JPH0745944Y2 - Rotating head device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] One aspect of the present invention relates to a rotary head device, and in particular, a cylindrical vertical type for transmitting and receiving a signal between a head provided on a rotary drum and a fixed side. The present invention relates to a structure for mounting a core inside a rotary transformer in an apparatus designed to be carried out by the rotary transformer.

[Outline of device]

The stator core of a vertical rotary transformer incorporated in a head drum device such as a VTR is designed to be bonded to the lower drum.However, if temperature is applied to the cylinder device after bonding, the adhesive contracts, causing deformation of the core or This may cause deterioration of the electrical characteristics of the rotary transformer. In order to prevent such a problem, devise the shape of the adhesive injection groove,
Adhesive injection grooves are provided at three locations along the circumference of the boss of the lower drum at approximately 120 ° intervals, and adhesive is injected into these grooves to fix the stator core.

[Prior Art] In a VTR, a magnetic tape is obliquely wound around a head drum having a rotary head, and the magnetic head is rotated together with the rotary drum to obliquely scan the tape, thereby recording and / or recording in a helical scan system. Also, it is designed to be reproduced. Therefore, it is necessary to send and receive signals between the rotating magnetic head and the circuit on the fixed side. For this reason, for example, a rotary transformer disclosed in Japanese Utility Model Laid-Open No. 62-39201 has been conventionally used. ing.

The rotary transformer includes a horizontal or flat rotary transformer and a vertical rotary transformer as disclosed in the above publication. In the case of a vertical rotary transformer, the stator is attached to the lower drum 1 as shown in FIG. The lower drum 1 is formed with a boss 2 at the center thereof, and the upper surface of the boss 2 is provided with two adhesive injection grooves 3 at positions offset by about 180 ° from each other along the circumferential direction. I am trying to do it. Then, as shown in FIG. 7, the stator 4 of the rotary transformer is fitted and assembled to the boss 2, and the adhesive is injected and fixed from the adhesive injection groove 3.

[Problems to be solved by the invention]

As shown in FIG. 7, the stator 4 of the vertical rotary transformer is installed in the boss 2 of the lower drum 1 as shown in FIG. 6, and the adhesive is injected by the adhesive injection grooves 3 at two positions in the circumferential direction. In this case, after the stator 4 is bonded to the lower drum 1, when the cylinder device is heated, the adhesive contracts. Due to such shrinkage of the adhesive, a force indicated by an arrow in FIG. 8 is generated, and this force causes a deformation of the stator 4.
That is, when the stator 4 is deformed, the electrical characteristics of the rotary transformer are deteriorated, and the stator 4 interferes with the rotor to cause pickpocketing.

The present invention has been made in view of these problems, and a rotation that prevents the stator core or the rotary core inside the cylindrical vertical rotary transformer from being deformed even if a temperature is applied after bonding with an adhesive. It is an object to provide a head device.

[Means for solving problems]

The present invention relates to a rotary head device in which a cylindrical vertical rotary transformer transmits and receives a signal between a head provided on a rotary drum and a fixed side. The inner peripheral surface of the inner stator core or rotor core is fitted and attached to the outer peripheral surface of the boss of the fixed drum or the rotating drum. The present invention relates to a rotary head device characterized in that an adhesive is injected into the injection groove to fix the stator core or rotor core to the boss.

[Action]

Therefore, the stator core or the rotor core inside the cylindrical vertical rotary transformer is attached to the outer peripheral surface of the boss of the fixed drum or the rotary drum in a state of being adhered and fixed at three locations in the circumferential direction. Even if contraction occurs due to the applied temperature, the circumferential force generated by the contraction is dispersed. Therefore, the stator core or the rotor core is prevented from being deformed into a non-circular shape,
Alternatively, the non-circular deformation of the stator core or the rotor core due to the contraction of the adhesive is reduced.

〔Example〕

FIG. 5 shows the structure of a rotary head device according to an embodiment of the present invention.
And a lower drum 12 are included. The upper drum 11 is a rotating drum, and the lower drum 12 is a fixed drum. A magnetic head 13 is attached to the upper drum 11 so as to face the outer peripheral surface thereof, and is fixed to a rotating disk 14. The rotating disk 14 is fixed to the main shaft 15 by a nut 16. The main shaft 15 is rotatably supported by the lower drum 12 by a pair of upper and lower bearings 17, 18.

