JPH02116714A - Optical encoder - Google Patents

Abstract

PURPOSE:To facilitate the incorporation of optical fibers by fitting a connector to a signal detecting element in the respective terminal parts of the optical fibers which are disposed oppositely to form an optical path and by pushing this connector removably into an optical fiber insertion hole provided in a holder which holds a rotary plate. CONSTITUTION:An insertion hole 4 is provided in the part of a holder 3 which corresponds to the position of a slit 2 of a rotary plate 1, and an optical fiber 6 having a connector 5 put on the force end is provided in this insertion hole 4 in such a manner that a flange 7 of the connector 5 is brought into contact with the outer surface of the holder 3 and that the front end face thereof is matched with the inner surface of the holder 3 so that it forms one face with the latter. The part of the flange 7 of the connector 5 is fixed to the holder 3 by bolts 11. In order to provide the optical fiber 6 in the holder 3, first the connector 5 is fitted on the terminal of the optical fiber 6, then the end faces of both of the connector 5 and the optical fiber 6 are so ground as to form one face, subsequently this connector 5 is pushed into the insertion hole 4 until the flange 7 comes into contact with the rear surface of the holder 3, and thereafter the connector 5 is tightened to the holder 3 by the bolts.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical encoder used in a motor tachometer, vehicle speed sensor, etc.

[Conventional technology and its issues]

In the optical encoder, as shown in FIG. 3, a rotary plate 1 fixed to a rotating shaft 8 is rotatably held in a holder 3, and around the rotary plate 1 there is a rotary plate 1 as shown in FIG. As shown in FIG.
The terminal portions of the optical fibers 6 connected to each other are arranged opposite to each other.

In the above, the rotation angle of the rotating shaft 8 is determined by counting the number of times that an optical path is formed between the end faces of the optical fibers 6 arranged opposite each other, and the slant 2 portion of the rotating plate 1 fixed to the rotating shaft 8 interrupts this optical path. It is measured by

By the way, in the above method of arranging the optical fibers 6 facing each other, as shown in FIG.
This is accomplished by inserting the optical fiber 6 whose end face has been polished into the insertion hole 4 as it is, and fixing it with adhesive or the like.

However, in the above method, the end face of the optical fiber is easily damaged, so the installation work must be done carefully, which takes time.
Furthermore, since the optical fiber 6 is fixed to the insertion hole 4 with adhesive, maintenance such as dust removal from the end face of the optical fiber 6 is difficult, and the cause of failure cannot be checked by the optical fiber 6 alone.

[Means to solve the problem]

The present invention was made in view of the above situation, and an object of the present invention is to provide an optical encoder that can be easily assembled, maintained and inspected.

That is, the present invention provides an optical encoder that measures a rotation angle by detecting that a light-shielding part or a light-transmitting part provided on a rotary plate interrupts an optical path in response to rotation of a rotary plate fixed to a rotating shaft. A connector is attached to the optical fiber terminal portion of the signal detection unit of the optical fiber terminal portions arranged oppositely to form the optical path, and the optical fiber is inserted through the connector provided at a predetermined location of the holder that holds the rotary plate. It is characterized by being removably disposed in the hole.

〔Example) The present invention will be specifically explained below using examples.

FIG. 1 is an explanatory diagram of one embodiment of the signal detection section of the optical encoder of the present invention. In the following figures, the same part numbers as those in the conventional example will be given the same part numbers.

An insertion hole 4 is provided in a portion of the holder 3 corresponding to the position of the slit 2 in the rotating plate 1, and a connector 5 is inserted into the insertion hole 4 at the tip.
The optical fiber 6 with the connector 5 inserted therein is arranged so that the flange 7 of the connector 5 is in contact with the outer surface of the holder 3, and the front end surface is flush with the inner surface of the holder 3.

The connector 5 is fixed to the holder 3 at the flange 7 with bolts 11.

In the above, the optical fiber 6 is placed in the holder 3 by first attaching the connector 5 to the end of the optical fiber 6, and then polishing the end surfaces of both the connector 5 and the optical fiber 6 so that they are flush with each other.
Next, this connector 5 is pushed into the insertion hole 4 until the flange 7 comes into contact with the rear surface of the holder 3, and then the connector 5 is tightened to the holder 3 with the bolts 11.

Other methods of fixing the connector to the holder include:
A method of pressing a stopper against the rear of the connector through an elastic body such as rubber, and fixing the stopper by screwing it onto the holder.
Or, there is a locking method to fix it with one touch.
Any method can be applied as long as it is removable.

Although the connector used in the present invention does not necessarily need to be provided with a flange, the presence of a flange provides advantages such as the ability to arbitrarily change the position of the optical fiber end face by interposing a spacer between the outer surface of the holder and the flange.

[Effect]

In the signal detection section of the optical encoder of the present invention, since the connector is attached to the optical fiber terminal, the optical fiber is not damaged when the optical fiber is assembled into the holder, and the connector is attached to the holder. Since it is removably attached to the insertion hole, maintenance and inspection of the optical fiber end portion can be easily performed.

〔effect〕

As described above, the optical encoder of the present invention allows easy installation of the optical fiber into the holder and maintenance and inspection of the optical fiber end portion, and has a significant industrial effect.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an embodiment of the signal detection section of the optical encoder of the present invention, FIG. 2 is an explanatory diagram of the signal detection section of a conventional optical encoder, FIG. 3 is a conceptual diagram of the optical encoder, and FIG. 4 FIG. 2 is an explanatory diagram of a rotary plate portion of an optical encoder. DESCRIPTION OF SYMBOLS 1... Rotating plate, 2... Slint, 3... Holder, 4... Insertion hole, 5... Connector, 6
...Optical fiber, 7...Flange, 8...Rotating shaft.

Claims (1)

[Claims] In an optical encoder that measures a rotation angle by detecting that a light-blocking part and a light-transmitting part provided on a rotary plate interrupt an optical path in response to rotation of a rotary plate fixed to a rotating shaft, the optical path is formed. A connector is attached to the signal detection section of the optical fiber end portion arranged oppositely to each other, and the connector is detachably attached to the optical fiber insertion hole provided at a predetermined location of the holder that holds the rotary plate. An optical encoder characterized by the following: