JP2600847Y2 - Rotary transformer for magnetic recording / reproducing device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus such as a VTR and a rotary transformer incorporated in a head drum apparatus for extracting a detection signal of a rotary head such as a video head outside the head drum apparatus. It is.

[0002]

2. Description of the Related Art FIG. 1 shows an example of a head drum device.
A rotating shaft 6 is supported on the fixed drum 2 via a ball bearing 4, and a rotating drum 8 is fixed to the rotating shaft 6. A video head 10 is mounted on the rotating drum 8, and in order to extract a detection signal of the video head 10,
A rotary transformer including a rotor 12 and a stator 14 is provided. The rotor 12 is fixed to the rotating drum 8, is connected to the video head 10, and rotates with the video head 10. The stator 14 is fixed to the fixed drum 2. In order to extract a signal from the stator 14 to the outside, a printed wiring board 16 is attached to the stator 14, and the stator 14 and the wiring of the printed wiring board 16 are connected.

[0003] A motor is provided on the rotating shaft 6 to rotate the rotating drum 8 via the rotating shaft 6. In this example, the motor is mounted on the lower end side of the rotating shaft 6, and the motor includes a rotor cover 17 fixed to the rotating shaft 6, a rotor magnet 18 provided on the rotor cover 17 , and a stator coil 20 fixed to the fixed drum 2. It is composed of Reference numeral 22 denotes a motor printed wiring board that supplies a motor driving current to the stator coil 20.

A conventional example of a stator 14 of a rotary transformer will be described with reference to FIGS. The core 24 of the stator 14 is formed with grooves 26 in which coil windings 28 are formed concentrically. The coil windings 28 are wound around the grooves 26.
In this example, four grooves 26 are formed concentrically and a coil winding 28 of four channels is wound. In order to guide the lead wire of the coil winding 28 wound in the groove 26 to the printed wiring board 16, two lead wire lead-out grooves 30 crossing the groove 26 are provided.
Individually formed. The printed wiring board 16 is attached to the back surface of the core 24 (the side where the groove 26 is formed is referred to as the front surface side), and the back surface of the printed wiring board 16 (the core 24 is attached to the printed wiring board 16). Side is defined as a front side), a lead wire connection portion 32 is provided, and the coil winding 2 wound around the core groove 26 via the lead wire drawing groove 30 is provided.
Eight lead wires 34 are drawn out to the lead wire connection portions 32 on the rear surface side, and are connected to predetermined terminals of the printed wiring board 16 by soldering at the lead wire connection portions 32.

[0005]

In the case of the conventional stator structure as shown in FIGS. 2 and 3, the lead wire 34 of the coil winding wound in the groove of the core is connected to the printed wiring board 16.
In order to connect the lead wire 34 to the printed wiring board 16 with the surface of the lead wire connection portion 32 shown in FIG. 2B facing upward, the distributed lead wire 34 is the lead wire of any channel. It is necessary to know for sure. If the lead wire 34 is not identified, an incorrect connection will occur.

Further, as shown in FIG. 2, since the lead wire connection portion 32 faces the fixed drum 2, the lead wire connection portion 32 has high accuracy so as not to contact the fixed drum 2 and leak. Wiring means is required. As a result, there is a disadvantage that the number of assembly steps of the rotary transformer increases.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotary transformer having a structure capable of facilitating an assembling operation and reducing the possibility of erroneous connection.

[0007]

In the rotary transformer of the present invention, the stator has a flexible printed wiring board attached to the back surface of the core, and a lead wire connected to the core-side surface of the printed wiring board. has a section, leads coming out of the coil winding of the core of the stator in the lead wire connection section is connected to the printed circuit board, the printed
Adhesive area to the core on the surface of the wiring board opposite to the core
High rigidity reinforcement in the area from to the lead wire connection
The board is stuck.

In a preferred embodiment, the adhesive application area where the printed wiring board is attached to the stator side core is formed so as to protrude from the area where the printed wiring board is bonded to the core to the vicinity of the lead wire connection portion. This protruding adhesive application area is used to temporarily fix the lead wire when connecting the lead wire protruding from the coil winding to the lead wire connection part of the printed wiring board to facilitate the connection work. You.

In another preferred embodiment, a plurality of lead wire leading grooves for leading a lead wire from a winding are formed on the surface side of the stator side core, and the lead wire leading grooves are provided for each channel of the coil winding. Are provided independently for each connection direction. The length of each lead wire extending from the coil winding of each channel wound on the stator core through each lead wire drawing groove is different at the beginning and end of winding.

[0010]

An embodiment will be described with reference to FIGS. The stator-side core 40 is formed with four concentric four-channel grooves 42 as in FIG. As shown in FIG. 5A, in order to lead the lead wire of the coil 44 wound around each groove 42 toward the printed wiring board 48, lead wire leading grooves 46-1 to 46-4 are provided for each channel. Is formed.

A printed wiring board 48 for taking out a signal to the outside is adhered to the back side of the core 40 (the side on which the groove 42 is provided is referred to as the front side) by an adhesive 50. Front side of printed wiring board 48 (side with core 40)
Is provided with a lead wire connecting portion 52, and the lead wire 54 of the coil winding 44 of each channel is taken out on the printed wiring board 48 through the respective lead wire taking out grooves 46-1 to 46-4. The printed wiring board 4 at the connection portion 52
8 are connected by soldering. The positions of the terminals at the lead connection portion 52 are such that the lead wires 54 taken out from the respective lead wire taking-out grooves on the printed wiring board 48 for each channel have different lengths at the beginning and end of winding. Are arranged differently.

