JPS6343602Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a record disc suction device that integrally suctions and fixes a record disc to a turntable side during record playing.

It is well known that cross-modulation distortion occurs due to the warping of a record, and that rumble noise is generated when minute vibrations are induced in the record due to sound pressure radiated from speakers, etc. There is. In order to solve this problem, the present applicant previously proposed a device for fixing a record by the suction effect of negative pressure (see Japanese Patent Application No. 80,645/1983). Briefly explaining this device, it has a disc body that is removably interposed between a record to be played and a turntable. An air chamber is provided. On the other hand, on the surface side of this disk body, there is an annular outer layer that is in close contact with the outer circumferential edge (group guard) of the record and the inner circumferential edge near the label section, forming an airtight space between them. A seal and an inner seal are provided. This space and the air chamber are communicated with each other via an intake port, and by reducing the pressure in the air chamber with a vacuum pump or the like, the record placed on the disc body is It is firmly adsorbed and fixed onto the disc body. According to actual measurements, the adsorption force is quite strong, about 250 kg, and as a result, the record is fixed almost integrally on the disc body with the warp corrected. In order to release the record from above the disc, the release valve is opened to open the air chamber to the atmosphere, but in this case, the disc and the record are in close contact with each other. ,
Since it is difficult for air to quickly flow into the gap between the two, the release operation tends to be slow. In this regard, it is known that ventilation grooves are formed on the surface of the disc body in relation to the intake port communicating with the air chamber and extend in the radial direction from the intake port so that air can quickly flow in. However, according to this, when a record is picked up, the record may be damaged by burrs in the ventilation groove, and the record may be deformed by the ventilation groove itself, which may affect the sound quality and handling. It was not favorable in terms of

Therefore, the object of this invention is to provide a record disc suction device that can quickly and smoothly release a record disc without the above-mentioned drawbacks.

Hereinafter, embodiments of this invention will be described with reference to the accompanying drawings.

This record disc suction device 1 has a disc body 3 having approximately the same diameter as a turntable 2 of a record reproducing device and is removably placed thereon. This disk body 3 has a center hole 5 through which the center spindle 4 is inserted, an air chamber 6 airtightly formed in the center surrounding the center hole 5, and an air chamber 6 extending toward the air chamber 6 from the outer peripheral end wall. A pair of through holes 7 are provided which are bored from opposite directions. In this case, although not shown in the drawings, the air chamber 6 is actually formed by assembling a pair of plate members from above and below into the central opening of the donut-shaped substrate.
Furthermore, a suction valve 8 and a release valve 9 are installed in the outer peripheral end wall openings of the through holes 7, 7, respectively. And the through holes 7, 7 are the passage 1
It communicates with the air chamber 6 via 0. An annular groove 11 is formed on the outer periphery of the air chamber 6 of the disc body 3, and an inner plate having a thin flange 12 formed in the annular groove 11 so as to extend inward at a slight upward angle. A seal 13 is fitted. This inner seal 13 is made of a flexible material such as neoprene rubber, and is made of a flexible material such as neoprene rubber.
(See Figure 3) is designed to come into close contact with the non-recording surface adjacent to the label section. Further, on the outer periphery of the inner seal 13, a plurality of (four in this embodiment) vertically extending notch grooves 15 are formed which communicate with the air chamber 6 via the passage 10. Furthermore, a damping plate 16 made of synthetic rubber or the like is attached to a portion inside the inner seal 13 on which the label section of the record disc 14 is placed. On the other hand, an annular outer seal 18 is provided on the outer periphery of the disk body 3 and has a thin flange 17 formed to extend toward the outer periphery at a slight upward angle. This outer seal 1
8 is made of a flexible material such as neoprene rubber, similar to the inner seal 13, and is made of a flexible material such as neoprene rubber.
It is designed to fit closely to the outer periphery including the group guard. In this invention, an open-cell soft material is formed between the inner seal 13 and the outer seal 18 in a portion corresponding to the sound groove portion of the record 14 to be placed, that is, on the upper surface of the disc body 3. A sheet 19 is attached. Here, open cell property means a state in which air bubbles are in communication with each other and ventilation is achieved, and for example, polyurethane foam is suitable for such a soft sheet 19, and it is also made of polyurethane foam, which is better than the material of the record 14. Preferably, it is soft.

