JPH0222837Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a rotating disc holding mechanism for stably holding discs such as vinyl records, magnetic discs, and optical discs in record players, floppy disc drive devices, etc. .

(Prior art) In record players or floppy disk drive devices that use discs such as records, magnetic discs, optical discs, etc. as recording media, the turntable on which the discs are placed and rotated is particularly sensitive to the outside diameter of the discs. For smaller discs, in order to eliminate instability of the disc due to the pickup or detection head coming into contact with the disc, a presser block is provided near the center of the disc, facing the turntable, and this presser block and the turntable The disc is held between the table and the presser block is rotated together with the turntable and the disc.

FIG. 1 is a partial cross-sectional view of a conventional disc holding mechanism, in which 1 is a cabinet, 2 is a turntable, 2a is its rotating shaft, 4 is a holding frame, 5 is a shaft, 14 is a presser block, and 16 and 17 are radial bearings for rotatably supporting the presser block 14. That is, the presser block 14 is rotatably attached to the free end of the presser frame 4 by the shaft 5 via radial bearings 16 and 17, and the presser frame 4 is opened diagonally upward using the opening/closing fulcrum 3 as a fulcrum. Place a disc D such as a record on the top surface of the turntable 2 in this state, then fold down the presser frame 4 and press the presser block 14.
The disk D is pressed downward by its own weight. As a result, the disk D is securely brought into close contact with the turntable 2 even in response to an external force P applied when a pickup or a detection head or the like comes into contact with the disk D, so that it does not flap or come off.

Also, because the turntable rotation center S and the presser side rotation center S' do not necessarily match due to assembly errors, the outer diameter ds of the shaft 5 is the same as the bearing 1.
The inner diameter dimension is selected to be smaller than the inner diameter dimension dB of 6 and 17, so as to absorb the deviation of the respective rotation centers. That is, if the rotation center S' on the presser side is shifted when the disk D starts rotating, the circumferential speed at the contact surface between the presser block 14 and the disk D will not be uniform, so a restoring force will act, and the center of the presser block 14 will be shifted. It slides to a point where it coincides, and becomes stable at that point.

Therefore, the radial bearing 1 provided to rotatably support the presser block 14
6 and 17 receive a slight radial load (load when the presser block 14 skids sideways) when rotation starts, and also receive a weak thrust load via the presser frame 4 and shaft 5 by the spring 3a of the opening/closing fulcrum 3. It was extremely wasteful to install radial bearings in such locations.

That is, this type of equipment (record player,
In the case of floppy disc drive devices, etc.), the rotation accuracy of the disk D significantly affects the reproduced or detected signals, so rotating parts such as bearings are required to have extremely low friction, and these requirements must be met. This is because commercially available radial bearings are very expensive. Therefore, the conventional example has the drawback of increasing the cost of the entire device, and it has been desired to provide an inexpensive and high-performance rotary disk holding mechanism.

(Purpose of the invention) The present invention was proposed in view of the above points, and its purpose is to achieve low cost, high precision, and easy assembly by using loose ball bearings in the rotating part. The purpose is to provide an easy rotating disk holding mechanism.

(Structure of the invention) Hereinafter, the invention will be described in detail with reference to drawings showing embodiments.

FIG. 2 shows the structure of an embodiment of the rotating disk holding mechanism according to the present invention, and shows a side view of the device partially in section. In the figure, a turntable 2 is provided on the upper surface of one end of a cabinet 1 on which a disk D such as a record, magnetic disk, or optical disk is placed and rotated.
Inside the cabinet 1, a drive unit (not shown) such as a motor is provided.

On the other hand, an opening/closing fulcrum part 3 is provided at the other end of the cabinet 1, and one end of a presser frame 4 having an L-shaped cross section is rotatably attached to a support shaft 3b. I'm starting to be able to do it. Further, a spring 3a is provided at the opening/closing fulcrum portion 3, and urges the presser frame 4.

Here, in the present invention, the presser frame 4
It includes a shaft disposed below the free end portion substantially coaxially with the rotation axis of the turntable 2, and a presser block rotatably attached to the shaft via a bearing.

That is, in this embodiment, the presser frame 4
A substantially cylindrical presser block 1 is mounted below the free end of the turntable 2 via a bearing (bearing portion) 20 by a shaft 5 located coaxially with the rotation axis 2a of the turntable 2.
4 is rotatably attached, and the weight of this presser block 14 causes the disc D to come into close contact with the turntable 2. In addition, disk D
The pressing method is not limited to using the weight of the presser block 14; for example, it is also possible to provide a spring (not shown) coaxially with the shaft 5 and press it by the repulsive force between it and the presser frame 4. In this case, the device can be installed in any position.

Further, in the present invention, the bearing 20
is filled between an inner support body disposed around the shaft 5 with a slight gap between them, an outer support body disposed on the presser block 14 side, and these inner and outer support bodies. It is characterized by being made up of multiple balls supported from left and right.

That is, the bearing 20 according to the present invention is constituted by a so-called loose ball type bearing, and this loose ball type bearing is arranged around the shaft 5 with a slight gap, and the axis of the outer peripheral surface is A substantially cylindrical inner support 9 with a stepped portion 9a formed in the central portion thereof, and a ring-shaped outer support which is inserted into the inner circumferential surface of the presser block 14 and has a substantially L-shaped peripheral cross section. It consists of rotary support rings 12 and 13 and a plurality of balls 10 and 11 filled between the inner support body 9 and the rotary support rings 12 and 13. In this loose ball type bearing, the upper, lower, left and right sides of the outer peripheral surfaces of the balls 10 and 11 are aligned with the outer peripheral surface of the cylindrical portion of the inner support body 9, the upper and lower surfaces of the stepped portion 9a, and the inner surfaces of the rotation support rings 12 and 13. The balls 10 and 11 are supported in contact with each other, and have the advantage that they can withstand sufficient radial load and thrust load, rotate smoothly, and can be manufactured at low cost.

