JPS61202321A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To perform the recording/reproducing jobs with no omission of signals by increasing the projecting degree of upper one of two rotary magnetic heads provided with different height from the circumferential surface of its rotary drum compared with the projecting degree of the other lower magnetic head. CONSTITUTION:The rotary magnetic heads C1 and C2 for color signals are attached at the same height position H1 over an axis Z of a tape guide drum 10. While the rotary magnetic heads Y1 and Y2 for luminance signals are attached at a position H2 lower than the H1. Both heads C1 and Y1 are set at the same position over the revolving direction of a rotary drum 14. While heads C2 and Y2 are set opposite to the heads C1 and Y1 in the diameter direction of the drum 14. Furthermore the projecting degrees of upper heads C1 and C2 are increased compared with those of lower heads Y1 and Y2. Thus these heads can all have good contacts with a magnetic tape 15 for scanning.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic recording/reproducing device, and in particular to a magnetic recording/reproducing device that records different types of information signals in separate areas in the width direction of a magnetic tape using separate rotating magnetic heads. The present invention relates to a magnetic recording and reproducing device for reproducing.

2. Prior Art At present, the Helical Gyan magnetic recording and reproducing apparatus (VTR), which uses 1/2 inch wide magnetic tape, has a relatively narrow recording/reproducing band for home use, so it is separated from the color video signal. Of the luminance signal and the carrier color signal, the luminance signal is frequency-modulated to become a frequency-modulated wave, and the carrier color signal is a low-pass converted carrier color signal. After IC, the frequency-modulated luminance signal is frequency-division multiplexed, and this frequency-modulated wave is The system employs a so-called low-frequency conversion color recording and reproducing method that records multiplexed signals on magnetic tape and reproduces them.Also, in order to improve tape usage efficiency, the azimuth angle of each rotating head that records adjacent tracks is adjusted. A different guard panless recording method is used. On the other hand, commercial VTRs intended for broadcasting, especially VTRs with built-in cameras, have the same tape width as home VTRs in order to make the device smaller and lighter and to improve the quality of reproduced color video signals. on magnetic tape,
A method is adopted in which the luminance signal and the color signal are recorded on separate tracks using separate rotary heads, and a guard band is provided between adjacent tracks for recording and reproduction.

Problems to be Solved by the Invention However, the above-mentioned conventional color video signal recording and reproducing apparatus has the following problems:
Since both have a guard band, the efficiency of magnetic tape usage is poor, and if the rotating head crosses the guard band and scans adjacent tracks during playback, two adjacent tracks will have an FM Since the luminance signal and the FM color difference signal are recorded separately, the FM color difference signal (or FM luminance signal) must be reproduced with a rotating magnetic head for the luminance signal (or a rotating head for the color difference signal), and the field correlation It is not possible to use a crosstalk cancellation method using , which has the problem of resulting in a reproduced image with noticeable crosstalk.

Therefore, the present applicant previously proposed patent applications (2) and (3) (invention title: "Color video signal recording and reproducing device") filed on February 25, 1985. According to the color video signal recording and reproducing apparatus proposed by the present applicant, luminance signals and color signals are separated in the tape width direction by a track pattern as shown in FIG. 9, respectively, in recording areas W-1 and W. -2
and play it back. In the figure, FM luminance signals are recorded in predetermined width regions W-+ on the upper and lower sides in the tape width direction of a magnetic tape 1 having a width of 1/2 inch, for example, by first and second luminance signal rotating magnetic heads. First track TYI
~TYIO is formed sequentially at an angle θ with respect to the longitudinal direction of the tape without a guard band. Accordingly, second tracks Tc+ to Tc+a on which FM color difference signals are recorded are sequentially formed with no guard band and are inclined at an angle θ with respect to the longitudinal direction of the tape.

In addition, in FIG. 9, tracks 2+, 22, 3, and 4 recorded along the longitudinal direction of the magnetic tape 1 are tracks recorded and formed by a dedicated fixed head.
+, 22 is the first. 3 is an audio track where the audio signal of the second channel is recorded, 3 is a time code track where a time code for knowing the position information on the tape is recorded, and 4 is a control track where a control pulse of a fixed period is recorded. .

Further, the present inventor has proposed that in a tape guide drum 7 having a configuration consisting of a lower fixed drum 5 and an upper rotating drum 6 as shown in FIG. As a result of an experiment on the formation status of the air film formed between the rotary drum 6 and the rotary drum 6, it was confirmed that the air film is thicker at the upper part of the rotating drum 6 and thinner at the lower part (t+>Lz), as shown in 9.

