JPS61142566A - Record player - Google Patents

Abstract

PURPOSE:To transmit the rotation of a magnet smoothly to the periphery of a turn table by rotating the rotary shaft of the turn table between the 1st and 2nd receiving rollers and pressing rollers without vibration. CONSTITUTION:When a motor 40 is driven and the rotary shaft 41 is rotated, the magnet 47 is rotated through a magnet holding shaft 43 and the turn table 20 is rotated by the friction between a rubber layer 48 and the outer periphery of the turn table 20. In this case, the magnet 47 is attracted to a magnetic substance 35 on the outer periphery of the turn table 20 through the rubber layer 48 by the attracting force and is not attracted to the magnetic substance 35 through the rubber layer 48 by a specific pressing force. Consequently, the rotation of the magnet 47 can be transmitted to the magnetic substance 35 extremely smoothly and the turning force of the rotary shaft 41 is sufficiently transmitted to the turn table 20 by the attracting force of the magnet 47.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention can save the rotational driving force and downsize the rotational driving source, reliably prevent the vibration of the rotating shaft of the turntable, and increase the This invention relates to a record player that can provide good sound quality.

"Prior Art" Generally, in a record player that rotates a turntable using a motor and extracts an electrical signal from a record placed on the turntable via a pickup, a driving device installed on the rotating shaft of the motor is used. Belt drive system in which a belt is wound around the roller and the outer circumference of the turntable: An idler is rotatably provided between the driving roller provided on the rotating shaft of the motor and the inner surface of the outer peripheral wall of the turntable. In these record players, as shown in Fig. 4, the rotation shaft 2 of the turntable l is rotated in order to reduce rotational friction and receive thrust loads. Center of the lower end surface of shaft 2 and bearing 3
The bearing 3 is rotatably fitted into the guide hole 4 of the bearing 3 while being supported by a ball 5 provided between the bottom surface of the guide hole 4 and the bottom surface of the guide hole 4 .

``Problems to be Solved by the Invention'' In the above-mentioned belt drive, rim drive, etc. turntable rotation drive means, the driving roller and turntable are subject to side pressure due to the tension force of the belt and pressure force from the idler, respectively. Since side pressure and the like are applied, friction loss occurs, which requires extra rotational driving force from the motor, resulting in a large motor, which poses the problem of increased vibration of the turntable and record.

In addition, in the belt drive and rim drive,
There was also the drawback that the belt and idler deteriorated over time, which became a hindrance.

In addition, in the mll shaft bearing 3, the guide hole 4 and the rotating shaft 2
Since it is necessary to provide lubricating oil between the guide hole 4 and the rotating shaft 2, a very small gap is formed between the guide hole 4 and the rotating shaft 2. For this reason, when the rotary shaft 2 rotates, the rotary shaft 2 performs a grinding motion using its lower end surface as a fulcrum, causing vibration, which adversely affects the playback quality when playing records, the durability of records and cartridges, etc. There was a drawback that these functions could not be fully demonstrated.

In addition to the above, there is also a direct drive type record player in which a low-speed motor is directly connected to the shaft of the turntable, but although there is no intervention to transmit rotation, this type controls the rotation by applying a servo to the motor. Therefore, the quality of the sound played by this record player cannot necessarily be said to be good.

"Means for Solving the Problems" In order to solve the above problems, the present invention has the following configuration. That is, in a record player that rotates a turntable by a motor and extracts an electrical signal from a record on the turntable via a pickup, there is a rotary shaft that rotates with the center of the lower end supported by the base, and an outer circumference of the rotary shaft. Eleventh and second receiving rollers are arranged on one side, are spaced apart from each other, circumscribe the outer periphery of the rotating shaft, and are rotatably provided with a fixed position on the base; The rotary shaft is located on the opposite side of the first and second receiving rollers, is eccentrically rotatably and fixably provided on the base, and circumscribes the outer periphery of the rotating shaft to support the rotating shaft in the first and second receiving rollers. A push roller that presses against the roller, a magnetic material provided all around the circumferential wall of the turntable, and a magnetic material provided coaxially with the rotating shaft of the motor movably held at the base via a holding member, and having a cross section. and a magnet for transmitting the rotation of the rotating shaft of the motor to the turntable by adhering the outer circumferential surface of the magnet, which is formed in a circular shape, to the magnetic body by its own attractive force, and the first and second receivers The rotary shaft of the turntable can be rotated between the roller and the push roller without wobbling.

