JPS6098552A - Variable speed control device of vtr - Google Patents

Abstract

PURPOSE:To obtain a variable speed control device for a VTR which can execute fine intermittent driving feeding every frame similarly to a case using a CTL signal and also can execute noiseless intermittent driving slow motion reproducing similar to a CTL method by using an error signal obtained from a reproduced pilot signal. CONSTITUTION:When a pilot signal extracted from a signal circuit 6 is supplied to a mixer 9 through a BPF8 under the status that local frequency outputted from a local frequency generator 10 is supplied to the mixer 9 as frequency f2, a signal component corresponding to frequency f3 and a signal component corresponding to frequency f1 are obtained from a 3fHBPF11 and a fHBPF13 respectively. These signals are detected by detectors 12, 14 and supplied to a subtractor 15 as 3fH and fH error signals respectively. From the difference of these signals, an ATF error signal E is formed. The ATF error signal E is digitally integrated by an AD converter 21 and a microcomputer 22 to improve its SN. The momentum (a) is controlled so that the integrated value, i.e. a stop error E, shows zero to attain noiseless intermittent driving slow motion reproducing.

Description

[Detailed description of the invention]

[Field of Application of the Invention] The present invention relates to a variable speed InIn device for a VTR, and particularly to a variable speed production device for a VTR that performs intermittent drive of a magnetic tape and slow motion motion. [Background] In the rotating head helical scan VTR K,
Conventionally, some kind of synchronization signal is recorded on a magnetic tape during recording, and during reproduction, 611 synchronization signals are generated to control the rotational phase of the gear gun or rotary head cylinder. That is, a servo circuit performs tracking control based on the synchronization signal so that the co-rotating head correctly traces the video signal recording track of the magnetic tape. This method of performing one tracking control roll (
As for the servo method), it is usually a control method.

