JPS59185061A - Tape guide device in vtr - Google Patents

Abstract

PURPOSE:To attain generation of accuracy of linearity of a tape read face easily with high accuracy by forming the tape read face within a plane in parallel with a reference plane and tilting the turning face of a head to the reference plane for a required angle. CONSTITUTION:The tape read face 15 is formed within a plane in parallel with the reference plane 2b and the turning face of a slit 4, i.e., heads 7a and 7b is formed with a slope by a required angle theta to the reference plane 2b. Thus, since the tape read face 15 is formed in parallel with the reference plane 2b, the peocessing is attained easily and the generation of accuracy of linearity is attained with a desired high accuracy. On the other hand, from the standpoint of assembling also, since a cylinder S and guide posts 12, 13 are set perpendicularly to the base, the assembly is attained easily. In video recording and reproduction, a tape T is made run along the tape read face 15 on the circumferential face of the cylinder S in the circumferential direction and the guide posts 12, 13 are stood also in parallel with the cylinder S, the tape runs very stably and proper video recording and reproduction are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape guide device for a VTR in which an upper cylinder and a lower cylinder are fixed and the head is rotatable.

Examples of conventional tape guide devices for VTRs include those shown in FIGS. 1 and 2.

In the figure, the symbol (1) is the upper cylinder, and (2) is the lower cylinder. The upper cylinder (1) is fixed to the lower cylinder (2) with screws via an arm (3), and both (1) (2)
The cylinder S is made up of a single body. Approximately the middle part of cylinder S, that is, both upper and lower cylinders (1) (2
) A slit (4) is formed between them. slit(
4) is formed parallel to a reference plane (bottom surface of the lower cylinder) (2b) perpendicular to the axis (2a) of the lower cylinder (2). (5) is a tape lead surface for guiding tape running, and this tape lead surface (5) is formed to be inclined at a required angle with respect to the reference surface (2b).In other words, with respect to the slit (4). On the other hand, a head disk (6) is disposed inside the cylinder S, and heads (7a) (7b) are fixed to this with the tip portion thereof peeking out from the slit (4).

A shaft (8) is attached to the head disk (6), and this shaft (8) is connected to bearings (9a) (9b).
It is rotatably supported on the lower cylinder (2) via. In this way, the heads (7a) (7b) are constructed as rotary types. (fl is a rotation transmission member that also serves as a stopper, and the head disk (6) is rotationally driven by a rotation drive source (not shown) via this rotation transmission member. (lla) and (llb) are rotary transformers. The cylinder S configured in this way is mounted on a base (not shown) at a required angle of inclination.
The tape T guided to the cylinder S via the guide post (J2) (131) travels diagonally around half the circumference of the cylinder S along the tape lead surface (5). In order to guide the tape T to run in close contact with the circumferential surface of the cylinder S, and to prevent the tape T from twisting in the running portion other than the cylinder S, it is arranged at a predetermined position and inclined at a predetermined angle.Guide boss In addition to the two shown in the figure, a plurality of required pipes are erected.

However, in order to perform proper recording and playback, it is necessary to keep the tape T in close contact with the circumferential surface of the cylinder S and to run it along a prescribed diagonal running route with high precision. For this purpose, strict linearity accuracy of the tape lead surface (5) is required, with an error of 3 μm or less, and the guide post a
It is also necessary to define the upright position and inclination setting angle of the 'a as with high precision.

However, in conventional tape guide devices, the tape lead surface (5) is formed to be inclined at a required angle with respect to the reference surface (2b). It is extremely difficult to process and form.
There was a problem in that strict processing control was required.

In addition, there was a problem in that in order to highly accurately define the positioning and angle setting accuracy of guide boss (09) Q, strict management of component precision and assembly work was required.

This invention was developed by focusing on these conventional problems.The tape lead surface is formed in a plane parallel to the reference surface, and the rotating surface (slip throat) side of the head is aligned with respect to the reference surface. The object of the present invention is to solve the above problem by tilting it at a required angle.

The present invention will be explained below based on the drawings. FIGS. 3 and 4 are diagrams showing embodiments of the present invention. In these figures, the same or equivalent members or parts as in FIGS. 1 and 2 are designated by the same reference numerals, and redundant explanation will be omitted.

