JPH0268707A - Rotary head device - Google Patents

Abstract

PURPOSE:To prevent lowering of the performance of recording or reproducing a signal by utilizing a shape memory alloy and controlling a contact condition between a tape and a rotary head according to the kind of tapes. CONSTITUTION:The title device has a fixed cylinder 12 to wind a tape 13 obliquely at a prescribed angle and a travel-guide it and a rotary head 14 to be rotated at a prescribed rotating speed and, simultaneously, to record or reproduce the signal onto the tape 13. Further, the title device is equipped with turning means 16 and 17 to turn the rotary head 14 so that a line to connect the magnetic gap part of the rotary head 14 and the center of a curvature in a magnetic gap part vicinity lengthwise direction can be made to approximately coincide with a normal on a surface on which the tape 13 and rotary head 14 are in contact and with a selecting means 21 to select the kind of the tape 13, and the turning angle of the rotary head 14 is controlled by a control means 22 according to the output of the selecting means 12. Thus, the lowering of the performance of the recording or reproducing of the signal can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rotary head device used, for example, in a magnetic recording device.

BACKGROUND OF THE INVENTION In recent years, rotating head devices have been used in video tape recorders (VTRs).
) has been widely used, and various efforts have been made to improve its performance.

A conventional rotary gutter device will be described below with reference to the drawings.

The conventional rotary head device, as shown in FIG. 4, has a rotation speed of 1000 rpm to 20
The tape is configured to be guided by a rotating cylinder 2 that rotates and oscillates at 00 rpm and a fixed cylinder 3 that does not rotate and oscillate. A lead 4 is provided on the fixed cylinder 3 for the purpose of regulating the position of the magnetic tape 1 during running. The rotating head 5 is held by the rotating cylinder 2 so as to protrude outward from the outer peripheral surface of the rotating cylinder 2 by approximately several tens of microns. Further, 6 is a magnetic head mounting window.

The operation of the conventional rotary head device configured as described above will be described below.

The fixed cylinder 2 swings at 1000 to 200 Orpm, and at the same time, the magnetic tape 1 is given a predetermined tape tension and is run while being wound diagonally around the rotating cylinder 2 and the fixed cylinder 3 at a predetermined angle. A rotary head 5 held by the fixed cylinder 2 so as to protrude outward from the outer peripheral surface of the fixed cylinder 2 by approximately several tens of microns is rotated while contacting the tape 1.

Problems to be Solved by the Invention However, in the above configuration, as the rotating cylinder 2 rotates, an air film 7, which is a thin layer of air, is formed on the circumferential surface of the rotating cylinder 2, as shown in FIG. In order for the tape 1 to run along the lead 4, there is a tape splicing entrance (A), an intermediate position (B), and a tape splicing exit (C).
As the lead portion 4 moves downward, the tape 1 and the rotating head 5 are lowered as shown in FIG.
With respect to the normal m of the surface in contact with The connecting lines n may not match.

Figures 6 and 7 show an example of a conventional rotating device. This is the angle formed with the straight line n.

As this angle α becomes larger, the space loss in the so-called magnetic recording or reproducing process increases, and the signal recording or reproducing performance deteriorates. However, in conventional rotary head devices, there are cases where the value of α is large. Therefore, there was a problem in that signal recording or reproduction performance deteriorated. Moreover, as shown in Figures 6 and 7, for example, the rigidity of the tape changes depending on the type of tape, and the thickness of the tape changes, so there is a problem that the value of α changes depending on the type of tape. was.

In view of the above-mentioned problems, the present invention improves the contact state between the tape and the rotary head according to changes in the type of tape (always keeping α approximately 0°), thereby preventing deterioration in signal recording or playback performance. The present invention provides a rotating head device that prevents this.

Means for Solving the Problems In order to solve the above problems, the rotating head device of the present invention has the following features:
a fixed cylinder for winding the tape diagonally at a predetermined angle and guiding the running; a rotary head that rotates at a predetermined number of rotations and has a magnetic gap section for recording or reproducing signals on the tape; The rotary head is rotated so that a line connecting a magnetic gap portion of the rotary head and a center of curvature in a longitudinal direction near the magnetic gap portion substantially coincides with a normal to a surface where the tape and the rotary head are in contact with each other. The apparatus includes a rotation means for rotating the tape, a selection means for selecting the type of tape, and a control means for controlling the rotation angle of the rotary head in accordance with the output of the selection means.

Operation The present invention controls the head with the above-described configuration and stabilizes the contact state between the tape and the head, thereby reducing space loss and preventing deterioration in signal recording or reproducing performance.

Embodiment Hereinafter, a rotary head device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a rotary head device in one embodiment of the present invention. 11 is a rotating cylinder 12 is a stationary cylinder, 13 is a tape, 14 is a rotating head, 15 is a head mount made of an insulator, and 16 and 17 are a pair of parallel arms made of a shape memory alloy. The arms 16,17 are supported in parallel to the rotating cylinder 11. The arms 16 and 17 have memorized shapes that separate from each other in opposite directions. Arms 16 and 17 are each supplied with a control current from a power source 18, 19 (see Figure 3) to generate heat due to internal resistance, and are deformed by changing the temperature. The head mount 15 connected and supported at the tips of these two arms and the rotary head 14 supported at the tips of the hend mount 15 are configured to rotate as a result of this deformation.

