JPS60260278A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To attain reading of characteristic information by setting a high-speed tape feeding speed by means of a high-speed value so as to overlap partly a signal of each head decided by the characteristic of a reproducing system in a rotary head type device. CONSTITUTION:An object value of a relative speed between a tape and head at high-speed reproduction is set to a relative speed VRO' between the tape and head at normal reproduction. When the high-speed tape feeding speed is set to the maximum value N times the tape feeding speed so that the reproducible range is overlapped party for the signal of each head decided by the characteristic of the reproducing system, the permissible relative speed deviation in the tape line velocity direction is increased and even when the deviation of the tape feeding speed is large, the specific information is read.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a recording and reproducing apparatus, particularly a rotating head type recording and reproducing apparatus, which is suitable for use in reading specific information when feeding a recording medium at high speed. Regarding.

BACKGROUND TECHNOLOGY AND PROBLEMS In conventional rotary head type recording and reproducing devices, reading specific information such as the tape feed amount and tape position during high-speed tape feeding such as fast forwarding and rewinding of a tape as a recording medium is performed using the rotating head. For example, control (
This is done by reading out signals such as CTL) signals and address signals.

However, in the case of such conventional methods, it is necessary to provide a dedicated fixed head in addition to the rotary head, which requires many man-hours for manufacturing, processing, assembly, adrenal glands, etc., and is also expensive. It's inconvenient.

Additionally, there are performance problems such as an inability to obtain output from the fixed head due to tape repelling or stumbling during commercial speed tape feeding.

Furthermore, a fixed head is used to record specific informationζ
Therefore, it is necessary to secure a dedicated recording area in the longitudinal direction of the tape, and there are also disadvantages such as the area where the original information recorded by the rotary head is limited.

OBJECTS OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a recording and reproducing apparatus that can reliably read specific information during high-speed tape feeding without using a dedicated fixed head.

Summary of the Invention In this invention, the target value of the relative speed between the tape and the head during high-speed playback is set to the relative speed between the tape and the head during normal playback, and the signals of each head determined by the characteristics of the playback yarn are set within the playable range. The high-speed tape feed speed is set by the high-speed value of the tape feed speed so that the tape feed speeds partially overlap. As a result, the present invention eliminates the need for a fixed head, resulting in lower costs and a reduction in the number of manufacturing steps. Further, since the fixed head is not required, there is no need to provide a recording area for the fixed head, and the area for recording the original information is substantially expanded, allowing effective use of the tape.

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on FIGS. 1 to 9.

In this invention, when a tape on which certain information is recorded is played back at four speeds without forming a guard pan F using a plurality of rotating magnetic heads having different azimuths (gap angles),
■We are focusing on the fact that the relative speed between the tape and the hent is different between the azimuth and θ azimuth, so the allowable relative speed deviation becomes large.

FIG. 1 shows a tape pattern of a helical scan type recording/reproducing apparatus. In the figure, arrow T indicates the tape transport direction, and arrow H indicates the head scanning direction.

Therefore, the relative speed VRi) between the tape and the head during normal playback (FWD) is as follows...+11 However, in the above equation +11, VDO is the rotational speed of the head during normal playback, and vt is the rotational speed of the head during normal playback. The tape feed speed during normal playback, θ0, is the still angle.

Assuming that a head with an azimuth ±η0° is used, the vertical component (effective relative velocity) VRO with respect to the relative velocity gap during normal reproduction is expressed by the following equation.

V RO= V ROCO3η0 ・・・・・・(2)
Further, the recording angle θR at this time can be determined by the following equation.

Next, in the tape pattern shown in Figure 1, when the operation mode is set to fast forward (FF) or rewind (REW), the trajectory of each head is as shown by arrows F and R, respectively, in Figure 1. becomes. The relative speed vR' between the tape and the head when fast forwarding or rewinding is performed at N times the speed is as follows.

)2 (4) However, in the above equation (4), v□ is the head rotation speed during fast forwarding or rewinding, and N-vt is the tape feeding speed during fast forwarding or rewinding. Note that N is N when fast forwarding.
>0, and N<O during rewinding.

