JPH04163710A - Rotary head-drum apparatus commonly used for dat and vtr - Google Patents

Abstract

PURPOSE:To make it possible to perform the recording and the regeneration of both tapes of a VTR and a DAT by providing a VTR head and a DAT head for a rotary drum which is set at a rotary speed that can be commonly used for the digital audio tape recorder (DAT) and the video tape recorder (VTR). CONSTITUTION:The regeneration of an 8-mm VTR has a priority. A DAT head is added to the rotary head drum of the 8-mm VTR, and corresponding signal processing is performed. In the arrangement of the heads in the drum DR, the heads A and C indicated by black circles have the azimuth of +10 deg. (c) of the 8-mm VTR. The heads B and D indicated by white circles have the azimuth of -10 deg. (c). When the drum DR is used for the DAT, the rotating speed of the drum DR is 2,000 r.p.m. in comparison with 1,800 r.p.m. for the 8-mm VTR. The winding angle of a tape T for the drum of 26.67 mmphi is 101.25 deg.. In this way, both DAT and VTR can be used with one apparatus, and the compact configuration and the low cost of the apparatus can be achieved.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention is applicable to DAT (Digital Audio Recorder) and VTR (Video Tape Recorder), for example, 8W
The present invention relates to a rotary head drum device that can be used in common with a tn VTR.

[Prior Art] Both the 8tm VTR and the DAT replay signals recorded on magnetic tape, but since their tape formats are different, conventionally two independent reproducing devices have been used.

[Problems to be Solved by the Invention] However, such a conventional system has the disadvantage that not only the capacity of the device increases, but also the cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary head drum device that enables recording and reproduction of both VTR and DAT tapes.

[Means for Solving the Problem] In order to achieve the above object, a DAT shared VT according to the present invention is provided.
The rotary head drum device R includes a rotary drum whose diameter is set so that it can be used commonly by a DAT and a VTR, and whose rotational speed is set so that it can be used commonly by the DAT and VTR; A plurality of VTR heads are arranged corresponding to the tape winding angle and are set at an angle set corresponding to the azimuth angle of the VTR, and a tape winding angle is set to the rotating drum, and the tape winding angle is set to correspond to the DAT; a DAT head provided at an angle set corresponding to an azimuth angle opposite to the VTR head, and the VTR head and the DAT head,
The present invention is characterized in that the DAT is recorded and reproduced and the DAT and VTR are shared.

[Operation] The VTR head is used for recording and reproducing a VTR tape, and one of the DAT head and VTR head is used for recording and reproducing a DAT tape.

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

Figure 1 shows the DAT tape format and 8mm VTR.
The tape format is underlined.

If the main mechanism is an 8 rtm VTR, and four head drums with a diameter of 26.67+++ mφ are used (the heads are alternately set at an azimuth angle of ±10°), from Fig. 1 ( It is clear that i) the tape wrapping angles are different and (ii) the azimuth angle of the 8m VTR and the azimuth angle of the DAT do not match.

Therefore, as an embodiment of the present invention, for example, 8rInV
It is assumed that a DAT head is added to the rotary head drum of an 8 m VTR, giving priority to TR reproduction, and corresponding signal processing is performed. Therefore, the azimuth angle of the head is also set for 5ilIIIvTR.

Figure 2 (a) shows the arrangement of heads on a drum DR with a diameter of 26.67 mmφ, assuming that heads A and C marked with black circles are +10'' azimuth of 8 tm VTR, and heads B and D marked with white circles The azimuth is 11 degrees.

FIG. 2(b) shows a case where the drum DR shown in FIG. 2(a) is used as a DAT, and the rotational speed of the drum DR in this case is 2000 rpm, whereas it is 1800 rpm in the above-mentioned 8 m VTR. As shown in (i) above, the winding angle of the tape T is 101.25'' for a drum of 26.67111φ.

Figure 3 shows the correspondence between the DAT recording pattern and the head that scans it.
When playing the center of track #1 with an azimuth of 10'', head D scans exactly halfway between tracks #1 and #2, and the azimuth matches the pattern of that track only for 1/2 of the head. Head C scans the center of track #2, but its azimuth angle is opposite to the azimuth of the pattern of that track.
Therefore, no output can be obtained. Further, head B scans the middle between tracks #2 and #3, but like head D, the azimuth of head B matches only 1/2 of the area of the track pattern.

FIG. 4 shows an embodiment of a rotary head drum according to the present invention. For example, in a rotary head drum DR of an 8 mm VTR, a head E having a reverse azimuth angle opposite to that of head A is provided at a position of 101.25 degrees from head A. . With this configuration, if head A scans with an azimuth that matches the pattern of track #1, head E will scan the center of track #2 with the azimuth of the pattern of that track, as seen in Figure 3. It will be scanned for a match. Therefore, in the head drum of this embodiment, heads A and E are used in the DAT mode.