In the above configuration, the disc body 3 is set on the turntable 2, and the record disc 14 is further placed on the disc body 3. And release valve 9
is closed, a suction pump (not shown) is connected to the suction valve 8, and vacuum suction is performed.The air interposed between the record disc 14 and the soft sheet 19 flows through the notch groove 15, the passage 10, and the through hole 7. The air is discharged together with the air in the air chamber 6. As a result, the internal space of the disc body 3 is brought into a reduced pressure state, and the record disc 14 is firmly fixed on the disc body 3 by suction. In addition, during this adsorption operation,
In particular, the air that is difficult to take in from the outer seal 17 side is taken in through the sheet 19, so that the suction operation is made more quickly and almost completely, and the air between the outer seal 17 and the record 14 is taken in. Even if dust particles are caught, the dust particles will be buried in the sheet 19 side.
There is almost no risk that the sound groove portion will be damaged.

Thereafter, the suction pump is removed and the turntable 2 is turned to enter the playing state. At the end of a performance, etc., the record 14 is removed by opening the release valve 9 and allowing external air to flow into the internal space of the disc body 3. in this case,
The record disc 14 is in close contact with the soft sheet 19, but since the soft sheet 19 is open-celled, the air flowing in from the notch groove 15 passes through the soft sheet 19 as shown by the arrow in FIG. It flows in and diffuses, and the adsorption state is quickly released. moreover,
According to this invention, the record disc 14 has a sheet 19
Since the sound grooves are protected by the sound grooves, a ventilation hole 20 is drilled from the top surface of the disc body 3 toward the through hole 7 as shown by the imaginary line in the figure, without considering damage to the sound groove portion. It is also possible to release the adsorption more quickly.

Note that this invention is not limited to the embodiments described above. For example, if the damping plate 16 is configured as a type of sealing means and the label portion of the record disc 14 is kept airtight, the inner It is also possible to omit the seal 13. Moreover, this record disc suction device can also be formed integrally with the turntable of a record player. Furthermore, this idea involves placing an air intake tank case called a suction adapter on the label section of the record, and connecting the center spindle through the airtight hole between the record and the disk. The present invention can also be applied to a type of record suction device that sucks air from a space.

As is clear from the description of the embodiments described above, according to this invention, an open-cell soft sheet is attached to the upper surface of the disc body, so the record is attached to the disc body through this soft sheet. Since the soft sheet allows good air circulation, both suction and release can be done quickly. Furthermore, when the record is strongly suctioned and fixed, even if dust particles are caught, the dust particles will be buried in the soft sheet side, and there is little risk of damage to the sound grooves. do not have. Furthermore, since the record is evenly pressed onto the soft sheet, there will be no local deformation, and better sound quality can be expected.

[Brief explanation of the drawing]

All figures show examples of this invention.
FIG. 1 is a sectional view, FIG. 2 is a plan view, and FIG. 3 is a partially enlarged sectional view. In the figure, 1 is a record adsorption device, 2 is a turntable, 3 is a disc body, 4 is a center spindle, and 5
is a center hole, 6 is an air chamber, 7 is a through hole, 8 is a suction valve, 9 is a release valve, 10 is a passage,
13 is the inner seal, 14 is the record, 15
18 is an outer seal, and 19 is a soft sheet.

Claims (1)

[Scope of claim for utility model registration] (1) Rotatably attached to a record playback device,
Shielding means including a disc body that rotates together with the record disc placed thereon, and an outer seal that tightly adheres to the outer periphery of the record disc and forms an airtight space between the record disc and the disc body. A device for suctioning and fixing the record onto the disk body by suctioning the air in the space with a vacuum pump or the like through a check valve, which corresponds to the sound groove portion of the record. A record adsorption device characterized in that an open-cell soft sheet is provided on the surface of the disc body. (2) The record disc suction device according to claim (1), wherein the soft sheet is made of a material softer than the record disc.