The adhesive layer 50 is applied not only to the bonding area between the core 40 and the printed wiring board 48 but also to the vicinity of the lead wire connection part 52, and the lead wire 54 is connected to the terminal of the lead wire connection part 52. At the time of soldering connection, by temporarily fixing the lead wire 54 to the protruding adhesive area 50, the work of connecting the tip of the lead wire and the terminal of the printed wiring board can be facilitated.

[0013] Examples of the printed wiring board 48 to use the full lexical Bull printed wiring board. At that time, the printed wiring board 4
In order to reinforce the strength of the printed wiring board 8 and to prevent the lead wires 54 connected to the printed wiring board 48 from breaking, a rigid reinforcing plate 56 is attached to the back surface of the printed wiring board 48. The reinforcing plate 56 is attached to at least a region from the back surface side of the core 40 to the lead wire connection portion 52.
As the reinforcing plate 56, a hard plastic sheet is used, and for example, a PET (polyethylene terephthalate) sheet or the like can be used.

Although the embodiment is described as an example in which the present invention is applied to the head drum device shown in FIG. 1, the head drum device to which the rotary transformer of the present invention is applied is limited to the one shown in FIG. However, the present invention can be applied to head drum devices of various magnetic recording / reproducing devices, such as a stationary VTR, a DAT (Digital Audio Tape Recorder) and a camera-integrated VTR.

[0015]

According to the rotary transformer of the present invention, a flexible printed wiring board is attached to the back surface of the stator core, and the printed wiring board has a lead wire connecting portion on the core side surface, and the lead wire connection is provided. Since the lead wire coming out of the coil winding of the stator core is connected in the section, the work of connecting the lead wire of the coil winding of the core to the printed wiring board can be done on the same surface, as in the past. Therefore, it is not necessary to route the lead wire to the back surface of the printed wiring board, and the connection is not mistaken. In addition, since the lead wire connection portion is on the core side of the printed wiring board, there is no defect in contact with other portions, and high-precision connection means is not required, and the number of assembling steps can be reduced accordingly.

If the printed wiring board is bonded to the stator side core and the adhesive application area is formed so as to protrude from the bonding area with the core to the vicinity of the lead wire connection portion, the lead wire can be temporarily fixed. Connection work becomes easy. A lead wire drawing groove for drawing the lead wire from the coil winding on the surface side of the stator side core is provided for each channel of the coil winding, and if it is oriented in the respective connection direction, the drawn lead wire can be connected without erroneous connection Can be connected.

Each lead wire extending from the coil winding of each channel wound on the stator side core through each lead wire lead-out groove is made different in length at the beginning and end of winding, so that the winding starts. And the end of the winding can be easily identified, and erroneous connection is eliminated. Flexible printed circuit boards
Because it is, out of the opposite surface to the core side, by bonding One takes a large reinforcing plate rigidity in the area over the lead wire connecting portion from the adhesive area to at least the core, it is possible to have a rigidity to that portion, No break in the connected lead wires.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing an example of a head drum device.

FIG. 2 is a partial sectional view showing a stator of a conventional rotary transformer together with a fixed drum.

3A and 3B are diagrams showing a stator of a conventional rotary transformer, wherein FIG. 3A is a plan view of a coil winding side, and FIG.

FIG. 4 is a partial cross-sectional view showing a stator of a rotary transformer according to one embodiment together with a fixed drum.

5A and 5B are diagrams showing a stator of the rotary transformer according to the embodiment, wherein FIG. 5A is a plan view of a coil winding side, and FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 2 fixed drum 8 rotating drum 40 stator core 42 coil winding groove 44 coil 46-1 to 46-4 lead wire extracting groove 48 printed wiring board 50 adhesive 52 lead wire connection part 54 lead wire 56 reinforcing plate

Continued on the front page (56) References JP-A-62-12110 (JP, A) JP-A-58-195418 (JP, U) JP-A-61-111116 (JP, U) (58) Fields investigated (Int) .Cl. ⁶ , DB name) H01F 38/14

Claims (4)

(57) [Scope of request for utility model registration] 1. A head drum device of a magnetic recording / reproducing device, comprising: a stator mounted on a fixed drum; and a rotor mounted on a rotating drum, connected to a rotating head and arranged opposite to the stator, The stator and the rotor each have a core facing each other on the surface side, have concentric grooves on their opposing surfaces, and have a coil winding in the grooves. A flexible printed wiring board is adhered to the back surface of the printed wiring board, and the printed wiring board has a lead wire connecting portion on the core side surface, and the lead wire coming out of the coil winding of the stator core at the lead wire connecting portion. A wire is connected to the printed wiring board, and the printed wiring board is
Of the surface opposite to the core side of the
A rigid plate with high rigidity is attached to the area over the wire connection.
A rotary transformer characterized by being mounted . 2. The method according to claim 1, wherein the adhesive application area for attaching the printed wiring board to the stator-side core is formed so as to protrude from the area where the printed wiring board is bonded to the core to the vicinity of the lead wire connection part. Rotary transformer. 3. A plurality of lead wire leading grooves for leading a lead wire from a winding are formed on the surface side of the stator side core, and the lead wire leading grooves are independent for each channel of the coil winding. 3. The rotary transformer according to claim 1, wherein the rotary transformer is provided so as to be oriented in the respective connection directions. 4. A lead wire extending from a coil winding of each channel wound on the stator core through a lead wire drawing groove, and has a different length at the beginning and end of winding. Item 4. The rotary transformer according to item 3. The rotary transformer according to claim 1.