Therefore, the relative speed V between the tape and the head during normal playback is
If the head rotation/speed VD and multiplication rate N during high-speed playback are selected so that RO is equal to the relative speed vR' during fast forwarding or rewinding, that is, during high-speed playback, then the speed will be the same as when forwarding or rewinding. This means that specific information on the tape can be read even during high-speed playback.

However, in reality, the frequency of information read by the head is
Since it is effective in the velocity component perpendicular to the gap direction, the above (4)
Let's take a look at the component perpendicular to the gap in the equation.

Figures 2 and 3 show the relationship between the head trajectory during fast forwarding and rewinding, and the relative speed in the direction perpendicular to the gap, as well as the effective relative speed. Assuming that the angle formed by the longitudinal direction of the tape and the trajectory of the head is 6 angles, the 6 angles are expressed by the following equation.

Therefore, the vertical component velocity VR^ for the gap of the A trunk during fast forwarding is as follows.

VRA=VR' c, os(ηO+(θT-〇R))
(6) Also, the vertical component velocity VRR of the B track with respect to the cap is expressed by the following equation.

VHB=Vj cos t770- (θd-θR))
(7) Similarly, the vertical component velocity VR^ for the A track gap and the vertical component VRB for the B trunk gap are as shown in the following equations.

VR^=VR'CO3 (770' (θR-θT))
...-181Vue=v+j cos(ηo+(θ to θv)) ...(9) Now, when vRo-vj, the deviation between VRO and VRA+'V RB is calculated as follows. Become.

In other words, in the case of A trunk during fast forwarding, RO cos (η0+(θd −〇R))−CO3η0COS
eta0
η0×100(%) (11)

Also, in the case of track A during rewinding, RO cos (ηo-(θR-θT)) −cosη0
COSη0 xlOO(%)...(12), and in the case of track B during rewinding, VRO CO3η0 x100(%)...(13).

A diagram of these relationships is shown in Figure 4. That is, Figure 4A represents the time of fast forwarding, and Figure 4B represents the time of one rewinding.
For that, VRA is delayed by ΔVRI, and WRIT is delayed by ΔVRI.
This means that during rewinding, VRA becomes faster by ΔVR3 and VRR becomes slower by ΔVR4 with respect to VRO. From this, it can be seen that during high-speed playback such as fast forwarding or rewinding, the relative speed between the tape and the head differs due to the difference in azimuth.

Next, we calculate the relative velocity deviation allowed for reading information on the tape during fast forwarding and rewinding by ΔVRO (%o-p
), if we draw a wheel in Figure 4, it will be expressed as in Figure 5. FIG. 5A shows the case when fast forwarding, and FIG. 5B shows the case when rewinding.

Therefore, ΔV RO>ΔVR1, ΔVR2, ΔvR3+
If selected so that ΔVR4, the allowable relative speed deviation is 2Δ
VRO (%) to 2Δvsto+ΔVR1+ΔVR2(
(when fast forwarding) or 2Δvao+ΔVRJ+ΔVR4 (when rewinding). As a result, for example, the permissible relative velocity deviation in the tape linear velocity direction can be increased.

In the case of Fig. 5 mentioned above, the deviation of VRA and VRIl with respect to VRO when vRF = VR' is calculated, but when this is set as VRO-VRA-''VRB, the deviation of VRA and VRIl with respect to vR'o is calculated. If the deviation of VR' (VRA, ■crystal) is calculated in the same way as above, the result can be expressed as shown in Figure 6. In the case where Figure 6A is during fast forwarding and Figure 6B is during rewinding. In addition, in Fig. 6, ΔVR
.

is the relative velocity deviation allowed for reading information on the tape during fast forwarding and rewinding, and ΔVRS is the A during fast forwarding.
Deviation of VRA to VRO at the track, ΔvR
’2 is V for VRO in track B during fast forwarding
The deviation of RGI, ΔVRS, represents the deviation of vTh with respect to VRO in track A during rewinding, and ΔvR3 represents the deviation of VR6 with respect to vR′o in track B during rewinding.