Also, (A) is the tape attached population part in Figure 5, (
B) is the intermediate position in FIG. 5, and (C) is the tape splicing outlet in FIG.

Further, FIG. 2 shows a cross-sectional view of a rotating helad device in one embodiment of the present invention, and the configuration is the same as that in FIG. 1, but
The type of tape 13 is changed.

FIG. 3 shows an overall view of the same embodiment.

21 is a selection button, and the type of tape is selected by this button. Reference numeral 22 denotes a power supply voltage selection means, which applies a voltage to the power supplies 18 and 19 in accordance with the output of the selection button 21. Then, a control current is passed from the power supply 18.19 to the arm 16.17 through the slip ring 23, which is a well-known means, and the temperature is changed by causing heat to be generated by the internal resistance.
6.17, and by this deformation the rotary head 14
However, it is designed to rotate.

The operation of the rotary head device configured as described above will be described below with reference to FIGS. 1, 2, and 3.

First, FIG. 1 shows a rotary head device according to an embodiment of the present invention, and at the position of the tape splicing inlet (A) in FIG. (
As shown in A), the tape 13 and the rotating head 14
Since the value of the angle α between the normal to the surface in contact with the line connecting the magnetic gap portion of the rotary head 14 and the center of curvature in the longitudinal direction near the magnetic gap portion of the rotary head 14 is large, the value of α is large. In order to make the value approximately 0, a control current is passed through the arm 17 from the power supply 19 (see Figure 3), and the temperature of the arm 17 is raised by internal heat generated by the resistance.
7 undergoes a phase transformation and deforms due to superelasticity, and the rotary head 14 and head mount 15 are rotated as shown in FIG. 1(A) so that the value of α becomes approximately 0°. . Next, the first
While moving from the position of the tape attachment entrance (A) in the figure (rotation angle θ - 0°) to the intermediate position (B) (rotation angle θ = 90°) in Fig. 1, the angle α is always approximately 0. Power supply to 19°
(See Figure 3) to set the control current.

Therefore, at the intermediate position (B) in FIG. 1, the tip (magnetic gap portion) of the rotary head 14 is at the position shown in FIG. 1(B). Next, while moving from the intermediate position (B) in Figure 1 (rotation angle θ - 90°) to the tape splicing outlet (C) position (rotation angle θ = 180°) in Figure 1, the angle α is The control current from the power source 19 (see FIG. 3) is set so that the angle is always approximately 0°. Therefore, at the tape splicing exit (C) in FIG. 1, the tip (magnetic gap) of the rotary head 14 is at the position shown in FIG. 1C.

The position of the tape splicing outlet (C) in Fig. 1 (rotation angle θ
= 180°) to the tape attachment entrance (A) in Figure 1 W
Until (rotation angle θ=360”), the tip of the rotary head 14 changes continuously and smoothly.

With the simple configuration shown above, (A
), (B), and (C), the power supply 18° 19 (see Fig. 3) is set so that the angle α of the rotating head 14 is always O゛, and the magnetic gap of the rotating head 14 is adjusted. It is possible to improve the contact state with the tape 13 in the vicinity of the area, and it is possible to keep space loss to a minimum.

However, as shown in FIGS. 6 and 7, for example, when the type of tape changes, the state of contact between the tape and the head also changes. Therefore, the selection means for selecting the tape type (
(see Figure 3), and depending on its output, a power source 18.1
Set 9.

First, by selecting the type of tape with the selection button 21, the power supply voltage means 22 outputs an output according to the type of tape to the power supply 18 through the slip ring 23, which is a well-known means.
．． 19, and arm 16 and arm 17.
By adjusting the shape of the rotary head 14, the locus of rotation of the rotary head 14 is changed depending on the type of tape. arms 16 and 1
By using two of No.7, two of electric 'a18 and No.19 can be made.
Since it can be controlled locally, accuracy and controllability are improved. FIG. 2 shows a case where the tape has a higher rigidity than in FIG.

The operation in FIG. 2 is the same as that in FIG.
As a conventional example, as shown in FIG. 7A, the normal line of the surface where the tape 13 and the rotary head 14 contact, the magnetic gap part of the rotary head 14, and the vicinity of the magnetic gap part of the rotary head 14 are Since the value of the angle α formed with the line connecting the center of curvature in the longitudinal direction is large, in order to make the value of α approximately 0°, the control current is supplied from the power supply 19 (see Figure 3) to the arm 1.
7 to raise the temperature of the arm 17 by internal heat generation due to resistance, the arm 17 undergoes phase transformation and deforms due to superelasticity, and the rotating head 14 and head mounting base 15 are moved to the second position.
It is lowered as shown in Figure (A) so that the value of α becomes approximately 0°. Next, the tape attachment entrance (A) in Figure 2
from the position (rotation angle θ = 0°) to the intermediate position (B) in Figure 2
(Rotation angle θ-90°), the control current from the power source 19 (see FIG. 3) is set so that the angle α is always approximately 0°. Therefore, at the intermediate position (B) in FIG. 2, the tip (magnetic gap) of the rotary head 14 is at the position shown in FIG. 2(B).

