JPH0731478Y2 - Photoelectric switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a photoelectric switch.

[Conventional technology]

Photoelectric switches based on the optical triangulation method, for example,
The principle is explained in Japanese Utility Model Application No. 61-126857. As shown in FIG. 3, the switch includes an optical block S, and the block S includes an optical block body 1 made of a plastic material. The main body 1 is a substantially rectangular parallelepiped and is partitioned by a wall 1a in the middle to form a frame shape having two parallel cylindrical spaces. One of the two cylindrical spaces is provided with a light projecting lens 2 and The light receiving lenses 3 are incorporated in the other side, respectively. This assembling is shown in FIG. 4 by enlarging it, and the ear-like protrusions 2a, 2a, 3a, 3a provided on the outer periphery of each lens 2, 3 are provided in the groove 1b provided in the block body 1 It is done by fitting it into …… and fixing it with an adhesive. An optical filter 4 is provided on the front side of the block body 1 to regulate the incidence of ambient light.
Are fixed by an adhesive. As shown in FIG. 3, a light projecting element and a light receiving element (position detecting element) 5 are incorporated in the rear portion of each cylindrical space of the block body 1, and these are respectively a light projecting lens 2 and a light receiving lens 3. Located behind each. The position detecting element 5 is provided with a printed wiring board 6 on its back. The printed wiring board 6 is attached to the back of the block body 1, and the position detecting element 5 is adjusted to an appropriate position and angle. The optical block S is soldered to the circuit block 10 via the printed wiring board 6, and the both blocks S, 10 are placed in a main body case 12 having an opening on the entire side surface and a part of the front surface. After that, the side opening of the main body case 12 is hermetically closed by the lid 13. At that time, the power line 14 is taken out through the through hole 12a formed in the main body case 12 through the cord bush 15, and the optical filter 4 is fitted into the front opening 12b of the main body case 12. Has become. After the lid 13 is attached, in order to make the photoelectric switch waterproof type,
The case 1 through the injection port 12c opened in the body case 12
Resin is injected into 2 and the filling state is maintained.

[Problems to be solved by the device]

By the way, the both lenses 2 and 3, the projecting pieces 2a, 2a, 3a on each side,
Although 3a is fitted into the groove 1b of the optical block body 1 and fixed by an adhesive, the groove 1b
.. is deeper than the thickness of the protrusions 2a and 3a, and moreover, the back surface of the optical filter 4 is flat and is positioned apart from the protrusions 2a and 3a in the front side. As a result, it was necessary to perform positioning by a jig so that both lenses 2 and 3 would not float in the z direction in FIG. As described above, in order to make it waterproof, the case 12 is filled with resin at the end, but if there is a gap between the front and rear of the optical filter 4 and each of the projecting pieces 2a, 3a, the resin will flow from there. May invade. Therefore, additional work has been required, for example, it is necessary to previously seal the gap with taping or a resin having high viscosity.

The present invention has been made in view of the above circumstances, and its problem is that additional work is not required for positioning the lens and preventing resin or the like from entering the optical block. It is to be done.

[Means for Solving the Problems]

In order to solve the above problems, a photoelectric switch according to the present invention includes an optical block body and a case that houses the same, and the block body focuses a light beam from a light emitting element and irradiates it in a certain direction. And a light-receiving lens that focuses a part of the light beam reflected by the object to be detected and makes it incident on the position detection element, and the projection is provided on the outer circumference of each lens. Made to fit into the groove provided in the block body, and
An optical filter is disposed on a front surface of the block body through which the light rays pass, and the block body is housed and filled with resin in the case so that the optical filter is located in an opening provided in the case. In the photoelectric switch according to the first aspect of the invention, the optical filter is provided with a portion that fits into the groove so as to press the both lenses and seals the inside of the optical block body from the outside.

[Action]

If the optical filter is provided with a portion that fits into the groove so as to press the both lenses and seals the inside of the optical block main body with respect to the outside, the filter is a lens positioning jig. In order to prevent the ingress of waterproof resin, which plays a role and does not require a separate positioning jig,
There is no need for taping or filling resin with high viscosity.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings showing an embodiment thereof.

