JPH0548251Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a positioning device for a rotary head device used in an auto-reverse tape recorder.

(Prior art and its problems) Conventionally, auto-reverse tape recorders have a rotary head device (so-called rotary head device) that rotates 180 degrees in conjunction with the reversal operation of each tape running direction to switch tape tracks. bilateral head) is well known.

Fig. 4 shows an example of a conventional rotary head device, in which 1 is a chassis for mounting a rotary head mechanism, 2 is rotatably mounted on the chassis 1 with a shaft 3, and a recording/reproducing head is attached to the chassis 1. RPH,
This is a head support member to which an erasing head EH and a tape guide 4 are attached.A positioning engagement arm 2a is attached to the head support member 2 so as to rotate together with the head support member 2. 5 and 6 engage with the engaging arm 2a at the rotational position of the head support member 2 corresponding to each tape running direction, and the tape T of the magnetic head is engaged with the engaging arm 2a.
This is an azimuth adjustment screw for adjusting the azimuth angle with respect to the protrusion 1 formed on the side of the chassis 1.
They are screwed together with springs 5a and 6a attached to a and 1b, respectively.

As shown in FIG. 5, a pinion 3a is attached to the lower end of the rotating shaft 3 of the head support member 2, and is constantly engaged with a sector gear 7 which is reversely operated by a tape running direction switching mechanism (not shown).
This fan-shaped gear is configured to selectively take a reversal position according to each tape running direction by a reversing spring 8, and at this time, the rotation stroke of the fan-shaped gear 7 is set to be larger than the rotation stroke of the head support member 2. By doing so, the engagement arm 2a of the head support member 2 can be pressed against the tip of the azimuth adjustment screw corresponding to its rotational position by the elasticity of the reversing spring 8. This prevents rattling between the engaging arm 2a and the azimuth adjustment screw 5 or 6 with which it comes into pressure contact, allowing accurate azimuth adjustment.

That is, when the tape T is running in the direction of arrow A as seen in FIG. By adjusting the screw 5, the azimuth in the tape running direction can be adjusted.

When the tape running direction is reversed and switched to the direction of arrow B, the head support member 2 is rotated counterclockwise and the engaging arm 2a is pressed against the azimuth adjustment screw 6. Azimuth adjustment in the tape running direction can be made.

However, according to the conventional rotary head device described above, the positioning of the head support member 2 is performed by the engaging arm 2a.
This is done by abutting the tips of the azimuth adjustment screws 5 and 6, and since the head support member 2 is instantly reversed with a relatively strong force by the reversing spring 8, it can be used for a long period of time. This causes wear on the tip of the azimuth adjustment screw. Usually, the azimuth adjustment screw has a thin, pointed tip or a curved surface to prevent errors depending on the adjustment position, and is designed to make point contact with the engaging arm 2a. However, it has the disadvantage that it is more prone to wear, deformation, etc., and is more likely to cause azimuth deviation.

Also, in order to increase the wear resistance of the tip of the azimuth adjustment screw, it was considered to form the tip into a planar shape and use this surface to receive the engagement arm, but the azimuth adjustment screw could be moved If the azimuth was adjusted using the same method, surface contact could no longer be obtained, and the problem could not be solved.

(Objective of the invention) It is an object of the present invention to provide a rotating head device which eliminates the above-mentioned drawbacks and which does not cause azimuth deviation due to wear, deformation, etc. of the azimuth adjustment screw even after long-term use.

(Summary of the invention) In a rotary head device that rotates 180 degrees according to the tape running direction to switch tape tracks, the tip of the azimuth adjustment screw that positions each rotational position according to the tape running direction is By movably attaching a sleeve that has an engagement surface that makes surface contact with the engagement arm of the head support member, even if the relative position between the azimuth adjustment screw and the head support member changes, the engagement arm can always be moved to the surface of the sleeve. This is a new tape recorder head device that prevents wear and deformation of the azimuth adjustment screw.

(Embodiment) FIG. 1 is a plan view showing an embodiment of the head device of an auto-reversing tape recorder according to the present invention, and the same parts as those of the above-mentioned conventional example are given the same reference numerals and the explanation thereof will be omitted.

As shown in the figure, the configurations of the chassis 1, head support member 2, recording/reproducing head RPH, erasing head EH, tape guide 4, etc. are the same as in the conventional example, and the head support member 2 is reversed according to the tape running direction. The configuration is similar to the conventional example shown in FIG.
(a) This is performed by a fan-shaped gear 7 that reverses in conjunction with a tape running direction switching mechanism (not shown) and a reversing spring 8. The structure of the azimuth adjustment screw that abuts the engagement arm 2a to determine the position at each rotational position of the head support member 2 is different.

The protrusions 1a and 1b formed on the chassis 1 include
Azimuth adjustment screws 10 and 11 are screwed together via springs 12a and 12b, respectively, for positioning the rotational position of the head support member 2 according to the tape running direction. The springs 12a and 12b are provided to prevent the azimuth adjustment screws 10 and 11 from wobbling, but the engagement arm 2a of the head support member 2 is pressed by the elasticity of the reversing spring 8, thereby preventing the azimuth adjustment screws 10 and 11 from shaking. It is not necessarily indispensable as it can prevent scorching.