FIG. 5 shows the timing of the reproduction head output by the head drum of the above embodiment, and the state of signal expansion due to writing to the memory (a) and reading from the memory (b).

A1 in FIG. 5(a) is a read output signal from track #1 of head A, and its timing is t, to t, =0.
4375 ms, it is immediately written to the memory l in FIG. 6 at the clock frequency fc, and read from the memory at the clock frequency fc/ from time ℃,' to t1'.
Set the timing to 5m5. Here, =16/9. In addition, although the output timings of heads D, C, and B are also shown in FIG. 5(a), these are not used, and the output of head E whose azimuth matches is performed, and the above memory is output at the timing of ~t1'. write to.

Here, the wrapping angle from head E shown in FIG. 4 is 101.25" from head D, so it is not 1 but 1.
．． A reproduced signal is obtained from 1, + by 8.43
After writing the time of 75m5, immediately f c / k
Read at the clock frequency of ℃1'~t,' = 15
It is assumed that the expanded signal EI' has a timing of ms. After that, the output of head A is written again and then read.

The memory into which the output of the head E is written is the memory 2 in FIG. 6, and the outputs of the memory 2 and the memory I corresponding to the head A are switched and read out every 15 ms by the electronic switch 3, resulting in continuous output. It is said that

Note that in FIG. 5, the timing at which the reproduction of the signal E1 ends is set to 1', but this is the case where reading from the memory 2 is performed immediately after the writing is completed;
Playback end timing: ~t, +s, 4375m5
It is. That is, in FIG. 5(b), the readout signal A of the signal A1
1' can be obtained until t1' at the end of reading becomes t, so if ' is delayed by τ, reading of E and I will also be delayed by τ from the end of writing of El.

The above has explained the expansion of the reproduced signal during reproduction in DAT mode, but if memories 1 and 2 in Fig. 6 are used in reverse, writing at the clock frequency fc/ and reading at the clock frequency fc, a 15ms digital The converted audio signal is 8.43
It will be shortened to 75m5. Furthermore, if the timing is reversed to that shown in FIG. 5, heads A and E can be used to perform DAT recording. However, the azimuth angle of each head is 8
mm VTR is ±100.

FIG. 7 is a timing chart during recording in DAT mode. In the same figure, A, E, A.

t of the digital audio signal, ~1. ．． 1. The time between .
Compress to 5ms recording time. Note that A, is A,′
By reading with a delay of 0.9375 m5 between and t, I ~ t, 1, the recording time of E, + is kept exactly 15 m5, and the recording time is A I
' l El' l A1' ... and 8.4 intermittently
The length is 375m5.

The embodiments of the present invention described above are summarized as follows.

(i) 2'6.67++oφ (7) 4 heads 8 as
VTR (7) Tape winding angle from reference head A to use rotating head drum for DAT playback 10
A fifth head E having an azimuth angle opposite to that of the reference head A is provided at a position of 1.25''.

(ii) Only the reference head A and the fifth head E are used during DAT playback, and each head output (8,4375ms
) is written to memory at clock frequency fc,
The playback time is read from the memory at the clock frequency fc/ and is set to 15 ms.

(fit) Recording in the DAT mode is performed by scanning in the opposite direction to (ii) by shortening the time length of each signal of 15 ms to 8.4375 m5.

[Effects of the Invention] As explained above, according to the present invention, playback and recording in DAT mode can be performed by simply adding one auxiliary head to the rotating head drum of a VTR, and a single device can perform playback and recording. It becomes possible to use both a DAT and a VTR, which has a significant effect in reducing the size and cost of the device.

[Brief explanation of drawings]

Figure 1 shows 8 mm VT in DAT tape format.
Figure 2 shows the arrangement of 8mm VTR and DAT heads for a 26° 67 mm drum. Figure 3 shows the correspondence between the DAT recording pattern and the head that scans it. 4 is a diagram showing an embodiment of the present invention, FIG. 5 is a timing chart for explaining the playback head output and signal expansion by the memory according to the embodiment, and FIG. 6 is a diagram showing the memory according to the above embodiment. FIG. 7, which is an explanatory diagram of the signal processing used, is a timing chart during recording in the DAT mode according to the embodiment. DR・・・・・・26.67mmφ8 rrm
VTR drum, A~D...8m
mVTR drum head, E・・・・・・DAT
Additional head for 1.2... Memo 1
3......Electronic switch.

Claims (1)

[Scope of Claims] A rotating drum whose diameter is set to allow the use of a DAT and a VTR, and a rotational speed that allows the use of the DAT and the VTR; A plurality of VTR heads are arranged corresponding to the tape wrapping angle and are provided at an angle set corresponding to the azimuth angle of the VTR; a DAT head provided at an angle set corresponding to an azimuth angle opposite to that of the VTR head; the VTR head and the DAT head record and reproduce the DAT, and the DAT and VTR
A rotary head drum device for a DAT shared VTR, characterized in that it is used in common with a DAT shared VTR.