JPH03127314A - Position adjusting device for fixed head of vtr - Google Patents

Abstract

PURPOSE:To adjust the position of a head without changing right and left wrap angles of the head by forming first and second long grooves along a loca which are depicted by first and second guide pins at the time of moving first and second tape guides with the angle of entrance and that of exit of a tape kept. CONSTITUTION:A first reference line l which is parallel with the tape running direction between a fixed head 4 and a first tape guide 1 and passes the center of the first tape guide 1 is supposed, and a second reference line (m) which is parallel with the tape running direction between a second tape guide 2 and the fixed head 4 in the reference position and passes the center of the second tape guide is supposed. A first virtual triangle connecting tape guides 1 and 2 and a first guide pin 8 is supposed, and the direction of a first long groove 6 is set based on the locus which is depicted by one apex at the time of moving two other apexes along the first reference line l and the second reference line (m). In the same manner, a second virtual triangle connecting tape guides and a second guide pin G is supposed and the direction of a second long groove 7 is set based on the locus depicted by one apex. Thus, the position is adjusted without changing right and left wrap angles of the head.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a VTR (video tape recorder) that adjusts the position of the fixed head in order to maintain a constant distance between the fixed head and other parts such as a rotating head. This invention relates to a device for adjusting the position of a fixed head of a recorder.

[Summary of the Invention] The present invention provides a fixed head that is disposed between a first tape guide and a second tape guide, with which the tape guided by these guides comes into contact, and a head holding member of the fixed head that has first and second long grooves. A fixed head position adjusting device for a VTR includes first and second guide pins arranged in the first and second long grooves, respectively, wherein the first tape guide and the fixed head at a reference position are arranged in the first and second long grooves. The first ! which is parallel to the tape running direction between and which passes through the center point of the first tape guide. Assuming a reference line, a second reference line that is parallel to the tape running direction between the second tape guide and the fixed head at the reference position and passing through the center point of the second tape guide; Assume a first virtual triangle connecting the first tape guide, the second tape guide, and the first guide pin, and the two vertices of this first virtual triangle are the first reference line and the second
The direction of the first long groove is set based on the locus drawn by other vertices when moving along the reference line, and the first tape guide, the second tape guide, and the second guide pin are connected to each other. Assuming a second virtual triangle connecting the two vertices, the second By setting the direction of length Fr4, the fixed head guided by the first and second long lines is displaced without changing the tape incidence angle and tape ejection angle at the reference position, so the left and right wrap angle of the head can be adjusted. The position is adjusted without changing.

[Prior Art] For example, there is a VTR that records video signals on a tape with a rotating head and audio signals with a fixed head and separate heads. This type of VTR uses a rotating head (
A fixed head position adjustment device is provided to position the fixed head at a position a predetermined tape length from the rotating drum.

In the conventional fixed head position adjustment device, as shown in FIG. 1.2, the tape 3 from the rotating drum IO is guided. A fixed head 4 is arranged between the first and second tape guides 1 and 2, and the tape 3 is in contact with the fixed head 4 by a predetermined wrap angle (a, b). This fixed head 4 is held by a head holding member 5, and this head holding member 5 is formed with first and second lengths M6 and 7. The first and second long grooves 8 and 9 extend perpendicularly to the center line C of the fixed head 4, and the first and second long grooves 6.7 are provided with the first and second long grooves, respectively. A guide pin 8.9 is arranged. The first and second guide pins 8°9 are fixed to the chassis, and the head holding member 5 and fixed head 4 are displaced while being guided by the first and second long grooves 6°7 (Utility Model Publication No. 63-2992). (see publication)
. Then, number one! By sliding the head holding member 5 in the direction of the arrow while being guided by the second long grooves 6 and 7, the tape length from the rotating drum IO to the fixed head 4 is varied, and the tape length from the rotating drum IO is the reference value. The head holding member 5 is fixed to the chassis at a certain L position.

[Problem to be solved by the invention, m] However, in the above configuration, when the fixed head 4 is slid, the tape incidence angle a and the tape ejection angle shown in FIG. This causes inconveniences such as angles (a, b) fluctuating and interfering with signal transmission.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a fixed head position adjusting device for a VTR that can adjust the tape length from other parts without changing the left and right wrap angles of the head.

