JPS6032251B2 - Video tape recorder cylinder device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylinder device that is used in a video tape recorder and is mounted with a magnetic head and is directly driven.

There is an apparatus in which the cylinder for the magnetic head of a video tape recorder is directly driven by a prior art flat plate electric motor.

This flat plate electric motor is roughly constructed as follows.
An annular permanent magnet is fixed to a rotor disc fixed to a rotating shaft, and a plurality of drive coils are fixed to a stator yoke formed from a disc part and a cylindrical part, and this drive coil is connected to the above permanent magnet with an air gap. The rotor discs are opposed to each other in all directions on the axis, and a large number of teeth are provided on the outer circumference of the rotor disk.

A detection element is attached to the stator yoke side, which faces the toothed portion across an air gap in the ball direction. This detection element uses a magnetically sensitive element (for example, a Hall element), and detects the position and speed of the rotor by changes in magnetic flux, and uses this signal to control the supply voltage and current and apply them to each drive coil. is rotated in a predetermined direction and speed. The flat plate electric motor configured in this manner is housed in a fixed cylinder, and the upper cylinder above the fixed cylinder is fixed to the upper end side of the rotating shaft and is driven to rotate.

A magnetic head for recording and reproducing magnetic tape is attached to the upper cylinder. However, a compact cylinder device with a built-in flat-plate electric motor must be equipped with a rotating transformer that sends and receives signals from the magnetic head of the rotating upper cylinder to the stationary cylinder, and a connecting wire that leads to the outside. . In addition, there are many connection wires for multiple detection elements and wiring for connecting multiple drive coils and pulling them out to the outside, but it is difficult to wire and pull out a large number of connection wires in a narrow cylinder device, making it difficult to work. It was bad and the external shape was large. This invention provides connection wires for extracting signals from the magnetic head of the upper cylinder and leading them to the outside from the fixed cylinder, connection wires for connecting the detection element and leading them to the outside, and connection wires for connecting the drive coil and leading them to the outside. To provide a cylinder device in which wiring terminal parts of each printed wiring board are brought out from a notch provided in a cylindrical part of a fixed cylinder, the cylinder is made compact, and the workability of wiring connection is improved. The purpose is to

FIG. 1 is a vertical cross-sectional view of a main part of a shilling device incorporating a flat plate type electric motor, showing an embodiment of the present invention.

Reference numeral 1 denotes a thin flat plate electric motor, which is constructed as follows.

Reference numeral 2 denotes a rotating shaft, which is rotatably supported by a fixed cylinder 4 via a bearing 3.

This fixed cylinder has a cylindrical portion 4a and is made of a non-magnetic material. Reference numeral 5 denotes a rotor disk made of magnetic material, which is attached to a boss 6 fixed to the rotating shaft 2. A large number of teeth 5a are provided on the outer circumference, and the position of the rotor can be adjusted by changes in magnetic flux. The speed is being detected.

Reference numeral 7 denotes an annular permanent magnet fixed on the rotor disk 5, which is magnetized alternately into N and S poles in the circumferential direction.

A stator yoke 8 is made of a magnetic material, and is composed of a disk portion 8a and a cylindrical portion 8b extending downward from the outer circumferential side of the disk portion 8a.

9 is a plurality of drive coils fixed in the disk portion 8a; 1;
Reference numeral 0 denotes detection elements arranged at multiple locations on the toothed portion 5a of the rotor disk 5 with small air gaps in the mari direction, and each consisting of a magnetically sensitive element, such as a Hall element, detects changes in the magnetic flux of the toothed portion 5a. The position and speed of the rotor are detected, and the voltage and current supplied to each drive coil 9 are controlled by this signal to give a predetermined rotation to the rotor disk 5.

Next, reference numeral 11 denotes an annular holding section, which is made of a synthetic resin material having ballistic properties, is fixed to the disk section 8a of the stator yoke 8, and is arranged at multiple locations in the circumferential direction. It supports the detection element 10.

12 is a second printed wiring board for the detection element, which has an annular shape and is fixed to the holding member 11 on the inner circumferential side of the stator yoke 8;
Printed wiring is provided as a connection line drawn out from each detection element 10 to the outside, and the wiring terminal portion 12a is connected to the notch 8c of the cylindrical portion 8b of the stator yoke and the cylindrical portion 4a of the fixed cylinder 4.
It passes through the notch 4c and is exposed to the outside.

Reference numeral 16 denotes a first printed wiring board for the drive coil, which has an annular shape and is fixed between the disk portion 8a of the stator yoke 8 and the drive coil 9, and connects and wires these drive coils to the outside. Printed wiring is provided as the connecting wiring to be drawn out, and the wiring terminal portion 16a passes through the cutout portions 8c and 4c and is exposed to the outside.