In view of the above experimental results, it is an object of the present invention to provide a magnetic recording/reproducing apparatus which can be particularly suitably applied to, for example, the color video signal recording/reproducing apparatus proposed by the present applicant.

Means for Solving the Problems The present invention aims to reduce the amount of protrusion of the rotating magnetic heads, which are provided at different heights on the rotating drum above the fixed drum, from the circumferential surface of the rotating drum. is determined to be larger than the amount of protrusion of the rotating magnetic head below.

Effect: By determining the distance between the protrusions in this manner, the head touch of the rotating magnetic head disposed above with respect to the magnetic tape is improved.

Embodiment Next, an embodiment of the magnetic recording/reproducing apparatus according to the present invention will be described.

FIG. 1 shows an enlarged view of the main part of the present invention, FIGS. ) and FIG. 4 are enlarged views showing how the rotating magnetic head is attached to the rotating drum of the tape guide drum 10, respectively.

As shown in FIGS. 2A and 2B, the tape guide drum 10 includes a lower fixed drum 11 and a lower fixed drum 1.
1, and an upper rotating drum 14 which is fixed to a motor shaft 13 of the drum motor 12 and rotates in six directions indicated by arrows.

C+ and C2 are for 1. This is a second rotary magnetic head for color signals, and is mounted at the same height position indicated by H1 above the axis Z direction of the tape guide drum 10.

YI and Y2 are 1. This is a second rotary magnetic head for brightness signals, and is mounted at a position indicated by H2, which is lower than the above-mentioned height position H1. In addition, rotating magnetic heads C+, Y
I is arranged at the same position in the rotational direction of the rotating drum 14, and the rotating magnetic heads C2 and Y2 are arranged opposite to the rotating magnetic heads C+ and YI in the radial direction of the rotating drum 14.

The magnetic tape 15 is wound spirally around the tape guide drum 10 over an angular range of just over 180 degrees determined by guide poles 16 and 17, and is guided by a lead 18 at its lower edge in the direction of arrow B. Run. Rotating magnetic head C
+, C2, YI, Y2 scan the magnetic tape 15,
A track pattern as shown in FIG. 9 is formed on the magnetic tape 15. As shown in FIG.

The above-mentioned rotating magnetic heads C+, C2, Y], and Y2 are mounted as described below so that their positions can be adjusted individually, and moreover, the positions can be adjusted from above the rotating drum 14. .

In Figures 1 to 4, 20 indicates four parts, and the rotating drum 1
It is formed near the outer periphery of the lower surface of 4.

These four parts 20 are especially for mounting the rotating magnetic head C1, and this ceiling surface provides a mounting surface 21 for the rotating magnetic head C1. In addition, the lower surface 2 of the rotating drum 14
2, a portion around the recess 20 is used as a mounting surface 23 for the rotary magnetic head YI. A rectangular window 24 is formed on the circumferential surface of the rotating drum 14 so as to communicate with the recess 20. 25 is a notch, and the rotary drum 1
It is formed on the lower surface of 4.

As shown in FIGS. 5(A) and 5(B), the rotating magnetic head C1 is fixed on a small support 26 having a width W and a length. The small size support 26 to which the rotating magnetic head C1 is fixed in this manner is shown in FIGS. 3(A) and 3(B).
And as shown in FIG. 4, the left and right mounting holes 26a, 26b
the screw 27a.

27b and is attached to the mounting surface 21 of the recess 20, and the head surface side of the rotating magnetic head C1 protrudes from the window 24.

The rotating magnetic head Y1, as shown in FIGS. 1 and 4,
It is fixed to a small size support 28 having the same shape as the above small size support 26, and as shown in FIG. It is screwed onto a large-sized support 29 that is one size larger with screws 30a and 30b. This large size support 29 is attached to the mounting surface 23 through left and right mounting holes 29a, 29b with screws 31a, 31b, and the head surface side of the rotating magnetic head Y1 protrudes from the notch 25.

The support 28 and the support 29 may be integrated.

