JPH0821509B2 - Coaxial rotary transformer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coaxial rotary transformer for transmitting and receiving signals between a rotary head used in a video tape recorder and the like and a fixed side.

2. Description of the Related Art Conventionally, as shown in FIGS. 10 to 12, this type of coaxial rotary transformer has a plurality of signal coil circumferential grooves 2 on the outer peripheral surface of a cylindrical core 1 and the signal coil circle. A short ring circumferential groove 3 and several vertical grooves 4 are provided in the height direction between the circumferential grooves 2. The signal coil circumferential groove 2 is provided with a signal coil 5, and the short ring circumferential groove 3 is provided with a short ring. Winding bare wire or insulation-coated wire 6 for 1 turn or more, signal coil 5
The outer side coil (not shown) is covered on the inner side coil by pulling out the lead wire through the vertical groove 4.

This short ring is adopted in order to prevent mutual interference between the signal coils 5 and prevent generation of noise and change in inductance to obtain a rotary transformer having stable characteristics.

Problems to be Solved by the Invention In general, a rotary transformer requires the widest facing area of the surfaces facing each other in view of the performance of the device. Therefore, the vertical groove 4 and the circumferential groove 2, of the cylindrical core 1, The groove width of 3 is
On the contrary, it is formed as narrow as possible.

For this reason, it is necessary to twist and match each other in the narrow circumferential grooves 2 and 3 and the vertical groove 4 to join them by soldering, etc., and the solder scatters during soldering work, or an extra fine iron tip is used. Therefore, the soldering time becomes long. In addition, after cutting the extra wire after soldering, and repeating this process as many times as necessary, workability is extremely poor, and since it is performed in a narrow groove, the reliability of the joint decreases as the number increases. Met.

Means for Solving the Problems In order to solve the problems, according to the present invention, a plurality of signals in which signal coils facing each other are wound on the inner and outer peripheral surfaces of a cylindrical core that closely opposes each other inside and outside. An inner coil and an outer coil each having a coil circumferential groove are provided, and a short ring circumferential groove is provided between the signal coil circumferential grooves of the cylindrical core of the inner coil. A vertical groove having a deeper groove than the circumferential groove for the short ring is provided in the circumferential groove, and a ring-shaped wire having a diameter larger than the core outer diameter is mounted in the circumferential groove for the short ring. The short ring coil is pressed into the vertical groove provided in the groove and is housed in the short ring circumferential groove.

Action With the above configuration, since the ring shape is previously twisted or soldered with a round bar or the like, mechanization of the work is easy and the workability is extremely improved.

Further, since the cylindrical core is housed in the circumferential groove for the short ring in a ring shape, the mechanization of insertion and pressing is easy and stable storage is realized, and the quality and workability are excellent.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings 1 to 9.

First, in FIGS. 1 to 4, 7 is an inner side coil, 8 is an outer side coil, and the inner side coil 7 is concentrically incorporated in the outer side coil 8. The inner coil 7 has a plurality of signal coil circumferential grooves 10 on the outer peripheral surface of a cylindrical core 9, and a short ring circumferential groove 11 between the signal coil circumferential grooves 10 in the height direction. Providing several vertical grooves 12 slightly deeper than both circumferential grooves 10, 11, the signal coil 13 is wound around the signal coil circumferential groove 10,
A short ring coil 14 in which a conductive material such as a bare wire, a covered wire or a metal foil is formed in a ring shape is housed in each of the circumferential grooves 11 for the short ring, and the lead wire of the signal coil 13 is a vertical groove.
It is drawn out through 12 and is connected to the terminal 16 of the terminal plate 15 which is connected to the lower end of the cylindrical core 9. As shown in FIG. 5, the short ring coil 14 includes a round bar 23 and a conductive material 14
By winding a and connecting the intersecting portions by soldering or welding, a ring-shaped short ring coil 14 having a diameter slightly larger than the outer diameter of the cylindrical core 9 as shown in FIGS. 6 and 7,
As shown in FIG. 8, this is fitted in a position corresponding to the circumferential groove 11 for the short ring of the cylindrical core 9 so that the cylindrical core 9
It is pressed in at one or more parts of the vertical groove 12 of, and the diameter of the short ring coil 14 is reduced to reduce the circumferential groove for the short ring 11.
It is housed and fixed inside as shown in FIG.

Further, the outer coil 8 is provided with a plurality of signal coil circumferential grooves 18 and several vertical grooves 19 on the circumferential surface of the cylindrical core 17.
A signal coil 20 is wound around the signal coil circumferential groove 18, and a lead wire of the signal coil 20 is connected to a terminal 22 of a terminal plate 21 coupled to the upper end of the cylindrical core 17 through a vertical groove 19. Has been done.

The signal coils 13 and 20 of the inner coil 7 and the outer coil 8 are combined so as to face each other.

As described above, according to the coaxial rotary transformer of the present invention, since the wire rod of the short ring is preliminarily processed into a ring shape and is housed and fixed in the circumferential groove for the short ring, it is bonded in a narrow groove as in the conventional case. Without machining, it is easy to mechanize each work from processing the short ring to storing it in the groove, and the reliability of the joint is stable, the reliability is high, and the work man-hours are greatly reduced. The effect is very large.

Further, according to the present invention, it is possible to deform the short ring coil so that it can be easily attached to the circumferential groove for the short ring, and it is possible to stably stabilize the storage because it is very difficult to stably store it against variations. It can be stored and fixed.

[Brief description of drawings]

FIG. 1 is a perspective view of a coaxial rotary transformer according to an embodiment of the present invention, FIG. 2 is a sectional view of the same, FIG. 3 is a perspective view of a coil portion on the inner side thereof, and FIG. FIG. 5 is a perspective view showing a state in which a short ring coil is formed,
Figures and 7 are perspective views of the short ring coil, and Figure 8 and
FIG. 9 is an explanatory view showing the incorporation of the short ring coil, and FIG. 10 is a perspective view of a conventional inner coil,
11 and 12 are front views of the main part. 7: Inner coil, 8: Outer coil, 9
…… Cylindrical core, 10 …… Signal coil circumferential groove, 11 …… Short ring circumferential groove, 12 …… Vertical groove, 13 …… Signal coil, 14 …… Short ring coil, 15 …… Terminal plate , 16 ...
… Terminals, 17 …… Cylindrical core, 18… Circular groove for signal coil, 19… Vertical groove, 20… Signal coil.

Claims (1)

[Claims] 1. An inner side coil and an outer side, each of which has a plurality of signal coil circumferential grooves formed by winding opposing signal coils on the inner and outer peripheral surfaces of a cylindrical core that closely opposes the inner and outer sides. A coil is provided, and a short ring circumferential groove is provided between the signal coil circumferential grooves of the cylindrical core of the inner coil, and a groove deeper than the short ring circumferential groove is provided in the short ring circumferential groove. With a vertical groove with a ring-shaped wire rod that is larger than the outer diameter of the core in the circumferential groove for the short ring, press the short ring coil into the vertical groove provided in the circumferential groove for the short ring. A coaxial rotary transformer housed in the circumferential groove for a short ring.