The first and second printed wiring boards 16 and 12 and 12
is shown in a bottom view in FIG. A plurality of printed wirings 13 are provided on both sides of the second printed wiring board 12, and each detection element 10
A plurality of wiring terminals 14 are formed in the wiring terminal portion 12a, and external connection wires (not shown) are connected by soldering to the wiring terminal portion 12a. The first printed wiring board 16 includes a plurality of printed wirings 17.
is applied to one side, a wiring terminal 18 is formed on the wiring terminal portion 16a, and an external connection wire (not shown) is connected by soldering. Each drive coil 9 has a lead wire 19 printed on the wiring 17.
Wire connections are made by soldering connections. 1st
Returning to the figure, reference numeral 19 denotes a magnetic shield inserted inside the cylindrical part and bottom of the fixed cylinder 4, which is made of a thin magnetic material and surrounds the outer circumference and lower part of the flat motor 1. Ori,
A notch is provided in a part of the cylindrical part, and the wiring terminal parts 12a and 16a are suitable for this.

An upper cylinder 20 is disposed with a slight clearance from the fixed cylinder 4, is made of a non-magnetic material, and is connected to the rotating shaft 2.
It is attached to a boss 21 fixed to the upper end of the holder and rotated.

This upper cylinder 201 has a pair of magnetic heads (not shown) attached at symmetrical positions at the bottom for recording and reproducing a magnetic tape (not shown) running around the outer circumference of the cylindrical part. . Reference numeral 22 denotes a rotating transformer, which consists of a rotating coil 23 fixed to the upper cylinder 20 side, and a fixed coil 24 fixed to the stator yoke 6 with an air gap in the direction of the coil, and a coil 24 fixed to the stator yoke 6. Sends and receives magnetic head signals.

A third printed wiring board 25 is fixed onto the disk portion 8a of the stator yoke 8 and connects the stationary coil, as shown in a plan view in FIG.

Printed wiring 26 is provided as a connection line drawn out from the fixed side coil 24 to the outside, and a lead wire 28 of the fixed side coil is connected by soldering. The wiring terminal portion 25a of the printed wiring board 25 passes through the cutout portion 4c of the fixed cylinder 4 and is brought out to the outside to form a wiring terminal 27. thus,
Each electric element within the cylinder portion is connected by each printed wiring board, and wiring terminals are brought out to the outside, so that external connection wires can be easily connected.

As described above, according to the present invention, the first printed wiring board is annular and has printed wiring for connecting each drive coil.
A second printed wiring board is fixed between the stator yoke and the drive coil, and has printed wiring for connecting the detection element, and is disposed on the inner circumferential side of the stator yoke. A third printed wiring board with printed wiring for connecting the stationary side coil is fixed onto the disc part of the stator yoke, and the wiring terminal part of each printed wiring board is connected to the cutout of the disc part of the stationary cylinder. Since each electric element is exposed to the outside through the notch, a small space is required for connecting each electric element, the cylinder part can be made compact, and wiring workability is improved.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing the main parts of a cylinder device of a video tape recorder according to an embodiment of the present invention, and FIG.
FIG. 3 is a bottom view of the first and second printed wiring board sections in the figure, and FIG. 3 is a plan view of the third printed wiring board section in FIG. 1. 1...Flat type electric motor, 2...Rotating shaft,
4... Fixed cylinder, 4a... Cylindrical part, 4c...
...Notch, 5...Rotor disk, 7...
・Permanent magnet, 8...Stator iron, 8a...
Disk portion, 9... Drive coil, 10... Detection element, 12... Second printed wiring board, 12a...
...Wiring terminal section, 13...Printed wiring, 1
6...First printed wiring board, 16a...
・Wiring terminal section, 17...Printed wiring, 20...
...upper shilling, 22...rotating transformer, 2
3... Rotating side coil, 24... Fixed side coil, 25... Third printed wiring board, 25a
...Wiring terminal section, 26...Printed wiring. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1 A permanent magnet is fixed to the rotor disk attached to the rotating shaft,
A plurality of drive coils facing this permanent magnet in the axial direction with an air gap in between are fixed to the stator yoke side, the movement of the rotor disk is detected by a detection element, and the signal from this detection element is used to detect the supply power. a flat plate electric motor configured to control and apply a voltage to the drive coil to rotate the rotor disk;
It consists of a fixed cylinder that houses this flat plate electric motor, and a magnetic head that is placed on top of this fixed cylinder.
In a device comprising an upper cylinder fixed to the upper end of the rotating shaft and rotated, the upper cylinder has a thin annular shape and is fixed between the disk part of the stator yoke and the drive coil,
a first printed wiring board, which is provided with printed wiring for connecting these drive coils, and has a wiring terminal portion exposed outside through a notch provided in the cylindrical portion of the fixed cylinder; It is arranged on the inner circumferential side of the stator yoke, and is provided with printed wiring for connecting the detection element, and the wiring terminal section extends outside through the notch of the fixed cylinder. a second printed wiring board, which comprises a rotating side coil fixed in the upper cylinder and a fixed side coil facing the coil with an air gap in the axial direction and fixed on the stator yoke; A rotary transformer for sending and receiving signals from the magnetic head to the fixed part, and a wiring terminal fixed to the disc part of the stator yoke and printed wiring for connecting the fixed side coil. 1. A cylinder device for a video tape recorder, comprising: a third printed wiring board whose portion is exposed to the outside through a cutout portion of the fixed cylinder.