"Embodiment" Hereinafter, an embodiment of the present invention will be described based on FIGS. 1 to 3. In the figure, reference numeral 11 denotes a substrate (base) provided in the record player cabinet, and a through hole 12 is formed in a predetermined location of this base 11. In addition, the board 1
1, the support plate (base) 13 is attached to the bolt (by 4 the substrate 11
It is provided parallel to and spaced apart from the substrate 11. A shaft support (center bolt) 15 is screwed into the center of the support plate I3 so as to be movable forward and backward relative to the base plate 11, and a head 16 of the shaft support 15 has a center bolt 15 on the side of the base plate, which is perpendicular to the base plate 11. The rotating shaft 17 is also brought into contact. The rotating shaft 17 is inserted through the substrate 11 so as not to touch the inner peripheral surface of the through hole 12 . A ball portion 18 is formed at one end of the rotating shaft 17, and this ball portion 18 is brought into contact with the head 16. Also, the rotating axis! A flange 19 is provided at the other end of 7, and a turntable 20 is attached to this flange 19 in parallel with the substrate 11. . Also, the substrate I
As shown in FIG. 2, first receiving rollers I are arranged on one side of the outer circumferential surface of the body 21 of the rotating shaft 17, and are in circumscribed contact with the outer circumferential surface of the body 21 at a distance from each other. 22
and a second receiving roller 23 are rotatably provided with their respective positions fixed. That is, the first receiving roller 22 and the second receiving roller 23 are rotated by fixed shafts 24 and 25 screwed and fixed to the substrate 11 while being in circumscribed contact with the outer peripheral surface of the body portion 21 of the rotating shaft 17, respectively. They are fitted freely. Further, a push roller 26 is disposed on the other side of the outer periphery of the body portion 21 of the rotating shaft 17 . The push roller 26 is rotatably fitted onto an eccentric shaft 27 screwed onto the substrate 11. The eccentric shaft 27 consists of a screw shaft 29 integrally provided on one side of the connecting plate 28, and a shaft portion 30 integrally provided eccentrically with respect to the screw shaft 29 on the other side of the connecting plate 28, The screw shaft 29 is rotatable on the board II and is flat)
31, and are fixedly screwed together. A rotating rod 32 is provided at one end of the screw shaft 29, and a nut 31
By loosening and operating the rotation rod 32 to turn the screw shaft 29, the body 2 of the rotation shaft 17! The outer circumferential surface of the push roller 26 moves forward and backward relative to the outer circumferential surface of the first receiving roller 22.
, the body 2 of the rotating shaft 17 is attached to the outer peripheral surface of the second receiving roller 23.
The outer peripheral surface of 1 can be pressed against it. Note that a in FIG. 2 indicates the amount of eccentricity between the screw shaft 29 and the shaft portion 30. The upper surface of the turntable 20 has a concave conical surface 3.
3 is formed. Further, a magnetic material (mild steel for electromagnetic use) 35 is provided on the outer peripheral wall 34 of the turntable 20 over the entire circumference. On the other hand, the turntable 2 is mounted on the board 11.
0, and a lever 38 is provided so as to be horizontally rotatable via a bearing 36 and a shaft 37. A holding member 39 is fixedly provided at the tip of the lever 38 in a hanging manner.

A motor 40 is attached to its rotating shaft 4 at the lower end of this holding member 39.
1 is attached vertically upward. A magnet holding shaft 43 is coaxially connected to the rotating shaft 4I by a coupling 42. This magnet holding shaft 43 is rotatably held by the holding member 39 via bearings 44 and 45. A recess 46 is formed at the upper end of the magnet holding shaft 43, and a magnet 47 is fitted into the recess 46. The magnet 47 is fixed to the magnet holding shaft 43 at the portion where it fits into the recess 46 and is provided coaxially with the rotating shaft 41 and at approximately the same height as the outer periphery of the turntable 20 . The magnet 47 is made of, for example, samarium cobalt, is magnetized in the axial direction, and has an N pole and an S pole at both ends. Also, magnet 4
7 is provided with a rubber layer (rubber cap) 48.

Next, the operation of the record player configured as described above will be explained.

First, with the nut 31 loosened, the rotating rod 32
The eccentric shaft 27 is rotated by the first receiving roller 22. Second
Press the outer circumferential surface of the body portion 2I of the rotary shaft 17 against the outer circumferential surface of the receiving roller 23 using a push roller 26 with an appropriate pressing force.
Tightening the nut 31 fixes the eccentric shaft 27 to the base plate 11. As a result, the position of the rotating shaft 17 is determined so that the rotating shaft 17 is orthogonal to the substrate 11, and the rotating shaft 17 can rotate without wobbling.

