JPS6235236Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a light beam detector unit. Conventionally, it is known that optical detector units are assembled on a printed board, but in the optical detector unit that uses a convex lens A, a cylindrical lens is inserted perpendicularly from the printed board surface B in order to hold the lens A. Since the holding part C was added, the optical system became larger, and since the printed board surface and the lens surface were arranged parallel to each other, when this unit was incorporated into a device, it would be difficult to install due to vibrations. It was often unstable.

The present invention is aimed at improving the above-mentioned drawbacks, and includes a first printed board to which a lens is attached, and a second printed board arranged at right angles to the first printed board at a position approximately at the focal length of the lens. It includes a second printed board and a photoelectric conversion element mounted on the second printed board at a position where the optical axis of the lens intersects, and an external connection terminal and a mounting means are attached to the first printed board. It is equipped with a light beam detection unit. The present invention will be described in detail below based on one embodiment.

The embodiment is a unit that includes both a light emitting part and a light receiving part. It is composed of an object surface reflecting mirror 4. The semi-parabolic reflector 4 is molded from thermoplastic resin and plated with metal on the surface.Also, it may be formed by metal die casting, but the higher the reflectance, the better. The light is projected as parallel rays by this semi-parabolic reflecting mirror 4. The light receiving section 5 includes convex lenses 6 and 7 provided on both sides of the light emitting section 1, and light receiving elements 8 and 9 located approximately at the focal point of the convex lenses.

Note that the semi-parabolic reflector 4 and the convex lenses 6 and 7 are the first
It is fixed to a mounting plate 10 whose surface is painted black, which is mounted on a printed board 3. For example, the semi-parabolic reflector 4 is connected to the screws 11, 11, and the convex lenses 6, 7 are connected to the slit 13 of the cut-out portion 12 provided on the mounting plate 10.
The edges of the convex lenses 6 and 7 are fitted to the edges of the convex lenses 6 and 7, and the tips 16 and 16 of the wire springs 15 held by the holding tongues 14 and 14 cut and raised from the mounting plate 10 are used to press and hold the lenses downward. Incidentally, if the convex lenses 6 and 7 are made of plastic as shown in FIG. 4, and a notch 6' is formed through which the wire spring 15 can slide, the holding can be ensured. The second printed board 17 is attached to the first printed board 3 at right angles, and the light receiving elements 8 and 9 attached to the second printed board are connected to the convex lenses 6 and 9.
It is installed in such a way that it is located almost at the focal point of 7. The light-receiving elements 8 and 9 are covered with a cover 18 having holes 18 as shown in FIG. 5 to prevent external light from entering. Electronic components 20, 20 constituting the electric circuit section are soldered to the first and second printed boards 3, 17, and have a circuit configuration shown in the block diagram of FIG. 6. Reference numeral 24 denotes a light emitting circuit, which is comprised of a driving circuit 26 for the light emitting element 2 that operates intermittently at the cycle of an oscillation circuit 25. 27 and 28 are circuits for processing the signals received by the light receiving elements 8 and 9, which include a tuning amplification circuit synchronized with the period of light emitted from the light emitting element 2, a detection circuit, a low pass filter, a low pass amplifier, Consists of a waveform shaping circuit. Reference numeral 29 denotes a movement direction determining circuit for determining the order in which light is received by the light receiving elements 8 and 9, and is comprised of, for example, a differential phase detection circuit, an in-phase detection circuit, etc., and detects the order in which light is received by the light receiving elements 8 and 9. Reference numerals 21 and 21 are holes through which the mounting screws 22 pass, and 23 is a terminal portion for extracting signals from this unit to the outside or receiving a voltage supply from the outside.

This light beam type detection unit has an object detection function by itself, and blocks the light emitted from the light emitting element 2 when the object passes through, and the light reflected by the object is passed through the lenses 6 and 7. The light is received by the light receiving elements 8 and 9 via the signal processing circuits 27 and 2.
8, the moving direction determining circuit 29 detects whether the object has moved in the direction (X) or (Y) in FIG.
3 to the outside.

As described above, according to the present invention, there is provided a first printed board to which a lens is attached, a second printed board disposed perpendicularly to the first printed board at a position approximately at the focal length of the lens, and a second printed board arranged at right angles to the first printed board at a position approximately at the focal length of the lens; The optical detector unit includes a photoelectric conversion element mounted at a position on the second printed board that intersects the axes, and the first printed board is provided with an external connection terminal and a mounting means. Since this detector unit alone has a detection function, even if this unit is incorporated into a container to make a light beam detector, the quality performance can be confirmed with this unit alone, which is convenient for manufacturing, and can be used with other equipment or decorations. When this unit is incorporated into a product, it has the advantage that it can be incorporated after checking the quality of the unit alone.

Also, since the second printed board 17 is attached and fixed at right angles to the first printed board 3, the convex lenses 6, 7
It is possible to focus on the light receiving elements 8 and 9 without attaching a cylindrical lens holder as in the conventional example, resulting in a compact size. Further, since the mounting screw holes 21, 21 are provided in the first printed board 3, stable mounting is possible. Furthermore, the convex lenses 6 and 7 can be easily attached using the wire springs 15 and the mounting plate 10,
This has the effect of reducing the weight of the optical system and being able to be mounted without protruding too much from the printed board 3.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional example of this invention, Figs. 2 to 6 show an embodiment of the invention, Fig. 2 is a perspective view, Fig. 3 is a front view, and Fig. 4 is a convex lens. 6 and 7, FIG. 5 is a sectional view of the cover 19 covering the light receiving element, and FIG. 6 is a block diagram. DESCRIPTION OF SYMBOLS 1... Light emitting part, 2... Light emitting element, 3... First printed board, 4... Semi-parabolic reflecting mirror, 6, 7...
Convex lens, 8, 9... Light receiving element, 10... Mounting plate, 17... Second printed board, 21... Mounting hole, 23... Terminal portion.

Claims (1)

[Scope of utility model registration request] a first printed board to which a lens is attached; a second printed board disposed perpendicularly to the first printed board at a position approximately at the focal length of the lens; and a second printed board at which the optical axis of the lens intersects. a photoelectric conversion element attached to a position on the printed board;
1. A light beam detector unit comprising an external connection terminal and mounting means on a printed board.