Therefore, ΔVR et al〉ΔVR'i, ΔvR4+ ΔvR'
3 rΔVR'4, the allowable relative speed deviation is 2ΔVRS (%) to 2ΔvR'o+Δvis+Δ
It can be expanded to VR'4 or 2ΔvR'o+ΔVRS+ΔVR'l. As a result, for example, the relative velocity deviation in the tape linear velocity direction can be increased, and the range in which specific information can be read is expanded accordingly.

Incidentally, ΔVRP is determined by the playback system, particularly the open-to-touch range of a PLL (not shown) constituting the electromagnetic conversion system of the playback system. Therefore, if ζ, for example ΔVRO, is fixed in terms of hardware, Δv R's >ΔvR'i + Δv
To satisfy the condition of R'2 + ΔV R'l + ΔVR2, ΔvR't + ΔvR'2 + ΔV R
It is necessary to consider the setting of S r ΔVR'4.

These ΔV R'i + ΔV R'2 + ΔvR'
l, ΔVRS is ΔVR1+ ΔVR2+ ΔVR11+ ΔVR expressed by the above equation (13)
4 should be considered in correspondence with each other. That is, ΔVR1~Δ
VR4 is related to the angle 0 between the longitudinal direction of the tape and the trajectory of the head during high-speed playback, and this angle 0 is also the same as the above (5).
) is expressed by the formula. From this equation (5), 0 is the -rad rotational speed vO and tape feed speed hlvt during high-speed playback.
, and therefore the angle θT, that is, each deviation ΔVRI~ΔV
For R4 (ΔVR; ~ΔvR'4), the highest N times speed value may be determined in advance on the system.

Therefore, in the above-mentioned FIG.
This is a case where the maximum value of N times speed is set so that +ΔV *'l + ΔvR'4. Incidentally, ΔRo=ΔV
R'1 + ΔV R'! +ΔVRS+ ΔvR'
4 and ΔVR3<ΔVR'l, ΔVR'2 + ΔVH
In the case where the maximum speed of N times is set so that the layer ΔvRs is set, the results are as shown in FIGS. 7 and 8, respectively, without taking the case of fast forwarding as an example.

That is, in FIG. 7, ΔvR et al.=ΔvR'! +ΔV
Since R'2, the relative speed VR3 during nokomaru playback
Relative speed VRAI v crystal deviation Δ during high-speed playback
V most.

ΔvR'2 exactly coincides with the relative speed deviation ΔvR'o that is allowed because specific information on the tape continues during high-speed reproduction, and although there is not enough margin, specific information can be read from the tape.

On the other hand, in Fig. 8, ΔVR et al.〈ΔVR'1 + ΔvR
'2, so ΔVR'i, ΔVR'! Is the allowable relative speed deviation ΔVR? ), resulting in a situation in which some specific information, as shown by diagonal lines in the figure, cannot be read. 1 Yes, ζ, in this invention, Δvia and Δvui ~ ΔVR'1
The relationship between ΔVR et〉Δvhi, ΔvRS + Δv
The PLL lock range of the electromagnetic conversion system, the maximum value of N times speed, etc. are set so that RS + ΔvR, and the specific information can be reliably read during high-speed playback.

FIG. 9 shows an embodiment of the present invention, in which the input terminal (
]1) The analog signal from 1) is low-pass filtered (12)
The signal is supplied to the analog-to-digital converter (13) through the analog signal, where it is converted into a digital signal, and then supplied to the recording signal generation circuit (15) via the contact a side of the switch circuit (14). In addition, by switching the switch circuit (14) to a contact point, the terminal (16
It is also possible to directly supply the digital signal from the ) side to the recording signal generation circuit (15).

The recording signal generating circuit (15) performs signal processing such as adding an error correction code to the data, interleaving or modulating the data based on the timing signal from the timing generating circuit (17), and then sends the signal to the switch circuit (18). supply to. The switch circuit (18) is connected to the rotating head (21^) (
This is for switching the head (21B) by the switching signal from the timing generation circuit (17).
The head (218) is alternately switched between a half-rotation period including the tape contact period and a half-rotation period including the tape contact period of the head (21B). This timing generation circuit (17
) is a rotary head (21A) from the pulse generator (not shown).
).

