JP2528084B2 - Turntable - Google Patents

Description

The present invention relates to a turntable in which vibration propagating from a turntable to a record board is reduced.

In a record player in which a turntable is directly driven by a motor, there is a problem that vibration accompanying the rotation of the motor generally propagates to the record board via the turntable and adversely affects sound quality of reproduced sound such as noise. Therefore, the turntable and the motor are separately arranged and separated from each other, and the both are connected by a thread or a belt,
Conventionally, a turntable has been used that suppresses the propagation of vibration to the turntable when the motor rotates.
However, in this type of turntable,
In order to further improve the sound quality of the reproduced sound, it is desirable to further suppress the propagation of vibration from the turntable to the record board.

The present invention has been made in view of this point, and it is an object of the present invention to reduce vibration propagating to a record board via a turntable.

In order to achieve the above object, the first invention is that the rotational vibration of the motor propagating to the record board through the turntable is reduced as the substantial contact area between the turntable and the record board is reduced. Focusing on the two points that vibration is less likely to propagate as the density of air, which is the medium, is lower, that is, the lower the pressure is, the rotating shaft (4) having the passage (4a) formed therein.
And a boss (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted, and a recess (7a) opening upward around the boss (7d). The turntable base (7) thus formed is formed separately from the turntable base (7), and the upper surfaces of the recess outer wall (7e) and the boss (7d) of the turntable base (7) are formed. A turntable upper plate (8) which is placed in contact with and covers the concave portion (7a) to form a closed hollow portion (9), and a passage of the rotary shaft (4) in the closed hollow portion (9) ( 4a) through a vacuum pump connected, by the operation of the vacuum pump,
The turntable is characterized in that the hollow portion (9) is set to an extremely low pressure.

A second aspect of the invention is a boss portion having a rotary shaft (4) having a passage (4a) bored therein and a vertical hole (7f) into which the rotary shaft (4) is fitted and which is centered. (7d) and a turntable base (7) in which a recess (7a) opening upward is formed around the boss (7d), and the turntable base (7) is formed separately from the turntable base (7). A turntable upper plate which is mounted on the upper surface of the recess outer wall (7e) of the turntable base (7) and the upper surface of the boss (7d) so as to cover the recess (7a) to form a closed hollow portion (9). (8), a vacuum pump connected to the closed hollow portion (9) via the passage (4a) of the rotary shaft (4), the bottom surface of the turntable base (7), and the turntable (6). The air pressure formed in the space (25) between the upper surface of the cabinet (2) supporting the And a floating support mechanism for floating support Buru (6), by operation of the vacuum pump, there is provided a turntable, characterized in that the said hollow portion (9) to the pole to the low pressure.

A third aspect of the invention is a boss portion having a rotary shaft (4) having a passage (4a) and a vertical hole (7f) into which the rotary shaft (4) is fitted. (7d) and a turntable base (7) in which a concave portion opening upward is formed around the boss portion (7d), a concave outer wall (7e) of the turntable base (7), and the boss portion (7d) A turntable upper plate (8) which is mounted on each upper surface of the rotary table (4) so as to cover the concave portion to form a closed hollow portion (9), and the closed hollow portion (9) has a passage ( 4a), a vacuum pump connected thereto, and a suction mechanism (10a, 22a, 23a) formed on the turntable upper plate (8) for sucking the record plate by negative pressure generated by the operation of the vacuum pump, The vacuum pump was operated to operate the adsorption mechanism and the hollow portion (9) was set to an extremely low pressure. A turntable characterized by the above is provided.

A fourth invention is a rotating shaft (4) having a passage (4a) formed therein.
And a boss portion (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted, and a concave portion that opens upward around the boss portion (7d) is formed. The turntable base (7), the outer wall (7e) of the recess of the turntable base (7) and the upper surfaces of the boss (7d) are abutted on the turntable base (7) to cover the recess and to form a closed hollow portion (9). Formed on the turntable upper plate (8), a vacuum pump connected to the closed hollow portion (9) through the passage (4a) of the rotary shaft (4), and the turntable upper plate (8) Adsorption mechanism (10a, 22a, 23a) for adsorbing a record board by negative pressure generated by the operation of the vacuum pump, a cabinet (2) for supporting the bottom surface of the turntable base (7) and the turntable (6). The air pressure supplied to the gap (25) between the turntable and the upper surface of the turntable And a levitation support mechanism for levitationally supporting 6 to actuate the suction mechanism by operating the vacuum pump and to make the hollow portion (9) extremely low in pressure. It is a thing.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a turntable device 1 to which a turntable according to the present invention is applied. A housing 3 is internally provided in a cabinet 2, and the housing 3 is fixed to an opening on the bottom surface of the cabinet 2 with a bolt 30. Case back 2a
The rotary shaft 4 is inserted into a shaft hole 3a formed in the center of the housing 3.

