JPH073361Y2 - Fiber optic sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a sensor using an optical fiber.

[Conventional technology]

As shown in FIG. 7, an optical fiber sensor using an optical fiber comprises a detection section (2) and optical fibers (3) and (4) connecting the detection section (2) to an output device (1). Although not shown, the output device (1) includes a light emitting element such as a light emitting diode, a light receiving element such as a phototransistor, and an amplifier for amplifying a signal of the light receiving element. A tip mouthpiece (5) for attaching the tip surfaces of the optical fibers (3) and (4) to the detected portion is used for the detection portion (2). The tip base (5) is, for example, a cylindrical metal ring with a collar, and accommodates the tips of the optical fibers (3) and (4).
Both of them are aligned with each other, and they are solidified with resin (6) or the like and integrally bonded. The rear ends of the optical fibers (3) and (4) are connected to the output device (1) via the optical connector (7). The optical fibers (3) and (4) are covered with an outer cover (8) between the tip base (5) and the optical connector (7).

In the optical fiber sensor, the output device (1) is installed in the control part of the equipment, and the tip base (5) is installed in the operating part. Then, the light emitted from the light emitting element of the output device (1) is transmitted by one of the optical fibers (3) to cause the tip of the tip base (5) to emit light. When the detected component (9) faces the front of the tip base (5) and the light is reflected, the reflected light is transmitted to the output device (1) by the other optical fiber (4), and the light is received by the light receiving element. Is received and emits a signal, and the detected part (9)
To detect.

[Problems to be solved by the device]

Although the above optical fiber sensor is used in various equipment, when it is used in welding equipment, the detection part (2) is placed close to the welding machine, so the spatter (10) scattered during welding is as shown in FIG. In addition, there is a problem that the optical fibers (3) and (4) adhere to the tip surfaces of the optical fibers and detection cannot be performed.

When the spatter (10) adheres to the tip surfaces of the optical fibers (3) and (4) as described above, the spatter (10) cannot be removed and the tip base (5) cannot be replaced. Therefore, the entire optical fiber sensor, that is, the tip base (5) ) To the optical connector (7) were exchanged together with the optical fibers (3) and (4). Therefore, it was wasteful and costly.

In this invention, an optical fiber sensor is attached so that an optical fiber can be slid relative to the tip base, and when the tip of the optical fiber becomes defective, the tip of the optical fiber is drawn out from the base and the defective portion of the optical fiber can be cut and removed. It is the one we are trying to provide.

[Means for Solving the Problems]

The optical fiber sensor in the present invention has a cylindrical base body in which a front portion is formed thicker than a rear portion from an intermediate portion, a male screw is engraved on an outer peripheral surface, and the front portion is divided into a plurality of diameters to expand the diameter. An elastic member that is slidably held by the nut that reduces the diameter of the tip of the base by screwing it into the base of the base and moving it toward the tip side, the optical fiber, and the end of the optical fiber. The holding member is made of a body.

[Action]

In the optical fiber sensor having the above structure, the nut is moved to the tip side of the base body, the tip of the base body is reduced in diameter, and the holding member is tightened to firmly hold the optical fiber.

If the tip of the optical fiber becomes defective, move the nut to the rear of the base body, expand the tip of the base body to open the optical fiber, pull out the tip of the optical fiber from the tip of the base body, and cut and remove the defective part. After that, the nut is moved to the tip side to reduce the diameter of the tip of the base body, and the holding member is tightened to firmly hold the optical fiber for reuse.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6. Incidentally, in FIG. 1, the same components as those in FIG. 7 are designated by the same reference numerals, and the description thereof will be omitted.

The tip mouthpiece that constitutes the detection section (2) is composed of a mouthpiece body (11), nuts (15) (16), and a holding member (17).
As shown in FIGS. 1 to 3, the base body (11) is formed of a cylindrical metal ring having a spring property in which the front portion is thicker than the rear portion, and a male screw is formed on the entire outer peripheral surface thereof. (12) is engraved and slits (13) in the axial direction from the tip side at several points in the circumferential direction.
(13) ... Have a proper length and the tip portion is divided into a plurality of pieces, and the divided pieces (14), (14) ... are inclined outward. The nuts (15) (16) are screwed onto the male threads (12) of the base body (11), and the tip nut (15) expands the split pieces (14) (14) of the base body (11). Reduce the diameter and diameter, and position the rear end side nut (16) during mounting. The holding member (17) is formed of an elastic member such as rubber in a cylindrical shape, and through holes (18) and (19) through which the optical fibers (3) and (4) pass are formed inside the holding body (11). It is housed in. When the holding member (17) is in the free state, the optical fiber (3)
(4) is opened and the divided pieces (14) (14) of the base body (11) are opened.
When it is tightened with ..., The tip portion is elastically deformed and holds the optical fibers (3) and (4).

In the optical fiber sensor having the detecting section (2) having the above structure, the tip side nut (15) is moved to the tip side of the base body (11), and the nut (15) divides the split pieces (14) (14) ... The optical fiber (3) (4) is fixed by tightening the holding member (17) with the divided pieces (14) (14) ..., and the tip end surface of the fiber (3) (4) is fixed to the base body (11). ) Match the tip surface of. Then, the rear portion of the base body (11) is attached to the attachment portion near the detection position, and the nut (16) is used for positioning.

If spatter (10) adheres to the tip surfaces of optical fibers (3) and (4) during use and cannot be detected, the tip nut (15) is moved backward as shown in FIG. (1
4) Expand the diameters of (14) ..., and release the fixation of the optical fibers (3) and (4) by the holding member (17). After this, as shown in FIG. 5, the holding members (17) are attached to the optical fibers (3) and (4).
From there, the optical fibers (3) and (4) are cut to remove the defective portion (18). After that, as shown in FIG. 6, the optical fibers (3) and (4) are returned so that their tip surfaces are aligned with the tip surface of the base body (11), and then the tip nut (15) is moved forward. Optical fiber (3) by reducing the diameter of the divided pieces (14) (14) ... and tightening the holding member (17).
Fix (4) and perform detection again.

[Effect of device]

According to this invention, even if the tip of the optical fiber becomes defective, the tip of the optical fiber can be pulled out from the base of the base to cut and remove the defective part, and the base of the base and the optical fiber can be used many times. It becomes unnecessary and the repair cost can be greatly reduced. Further, since the repair can be easily performed, the work stoppage time can be shortened and the workability is greatly improved.

[Brief description of drawings]

FIG. 1 is a front view of an optical fiber sensor according to the present invention,
2 is an enlarged plan view of the detecting portion, FIG. 3 is an enlarged sectional view of the detecting portion, and FIGS. 4 to 6 are enlarged sectional views showing repair work.
FIG. 7 is a perspective view of a conventional optical fiber sensor, and FIG. 8 is an enlarged cross-sectional view of an essential part showing a problem. (1) ... Output device, (2) ... Detection unit, (3) (4) ...
… Optical fiber, (11) …… Base body, (12) …… Male screw, (13) …… Slit, (14) …… Divided piece, (15)
(16) …… Nut, (17) …… Holding member.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G01N 21/15 9118-2J G01V 8/16

Claims (1)

[Scope of utility model registration request] 1. The intermediate part to the front part is formed to be thicker than the rear part,
By engraving a male screw on the outer peripheral surface and dividing the tip into multiple parts and expanding the diameter, the tip of the mouthpiece body is screwed into the mouthpiece body and moved to the tip side. An optical fiber sensor including a nut for reducing the diameter, an optical fiber, and an elastic holding member that slidably holds the tip of the optical fiber and is housed in the base of the base.