A pulse 3011z indicating the rotational phase of the rotary heads (21A) and (21B) obtained in synchronization with the rotation of the rotary drive motor i' (21B) is supplied. The signal from the switch circuit (18) switched by the switching signal from the timing generation circuit (17) is sent to the amplifier (
19^) and (19B), and then supplied to the rotating heads (21A) and (21B') via the contact R side of the switch circuits (20A) and (20B), respectively.
Magnetic tape (
24). Switch circuit (20^) and (2
0B) is connected to the R side during recording, and is switched to the P side during playback.

In addition, (25^) and (25B) are the playback switch circuits, (
20^), , (20B) is an amplifier to which the playback output from the corresponding rotary head (21A), (21B) is supplied when switched to the contact P side, and these amplifiers (2
Each output of (5A) and (25B) is connected to a switch circuit (26
). The switch circuit (26) uses a 30Hz switching signal from the timing generation circuit (17) to control the half-rotation period including the tape contact period of the head (21^) and the tape contact period of the head (21B) in the same way as during recording. It is switched alternately with a half-rotation period including.

The output signal switched by this switch circuit (26) is then transferred to an electromagnetic conversion circuit (27) including an equalizer and PLL.
). The lock range of the PLL of this electromagnetic conversion circuit (27) is set in consideration of the above-mentioned ΔVuo. The output signal from this electromagnetic conversion circuit (27) is supplied to an error correction circuit (28), where error correction is performed as necessary. The signal is further supplied to a digital-to-analog converter (29), where the digital signal is converted into an analog signal, and then the low-pass filter (3
0) and is output as an ordinary analog signal to the ζ output terminal (31). Furthermore, if it is desired to directly extract digital data, the digital data can be derived from the output terminal (32) of the error correction circuit (28).

Also, (33) and (34) are reels (22) and (2
3) A rotation detector for detecting the rotation period,
The outputs of these rotation detectors (33) and (34) are supplied to a reel servo circuit (35).The reel servo circuit (35) is supplied with the output of each rotation detector (33j, <34), for example. A pair of amplifiers (35a) and (35b)
, a period/voltage conversion circuit (35c) that converts the period information from the amplifier (35a □), (35b) into voltage, and (35d), a conversion circuit (35c), (35d).
A squaring circuit (35e) and (35f
) and square circuit (35e).

It consists of an adder (35g) that adds the respective outputs of the adders (35f), and a differential amplifier (35h) to which the output of the adder (35g) is input to one end. This differential amplifier (35
'')''Other 0 people ``end''・Reference voltage ('',!:,Mt''7
Grounded on the g-s side. The output of the differential amplifier (35h) is then passed through the switch circuits (3B) and (39) to the motors (40) and (40) of the ζ reels (22) and (23) respectively.
41), these motors (40), (41
), the reels (22) and (23) are rotationally driven. Note that the switch circuits (3B) and (39) are reels (22).

If (23) are the supply side and the winding side, respectively, they are connected to the contact a side during fast forwarding, and are switched by the microcomputer (36) as a system controller. The contact a side of the switch circuit II (3B) and the contact side of the switch circuit (39) are connected to the back tension generation circuit 1.
2&(42).

Therefore, during fast forwarding, the output of the reel servo circuit (35) passes through the contact a side of the switch circuit (39), and servo is applied to the motor (41) of the take-up reel (23), and at the same time, the back tension generation circuit (42) The output from the tape (24) is supplied to the motor (40) of the supply reel (22) through the contact a side of the switch circuit (38).
The back tension is increased and it is lifted. Then, when rewinding, the operation is exactly the opposite of fast forwarding.

Further, subcode information as specific information is supplied to the microcomputer (36) from a subcode extraction circuit (43) provided on the output side of the error correction circuit (28). So-called cueing of program numbers, time codes, etc. is performed.

Note that the microcomputer (36) as a system controller controls the device so that it can reproduce at least an arbitrary N times speed, and the maximum value of N times speed at that time is ΔV RFI >ΔvR'1 + ΔVR'2 as described above. ．．
It is set to satisfy the relationship ΔvRS + ΔVR′l. Further, during normal playback, the tape is driven by a capstan.