With the rotating magnetic heads C+ and YI aligned and attached in the axial and Z directions, the small size support 26 and the large size support 29 are in a positional relationship as shown in FIG. 3 (A>) in a plan view. That is, the left and right side edges 29c and 29d and the rear edges 2 and 9C of the large size support 29 are the left and right side edges 26c and 26d and the rear edge 26 of the small size support 26, respectively.
It is located outside of e. Since the small size support 26 and the large size support 29 are in such a positional relationship, adjustment holes are formed from the top side of the rotating drum 14 corresponding to each support 26 and 29, as will be described later. .

In particular, as shown in FIGS. 3(A), (B) and 4, 3
2.33.34 is an adjustment hole for the rotary magnetic head C1 with a diameter of dl, 35.36.37 is a rotary magnetic head Y with a diameter of dl.
Both adjustment holes are formed in the rotary drum 14 parallel to the axis Z with openings on the upper surface side of the rotary drum 14.

In particular, the adjustment holes 32, 33, and 34 are formed at positions facing the sides R26C, 26d and the rear edge 260 of the small size support 26, respectively. The adjustment holes 35, 36, and 37 are located at the side edges 29C and 29d of the large size support 29, respectively.

It is formed at a location facing the rear edge 29e.

The position of the rotary magnetic head C+ is adjusted using an adjustment bin 38 shown in FIG. The adjustment bin 38 includes a disc-shaped knob 38a, a cylindrical portion 38b having a diameter of dl, and a protrusion 38C eccentric from the cylindrical portion 38b. By inserting the adjustment bottle 38 into the adjustment hole 32 or 33 as shown by the dotted chain line in FIG. 2(B) and rotating it appropriately,
The eccentric protrusion 38c pushes the side edge 26c or 26d, and the small size support 26, that is, the rotating magnetic head C1, is displaced in the circumferential direction of the rotating drum 14, and one of the rotating magnetic heads C1 is displaced.
The 80 degree relative position is adjusted. When the adjustment bin 38 is inserted into the center adjustment hole 34 and rotated, the eccentric protrusion 38G pushes the rear edge 26e, and the small size support 26, that is, the rotating magnetic head C1 protrudes from the circumferential surface of the rotating drum 14. The amount of protrusion of the rotary magnetic head C1 is adjusted.

The position of the rotary magnetic head Y1 is adjusted using an adjustment bin 39 shown in FIG. The adjustment bottle 39 includes a disc-shaped knob portion 39a, a cylindrical portion 39b having a diameter of d2, and a protrusion 39C eccentric from the cylindrical portion 39b. By inserting the adjustment bottle 39 into the adjustment hole 35 or 36 as shown by the dotted chain line in FIG. 3(B) and rotating it as appropriate,
The eccentric protrusion 39c pushes the side edge 29c or 29d, and the large size support 29, that is, the rotating magnetic head Y+, is displaced in the circumferential direction of the rotating drum 14, and one of the rotating magnetic heads Y1 is displaced.
The 80 degree relative position is adjusted. Also, when the adjustment bottle 39 is inserted into the center adjustment hole 37 and rotated, the eccentric protrusion 39
c pushes the trailing edge 29e, the large size support 29, ie, the rotating magnetic head Y+, is displaced in a direction that projects from the circumferential surface of the rotating drum 14, and the amount of protrusion of the rotating magnetic head Y1 is adjusted.

In this case, the amount of protrusion of the rotating magnetic heads C+ and Y+ is the first
Considering the formation of the air film shown in Fig. 0, that is, the floating state of the magnetic tape from the circumferential surface of the rotating drum, the protrusion amount 2I of the upper rotating magnetic head C+ is set to 4 as shown in Fig. 1.
0 um, and the protrusion amount fl 2 of the lower rotating magnetic head Y1 is determined to be 30 μl.

That is, the protrusion amount 21 is 10 μl larger than the protrusion amount e2, and + > I! , 2.

As shown in FIG. 1 (A>), the rotating magnetic heads C2 and Y2 are mounted in the same manner as the above-mentioned rotating magnetic heads C+ and Y+, and their positions are adjusted in the same manner as above. are given the same reference numerals with the suffix A, and their explanations will be omitted.

Further, the above position adjustment is performed with the rotating drum 14 attached to a jig.

Note that when the protruding amounts of the rotating magnetic heads CI, C2, Y+, and Y2 are set to be equal, a particularly thick air film layer is formed when the rotating magnetic heads C+ and C2 located on the upper side contact the magnetic tape 15. The problem occurred at the inlet side of the tape guide drum 10 in the tape running direction, and in some cases the signal to be reproduced was missing.
By determining the protrusion amount as described above, not only the lower rotating magnetic heads Y+ and Y2 but also the upper rotating magnetic heads C+ and C2 are brought into good contact with the magnetic tape 15 and scanned. Therefore, each rotating magnetic head C+, C2.

