual diagram showing an embodiment of the invention. In this figure, a detector 5 includes a light emitting device such as a light emitting diode (not shown), its power source, a photodetector such as a photodiode, and an electronic device that amplifies the electrical signal converted by the photodetector and detects the position of a moving object based on the intensity of the signal. It consists of a circuit.

The light emitted by the light emitter of the detection circuit 5 is guided to an optical fiber 31 and irradiated from an irradiation section 32 attached to the tip of the optical fiber 31. The irradiation unit 32 is attached to a structure 33 of the apparatus in which the moving object detector is installed. The fluorescent fiber 1 is also attached to another structure 11 and is installed so that the light 6 irradiated from the irradiation section 32 hits the fluorescent fiber 1.

The irradiation unit 32 has a lens for focusing the light emitted from the tip of the optical fiber 31 at a predetermined position or for converting it into parallel light, and the member supporting this lens is metal. Therefore, if the structure 33 is a high voltage electrode, it is not appropriate to attach it to this, but it is appropriate to attach it to the ground electrode. The fluorescent fiber 1, like a normal optical fiber, consists of a core and a cladding that covers the outside and has a higher refractive index than the core. The difference from ordinary optical fibers is that the core material contains a fluorescent substance, and the fluorescent substance emits a unique fluorescence when light penetrates from the outside through the cladding. Among the components of this fluorescent light, components below a predetermined angle with respect to the axis of the fluorescent fiber are totally reflected by the cladding, propagate along the axis without leaking outside, and exit from both ends.

Fluorescence generated when the light 6 enters the fluorescent fiber propagates within the fluorescent fiber 1, passes through the optical fiber 2, enters a light receiver in the detector 5, and is converted into an electrical signal. When the moving object 4 blocks the light 6, the light no longer enters the fluorescent fiber 1, so the intensity of the electrical signal converted from the optical signal within the detector 5 becomes zero. In this way, by detecting whether the moving object is in a position that blocks the light 6, the position of the moving object can be known.

Since the fluorescent fiber 1 is long and thin, it is only necessary to align the optical axis, which is the path of the light 6, in a direction perpendicular to the direction of the fluorescent fiber 1, which facilitates optical axis alignment. Furthermore, by arranging one fluorescent fiber so that a plurality of fluorescent fibers 1 are lined up, the width dimension in the direction in which optical axis alignment is required is increased, and a configuration is adopted in which optical axis alignment becomes easier. You can also do that.

FIG. 2 is a conceptual diagram showing another embodiment of the present invention, and the same members as those in FIG. 1 are given the same reference numerals and detailed explanations will be omitted. In this figure, the fluorescent fiber 1 is attached to a moving object 4, and as the moving object 4 moves, the fluorescent fiber 1 also moves, so that the detector 5 can detect that the light 6 hits the fluorescent fiber 1. In the figure, the direction of the fluorescent fiber 1 is vertical, so when the moving object 4 moves in a direction perpendicular to the figure, the electrical signal is no longer 0 for a short time when the light 6 hits the fluorescent fiber 1, and this is detected. be able to. Furthermore, when the moving object 4 moves in the same direction as the fluorescent fiber 1, it emits fluorescence when the light 6 is between both ends of the fluorescent fiber, and stops emitting fluorescence when it moves away from both ends, so the fluorescent fiber 1 to an appropriate length, the position of the moving object 4 can be adjusted by setting the fluorescent fiber 1 to an appropriate length.
It can be detected within a range corresponding to the length of .

Since the optical fiber 2 is thin and highly flexible, it does not become an obstacle to the movement of the moving object 4, and the optical fiber 2 itself does not break due to bending stress. Furthermore, even if the moving object 4 is a high-voltage electrode, no problem will occur in terms of insulation strength because the optical fiber 2 has excellent insulation properties.