A plate member having a smooth upper surface, for example, a glass plate 5 is placed on the upper surface 2b of the cabinet 2, and an upper portion 3e of the housing 3 is fitted in a hole 5a formed at the center. The glass plate 5 is arranged concentrically with respect to the rotary shaft 4 and has a larger outer diameter than the turntable 6. Further, the upper surface 5b of the glass plate 5 is formed at a right angle to the axis of the rotary shaft 4 and has a high degree of parallelism with the bottom surface of the turntable 6. Further, the glass plate 5 and the housing 3 are in close contact with each other and are kept airtight.

A turntable 6 consisting of a turntable base 7 and two upper and lower parts of a turntable upper plate 8 is mounted on a glass plate 5 of the cabinet 2, and shaft holes 8a, 10b are bored at the center positions thereof. The rotary shaft 4 is fitted and fixed to the.

The turntable base 7 has an annular recess opening upward.
7a is formed, and an annular supporting rib 7b is concentrically formed with respect to the rotating shaft 4 from the bottom surface of the base 7 at a substantially central portion in the radial direction of the recess 7a. Of the hollow portion 7a, which is partitioned by the rib 7b, has several recesses 7c formed in the circumferential direction on the upper surface of the rib 7b, for example, three locations at every 120 ° center angle.
It connects the two outer chambers.

The upper end surfaces of the bearing portion 7d and the outer wall 7e of the turntable base portion 7 are provided with annular grooves 7g and 7h that are concentric with the shaft hole 7f. The O-rings for sealing are provided in these grooves 7g and 7h. 1
2 and 13 are fitted. The turntable upper board 8 is placed on the turntable base 7, and the bottom surface of the outer edge of the turntable base 8 is on the upper surface of the outer wall 7e via the O-ring 13, and the central portion is on the upper surface of the bearing portion 7d via the O-ring 12 and the middle. The parts are in contact with the upper surfaces of the ribs 7b, respectively. And, the recess 7a of the turntable base 7
A central portion 9 of the turntable 6 is formed by the turntable upper plate 8 and sealed by O-rings 12 and 13.

A circular concave portion 8b is formed on the central upper surface of the turntable upper plate 8.
Are formed so as to be concentric with the shaft hole 8a, and the disc member 10 is press-fitted into the recess 8b. On the bottom surface of the recess 8b, a radial passage 8c has one end opened to the shaft hole 8a and the other end having the recess 8b.
It is formed so as to be closed on the peripheral wall of 8b. A through hole 10a for communicating the closed end of the passage 8c to the outer periphery of the disc member 10
However, the turntable upper plate 8 is formed with through holes 8d that connect the passage 8c and the hollow portion 9, respectively.

An annular groove 8e is formed on the upper surface of the outer peripheral portion of the turntable upper plate 8 and an annular groove 1 is formed on the upper surface on the inner side of the through hole 10a in the peripheral portion of the disk member 10.
0c is formed in a concentric circle with the rotary shaft 4, and seal members 23, 22 formed of, for example, rubber members and having bendable lips 23a, 22a are mounted in the respective annular grooves 8e, 10c. ing.

The upper part of the rotary shaft 4 is fitted into the shaft holes 7f, 8a, 10b of the turntable base 7, the turntable upper plate 8 and the disk member 10, and the rotary shaft head 4e also serving as a center pin is screwed onto the upper end of the rotary shaft 4. By mounting the turntable base 4e, the turntable base 7 is mounted between the rotary shaft head 4e and the shaft retaining ring 4f that is mounted in the annular groove formed in the approximate center of the rotary shaft 4 and contacts the bottom of the turntable base 7. The turntable upper plate 8 and the disk member 10 are fastened and fixed, while the lower part of the rotary shaft 4 is rotatably fitted in the shaft hole 3a of the housing 3 and is fitted in an annular groove 4c provided on the peripheral surface of the lower end part. The fitted shaft retaining ring 14 is positioned in the axial direction to prevent upward deviation. A space 16 is defined between the lower end surface of the rotary shaft 4 and the bottom plate 15 fixed to the housing 3 and forming the bottom surface of the shaft hole 3a. When the turntable is operated, the shaft retaining ring 14 at the lower end of the rotary shaft 4 is prevented from coming into contact with any part of the surrounding housing 3.

