JPS6240779B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a record disc detection device that optically and non-contact detects the presence or absence of a record placed on the turntable of a record player or the size of the record. The objective is to create a record disc that can start playing a record even if it is a transparent record by controlling the operation of the pick-up arm device reliably under control from the start operation. The object of the present invention is to provide a detection device.

Conventional configurations and their problems In general, so-called auto players equipped with a mechanism to control the movement of the pick-up arm require some method to preset the size of the record placed on the turntable, which requires the user to If the setting is incorrect or if a performance is started without placing a record on the turntable, the playback needle may fall onto the turntable and damage the playback needle. Therefore, in order to prevent the above-mentioned malfunction or accidental damage to the playback stylus, we have developed a system that uses transparency of the turntable as a means to optically and non-contact detect the presence or absence of a record on the turntable and the size of the record. An optical record detecting device has been proposed that includes a combination of photoelectric conversion elements (light receivers) arranged under the hole and a light source (emitter) arranged at a position higher than the turntable surface. However, if the record placed on the turntable is transparent, such a record detecting device cannot accurately detect the presence or absence of the record and its size, and it is difficult to accurately detect the presence or size of the record placed on the turntable. The drawback was that it was no longer possible to play records. In other words, when there is no record placed on the turntable, the operation is controlled so that the pick-up arm device does not move based on the detection results, or the operation is controlled so that the pick-up arm device moves up and moves but does not come down. Therefore, when a transparent record is placed on a turntable, the operation is controlled based on the same detection results as these, and the problem is that the record cannot start playing. It was hot.

OBJECTS OF THE INVENTION The present invention solves these conventional drawbacks and makes it possible to reliably detect the presence and size of a record even when the record is transparent.

Structure of the Invention The present invention provides a record player body including a turntable rotatably driven by a turntable shaft, and a rotatably provided record player lid body, and a part of the cover provided inside the record player lid body has the above-mentioned structure. A through hole is provided so as to correspond to the rotation locus of each through hole corresponding to the record size provided on the turntable, and either a light receiver or a light emitter is installed in each of the through holes provided in the cover on the record player lid side. one of the light receivers or the light emitter is arranged correspondingly on the record player main body side, and a through hole provided in the cover is placed on the record player lid side on the turntable. A light shielding member is provided that closes off according to the size of the record placed thereon. In this way, even if the record placed on the turntable is transparent, the existence and size of the record placed on the turntable can be detected in a pseudo manner, and the start operation can be performed. The operation of the pickup arm device can be controlled to ensure reliable performance.

DESCRIPTION OF THE EMBODIMENTS FIGS. 1 and 2 show an embodiment of the record disc detection device of the present invention. In the figures, 1 is a record player body, and a turntable shaft 2 is provided on the top surface of the record player body, which is rotatably driven. It has a turntable 3. Reference numeral 4 denotes a record player lid rotatably connected to the record player main body 1 by a hinge 5 at the rear of the record player main body 1;
It has a pick-up arm device 7 for playing a record 6 placed thereon. In this pick-up arm device 7, a tone arm 9 having a cartridge 8 at its tip is swingably attached to a tone arm base 11 that moves on a guide rail 10.
A movable rod 12 coupled to the movable rod 12 is adapted to be moved by a main body of a driving device such as a motor (not shown). The main body of the driving device is covered with a cover 13 provided inside the record player lid 4, and its operation is controlled by a record detecting device which is a part of the main body of the device.
The record detecting device is the turntable 3.
Through holes 14a, 14b, 14c for detecting record discs of various sizes (30cm, 25cm, 17cm)
The light sources 15a, 15b, 15c arranged below, the photoelectric conversion elements 17a, 17b, 17c arranged below the through holes 16a, 16b, 16c of the cover 13 to which the light sources 15a, 15b, 15c correspond, and the through holes It has light shielding members 18a, 18b, 18c for blocking 16a, 16b, 16c. The through holes 16a, 16b, 16c of the cover 13 are the through holes 14a, 14b provided in the turntable 3,
The through holes 16a, 16b, 16c are provided so as to correspond to the respective rotation loci of the holes 14c.
Photoelectric conversion elements 17a, 17b, 17 arranged below
c and the through holes 14a, 14 of the turntable section.
Light sources 15a, 15b, 1 arranged below b, 14c
5c and are in a fixed state and facing each other. That is, the photoelectric conversion elements 17a, 17
b, 17c and the light sources 15a, 15b, 15c are provided on the record player lid 4 and the record player main body 1 side, respectively, so as to correspond to the through holes 16a, 16b, 16c. The light shielding members 18a, 18b, 18c are made of rubber, for example, and the protrusions are connected to the through holes 16a, 16b,
It is designed to be held by fitting it into 16c.

The cover 13 also includes the light sources 15a and 1.
5b, 15c and the photoelectric conversion elements 17a, 17
Through-holes 19a, 19b, 19c for temporarily holding the light shielding members 18a, 18b, 18c are provided at locations that do not correspond to the light shielding members 18a, 18b, 18c.

In a record disc detection device having such a configuration, when an opaque record disc 6 is normally placed on the turntable 3, the light shielding members 18a, 18
b, 18c are through holes 19a, 19b, 1 for temporary holding.
9c, and the light sources 15a, 15b, 1
5c and the photoelectric conversion elements 17a, 17b, and 17c are shielded from light according to the size of the opaque record 6. In other words, if the opaque record 6 is 30 cm long, the existence and size of the 30 cm record 6 is detected by blocking all light, and the opaque record 6 is 25 cm long. In this case, the presence or absence of a 25cm record 6 and its size are detected by unblocking the outer one and blocking the inner two, and if the opaque record 6 is 17cm, then The presence or absence and size of the 17 cm record disc 6 can be detected by removing the light shielding of the outer two and shielding the inner one.