As is clear from FIG. 2 showing the cross section of the azimuth adjustment screws 10 and 11, spherical projections 10a and 11a are formed at their tips, and these projections 10a and 11a have cylindrical Shaped sleeves 13, 14 are movably mounted.

These cylindrical sleeves have engaging surfaces 13a and 14 on one end that abut against the engaging arms of the head support member 2.
Spherical receiving holes 13b and 14b, which are slightly larger than the protrusions 10a and 11a of the azimuth adjustment screws 10 and 11, are formed on the other end side, and the azimuth adjustment screws 10 and 14b are respectively formed in these receiving holes 13b and 14b.
By fitting the eleven spherical protrusions 10a and 11a, a universal joint is constructed and is movably attached so that it can be tilted in any direction.

Also, the receiving holes 13b, 14 of the sleeves 13, 14
The spherical protrusion 10a, 1 of the azimuth adjustment screw is inside b.
1a, the receiving holes 13b and 14b are spherical and the openings are smaller than the diameters of the spherical protrusions 10a and 11a. By forming grooves 13c, 14c, etc. in the sleeve shown by the dashed dotted line, and press-fitting the spherical protrusions 10a, 11a, the sleeve can be fitted while pushing the lower side of the sleeve apart.

Since the head device of the present invention is constructed as described above, the head support member 2 is rotated according to the tape running direction, and its engaging arm 2a is attached to the sleeves 13, 14 at the tips of each azimuth adjustment screw 10, 11. When pressed by the elasticity of the reversing spring 8, the engaging arm 2a and the azimuth adjusting screw 10, as shown in FIG.
Even if 11 is not vertical, the sleeve 1 is attached to the engaging arm 2a.
3 and 14 are tilted so that their engagement surfaces 13a and 14a are in surface contact, and the engagement arm 2a can always be received in a flat surface without being received at the edge of the sleeve, that is, in point contact. Therefore, as a result of azimuth adjustment, even if the engaging arm 2a and the azimuth adjustment screw are no longer perpendicular and the engaging arm is received diagonally, it can always be received on the plane of the sleeve. .

This can prevent wear and deformation of the azimuth adjustment screw during long-term use. Furthermore, since the azimuth adjustment screw and the sleeve are connected by a spherical universal joint, the screw can receive force in the same manner no matter which direction it is applied, and it is difficult for uneven wear to occur.

(Effects of the invention) As described above, according to the head device of the present invention, in a rotary head device that rotates 180 degrees according to the tape running direction and switches tape tracks, the head device according to the present invention By movably attaching a sleeve having an engagement surface that makes surface contact with the engagement arm of the head support member to the tip of the azimuth adjustment screw that determines each rotational position, the connection between the azimuth adjustment screw and the head support member can be adjusted. Even if the relative position changes, the engagement arm is always received by the engagement surface of the sleeve, that is, the flat surface, so even if the angle between the azimuth adjustment screw and the engagement arm changes as a result of azimuth adjustment, the engagement remains When the engagement arm contacts the azimuth adjustment screw, the sleeve tilts its engagement surface to the position where it abuts the engagement arm, so the engagement arm can always be received on a flat surface, which is different from conventional point contact support. It is possible to provide a highly durable head device that is free from wear and deformation compared to azimuth adjustment mechanisms, and which does not cause azimuth deviation even after long-term use.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the head device of the present invention, FIG. 2 is a partial sectional view for explaining the structure of the azimuth adjustment screw, and FIG. 3 is a plan view for explaining the operation of the head device of the present invention. FIG. 4 is a plan view showing an example of a conventional head device, and FIG. 5 is a plan view showing a rotation mechanism of the head device. Explanation of symbols: 1... Chassis, 2... Head support member, 2a... Engaging arm, 10, 11... Azimuth adjustment screw, 10a, 11a... Spherical projection, 1
3, 14...Cylindrical sleeve, 13a, 14a...
...Engaging surface, 13b, 14b...Receiving hole.

Claims (1)

[Scope of utility model registration request] A head support member that rotates in response to reversal of the tape running direction and switches the magnetic head to a track corresponding to each tape running direction, and an engagement arm that rotates the head support member together with the support member to run the tape. A rotary head device comprising a pair of azimuth adjustment screws for positioning a rotational position according to a direction, a spherical protrusion is formed at the tip of each azimuth adjustment screw, and the spherical protrusion has one end. A sleeve having an engagement surface that makes surface contact with the engagement arm is movably attached to the sleeve with a spherical receiving hole slightly larger than the spherical protrusion formed at the other end. When positioning the head support member at each rotational position according to the tape running direction using the azimuth adjustment screw, the engagement surface of the sleeve is always brought into surface contact with the engagement arm. Features of the tape recorder head device.