First, to explain the configuration, in this invention, the tape lead surface (151) is formed in a plane parallel to the reference surface (2b), and the rotation surface of the slit (4), that is, the head (7a) (7b) is formed on the reference surface (2b). ).In other words, the shaft (8) is inclined at a required angle θ with respect to the axis (2a) of the lower cylinder.

In this way, in this invention, the tape lead surface a9 is the reference surface (
2b), and the tape T is parallel to the cylinder S.
The vehicle runs parallel to the reference surface (2b) on the circumferential surface of the vehicle.

Therefore, the cylinder S is erected upright on the base, and the guide post αUS is also erected upright.

During manufacturing, the tape lead surface (15) is the reference surface (2
It is only necessary to form it parallel to b), so compared to the conventional one, it is directly #! It is possible to easily achieve high accuracy with ease. On the other hand, in this invention, the slit (4)
Although it is necessary to form the slit (4) obliquely, it is easier to obtain the precision of the inclination angle of the slit (4) compared to the precision of the tape lead surface aQ. Comprehensive processing management is easier with this invention.

On the other hand, in the invention of , since the slit (4) is formed to be inclined at a required angle with respect to the axis of the cylinder S, the head (
7a) The amount of protrusion from the circumferential surface of the cylinder S in (7b) changes slightly as the head disk (6) rotates. However, to give a numerical example, the cylinder S has a diameter of 40 φ and is set to about 5 degrees in θ, so the amount of change is extremely small, and the tape T is wrapped around the circumference of the cylinder S only about half a turn. Therefore, this change in head protrusion amount has almost no effect on the operation of the tape T running equalization device.

Next, the assembly and operation will be explained.

Since the tape lead surface α [present] is formed parallel to the reference surface (2b), machining is easy and linearity can be achieved with the desired high accuracy. On the other hand, in terms of assembly, since the cylinder S and the guide post 040 are set upright on the base, ease of assembly is achieved, and good assembly accuracy is also achieved. Therefore, the accuracy of the parts due to the ease of machining of each part, and the good accuracy of assembly due to the ease of assembly combine to significantly reduce the cumulative error of the entire device.

During recording and playback, the tape running system and rotation transmission member α
When the rotary drive source connected to Q is driven, the tape T runs approximately half the circumference of the cylinder S along the tape lead surface (15) in close contact with the head (7a).
) (7b) rotates in the opposite direction, and the head (7a)
(7b) crosses the tape T diagonally. At this time, tape T
The tape lead surface (IQ) is formed with precision, runs along the curve of the cylinder S in its circumferential direction, and the guide post (1au also stands upright parallel to the cylinder S, so it runs extremely stably and properly. recording and playback.

As detailed above, according to the present invention, the tape lead surface is formed in a plane parallel to the reference surface, and the rotating surface of the head is inclined at a required angle with respect to the reference surface, so that the linearity of the tape lead surface can be improved. It is easy to obtain precision, and it is possible to form a groove with high precision through easy machining.

Since the master cylinder and guide post can be set upright in a parallel state, positioning of the guide post is easy. Furthermore, since the tape travels in the same direction as the circumferential direction of the cylinder, combined with the accuracy of each component and the assembly precision described above, tape travel is extremely stable and proper recording is possible. The effect of regeneration can be obtained.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of a tape guiding device in a conventional VTR, FIG. 2 is a perspective view of the same tape guiding device, FIG. 3 is a vertical sectional view of the tape guiding device in a VTR according to the present invention, and FIG. It is a perspective view of the tape guide device same as the above. Upper cylinder 2: Lower cylinder 2a: Lower cylinder axis 2b; Reference plane 4 Ni slit 6: Head disk 7a, 7b: Head 8 F sea y7)
9a, 9b: Bearing 12.13 Ni guide post 15: Tape lead surface S Niji Linda T: Tape Clarion Co., Ltd. agent Ashi 1) Nao Eidai II Ko 1 /,, +53 figure

Claims (1)

[Claims] The upper cylinder and the lower cylinder are fixed, and the head is rotatable, the tip of which is peeked out from a slit formed between the side cylinders, and a tape lead is provided on the circumferential surface of the lower cylinder for guiding tape travel. In a tape guide device for a VTR in which a surface is formed, the tape lead surface is formed in a plane parallel to a reference plane perpendicular to the axis of the lower cylinder, and on the other hand, the rotating surface of the head is formed at a required angle with respect to the reference plane. A tape guide device in a VTR characterized by being tilted at an angle.