[Means for Solving the Problems] A fixed head position adjusting device for a VTR according to the present invention for achieving the above object includes first and second tape guides provided on the chassis for guiding the running of the tape. A fixed head that contacts the tape is disposed between the first and second tape guides, a head holding member that holds the fixed head is provided with first and second long grooves, and the chassis has first and second long grooves. a guide pin is provided, the first and second guide pins are arranged in the first and second long grooves, and the head holding member is moved while being guided by the first and second long grooves. V adjusting the position of the fixed head
In a TR fixed head position adjustment device, a first reference line is assumed that is parallel to the tape running direction between the first tape guide and the fixed head at a reference position and passes through the center point of the first tape guide. Assuming a second reference line parallel to the tape running direction between the second tape guide and the fixed head at the reference position and passing through the center point of the second tape guide, Assume a first virtual triangle connecting the tape guide, the second tape guide, and the first guide pin, and the two vertices of this first virtual triangle are the first base line and the second base line. The direction of the first length) 14 is set based on the locus drawn by the other vertices when moving along 91tfA, and the direction of the first tape guide, the second tape guide, and the second guide pin is set. Assuming a second virtual triangle that connects the Long 11-! The direction is set.

[Operation] If the fixed head and head holding member are fixed and the second tape guide and the first and second guide pins are movable, the first and second long grooves are arranged to When the first and second tape guides move along the first reference line and the second reference line while maintaining the tape ejection angle and the tape ejection angle, the first and second guide pins move along the respective trajectories. Therefore, movement of the fixed head guided by the first and second long grooves It does not change the tape incidence angle and the tape exit angle.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

Embodiments of the invention are shown in FIGS. 1-4.

FIG. 1 shows a schematic configuration diagram of a fixed head position adjustment device. In FIG. 1, a first tape guide 1.2 and a second tape guide 1.2 are installed upright on a chassis (not shown) at positions separated by a distance. A rotating drum is provided, and a rotating head for recording and reproducing video signals is attached to the rotating drum.

The tape 3 guided from the rotating drum is guided by first and second tape guides 1.2.

A fixed head 4 is arranged between the first and second tape guides 1 and 2, and the tape is in contact with the fixed head 4 at a predetermined wrap angle (a, b). This fixed head 4 records and reproduces audio signals on the tape 3, and the fixed head 3 is held by a head holding member 5. This head holding member 5 is formed with first and second lengths RI￥6.7, and within these first and second lengths ###6,7 are first and second guides fixed to the chassis. Pin 8.9 is inserted. The head holding member 5 is movable along the first and second long grooves 6 and 7 while being regulated by the first and second guide pins 8°9, as shown by the dashed line in FIG. It is configured.

FIGS. 2 to 4 sequentially illustrate a method for determining the direction of the first and second long grooves 6.7. As shown in FIG. 2, the fixed head 4 is positioned at a reference position where the left and right wrap angles are at desired angles (a, b). Then, a first reference line Q, which is parallel to the tape running direction between the first tape guide L and the fixed head 4 at the reference position and passes through the center point of the first tape guide I, is connected to the second tape guide 2. and a second reference line m that is parallel to the tape running direction between the fixed head 4 at the reference position and passes through the center point of the second tape guide 2.
Assume respectively. The first reference line 2 and the second reference line m are line AB and line CB, respectively, where B is the intersection point.

Next, as shown in FIG. 3, the center of the first tape guide 1, the center of the second tape guide 2, and the first guide pin 8
Assume a first virtual triangle RI connecting the centers of , and a second virtual triangle connecting the center of the first tape guide l, the center of the second tape guide 2, and the center of the 72nd guide pin 9. Assume a virtual triangle.

Finally, as shown in FIG. 4, the vertices (A, C) formed by the center of the first tape guide l and the center of the second tape guide 2 of the first virtual triangle D1 are aligned with the first reference line e. The longitudinal direction of the first long groove 6 is determined based on the locus drawn by the apex formed by the center of the first guide pin 8 when the first guide pin 8 is moved along the second reference line m. Also, a second virtual triangle.

The longitudinal direction of the second long groove 7 is determined based on the locus drawn by the apex E formed by the center of the second guide pin 9 when the second guide pin 9 is moved in the same manner as described above.