A hole 4a is formed in the axis of the rotary shaft 4, one end of the hole 4a is opened to the lower end surface of the rotary shaft 4, and the other end is opened to the shaft hole 8a of the passage 8c of the turntable upper plate 8. An opening is formed in the bottom surface of the annular groove 4b formed on the peripheral surface at a position facing the end. Therefore, the hollow portion 9 of the turntable 6 has a hole 8d and a passage 8
c, the space 16 of the housing 3 through the annular groove 4b and the hole 4a
Is communicated to.

Further, one end of the housing 3 is a space portion of the housing 3.
16, a lateral hole 3b having the other end opened to the outer peripheral surface is formed,
The lateral hole 3b is formed by a joint 17 and a tube screwed into the hole 3b.
A vacuum pump (not shown) is connected via 18 for communication.

On the other hand, a circular concave portion 7i which is concentric with the rotary shaft 4 is formed on the bottom surface of the turntable base portion 7, and an annular space portion 19 is formed between the concave portion 7i and the housing 3 facing the concave portion 7i. . The housing 3 is provided with a vertical hole 3d whose upper end opens into the space 19 and a horizontal hole 3c communicating with the vertical hole 3d.
The lateral hole 3c is connected to a compressor (not shown) via a joint 20 and a tube 21 screwed into the hole 3c.

An O-ring 24 is fitted in an annular groove 4d formed at a predetermined position in the shaft hole 7f of the turntable base 7 of the rotary shaft 4, and a negative pressure system on a passage 8c side and a space portion 19 side, which will be described later. It shuts off the positive pressure system. Further, the shaft hole 3a of the housing 3
Also, grease is applied to the peripheral surface of the rotary shaft 4, and the shaft hole
A grease reservoir 3f is formed in an annular shape in the approximate center of 3a,
The grease reservoir 3f is filled with a grease 32 having a relatively high viscosity, and has a lubricating function for a fitting portion between the shaft hole 3a and the rotary shaft 4, a negative pressure system space portion 16 and a positive pressure system space portion 19. At the same time plays a sealing function between.

When the turntable device 1 is used in such a configuration, a record board (not shown) is placed on the turntable upper board 8 of the turntable 6. In this state,
The lips 22a and 23a of the seal members 22 and 23 contact the back surface of the record board, and a sealed space is formed between the record board and the upper surface of the turntable upper board 8.

Next, when the vacuum pump is operated, exhaust is performed, and the exhaust path, that is, the tube 18 to the lateral hole 3b of the housing 3,
Through the hole 4a of the rotary shaft 4, the outer peripheral annular groove 4b, the passage 8c of the turntable upper plate 8 and the small hole 10a of the disk member 10, the space defined by the record board and the suction seal members 22 and 23 is formed. The air is exhausted and decompressed, and the record board is adsorbed and fixed on the upper surface of the turntable upper board 8 to correct the warp.

On the other hand, the small holes 8d of the turntable 6 communicating with the above exhaust path are simultaneously exhausted, and the hollow portion 9 is depressurized, so that the upper surface of the turntable base 7 and the lower surface of the turntable upper plate 8 are O-rings. Completely adhered via 12 and 13,
The hollow portion 9 has an extremely low pressure close to a vacuum. As a result, the vibration generated by the rotation of a motor (not shown) and transmitted to the turntable base 7 via the cabinet 2 is difficult to propagate to the turntable upper plate 8 because the hollow portion 9 in a substantially vacuum state is interposed. In addition, since the turntable upper board 8 is mounted on the turntable base 7 with a small area, the reduction of the contact area between the turntable base 7 and the turntable upper board 8 reduces the transmission of vibrations. It is possible to prevent the vibration from being transmitted to the record board through the turntable 6 to a large extent.

Further, from a compressor (not shown), compressed air is supplied to the space portion 19 through the supply flow path, that is, the tube 21 and the holes 3c and 3d of the housing 3. At the start of supplying compressed air to the space 19, the bottom surface of the turntable base 7 is in contact with the smooth upper surface 5b of the glass plate 5, so that the flow path of the compressed air is closed. Space due to operation
The pressure of the compressed air in 19 gradually increases, and the turntable base 7, that is, the turntable 6 is pushed up and slightly floats from the upper surface 5b of the glass plate 5. As a result, a gap 25 is formed between the turntable base 7 and the upper surface 5b of the glass plate 5, and the compressed air flows out from the space 19 through the gap 25 toward the outside. The compressed air passing through the gap 25 evenly applies a constant pressure to the bottom surface of the turntable base 7 to levitate and support the turntable base 7 on the glass plate 5, thereby realizing stable rotation of the turntable.