This rotary head device includes a rotary transformer 20 for exchanging signals between the magnetic head 13 supported by the rotary drum 11 and the fixed side. The rotary transformer 20 is composed of a stator 21 and a rotor 22.
The rotor 22 is supported on the inner peripheral surface of the rotating disk 14. On the other hand, as shown in FIGS. 1 and 2, the stator 21 is attached to a boss 23 provided so as to project in the central portion of the lower drum 12. Moreover, the adhesive injection grooves 24 are formed on the upper surface of the boss 23 at intervals of 120 °, and the stator 21 is fixed to the boss 23 by the adhesive injected into these grooves 24.

Thus, in the rotary head device according to the present embodiment,
Adhesive injection grooves 24 are formed at three positions at 120 ° intervals in the circumferential direction on the upper surface of the mounting portion 23 of the stator 21 of the vertical rotary transformer 20 of the lower drum 12. Adhesive injection groove
The thickness of 24 is made as small as possible without hindering the bonding work, and the width of the adhesive injection groove 24 is designed to maintain the adhesive strength.

Generally, the adhesive for fixing the stator core 21 is formed by an injection groove.
Shrinks when heated after being injected into 24 and fixed. According to the conventional two adhesive injection grooves in the circumferential direction, the stator core is deformed, the gap between the rotor and the stator of the rotary transformer is changed, and the electrical characteristics of the rotary transformer are deteriorated. There is a problem that a pickpocket is generated between the stator and the rotor. However, in this embodiment, the adhesive injection grooves 24 are provided at three positions at 120 ° intervals to disperse the force generated when the adhesive contracts,
The deformation of the stator core 21 is reduced. Therefore, the above-mentioned problem is solved.

[Application Example] Although the present invention has been described above with reference to the illustrated embodiment, the present invention is not limited to the above embodiment, and various modifications can be made based on the technical idea of the present invention. For example, in the above embodiment, the stator core inside the rotary transformer is fitted and attached to the boss of the lower drum. However, instead of such a structure, the rotor core inside the total transformer is replaced with the boss of the rotary drum. It is also possible to fit and attach the rotor core to the boss and to fix the rotor core to the boss with adhesive at three locations at 120 ° intervals along the circumferential direction.

[Effect of device]

As described above, according to the present invention, the inner peripheral surface of the stator core or the rotor core inside the cylindrical vertical rotary transformer is fitted to the outer peripheral surface of the boss of the fixed drum or the rotating drum, and the outer peripheral surface of the boss is circular. 12 along the circumference
An adhesive injection groove is provided at an interval of 0 °, and the adhesive is injected into the injection groove to bond and fix the stator core or the rotor core to the boss.

Therefore, according to such a configuration, even if the rotary head device is heated and the adhesive contracts after the stator core or the rotor core of the cylindrical vertical rotary transformer is bonded, the adhesive is applied in the radial direction of the cylindrical rotary transformer. The force will be distributed, which prevents or reduces non-circular deformation of the stator core or rotor core. Therefore, it is possible to prevent a change in the electrical characteristics of the rotary transformer and to avoid a slip between the stator and the rotor.

[Brief description of drawings]

FIG. 1 is a plan view of a lower drum of a rotary head device according to an embodiment of the present invention, FIG. 2 is a perspective view showing how a stator of a rotary transformer is attached to the lower drum, and FIG. 4 is a plan view of the lower drum, FIG. 4 is a plan view of the lower drum showing the force generated by the contraction of the adhesive, and FIG.
FIG. 6 is a vertical sectional view of the assembled rotary head device, FIG. 6 is a plan view of a conventional lower drum, FIG. 7 is a plan view with the stator attached, and FIG. 8 is deformation due to contraction of an adhesive. FIG. 3 is a plan view of the lower drum showing FIG. The names of the main parts in the drawings are as follows. 11 …… Upper drum (rotating drum) 12 …… Lower drum (fixed drum) 13 …… Magnetic head 20 …… Rotary transformer 21 …… Stator 22 …… Rotor 23 …… Boss 24 …… Adhesive injection groove

Claims (1)

[Scope of utility model registration request] 1. A rotary head device in which a cylindrical vertical rotary transformer transmits and receives signals between a head provided on a rotary drum and a fixed side, wherein the cylindrical vertical rotary transformer is provided. The inner peripheral surface of the inner stator core or rotor core is fitted and attached to the outer peripheral surface of the boss of the fixed drum or the rotating drum, and the adhesive injection grooves are provided on the outer peripheral side of the boss along the circumferential direction at intervals of about 120 °. Is provided, and an adhesive is injected into the injection groove to bond and fix the stator core or the rotor core to the boss.