FIG. 3 shows another embodiment of the present invention, and similar to FIG. 2, detailed explanation of the same members as in FIG. 1 will be omitted. In this figure, the fluorescent fiber 1 is attached to the structure 11 in the same way as in FIG.
It was installed on. Moving object 4 in this example
The position detection function of is basically the same as in the case of FIG. That is, when the moving object 4 moves in a direction perpendicular to the drawing, the electrical signal is no longer 0 for a short period of time when the light 6 hits the fluorescent fiber 1, and this can be detected. Furthermore, when the moving object 4 moves in the same direction as the fluorescent fiber 1, it emits fluorescence when the light 6 is between both ends of the fluorescent fiber 1, and stops emitting fluorescence when it moves away from both ends, so it fluoresces. By setting the fiber 1 to an appropriate length, the position of the moving object 4 can be detected within a range corresponding to the length of the fluorescent fiber 1. Like the optical fiber 2, the optical fiber 31 has excellent flexibility, so the optical fiber 31 will not become an obstacle to the movement of the moving object 4 or break.
Furthermore, no insulation problems arise.

As mentioned above, it is appropriate to attach the irradiation unit 32 to the ground electrode, so the embodiment shown in this figure
is appropriate when the ground electrode is a ground electrode or an insulator provided near the ground electrode. The structure 11 may be a high voltage electrode.

[0016]

Effects of the Invention As described above, in the present invention, when the light-receiving section is composed of a fluorescent fiber, when the light emitted from the light-emitting means hits the fluorescent fiber, the fluorescent substance contained in the core of the fluorescent fiber emits fluorescence. A portion of the fluorescent light propagates inside the fluorescent fiber and exits from the tip, so by guiding this light to the detection means, the entire length of the fluorescent fiber can be used as a light receiving section. Since the light-receiving part of this fluorescent fiber is linear, the optical axis of the light emitter only needs to be aligned in a direction perpendicular to the direction in which the fluorescent fiber is disposed, which provides the effect that the optical axis can be easily adjusted. Furthermore, if the light emitter and the fluorescent fiber are placed facing each other across the movement space of the moving object, the light will be blocked by the movement of the moving object, and by detecting this, the position of the moving object can be detected without contact. be able to. Alternatively, when a fluorescent fiber is attached to a moving object, the optical fiber that optically connects the fluorescent fiber and the receiver is highly flexible, so there is no problem with the movement of the moving object, and the optical fiber has excellent insulation properties. Therefore, even if the moving object is a high voltage electrode, there is no problem in terms of insulation, and the present invention can be applied even if there is no structure suitable for attaching the fluorescent fiber. Alternatively, if the light emitter is attached to a moving object, the invention can be applied without a structure to which the light emitter is attached, and the fluorescent fiber can be attached to a fixed high voltage electrode.

[Brief explanation of the drawing]

[Fig. 1] Conceptual diagram showing an embodiment of this invention

[Fig. 2] Conceptual diagram showing another embodiment of this invention

[Fig. 3] Conceptual diagram showing another embodiment of this invention

[Explanation of symbols]

1 Fluorescent fiber 11 Structures 2 Optical fiber 31 Optical fiber 32 Irradiation section 33 Structure 4. Moving object 5 Detector (detection means) 6. Light

Claims (4)

[Claims] 1. Detecting means comprising a light emitter, a power source for the light emitter, a light receiver, and a processing circuit that inputs an electrical signal received and converted by the light receiver and processes it in an electronic circuit, wherein the light emitter emits light. a light-emitting means comprising an optical fiber that guides the light and an irradiation part attached to the tip of the optical fiber; a light-receiving part that receives the light emitted from the irradiation part of the light-emitting means; and an optical fiber that guides the received light to the light receiver. A moving object detector comprising a light receiving means, the detecting means detecting the position of the moving object based on the intensity of the converted electric signal,
A moving object detector characterized in that the light receiving section of the light receiving means is made of a fluorescent fiber, and the fluorescent fiber is arranged in a direction substantially perpendicular to the optical axis of the light emitted by the light emitting means. 2. The moving object detector according to claim 1, wherein the irradiating section and the fluorescent fiber are arranged to face each other with a movement space of the moving object interposed therebetween. 3. The moving object detector according to claim 1, wherein the fluorescent fiber is attached to the moving object. 4. The moving object detector according to claim 1, wherein the irradiation section is attached to the moving object.