In the above configuration, the fixed head 4 and the head holding member 5
is fixed, and conversely, the first and second tape guides 1.2
Assuming that the first and second guide pins 8°9 are movable, the tape incidence angle and tape exit angle are maintained, that is, along the first reference line e and the second reference line m. 1st
The directions of the first and second lengths #+78 and 9 are set by the loci drawn by the first and second guide pins 8.9, respectively, when the second tape guide 1.2 moves. Therefore, the movement guided by the first and second long grooves 8.9, which is the opposite actual movement of the fixed head 4, does not change the tape incidence angle a and the tape exit angle Even if the left and right wrap angles move, the left and right wrap angles maintain the left and right wrap angles (a, b) at the reference position. Then,
If the fixed head 4 is moved to a position where the tape length from the rotating drum to the fixed head 4 becomes the reference value, and the head holding member 5 is fixed to the chassis at this position, the fixed head 4 is fixed.
The position is adjusted without changing the left and right wrap angles (a, b).

[Effects of the Invention] As described above, according to the present invention, a fixed head is disposed between the first and second tape guides, with which the tape guided by these comes into contact, and the head holding member of the fixed head is A fixed head position adjusting device for a VTR comprising first and second long grooves and first and second guide pins disposed in the first and second long grooves, respectively.
Assuming a first reference line that is parallel to the tape running direction between the tape guide and the fixed head at the reference position and passes through the center point of the first tape guide, Assuming a second reference line that is parallel to the tape running direction between the fixed heads and passing through the center point of the second tape guide, the first tape guide, the second tape guide, and the second tape guide ! Assuming a first virtual triangle that connects the guide pin of Set the direction of the first long groove, assume a second virtual triangle connecting the first tape guide, the second tape guide, and the second guide pin, and Since the direction of the second long groove is set based on the trajectory drawn by the other vertices when one vertex moves along the first reference line and the second reference line, the direction of the second long groove is Since the fixed head is displaced without changing the tape incidence angle and tape ejection angle at the reference position, the position can be adjusted without changing the left and right wrap angle of the head.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, FIG. 1 is a schematic configuration diagram of a fixed head position adjustment device, and FIGS. 2 to 4 are diagrams each illustrating a method for determining the direction of the long groove. , FIG. 5 is a schematic diagram of a conventional fixed head position adjustment device. ! ...First tape guide, 2...Second tape guide, 3...Tape, 4...Fixed head, 5...
Head holding member, 6...first long poem, 7...second length 7i'4.8...first guide pin, 9...second
guide pin, Q, first reference line, m...second reference line, D,...first virtual triangle, D. -Second virtual triangle. Figure 2! ---The third Sakutan-sama Ushin's direction Moeoku Shiba Yo; Mugi E-ken B8 Gou-ma 3rd figure Nagamizo direction te 22: Kabuto Gozuke Banquet B Monthly Painting 4 figure Guest Eneda Tsunaa Kozu (Fukumi Mi) Figure 5

Claims (1)

[Claims] (1) First and second tape guides for guiding the running of the tape are provided on the chassis, a fixed head that contacts the tape is arranged between the first and second tape guides, and the fixed head is held. The head holding member is provided with first and second long grooves, and the chassis is provided with first and second guide pins, and the first and second guide pins are inserted into the first and second long grooves. In the fixed head position adjusting device for a VTR, the fixed head position adjustment device for a VTR adjusts the position of the fixed head by moving the head holding member while guiding it in the first and second long grooves, the first tape guide and the reference position. Assuming that a first reference line is parallel to the tape running direction between the fixed heads at , and passes through the center point of the first tape guide, the tape between the second tape guide and the fixed head at the reference position is Assume a second reference line that is parallel to the running direction and passes through the center point of the second tape guide, and connects the first tape guide, the second tape guide, and the first guide pin. Assuming a first virtual triangle, when the two vertices of the first virtual triangle move along the first reference line and the second reference line, the first long groove is based on the locus drawn by the other vertices. and assume a second virtual triangle connecting the first tape guide, the second tape guide, and the second guide pin, and set the direction of the second tape guide.
VT characterized in that the direction of the second long groove is set based on the trajectory drawn by the other vertices when two vertices of the virtual triangle move along the first reference line and the second reference line.
R fixed head position adjustment device.