JPH01307912A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To simplify the constitution and to improve the assembly accuracy by providing a ball bearing with a shaft and a ball bearing, respectively on a rotation axis of a rotary head mechanism. CONSTITUTION:The title device is constituted so that a ball bearing 5 with a shaft and a ball bearing 2 are provided, respectively on a rotation axis of a rotary head mechanism. In this state, the upper drum 1 comes into contact with an inner ring of the ball bearing 2, and the part between an outer ring of the ball bearing 2 and a bearing housing of the lower drum 3 is not fixed, therefore, it is in a steady pre-load in which a pre-load by a coil spring 4 is always applied. Also, the lower part of the ball bearing 5 with a shaft consists of a direct bearing with a shaft, therefore, even if a rotor 6 of a motor is removed, no pre-load variation occurs. In such a way, a rotary head assembly can be made small in size and light in weight due to a fact that a transformer base is unnecessary, etc., and the assembly accuracy can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a helical scan type magnetic recording and reproducing apparatus having a structure in which a tape-shaped recording medium is pulled out from a cassette and wound around a rotating magnetic head.

[Prior Art] Fig. 2 shows a cross-sectional view of a rotary head mechanism in a conventional magnetic recording/reproducing apparatus such as an R-DAT or a VTR, in which 2a is a five-part ball bearing, 2b is an upper ball bearing,
10 is the rotor side of the rotary transformer, 11 is the stator side of the rotary transformer, 13 is a shim washer, 14 is a transformer stand, 15 is a shaft, 16 is a relay board, and 16a.

16b is a rieet wire, and 17 is a magnetic head.

As shown in FIG. 2, the conventional rotating head mechanism has a structure in which two ball bearings 2a and 2b are fixed, and in this case, each ball bearing 2a.

Since the position between 2b and 2b is preloaded, there are many performance problems such as no need for preload during assembly, loss of preload due to changes over time, and motor load fluctuations due to changes in f pressure due to ambient temperature. Furthermore, as shown in FIG. 2, since it has a transformer stand 14, a shim washer 13 for adjusting the rotary transformer gap is required to adjust the shim thickness in stages, and a part of the transformer stand 14 is required for attaching the upper tram. After gluing the mounting surface of the transformer,
All that was required was touch and positioning through cutting. Also, when assembling, the magnetic head 17 and the rotary transformer rotor l.
For connection with O, install a relay board 16, etc., draw lead wires 16a and 16b to the top of the upper drum, and solder them.
Workability is not good.

[Problems to be Solved by the Invention] As mentioned above, the conventional rotary head mechanism requires a transformer stand and also has to be provided with a relay board.

Furthermore, the transformer stand requires dimensional accuracy and requires machining after assembly, making it an expensive component. In addition, the rotor or bearing inner ring holder in the motor part was structurally preloaded, so it had many drawbacks such as extremely poor serviceability.

This invention was made in order to solve the conventional problems as described above, and it is possible to create a rotating head mechanism with high assembly accuracy using an in-cylinder configuration that does not require the installation of a transformer stand or a relay board. An object of the present invention is to provide a magnetic recording/reproducing device having the following features.

[Means for Solving the Problems] In order to achieve the above object, the magnetic recording and reproducing device of the present invention has a configuration in which a ball bearing with a shaft and a ball bearing are respectively arranged with respect to the rotating shaft of the rotating head mechanism. It is something that you have.

[Function] By having the above configuration, noise intrusion due to the short cable length between the head and the transformer is reduced, and since a transformer stand is not required, the rotating head assembly is made smaller and lighter, and assembly accuracy is improved. Improvements in performance, etc. became the turning point.

[Example] Fig. 1 is a cross-sectional view of the rotating head a structure in the magnetic recording/reproducing device of the present invention, l is an upper tram, 2 is a ball bearing, 3 is a lower drum, 4 is a coil spring, and 5 is a ball bearing with a shaft. , 6 and 7 are the rotor and stator parts of the motor, and 8
9 is a rotation detecting section, 9 is a head assembly section, 10a is a lead wire, 12 is a spring seat, 18 is an adjustment bolt, and 19 is a set screw. Further, the same reference numerals as in FIG. 2 indicate the same or corresponding parts.

In the embodiment shown in FIG. 1, the upper tram 1 is in contact with the inner ring of the ball bearing 2. Since the outer ring of the ball bearing 2 and the bear link housing of the lower tram 3 are not fixed, the preload from the coil spring 4 or a steady preload that is constantly applied is applied. With this configuration, dimensional differences due to differences in expansion due to differences in the materials of the shaft and housing due to changes in ambient temperature, effects due to changes over time, assembly defects, etc. are minimized. Since the lower part of the ball bearing 5 with a shaft is a direct bearing with a shaft, there is no change in preload even if the rotor 6 of the motor is removed. Also, set screw 19 of upper drum L
The head height can be adjusted in each step by loosening the adjustment bolt 18 without pinching the gap shim between the rotor side lO and stator side 11 of the rotary transformer, and the head height can be adjusted immediately after adjustment. After adjustment, tighten the set screw 19 on the upper drum l and remove the adjustment bolt 18.

Work efficiency is improved by directly connecting the magnetic head 17 on the rotor side 10 of the rotary transformer in advance.

Although FIG. 1 shows an example of the use of the adjusting m-bolt 18, it is also possible to use a male screw instead of the female screw in the shaft-mounted ball bearing 5 and use an adjustment nut. Further, after assembly, it may be used as a screw fastening material and left attached without using it as an adjustment tool.

The same effect may be obtained by using a conventional type ball bearing instead of the shafted ball bearing material 5, fixing the outer ring, and pressing the inner ring against the bushing of the motor rotor 6.

[Effects of the Invention] As explained above, the rotating head mechanism of this invention has the advantage that when conventional ball bearings are used, the head height and transgear love must be readjusted when the motor rotor is removed. However, by using ball bearings with sleeves, there is no need for readjustment, and by using ball bearing links with shafts, the ball revolution is faster than in rotating drum devices using conventional ball bearing links. The smaller diameter reduces shaft loss and improves the accuracy of runout, etc.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a rotary head mechanism in a magnetic recording/reproducing apparatus of the present invention, and FIG. 2 is a sectional view of a conventional rotary head mechanism. In the figure. ■: Upper drum 2: Ball bearing 3: Lower drum 4: Coil spring 5: Ball bearing with shaft 6: Motor rotor section 7 and motor stator section 8 are rotation detection sections 9: Head assembly section 10: Rotor side of rotary transformer 11: Stator side of rotary transformer 10a: Lead wire 12: Yaneza Patent Attorney 1) Haru Kitatake Figure 1 Figure 2

Claims (2)

[Claims] (1) A magnetic recording and reproducing device equipped with a rotary head mechanism having a magnetic head, characterized in that a ball bearing with a shaft and a ball bearing are respectively arranged with respect to the rotating shaft of the rotary head mechanism. . (2) The magnetic recording/reproducing device according to claim (1), wherein the ball bearing is arranged by attaching a preload spring to the outer ring of the ball bearing and the housing.