Effects of the Invention As described above, according to the present invention, ΔvR′o〉ΔvR′1 +ΔVR;
P of the electromagnetic conversion system so that + ΔVRS, ΔVR'l
Since the lock range of LL and the maximum value of N times speed are set, it is possible to easily read out specific information even when the deviation of the tape feed speed is large, and it is also possible to manage relative speeds, especially tape Linear speed control can be made looser.

Furthermore, since specific information can be read out using only the rotating magnetic head without using a dedicated fixed head as in the past, production man-hours and costs can be reduced. Also, since the recording area of a fixed head is no longer required,
There is also the benefit of being able to use the tape more effectively.

[Brief explanation of the drawing]

1 to 8 are diagrams for explaining the present invention,
FIG. 9 is a block diagram showing one embodiment of the present invention. (22) and (23) are reels, (27) are electromagnetic conversion circuits, (33) and (34) are rotation detectors, (35) are reel servo circuits, (36) are microcomputers, (
40) and (41) are motors, and (43) is a sub-code extraction circuit. Figure 1 Figure 8 Procedural amendment document January 17, 1985 Manabu Shiga, Director General of the Patent Office 1. Indication of the case 1988 Patent Application No. 11.6115 3. Person making the amendment Related Patent Applicant Address 6-7-35, Kitashinyo, Tokyo Parts Store Name (
218) Sony Corporation Representative Director Noriyoshi Ohga 4, Agent 7, Correction 0 subject 舅过 θ@pi, (5B'Il[I
f, K H parting (rA on page 7, line 3 of 11 specifications)
Add "When rewinding" before "Rack". (2) Formula 01 on page 7 of the same is corrected as follows. (3) Formula (11) on pages 7 and 8 of the same document is corrected as follows. X100 l (%) ...(11) N (4) Same, correct formula (12) on page 8 as follows. ...(12) ...(13) (6) Add "Effective." before "Relative speed" on page 9, line 8. (7) Add the following between lines 8 and 9 on page 9. "Figure 4 shows the speed during normal playback. This shows the relationship between the relative speed of the tape and the head and the effective relative speed of the A head and B head during fast forwarding and rewinding when the relative speeds of the tape and head during fast forwarding and @rewinding are equal. vice versa,
When the effective relative speed during normal playback and the effective relative speed of heads A and B during fast forwarding and rewinding are equal, the relative speed during normal playback and the relative speed of heads and B heads during fast forwarding and rewinding are equal. The relationship is shown in FIG. Figure 5A
5B is the one when fast forwarding, and FIG. 5B is the one when rewinding. Here, if we add the deviation between vR6 and vRA+v-, we get the following. For A track during fast forwarding, Δ...(14) For B track during fast forwarding,...(15) For A trunk during rewinding,...(16) When rewinding In the case of track B, in order to make the relative speed during forwarding equal to the relative speed during normal playback, the relative speed during fast forwarding needs to be slower than the relative speed during normal playback by ΔvRa. In addition, in order to make the effective relative speed of the A head during rewinding equal to the effective relative speed during normal playback, the relative speed during rewinding must be increased by ΔVR3 from the relative gain during normal playback.
When rewinding, it is necessary to slow down f3-. Tsudo)
In order to make the effective relative speed of the same as the effective relative speed during normal playback, it is necessary to make the relative speed during rewinding faster than the relative speed during normal playback by ΔVR i. Correct [ΔVROJ on page 10 line to [ΔVR5J]. (9) Same, same page, line 11, "Figure 4" is corrected to "Figure 5." C11 Same page, correct "Figure 5" in lines 12 (2 places) and 13 to "Figure 6." (11) Ibid., page 9, line 14 to page 1O, line 7, “Therefore,
...This is a case. ” to be deleted. (12) In the same page, page 1e, lines 19-20, "grounded to the ground side as a reference potential" is corrected to "connected to the reference power source V ref". (13) In the drawings, Figures 4, 5, 6, and 9 will be corrected as shown in the attached sheet. Figure 4 A Figure B A

Claims (1)

[Claims] The target value for the relative speed of the tape and head during same-speed playback is set to the relative speed of the tape and head during normal playback, so that the playable range of signals from each head determined by the characteristics of the playback system partially overlaps. A recording/reproducing device characterized in that a high-speed tape feed speed is set by a high-speed value of the tape feed speed.