JPS592546Y2 - Mounting device for elements in photo detectors - Google Patents

Description

[Detailed description of the invention] This invention consists of placing a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor facing each other across a detection object passing path, and inserting a detection object such as a perforated plate or perforated tape into this path. The present invention relates to a mounting device for the above-mentioned light emitting element and light receiving element in a photodetector that detects the passing speed or position of the pixel by allowing the pixel to pass through the photodetector, and to easily ensure coaxiality between the pixel elements and ensure reliable mounting. With the goal.

The drawings will be explained below in comparison with a conventional device.

1A and 1B show an example of a device using this type of detector, with A being a top view and B being a side view.

In the figure, 1 is the base, 2 is the motor attached to this base, and 3
4 is a rotating disk attached to the rotating shaft 2' of this motor, and 4 is a detection disk that is attached coaxially with the lower surface of this rotating disk and has a larger diameter than this rotating disk 3, as shown in the figure. A plurality of perforations 4' are provided in a ring shape according to the purpose.

Reference numeral 5 designates a detector block, which has a recess 5' approximately in the center of its side surface, which serves as a passage for the detection object, and the detection plate 4 is disposed in this recess.

On the other hand, a light-emitting element and a light-receiving element, which will be described later, are arranged in the upper and lower parts of the recess 5' facing each other so as to sandwich the detection plate 4, and the detection plate 4 rotates as the motor 2 rotates. By passing the perforation hole 4' between the above-mentioned elements, the rotation status of the motor 2, the status of the perforation hole 4', etc. are converted into electrical signals.

This type of device is applied to rotary encoders, pulse conversion sensors, tachometer sensors, etc.

Note that 6 is a lead wire for taking out the output of the detector block 5.

Conventionally, when attaching a light-emitting element and a light-receiving element, for example, mounting holes are made above and below the recess 5' of the detector block 5 so that the elements can be inserted facing each other, and each element is press-fitted or glued. It was common to install the

However, in this case, it is difficult to match the coaxiality of each element, that is, to match the positional relationship so that the light emitted from the light emitting element exactly reaches the light receiving element (±Q, 1
Even with coaxiality, the detector block 5 is made of synthetic resin and is fixed with adhesive, so it may deform due to the influence of ambient temperature and humidity (deterioration over time). ), which may cause the above-mentioned coaxiality to go out of order, and it is actually extremely difficult to correct this.

In view of this point, the present invention is designed to allow each element to be mounted easily and accurately, and the embodiment shown in FIG. 2 will be described below.

What is shown in FIG. 2A is a partially sectional front view showing the state in which each of the above-mentioned elements is attached to the detector block 5 using the device of the present invention. This is an enlarged view of what it looks like.

In the figure, 7 is a light emitting element such as a light emitting diode, 8 is a light receiving element such as a phototransistor, 9 and 10 are mounting holes for each of these elements provided in the detector block 5, and 11 is attached to the bottom of the light emitting element 7. a printed circuit board, 12 is a light receiving element 8;
The printed circuit boards 13 and 14 attached to the bottom of the circuit board are conductors provided on these circuit boards, and the lead wires of the respective elements are soldered to these conductors.

Reference numerals 15 and 16 denote slits provided above and below the recess, which extend in the vertical direction in the drawing and face each other.

Therefore, the light emitted from the light emitting element 7 passes through the slits 15 and 16 and reaches the light receiving element 8.

FIG. 2B shows a further enlarged view of the vicinity of the light-receiving element 8, and the base of the light-receiving element 8 is provided with a gap 8'. There is.

), this flange fits into a shallow ring-shaped recess 17 provided on the top surface of the detector block 5, and protrudes by a small distance indicated by g.

(Similarly on the light emitting element side) In order to further clarify this state, the portion E in the figure is further enlarged and shown in Figure 0.

With this structure, first tighten the screws S1 to S4 slightly loosely in the state shown in FIG. 2A.
Adjust this by moving the printed circuit board 11, 12 so that the coaxiality of the light receiving element 8 is sufficiently secured, and then tighten the screw wall machine wheel S4 sufficiently, and each element will be adjusted by the protruding dimension g. The printed circuit board 11.12 is in a warped state and a force is generated to press these elements, ensuring that they are fixed in place and their lead wires are also connected to the conductor 13.14. 6 can be easily led out by connecting them by soldering or the like.

Although the device of the present invention has the above-mentioned configuration, it is easy to obtain coaxiality between the light emitting element and the light receiving element during assembly, and deformation of the detector block due to aging is minimal, so even if the coaxiality is out of order, This also has the advantage of being easy to readjust.

[Brief explanation of the drawing]

1A and 1B are top and side views showing an embodiment of a device using a photodetector to which the present invention is applied, and FIG. 2A is a partially sectional front view showing the device of the present invention. , same figure B
, C is an enlarged sectional view of a part thereof. 2...Motor, 4...Detection plate, 5...
...Detector block, 7...Light emitting element, 8
..... Light receiving element, 11.12 ..... Printed circuit board.

Claims (1)

[Scope of utility model registration request] In a photodetector equipped with a light-emitting element and a light-receiving element that are arranged opposite to each other across a detection object passage path, the detector block to which the light-emitting element and the light-receiving element are attached is provided with a mounting hole that allows these elements to be arranged facing each other. A ring-shaped concave hole, which is coaxial with and larger than the attachment hole, is bored on the element insertion side of each of the attachment holes, and the concave hole is connected to the flange portion provided at the base of the light emitting element and the light receiving element. A substrate is attached to the bottom of each element inserted into the mounting hole, and the substrate is set at a depth that allows the element to protrude slightly. An element mounting device for a photodetector, which is fixed to the detector block.