As an assembly method, for example, the presser block 14
Turn the top and bottom in the opposite direction to that shown in the figure, and after inserting one rotation support ring 12, rotate the ball 10 in the circumferential direction.
By arranging the balls 11 in a row, inserting the inner support 9 inside the balls 11, further arranging the balls 11 in one row in the circumferential direction along the step 9a of the inner support 9, and finally inserting the other rotation support ring 13. In this way, assembly from only one direction is possible. Also, the stop ring 15, which has a part cut out in the circumferential direction, is compressed in the radial direction and inserted into the inner wall surface of the presser block 14,
By engaging the groove 14a provided on the inner wall surface, the bearing 20 can be prevented from coming off.
There is no need to worry about the bearing 20 loosening and falling during the process of assembling other members or using the device. Note that the stop ring 15 may be of a screw-in type.

The bearing 20 assembled integrally with the presser block 14 as described above is held at its lower surface by the flange portion 5b of the shaft 5 passing through the inner support 9, and the threaded portion 5a of the shaft 5 is inserted through the ring 6. By screwing into the lower surface of the free end of the presser frame 4, the presser block 14 is rotatably held.

Here, as mentioned above, in order to maintain a slight gap between the shaft 5 and the inner support 9, the outer diameter ds of the shaft 5 is selected to be slightly smaller than the inner diameter dB of the inner support 9. As the presser block 14 follows and rotates together with the turntable 2, it absorbs the deviation between the turntable rotation center S and the presser side rotation center S' within the range of the gap, and the respective centers coincide. will be automatically corrected. Note that 7 and 8 indicate plastic washers, which are provided as cushions during transportation and to make it easier to slip when the presser block 14 moves to absorb misalignment at the beginning of rotation of the disc D. , the upper plastic washer 7 is responsible for contacting said ring 6.

However, in operation, the presser frame 4
The disk D is placed on the turntable 2 with the opening/closing fulcrum part 3 being used as a fulcrum and opened upward, and then the presser frame 4 is brought down and the disk D is brought into close contact with the turntable 2 by the weight of the presser block 14.
Next, when applying a rotational force to the turntable 2, if the turntable rotation center and the presser side rotation center S' are misaligned due to assembly error or looseness of the mounting part, the presser block 14 moves these centers S,
The radial load generated at this time is received by the rolling contact between the outer peripheral surface of the inner support member 9 and the inner peripheral surfaces of the rotary support rings 12 and 13 by the balls 10 and 11. It will last. Further, the thrust load applied to the shaft 5 via the presser frame 4 by the spring 3a is applied to the stepped portion 9a of the inner support 9 and the rotary support ring 1.
The balls 10 and 11 are held in rolling contact with the inner bottom surfaces of the balls 2 and 13. Note that the radial load and thrust load at this time are sufficiently small.
Sufficient yield strength can be obtained even with a simple configuration as in the present application, and since the balls 10 and 11 are in complete rolling contact, the rotation is extremely smooth, and the rotation of the disk D is hardly affected. do not have.

(Effects of the invention) As described above, in the rotary disk holding mechanism of the present invention, the holding frame is attached to one end of the cabinet equipped with the turntable so as to be openable and closable, and the holding frame is attached below the free end of the holding frame. In a rotating disk holding mechanism that rotatably holds a disk placed on the turntable when the holding frame is closed, the rotating disk holding mechanism is arranged substantially coaxially with the rotation axis of the turntable below the free end of the holding frame. a presser block rotatably attached to the shaft via a bearing;
It consists of an inner support body disposed holding the presser block, an outer support body disposed on the presser block side, and a plurality of balls filled between these inner and outer support bodies and supported from the top, bottom, right and left directions. As a result, it is possible to obtain a rotating disk holding mechanism that is inexpensive, highly accurate, and easy to assemble. Also,
When the presser block is driven and rotates together with the turntable, the center of rotation of the turntable and presser side is automatically corrected to match within the range of 〓 between the shaft and the inner support, ensuring stable rotation of the disk. be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional presser mechanism, and FIG. 2 is a block diagram showing an embodiment of the present invention. 1...cabinet, 2...turntable,
3... Opening/closing fulcrum part, 4... Presser frame, 5...
Shaft, 6... Ring, 7, 8... Plastic wedge, 9... Inner support, 10, 11...
Balls, 12, 13...Rotating support ring, 14...
...Presser block, 15...Stop spring, D...
…disk.

Claims (1)

[Claims for Utility Model Registration] A presser frame is attached to one end of a cabinet equipped with a turntable so as to be openable and closable, and a presser frame is placed below the free end of the presser frame so that the presser frame rests on the turntable when the presser frame is closed. A rotary disk holding mechanism that rotatably holds a placed disk includes a shaft disposed below the free end of the holding frame approximately coaxially with the rotation axis of the turntable, and a shaft rotatable to the shaft via a bearing. and a presser block attached to the shaft, and the bearing includes an inner support disposed around the shaft with a slight gap between them, an outer support disposed on the presser block side, and a presser block attached to the shaft. and a plurality of balls filled between the outer support body and supported from the top, bottom, right and left directions, and as the presser block is driven and rotated together with the turntable, it moves between the turntable rotation center and the presser block within the range of the above distance. A rotating disk holding mechanism characterized by automatic correction so that the side rotation center coincides with the rotation center.