On the other hand, the magnet 47 is held by the lever 38, the holding member 39, etc., and is attracted to the outer periphery of the turntable 20 via the rubber layer 48 by its own attractive force. When the motor 40 is operated to rotate the rotating shaft 41, the magnet 47 rotates via the magnet holding shaft 43, and the rubber layer 48 and turntable 20 are rotated.
The turntable 20 is rotated by friction with the magnetic body 35 on the outer periphery of the turntable 20. At this time, the magnet 47 is attracted to the magnetic body 35 on the outer periphery of the turntable 20 via the rubber layer 48 due to its attraction force, and the rubber layer 48 is attached to the magnetic body 35 by a special pressing force. Since the magnet 47 is not attracted to the turntable 20 through the magnetic body 35, the rotation of the magnet 47 to the magnetic body 35 on the outer periphery of the turntable 20 is extremely smooth. 20. Therefore, compared to conventional belt drives and rim drives, less rotational driving force is required, the motor 40 can be made smaller, the amount of vibration generated is reduced, and it is possible to use high-speed rotation motors. Being able to use a rotating motor means that it is possible to obtain high-fidelity reproduction sound quality.

Moreover, when the motor 40 is operated, the turntable 20
rotates, but at this time, since the rotating shaft 17 rotates without wobbling, the turntable 20 also rotates smoothly without wobbling. Therefore, the shake of the record caused by the shake of the rotary shaft in the past is prevented, and the playback sound quality when playing the record is greatly improved.
The durability of cartridges, etc. will not be compromised.
These functions can be fully demonstrated. In addition,
The outer peripheries of the first receiving roller 22, second receiving roller 23, and push roller 26 may be coated with rubber to further prevent vibration.

Further, in the above embodiment, the magnet 47 was attracted to the magnetic body 35 on the outer periphery of the turntable 20 via the rubber layer 48, but the present invention is not limited to this.
A magnetic material is provided on the inner surface of the outer peripheral wall of the magnetic material, and a magnet 47 is attached to this magnetic material.
It is also possible to make it so that it is adsorbed.

"Effects of the Invention" The rotation of the magnet is smoothly transmitted to the circumferential surface of the turntable, and the rotational driving force is reduced accordingly.Therefore, the rotational driving force of the motor can be reduced, and the motor can be made smaller. As a result, the amount of vibration generated can be significantly reduced, and a high-speed rotating motor can be used.

In addition, since the rotating shaft can be appropriately pressed against the 11th and 2nd receiving roller by the push roller, the position of the rotating shaft of the turntable is determined, and therefore, the wobbling of this rotating shaft can be reliably prevented. As a result, high-fidelity reproduction sound quality can be obtained when playing a record, and these functions can be fully demonstrated without impairing the durability of the record, cartridge, etc.

[Brief explanation of drawings]

FIG. 1 is a partially omitted sectional view showing one embodiment of the present invention, and FIG.
The figure is a cross-sectional view taken along the line ■-■ in Figure 1, Figure 3 is a cross-sectional view taken along the line ■-■ in Figure 1, and Figure 4 is a vertical cross-sectional view showing the bearing unit part of a conventional record player. be. 11... Board (base), 17... Rotating shaft, 20... Turntable, 22...
・First receiving roller, 23... Second receiving roller, 26... Push roller, 35... Magnetic material (mild steel for electromagnetic use), 39...・・Holding member, 40
...Motor, 41...Rotating shaft, 47.
·····magnet.

Claims (1)

[Claims] In a record player that rotates a turntable by a motor and extracts electrical signals from records on the turntable via a pickup, there is a rotary shaft that is supported by a base and rotates at the center of the lower end, and one side of the outer periphery of the rotary shaft. first and second receiving rollers, which are arranged at a distance from each other, circumscribe the outer periphery of the rotating shaft, and are rotatably provided with a fixed position on the base; 1. Located on the opposite side of the second receiving roller, is eccentrically rotatably and fixably provided on the base, and is circumscribed around the outer periphery of the rotating shaft to connect the rotating shaft to the first and second receiving rollers. a push roller that presses against the turntable, a magnetic material provided all around the peripheral wall of the turntable, and a magnetic material provided coaxially with the rotating shaft of the motor movably held at the base via a holding member, and a magnet that transmits the rotation of the rotating shaft of the motor to the turntable by adhering its outer circumferential surface, which has a circular cross section, to the magnetic body by its own attractive force, and transmits the rotation of the rotating shaft of the motor to the turntable. A record player characterized in that the rotating shaft of the turntable can be rotated between a receiving roller and a pushing roller without wobbling.