Therefore, the operation of the pickup arm device 7 can be controlled to ensure reliable record performance from the start operation.

On the other hand, when a transparent record 6 is placed on the turntable 3, the light cannot be blocked by the record 6. It will be detected. Therefore, in such a case, light blocking members 18a, 18b, 18c are inserted into the through holes 16a, 16b, 16c of the cover 13 according to the size of the transparent record 6 placed on the turntable 3. It is created that a pseudo-opaque record is placed on it. In other words, in the case of a 30 cm transparent record 6, the through holes 16a, 16b, 16
Insert the light shielding members 18a, 18b, 18c into all holes 18a, 18b, 18c in the case of a 25cm transparent record 6, insert the light shielding members 18b, 18c into the through holes 16b, 16c, and in the case of a 17cm transparent record 6. By inserting the light shielding member 18c only into the through hole 16c, it is possible to detect the presence or absence of the record 6 and its size even if it is a transparent record in the same way as an opaque record. The operation of the pick-up tape device 7 can be controlled so that playback of the record can be reliably started from the operation.

Note that in the above embodiment, the light shielding members 18a, 18
Although the case where b and 18c are single items has been described, they may be formed into a belt-like connecting part 20 with the respective protrusions integrated, as shown in FIG. In this case, the through hole 1 of the cover 13
It is necessary to provide at least two other play holes 21a, 21b in the alignment direction of 6a, 16b, 16c, and three play holes 21a, 21b.
If 21b and 21c are provided, these play holes 21
a, 21b, and 21c can be used as through holes for temporary holding.

Further, in the above embodiment, the light shielding members 18a, 18
b, 18c are the through holes 16a, 16b of the cover 13,
16c, the knob 32 provided on the light shielding plate 31 is inserted into the relief hole 3 as shown in
3, and the light shielding plate 31 may be slid by operating the knob 33. In this case, the light shielding plate 31 is formed of a plastic plate, and has at least four through holes 34a, 34.
b, 34c, 34d through holes 16a, 16b, 16
It is necessary to provide one corresponding to the pitch of c.

Further, in the above embodiment, the light source was arranged under the through hole of the turntable 3 of the record player body 1, and the photoelectric conversion element was arranged under the through hole of the cover 13 of the record player lid body 4. The container may be replaced between the record player main body 1 and the record player lid 4.

Effects of the Invention As described above, according to the present invention, a record player body including a turntable rotatably driven by a turntable shaft is rotatably provided with a record player lid, and the inside of the record player lid is A through hole is provided in a part of the provided cover so as to correspond to the rotation locus of each through hole corresponding to the record size provided on the turntable, and each of the through holes provided in the cover is provided on the cover side of the record player. either one of the light receivers or the light emitters is arranged correspondingly on the record player body side, and the other of the light receivers or the light emitters is arranged correspondingly on the record player body side, and the cover is provided on the record player lid side. Since a light shielding member is provided that closes the transparent hole according to the size of the record placed on the turntable, even if the record placed on the turntable is transparent, it will not cause false alarms. It is possible to detect the presence or absence of a record placed on the disc and to detect its size, thereby controlling the operation of the pick-up arm device to ensure reliable performance from the start operation.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view of a record player equipped with a record detecting device of the present invention, FIG. 2 is an enlarged sectional view of the main part of the device, and FIGS. 3 and 4 are views of the record player of the present invention. FIG. 7 is a main part configuration diagram showing another embodiment. DESCRIPTION OF SYMBOLS 1... Record player main body, 2... Turntable shaft, 3... Turntable, 4... Record player lid, 5... Hinge, 7... Pick up arm device, 13... Cover, 14a, 14
b, 14c...through hole, 15a, 15b, 15c...
...Light emitter (light source), 16a, 16b, 16c...
Through hole, 17a, 17b, 17c... Light receiver (photoelectric conversion element) 18a, 18b, 18c... Light shielding member, 19a, 19b, 19c... Temporary holding hole, 2
0... Connecting parts, 21a, 21b, 21c... Escape hole, 31... Light shielding plate, 34a, 34b, 34
c, 34d...through hole.

Claims (1)

[Claims] 1. A record player body including a turntable rotationally driven by a turntable shaft is rotatably provided with a record player lid, and when the record player lid is closed, a cover provided inside the record player body is rotatably provided. A plurality of through holes are provided in a part of the turntable so as to correspond to the rotation locus of each through hole corresponding to the record size, and each hole is provided on the cover side of the record player so as to correspond to the rotation locus of each through hole corresponding to the record size. and arranging one of the light receiver and the light emitter, and arranging the other of the light receiver and the light emitter corresponding to each of the through holes provided in the cover on the record player main body side, and the record player. A record disc detection device comprising a light shielding member provided on the lid body side for closing a through hole provided in the cover according to the size of the record disc placed on the turntable. 2. The light shielding member is formed into a band shape and has a protrusion that is fitted into each of the through holes provided in the cover, and the cover is provided with at least two other relief holes in the direction in which each of the through holes is lined up. A record disc detection device according to claim 1, characterized in that: 3. Claims characterized in that the light shielding member is formed into a plate shape and has holes corresponding to the respective through holes provided in the cover, and is provided so as to be slidable with respect to the cover. The record disc detection device according to item 1.