JPS6331153Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoelectric detection device for optically detecting perforations or marks on media such as tape or paper.

As a photoelectric detection device, a device for detecting perforations on a format control tape (hereinafter referred to as FT) used in a printing device such as a line printer shown in FIG. 1 will be explained as an example.

Each of the sensor cases 1 and 2 has a built-in light receiving element and a light emitting element, and detects the perforation on the FT 4 sent in the direction of arrow A by the sprocket 3. F.T.
4 runs at a speed of several inches to several tens of inches/second, and is often used to constantly run while the printing device is in operation.
FT4 is made of materials such as Mylar with a sanderch structure made of paper, or paper only, but it tends to generate dust such as paper powder when running. These optical sensors have a light-receiving element and a light-emitting element housed in sensor cases 1 and 2, which are colored black or the like, so that no light passes through except for the optical axis, and a small detection hole is made in the optical axis to prevent the dust from entering the area. Generally, a transparent flat plate such as a glass sheet is attached with adhesive to the tape running surface to prevent false detection by entering through the detection hole.

As shown in FIG. 2, the sensor cases 1 and 2 are each provided with a glass sheet mounting groove 6 with a depth slightly larger than the thickness of the glass sheet 5 in the glass sheet mounting portion so as not to interfere with the running of the FT 4. There is.

Furthermore, as shown in FIG. 3, a narrow groove 7 for applying an adhesive 10 is provided in the mounting groove 6 around the group of detection holes 8.

At a portion of the boundary 9 between the glass sheet 5 and the glass sheet mounting groove 6 that is perpendicular to the running direction of the FT 4,
The dust easily enters the glass sheet 5, and if vibrations such as those generated during printing are added to this, the dust will enter the inside of the glass sheet 5, so the adhesive 10 is applied around the narrow groove 7 in a manner that seals the dust. There is a need.

However, it is difficult to completely confine the applied adhesive 10 inside the narrow groove 7, and when the glass sheet 5 is attached after applying the adhesive 10, the adhesive 10 is inserted into the detection hole as shown in FIG. 8 and not only lowers the detection output, but also
There was a risk of false detection.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to improve the functionality of this type of device.

In this invention, the adhesive for fixing a transparent flat plate such as a glass sheet plays the role of sealing dust, and at the same time, the shape of the part that fixes the transparent flat plate is changed to prevent the adhesive from entering the detection hole. Even if the adhesive were to protrude from the application groove, it would not reach the detection hole.

FIG. 5 shows one implementation of the present invention, in which a plurality of detection holes 8 are provided between the detection hole 8 and the adhesive application groove 7.
A puffer groove 11 is provided extending along. The buffer groove 11 prevents the adhesive 10 flowing out from the coating groove 7 from flowing into the detection hole 8.

In the above embodiment, the buffer grooves 11 are provided on both sides of the detection hole 8, but the buffer grooves 11 are provided on both sides of the detection hole 8.
Of course, it is also possible to provide the adhesive on the sides, and in this case, it is possible to more completely prevent the adhesive from flowing in. Further, although the buffer groove 11 is a long groove along the detection hole 8, a large number of small grooves of arbitrary shapes may be provided and these may be arranged in a staggered manner.

As described above, according to the present invention, it is possible to almost completely prevent the adhesive from flowing into the detection hole, thereby preventing a decrease in the detection force level and the detection, and improving the detection accuracy.

[Brief explanation of drawings]

Figure 1 is a front view of an FT reader showing an example of a photoelectric detection device, and Figure 2 is a conventional storage (sensor).
FIG. 3 is a sectional view taken along the line -- in FIG. 2, FIG. 4 is an explanatory sectional view, and FIG. 5 is a sectional view showing an embodiment of the device of the present invention. In the figure, 1 and 2 are sensor cases, 5 is a glass sheet, 6 is a glass sheet mounting groove, 7 is an adhesive application groove, 8 is a detection hole, 9 is a boundary, 10 is an adhesive, 11 is a buffer groove, 12 is a light emitting element (light receiving element).

Claims (1)

[Claims for Utility Model Registration] At least one light-emitting element and/or light-receiving element is accommodated, and a detection hole is provided at a position facing the light-emitting element and/or light-receiving element, and a detection hole is provided on at least both sides of the detection hole. a storage case having an adhesive application groove; and a transparent flat plate adhesively fixed to the storage case so as to cover the upper surface of the detection hole; What is claimed is: 1. A photoelectric detection device, comprising: a buffer groove provided between the detection hole and the adhesive application groove to prevent adhesive from flowing into the detection hole;