In this embodiment, the structure in which the exhaust passage for depressurizing the hollow portion and the exhaust passage for adsorbing the record board are communicated and shared is described, but the present invention is not limited to this, and the turntable 6 adsorbs the record board. When the mechanism is not provided, as shown in FIG. 2, the bearing portion 7d of the turntable base portion 7 is provided with a lateral hole 7i for communicating the hollow groove 9 with the annular groove 4b in which the hole 4a of the rotary shaft 4 is opened. It's enough.

The glass plate 5 may be omitted if the upper surface of the cabinet is smooth, or a material having a surface roughness equal to or higher than that of the glass plate may be used instead of the glass plate. Absent.

As described above, according to the first aspect of the present invention, the rotary shaft having the passage bored therein, the boss portion centered on the vertical hole into which the rotary shaft is fitted, and the periphery of the boss portion. And a turntable base formed with a recess that opens upward in the recess, and is formed separately from the turntable base, and abuttingly mounted on the outer wall of the recess of the turntable base and each upper surface of the boss. And a vacuum pump connected to the closed hollow portion through the passage of the rotary shaft. The turntable upper plate is covered with a vacuum pump connected to the closed hollow portion through a passage of the rotary shaft. Since the turntable is designed to have a low pressure, the vibration propagating to the record board via the turntable can be extremely reduced.

That is, by making the hollow portion extremely low in pressure and reducing the air density in the hollow portion to a substantially vacuum level, it is possible to extremely reduce the vibration propagating to the record board via the turntable.

Moreover, since the turntable upper plate is formed separately from the turntable base and is mounted on the latter in abutment with a small area, the turntable upper plate acts synergistically with the structure that makes the hollow portion extremely low pressure. It is possible to further enhance the effect of reducing the transmission of vibration by reducing the contact area between the table base and the turntable upper board, that is, the substantial contact area between the turntable and the record board.

As a result, it is possible to prevent the vibration transmitted to the turntable base portion due to the rotation of the motor from being propagated to the record board to a considerable extent.

According to the second aspect of the invention, the rotary shaft (4) having the passage (4a) bored therein and the vertical hole (7f) into which the rotary shaft (4) is fitted are provided at the center. A turntable base (7) having a boss (7d) and a recess (7a) opening upward around the boss (7d); and a turntable base (7) formed separately from the turntable base (7). A turntable which is placed on the upper surface of the recess outer wall (7e) of the turntable base (7) and the upper surface of the boss (7d) so as to cover the recess (7a) to form a closed hollow portion (9). An upper plate (8), a vacuum pump connected to the closed hollow portion (9) through a passage (4a) of the rotating shaft (4), a bottom surface of the turntable base (7), and the turntable (8). The air pressure formed in the space (25) between the upper surface of the cabinet (2) for supporting 6) and the upper surface of the cabinet (2) causes Since the hollow table (6) is provided with a levitation support mechanism for levitationally supporting the table (6) and the hollow portion (9) is made to have an extremely low pressure by the operation of the vacuum pump, in addition to the effect of the first invention described above, The effect that the stable rotation of the table can be realized is obtained.

According to the third aspect of the invention, the rotary shaft (4) having the passage (4a) bored therein and the vertical hole (7f) into which the rotary shaft (4) is fitted are provided at the center. A turntable base (7) having a boss portion (7d) and a concave portion that opens upward around the boss portion (7d), and the turntable base portion (7)
Of the outer wall (7e) of the concave portion and the upper surface of the boss portion (7d), and a turntable upper plate (8) which is placed on the upper surfaces of the concave portion and covers the concave portion to form a closed hollow portion (9); (9)
A vacuum pump connected to the rotary shaft (4) through a passage (4a), and a suction mechanism formed on the turntable upper plate (8) to suck a record plate by negative pressure generated by the operation of the vacuum pump ( 10a, 22a, 23a), and the suction mechanism is operated by the operation of the vacuum pump, and the hollow portion (9) is made to have an extremely low pressure. Therefore, in addition to the effect of the first invention described above, The effect that the record board can be brought into close contact with the turntable top board to prevent its vibration and to correct the warp of the record board is obtained.

