JPS6323765Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an optical sensor in a track interval detection device for a record disc.

Detection of track intervals on a record in an automatic performance device of a record player is performed by an optical sensor using a light-emitting element and a light-receiving element.As shown in FIG. A light-emitting element 5 and a light-receiving element 6 are respectively disposed in the housing parts 3 and 4 which face each other with the housing parts 3 and 4 interposed therebetween. , 10 are extended downward to form partition walls 11, 12, respectively. In the figure, 13 is a record, and the arrow indicates the direction of movement of the optical sensor.

In this conventional structure, the slits 7 and 8 constrict the light beam to improve detection accuracy, but even if the slit width is narrowed below a certain width, the detection accuracy does not increase any further and the light receiving output only decreases. Therefore, there was a natural limit to detection accuracy. Further, it is difficult to adjust the mounting angle and mounting position of the light emitting element 5 and the light receiving element 6 so as to maximize the light receiving sensitivity, and the adjustment structure is also complicated.

Further, there is a device in which a condensing lens is arranged in front of the light emitting element 5 and the light receiving element 6, but this requires an adjustment mechanism such as focus adjustment, and has the disadvantage of being structurally complicated.

The present invention is an improvement over such conventional drawbacks, and as explained in FIG. It has a structure in which the tips protrude from the tips of the partition walls 11 and 12 which are extensions of the outer walls 9 and 10 of the storage section, and more preferably, the partition walls 14 are attached so as to be movable left and right (as shown in the figure). , the structure is such that the mounting angle can be changed.

According to the above structure, in the space formed by the partition walls 11 and 12, the tip end of the partition wall 1
Partition wall 14 with a triangular cross section protruding from 1 and 12
As a result, the optical path from the light emitting element 5 and the optical path from the light receiving element 6 are blocked, and the light from the light emitting element 5 travels along the inclined surface of the partition wall 14 having a triangular cross section, and the light path from the light emitting element 5 is propagated along the slope of the partition wall 14 having a triangular cross section. The light reflected by the partition wall 1
4 and reaches the light receiving element 6. In other words, the optical path from the light-emitting element 5 to the light-receiving element 6 is unified, and mutual interference of light is reduced.As shown by the solid line a in FIG. 3, although the light reception output is reduced, the detection accuracy between songs is improved. It has a significantly improved performance and is also structurally simple.

FIG. 4 shows the actual measurement results of one example. In this embodiment, the distance L between the record and the slit opening is
7.5mm, height of partition wall h is 5.2mm, diameter of light emitting side is 2
mm circular slit, and the receiving side is a 2 mm x 0.8 mm rectangular slit.
This is the actual measured value of the received light output when detecting a mm-wide track interval. In the figure, the dotted line indicates a conventional example without a partition wall.
Because the relative mounting positions of the light-emitting element and the light-receiving element are insufficiently adjusted, the (peak) light-receiving output does not correspond to the intervals between songs. On the other hand, according to this embodiment, the (peak) of the received light output corresponds well to the intervals between songs.

As described above, in the optical sensor using the light-emitting element 5 and the light-receiving element 6, the optical path from the light-emitting element 5 to the light-receiving element 6 is unified by the partition wall 14. It has the practical advantage of significantly improving the detection accuracy between the two and having a significantly simple structure.

[Brief explanation of the drawing]

Figure 1 shows the structure of a conventional optical sensor, Figure 2 shows the structure of the optical sensor of the present invention, and Figure 3 shows the structure of the optical sensor of the present invention.
The figure is a characteristic diagram of the same, and FIG. 4 is an actual measured characteristic diagram of one example. 1 is the holder, 2 is the center wall, 3 and 4 are the storage parts,
5 is a light emitting element, 6 is a light receiving element, 7 and 8 are slits, 9 and 10 are outer walls of the storage section, 11 and 12 are partition walls,
14 is a partition wall.

Claims (1)

[Scope of utility model registration request] A light emitting element 5 and a light receiving element 6 are arranged in storage parts 3 and 4 facing each other across the center wall 2 of the holder 1, and slits 7 and 8 are arranged in the lower walls of the storage parts 3 and 4, respectively.
are provided respectively, and the outer walls 9 and 10 of the storage portion are provided.
In the structure in which the partition walls 11 and 12 are formed by extending the partition walls 11 and 12 downward, a wedge-shaped partition wall 14 having a triangular cross section is provided at the lower end of the center wall 2, and the tip of the partition wall 14 is connected to the partition walls 11 and 12, respectively. An optical sensor characterized by protruding from the tip of 12.