1 and 2 show an embodiment of the photoelectric switch according to the present invention. In these drawings, only an optical block is shown, and the block is provided with an optical block body 20 made of a plastic material. The main body 20 is substantially a rectangular parallelepiped and is partitioned by a wall in the middle to form a frame shape having two parallel cylindrical spaces. One of the two cylindrical spaces is provided with a light projecting lens 21, and the other is The light receiving lenses 22 are incorporated in the respective. This assembling is performed by the ear-shaped protrusions 21a, 21a, 22a, 2 provided on the outer periphery of each lens 21, 22.
2a is fitted in the groove 20b provided in the block body 20 and is fixed by an adhesive or the like. An optical filter 23 is fixed to the front side of the block body 20 with an adhesive. At the rear of each cylindrical space of the block body 20, a light projecting element 24
And a position detecting element 25 are respectively incorporated therein, and these are respectively located behind the light projecting lens 21 and the light receiving lens 22. The light projecting element 24 is fixed to the optical block body 20 with an adhesive 27. The position detecting element 25 is attached to the back portion of the optical block body 20 together with the printed wiring board 26 on the back portion thereof, and then adjusted to an appropriate position and angle. The optical block is soldered to a circuit block (not shown) via the printed wiring board 26, and both of these blocks are put in the main body case where the entire side surface and a part of the front surface are opened, and thereafter, The side opening of the main body case is configured to be closed by a lid. The optical filter 23 arranged on the front surface of the block main body 20 through which the light rays pass is fitted into the front opening of the case so that the engaging groove 23a of the filter 23 is aligned with the groove of the main body case. . After the lid is attached, in order to make the photoelectric switch waterproof type, the resin is injected into the case through the injection port opened in the case, which is the same as above. .

By the way, the optical filter 23 is not a flat one, but has an upper portion in the shape of a plate having a rectangular shape and the engaging groove 23a on the outer periphery, and a lower portion has a peripheral wall integrally protruding downward from the outer peripheral edge portion of the upper portion. It is part 23b. Then, from the four points on the bottom surface of the upper portion, the projections 23c are formed so as to project downward.
Are provided, and these protrusions 23c ...
Of the protrusions 21a, 21a, 2 while fitting in the grooves 20b of the
2a and 22a are pressed from the front (upper side in the figure). At this time, the inner back surface 23d of the upper part has a minute gap in the front surface 20c of the block body 20. This is because the protrusion 23 between the filter 23 and the block body 20
This is because the positioning is surely performed by using only c ... And the protruding pieces 21a, 22a. The gap is such that resin does not enter. The peripheral wall portion 23b is adapted to fit on the outer peripheral surface 20d of the front portion of the block body 20, and the rear portion of the peripheral wall portion 23b is provided with other protrusions 23e ... The grooves 20b ... Are closed from the outside in a hermetically sealed manner.

As described above, in the photoelectric switch according to the present invention, the optical filter is provided with a portion that is fitted into the groove so as to press the both lenses and seals the inside of the optical block body from the outside. Since the filter acts as a lens positioning jig and does not require a separate positioning jig, taping and filling of highly viscous resin are necessary to prevent ingress of waterproof resin. Disappear.

[Effect of device]

Since the photoelectric switch according to the present invention is configured as described above, no additional work is required to position the lens and prevent resin from entering the optical block, and assembly is performed efficiently. It became so.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a photoelectric switch according to the present invention in an assembled state of an optical block, FIG. 2 is an exploded side view thereof, and FIG. 3 is an overall perspective view showing a conventional photoelectric switch disassembled. FIG. 4 is an exploded perspective view showing an optical block main body in which a lens is incorporated and a filter based on FIG. 20 ... Optical block body, 20b ... Groove, 21 ... Emitting lens, 22 ... Receiving lens, 23 ... Optical filter, 23c ...
… Protrusion, 23e …… Protrusion, 24 …… Projector element, 25 …… Position detection element

Claims (1)

[Scope of utility model registration request] 1. An optical block main body and a case for accommodating the main body, and the block main body has a light projecting lens for converging and irradiating a light beam from a light emitting element in a fixed direction.
A light-receiving lens that focuses a part of the light beam reflected by the object to be detected and makes it incident on the position detection element is incorporated, and the same projection is provided on the block main body on the outer periphery of each lens. It is made to fit in the groove,
And, an optical filter is disposed on the front surface of the block body through which the light rays pass, and the case is housed in the case such that the block body is housed so that the optical filter is located in an opening provided in the case. In the photoelectric switch to be filled, the optical filter is provided with a portion that fits into the groove so as to press the both lenses and seals the inside of the optical block body from the outside. Photoelectric switch characterized by.