Head contact with the magnetic tape 15 of Y+ and Y2 becomes good, and not only the luminance signal but also the luminance signal, which tends to cause signal loss, can be reproduced satisfactorily without causing signal loss.

Note that the present invention is not limited to the above embodiments, but
Second, regarding the arrangement of the rotating magnetic heads, the upper and lower rotating magnetic heads may be arranged at different angles in the circumferential direction of the rotating drum.Secondly, regarding the number of rotating magnetic heads, there are three rotating magnetic heads. Thirdly, regarding the structure of the rotary magnetic head, a plurality of rotary magnetic heads may be mounted on a negative support.

Note that the tape guide drum 10 described above is not limited to the color video signal recording and reproducing apparatus described above;
It is also possible to apply this method to the helical scan type magnetic recording/reproducing device disclosed in No. 170012, in which the upper rotary magnetic head records and reproduces video signals and the lower rotary magnetic head records and reproduces audio signals. It is.

Effects of the Invention As described above, according to the magnetic recording and reproducing apparatus of the present invention,
Since the configuration is such that the amount of protrusion of the rotating magnetic heads in the upper set is set to be larger than the amount of protrusion of the rotating magnetic heads in the lower set, the contact of the heads against the magnetic tape is poor due to the influence of the air film. It is also possible to improve the head contact with the magnetic tape for the rotating magnetic head, which tends to move upward, and it is possible to improve the head contact with the magnetic tape. It has the feature that it can be carried out well without causing any deficiency.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view taken along line 1-1 in FIG. 3(B), showing an enlarged view of the main part of a tape guide drum, which is a main part of an embodiment of the magnetic recording/reproducing apparatus according to the present invention. , Figure 2 (A)
, (B) are respectively a plan view and a partially cutaway front view of the tape guide drum, and FIGS. 3 (A>, (B) are respectively FIGS. 2 (A>,
(B) An enlarged plan view and front view showing the mounting portion of the rotating magnetic head on the medium rotating drum. Figure 4 is an elevational view showing the mounting state of the rotating magnetic head. Figure 5 (A) shows the rotating magnetic head installed. A plan view of the fixed small size support, FIG. 5(B) is a cross-sectional view taken along the line VB-VB in FIG. 8 is a perspective view showing the separate adjustment bins, FIG. 9 is a view showing the track pattern formed on the magnetic tape by the apparatus previously proposed by the applicant, and FIG. 10 is a perspective view showing the upper rotating drum and the lower rotating drum. FIG. 3 is a diagram showing how an air film is formed around a rotating drum of a tape guide drum consisting of a fixed drum. 9... Air film, 10... Tape guide drum, 11... Fixed drum, 12... Drum motor, 1
3...Motor shaft, 14...Rotating drum, 15...
Magnetic tape, 16.17...Guide ball, 18...
・Lead, 20... recess, 21... mounting surface, 22.
...Bottom surface, 23...Mounting surface, 24...Window, 25...
・Notch, 26.28...Small size support, 29...
・Large size support, 32-37...adjustment hole, 38.
39...adjustment bin, C+. C2...Rotating magnetic head for color signals, Y! , Y2...
- Rotating magnetic head for brightness signal, 21.22... protrusion amount. Patent applicant: Victor Japan Co., Ltd. Figure 4 Figure 5 Figure 6 Figure 8

Claims (1)

[Claims] a tape guide drum consisting of an upper rotating rotary drum and a lower stationary drum, which guides the magnetic tape so that it travels along the periphery thereof over a predetermined angular range;
A pair of rotating magnetic heads are arranged on the rotating drum to face each other in the diametrical direction, and a plurality of sets of rotating magnetic heads are provided at different heights, each set having a different type of rotating magnetic head. A magnetic recording and reproducing apparatus that records different information signals in areas separated in the width direction of the magnetic tape and reproduces the same, wherein the amount of protrusion of each set of rotating magnetic heads from the circumferential surface of the rotating drum is A magnetic recording/reproducing device characterized in that the amount of protrusion of the rotating magnetic heads in the set arranged above is determined to be larger than the amount of protrusion of the rotating magnetic heads in the set arranged below.