Further, according to the fourth aspect of the invention, the rotary shaft (4) having the passage (4a) bored therein and the vertical hole (7f) into which the rotary shaft (4) is fitted are opened at the center. A turntable base (7) having a boss portion (7d) and a concave portion that opens upward around the boss portion (7d), and the turntable base portion (7)
Of the outer wall (7e) of the concave portion and the upper surface of the boss portion (7d), and a turntable upper plate (8) which is placed on the upper surfaces of the concave portion and covers the concave portion to form a closed hollow portion (9); (9)
A vacuum pump connected to the rotary shaft (4) through a passage (4a), and a suction mechanism formed on the turntable upper plate (8) to suck a record plate by negative pressure generated by the operation of the vacuum pump ( 10a, 22a, 23a) and the turntable by the air pressure supplied to the space (25) between the bottom surface of the turntable base (7) and the upper surface of the cabinet (2) supporting the turntable (6). Since the suction mechanism is operated by the operation of the vacuum pump and the hollow portion (9) is set to an extremely low pressure, the levitation support mechanism for levitationally supporting 6 is provided. In addition to the effect, the effect that stable rotation of the turntable can be realized is obtained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a turntable device to which a turntable according to the present invention is applied, and FIG. 2 is a main part sectional view showing another embodiment of the present invention. 3 ... Housing, 4 ... Rotating shaft, 5 ... Glass plate, 6 ... Turntable, 7 ... Turntable base, 8 ... Turntable upper plate, 7i, 8d, 10a, through hole, 9 ... Hollow part, 12, 13, 24 ... O
Rings, 22, 23 ... Sealing members.

Claims (5)

(57) [Claims] 1. A rotary shaft (4) having a passage (4a) formed therein,
A boss portion (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted, and a recess (7a) opening upward are formed around the boss portion (7d). The turntable base portion (7) is formed separately from the turntable base portion (7), and contacts the upper surface of the recess outer wall (7e) and the boss portion (7d) of the turntable base portion (7). A turntable upper plate (8) which is mounted on and covers the concave portion (7a) to form a closed hollow portion (9), and a passage (4a) of the rotary shaft (4) in the closed hollow portion (9). And a vacuum pump connected via the vacuum pump, and the hollow table (9) is made to have an extremely low pressure by the operation of the vacuum pump. 2. A rotating shaft (4) having a passage (4a) formed therein,
A boss portion (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted, and a recess (7a) opening upward are formed around the boss portion (7d). The turntable base portion (7) is formed separately from the turntable base portion (7), and contacts the upper surface of the recess outer wall (7e) and the boss portion (7d) of the turntable base portion (7). A turntable upper plate (8) which is mounted on and covers the concave portion (7a) to form a closed hollow portion (9), and a passage (4a) of the rotary shaft (4) in the closed hollow portion (9). Pressure supplied to the vacuum pump connected through the space between the bottom surface of the turntable base (7) and the top surface of the cabinet (2) supporting the turntable (6). A levitation support mechanism for levitationally supporting the turntable (6) by means of By the operation of the pump, turntable, characterized in that the said hollow portion (9) to the pole to the low pressure. 3. A rotating shaft (4) having a passage (4a) formed therein,
A turntable having a boss portion (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted and a concave portion opening upward around the boss portion (7d). The base (7) and the outer wall (7) of the recess of the turntable base (7)
e) and a turntable upper plate (8) which is placed in contact with each upper surface of the boss portion (7d) and covers the recess to form a closed hollow portion (9), and the closed hollow portion (9). A vacuum pump connected through the passage (4a) of the rotating shaft (4),
An adsorption mechanism (10a, 22a, 23a) formed on the turntable upper plate (8) for adsorbing a record disc by a negative pressure generated by the operation of the vacuum pump, and the adsorption mechanism is operated by the operation of the vacuum pump. Together with the hollow part (9)
A turntable characterized by making the pressure extremely low. 4. A hollow portion (9) of the turntable (6).
The suction mechanism and the suction mechanism are connected to a vacuum pump through a common passage (4a, 8c).
The listed turntable. 5. A rotary shaft (4) having a passage (4a) formed therein,
A turntable having a boss portion (7d) centered on a vertical hole (7f) into which the rotary shaft (4) is fitted and a concave portion opening upward around the boss portion (7d). The base (7) and the outer wall (7) of the recess of the turntable base (7)
e) and a turntable upper plate (8) which is placed in contact with each upper surface of the boss portion (7d) and covers the recess to form a closed hollow portion (9), and the closed hollow portion (9). A vacuum pump connected through the passage (4a) of the rotating shaft (4),
Adsorption mechanisms (10a, 22a, 23a) formed on the turntable upper board (8) for adsorbing the record board by negative pressure generated by operation of the vacuum pump, a bottom surface of the turntable base (7) and the turntable (7). 6) a levitation support mechanism for levitationally supporting the turntable 6 by the air pressure supplied to the gap (25) between the cabinet (2) supporting the turntable 6 and the adsorption mechanism by the operation of the vacuum pump. A turntable, characterized in that the hollow part (9) is operated and brought to an extremely low pressure.