Next, from the intermediate position (B) in Fig. 2 (rotation angle θ = 90°) to the position of the tape splicing outlet (C) in Fig. 2 (rotation angle θ-1
The control current from the power supply 19 (see Figure 3) is set so that the angle α is always 0° even when moving to the tape splicing outlet (C) in Figure 1. ), the tip of the rotating hand 14 (magnetic gap) comes to the position shown in FIG. angle θ=180°)
From the position of the tape attachment inlet (A) in Fig. 2 (rotation angle θ-
360°), the tip of the rotary head 14 changes continuously and smoothly.

With the configuration shown above, (A) and (
As shown in B) and (C), the angle α of the rotating hand 14
By setting the power supply 1819 (see Fig. 3) so that Oo is always Oo, it is possible to improve the contact state of the rotary head 14 with the tape 13 near the magnetic gap part, and to keep space loss to a minimum. be able to.

As described above, according to this embodiment, by improving the contact state between the tape and the rotary head according to the type of tape with a simple configuration, it is possible to prevent deterioration in signal recording or playback performance, and furthermore, it is possible to prevent deterioration in signal recording or playback performance. By using two alloys, it is possible to provide a rotary head device that has a simple configuration and high controllability.

Although 16.17 is made of a shape memory alloy in FIG. 1, the same effect can be obtained by using a configuration that utilizes the electrostrictive property of a piezoelectric element that causes distortion when a voltage is applied.

Effects of the Invention As described above, according to the present invention, the line connecting the magnetic gap portion of the rotary head and the center of longitudinal curvature in the vicinity of the magnetic gap portion is a rotating means for rotating the rotary head so as to approximately lose the rotation; a selection means for selecting the type of tape; and a control means for controlling the rotation angle of the rotary head in accordance with an output of the selection means. By providing this, it is possible to improve the contact state between the tape and the rotary head and prevent deterioration in signal recording or reproduction performance.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a rotary head device according to an embodiment of the present invention, FIG. 1(A) is an enlarged view of the tape attachment inlet shown in FIG. ) is an enlarged view of the intermediate position shown in FIG. 6, FIG. 1(C) is an enlarged view of the tape splicing outlet shown in FIG. 6, and FIG. This is a cross-sectional view of different types of tape. FIG. 2(A) is an enlarged view of the tape attachment inlet shown in FIG. 6, FIG. 2(B) is an enlarged view of the intermediate position shown in FIG. 6, and FIG. FIG. 3 is a block diagram of the tape type selection means, FIG. 4 is a front view of a conventional rotary head device, and FIG. 5 is a conventional rotary head device. 6 is a plan view of the main part of the conventional rotary head device, and FIG. 6A is an enlarged view of the tape attachment inlet.
FIG. 6(B) is an enlarged view of the intermediate position, FIG. 6(C) is an enlarged view of the tape splicing outlet, and FIG. A) is an enlarged view of the tape splicing entrance portion, FIG. 7(B) is an enlarged view of the intermediate position, and FIG. 7(C) is an enlarged view of the tape splicing exit portion. 11... Rotating cylinder, 12... Fixed cylinder, 14... Rotating head, 15...
...Installation is on the stand, 16...Arm, 17...
... Arm, 18 ... Power supply, 19 ...
...Power, 21...Selection button, 22...
...Electrical rA voltage selection means. Agent's name Patent attorney Shigetaka Awano Haka 1 name number 1 Roφ no happy 22 Hi 1B, /9 ・-Power supply 2/-F inkstone, shape button? Total - 1, 2 Sukigagen'' Daishiyaku Figure 6 (AI Figure 4 Figure 7 (A) Figure 5 [21 /l-Concave! Tori Shisonta tz-Ichirin Determined Shisonta 14-゛ Concave Atsushi Het' rs ~ Station Shi ↑ Every / Δ, 17- A~A (B) and Cノ (B) (C) // / (B) (C) (C)

Claims (2)

[Claims] (1) A fixed cylinder that wraps the tape diagonally at a predetermined angle and guides its travel, and a fixed cylinder that rotates at a predetermined number of rotations.
and a rotary head having a magnetic gap portion for recording or reproducing signals on the tape, and a magnetic gap portion of the rotary head and the magnetic gap portion with respect to a normal to a surface where the tape and the rotary head are in contact with each other. a rotating means for rotating the rotary head so that lines connecting adjacent centers of curvature in the longitudinal direction substantially coincide with each other; a selection means for selecting the type of tape; and a selection means for selecting the type of tape; A rotary head device comprising: a control means for controlling a rotation angle of the rotary head. (2) The rotating means is made of a shape memory alloy that is attached to the rotating drum and is arranged parallel to the left and right, and that remembers the shape that is deformed in opposite directions.
Claim (1) comprising a book arm and a rotary head connected and carried at the tips of the two arms.
1) The rotary head device described above.