[A method (CTL method) is used in which a synchronizing signal 1n (pulse signal) with twice the cycle of the vertical synchronizing signal, called the I-rule signal (hereinafter sometimes referred to as CTL), is written at the end of the tape. ing. With the CTL method using this control signal, no matter what speed μ- the 11 magnetic tape is run intermittently,
The absolute phase between the detected 7'CCTL signal and the ad recording pattern on the magnetic tape is uniquely determined. For this purpose, for example, a magnetic tape that is stopped at a noiseless still state can be instantaneously driven 7L lines by intermittent drive until it reaches a noiseless state one frame later, and this operation is repeated at appropriate time intervals to achieve a noiseless tape. Slow motion 7N was easily implemented by using the CTL method to perform stop control including driving the cab stan motor and reverse braking after the detection of CTLiQ by a predetermined time delay. , a method using a CTL signal, but as another servo method, instead of the CTL{I<>3, four types of frequencies fl+f! are used as synchronization signals. +f□f4 pilot signal,
Method of superimposing recording on video recording (pilot method)
In this pilot method, a tracking error signal is obtained from the 1H signal of the caterpillar pilot signal while the loss tape is running or stopped, and the intermittent drive of the magnetic tape is controlled using this information. However, unlike normal playback, where the 1-rank engine is passed through a low-pass filter with a sufficiently large time constant and the YABO control is performed on an average basis, a high-speed response such as intermittent drive is required. In case A1, the ST1 ratio of the tracking error signal is worse than that of the CTL method described in IIlr, in which the information of the position signal is condensed at one point. Therefore, in the pilot method, the noiseless intermittent J! 14! jb could not be realized.Furthermore, there is another drawback as follows: in the case of the CTL method, the CTL multiplied signal has a period of 7 frames (2 fields). 111 is included,
While the intermittent drive feed of 1 frame 1 and 1 is "J ilhi, γ", in the pilot method it is 1. For example, the above [7, f, % f, 04 frequency by 11] fil'
If more than 3 are used, the synchronization Iba signal period is 27 rams (47 rams).
{-/Redo). For this reason, intermittent drive feeding every two frames is efficient, apart from the problem of SN deterioration, that is, noise performance, but it is said that it is difficult to realize intermittent drive feeding every 1 array. 1. [Object of the Invention] It is an object of the present invention to eliminate the drawbacks of the prior art described above, and to provide detailed information for each frame even if a regenerated pilot signal is used, as in the case of using a CTL signal. Intermittent drive feeding is possible, and noiseless intermittent 44
To provide a variable speed control device for a VTR capable of slow motion reproduction. [Summary of the Invention] The first feature of the present invention is that, as is clear from FIG. 1, which is a functional block diagram showing the overall schematic configuration, the first feature of the present invention is that pilot signals of several types, which correspond to 5% of the frequency, are combined into one type. By reproducing the pilot signal of the PI tape recorded on each video track at a constant period, u) In the speed change control device of a 9-rotation head helical V-Yang type VTR with 2-speed control control. , K ts + Jruf during the scheduled period of suspension of the magnetic tape
iii Extracting the pilot signal Pi 1] Soto signal J
1ν extracting means 6, extracting pilot signal components having frequencies corresponding to two of the extracted pilot signals from the local frequency signal having a predetermined frequency; pylon) (a tracking error signal output circuit 7 that outputs an ATF error sign having two tendencies depending on the mode in which the magnetic tape is stopped from the l/bel difference for the Q pk; A control signal supply means a for supplying a control signal for selectively switching the local frequency (N number) to the number processing circuit No. 1; A stop error generator IRb that creates a stop error corresponding to the amount of deviation of the magnetic tape from the state, and a tape fJSl that determines the number of magnetic tape feeders during the next intermittent drive based on an integral multiple of the planned track pitch. Based on the feed inertia determining means C and the ATF error signal having the two tendencies,
Is the mode in which the magnetic tape is stopped, the stop error creation hand gt b , K , ? ...Accurately calculate the stopping error! The mode determining means d determines whether or not the mode is set to 141, and the mode determining means d calculates the stop error by
When it is determined that the mode is such that the stop n difference creation means bK can be obtained, the ATF error signal is supplied to the stop n difference creating means bK, and on the other hand, when it is determined that the mode is such that the stop n difference cannot be accurately obtained, the first tape Based on the stop error difference obtained by the switching means e for selecting the feeder and the stop error creating means, the first tape feeder is corrected by a predetermined correction amount so that the difference is offset. a second tape feed amount determining means f for determining the feed and sweep of the magnetic tape during the next intermittent drive; and II! for busy running the magnetic tape. <Motor power I(,
, 6 capstan motor 5; a frequency detector 16 that outputs the number of pulses corresponding to the 150 rotations of the capstan motor; and a frequency detector 16 that detects the tape feed amount by counting the number of pulses, and tape feeding armpit determining means c;
+iil &! :1 v 21 Yapstan motor drive means g that applies driving force to the Fustan motor 5
The point is that and . Also, from FIG. 2, which is a functional block diagram showing the overall outline of the second feature of the present invention, Il! The number g with different frequencies, like lj! By reproducing the pilot signals of the magnetic tape in which one type of pilot signal is recorded on each video track at a constant period, the variable speed of the helical scan type VTR is realized. In the control device, a pilot output means 6 for extracting the pilot signal while the magnetic tape is stopped for a scheduled period.
And, among the local frequency multipliers 3 having a plurality of predetermined frequencies, a frequency corresponding to two predetermined ones of the extracted pylon toy No. 1 is generated by a local frequency signal having a specific frequency. A'l'F error signal having two tendencies according to the mode in which the magnetic tape is stopped is outputted from the level difference between the two Pyroft No. 18 components. a drugging error signal processing circuit 7; a control signal supply means 8 for supplying a control signal for selectively switching the local frequency signal of the plurality of frequencies to the drug processing error signal processing circuit; A stop error creation means for creating a stop error corresponding to the amount of deviation of the magnetic tape from a normal noiseless state while the magnetic tape is stopped based on the ATF error signal, an ATF error signal having the above two tendencies. On the basis of the,
a mode determination stage d for determining whether or not the mode in which the magnetic tape is stopped is a mode in which the stop error can be accurately obtained in the flf+period stop error creation means; and the mode determination means d determines the stop error. If the mode is determined to be one in which the minute cannot be obtained accurately, the Q l-1-cal frequency signal is transferred to the other 7r! With a constant frequency of i, the AT'F error that can accurately obtain the stop error (in order to obtain the it number,
This is canceled out based on the stop error generated by the output r1 of the control signal supply means a and the split Fl signal conversion means which converts the output r1 into another control φ11 signal, and the stop error created by the stop error creation means. (determining the feed rate of the magnetic tape during the next intermittent drive so that the feed rate of the magnetic tape is determined during the next intermittent drive) - single feed amount determining means f; a cab stan motor 5 that provides a driving force for running the magnetic tape; and the cab stan motor 5. A frequency detector 16 outputs a number of pulses according to the rotation of the tape. l
In order to detect this and drive the magnetic tape intermittently until it becomes equal to the feed amount determined by the tape feed amount determining means f,
The present invention is characterized in that a cab stan motor driving means g is provided to provide driving force to the cab stan motor 5. [Embodiments of the Invention] The present invention will be described below with reference to the drawings. FIG. 3 is a block diagram showing an embodiment of the vTl/IjJ speed change control device of the present invention. In FIG. 3, 1 is a magnetic tape, 2 is a cylinder motor, 3 is a rotating video head, 4 detects the rotational phase of the cylinder, and a servo circuit 17 outputs a one node switching signal swa.
5 is the cab stan motor, 6 is the bidet blade, and a signal circuit for extracting the low frequency component (pylon l (M number)) from the output of the blade 3. A dragging error signal processing circuit using a pilot method, 8 is a band pass filter (BP) for passing pilot No. 43 having four frequencies P, which will be described later.
F), 9 is a mixer that mixes the outputs of the local frequency generator 10 and BPF 8, and 11° and 13 are the difference between the specific local frequency and the frequency of birosotoin number n, which is 3f+, respectively.
3fo panned pass filter (3f++Il)'F'J that selectively passes the signal that becomes + +fu to. 4, which is a bandpass filter (fIIBPF), where fl+ indicates the horizontal synchronization frequency, 12.14 is a detector, 15 is a subtracter, 161 is a frequency detector, and 18 is an intermittent drive. III control circuit, 19 local frequency change section, 20 stop condition determination section, 21 A
Dco/verter 22 is a control microcomputer consisting of a CPU 23, a pass line 24 and a memory 50;
5 is an electronic switch. Here, the operation of this embodiment will be explained. FIG. 4 is a pattern showing an example of the relationship between one rack pattern of the magnetic tape 1 and the trajectory of the head 3 (head trajectory) to explain intermittent drive. It is a diagram. Note that in the figure, hatched areas A, B, and A indicate the head trajectory. In this embodiment, each trunk pattern in FIG.
u), fs(10,5fu), f, (9,5f+θ) are omitted in the above order. Also, Figure 5 (su~(3)) and Figure 7 (υ~(3)) are A waveform diagram (time chart) showing an example of the waveform signal of each part in FIG. 3, FIG. 5 (4) and FIG.
Figures and! Figure 88 shows the normal noiseless state (l
FIG. 3 is a characteristic diagram showing an example of the relationship between the deviation value ΔX of the tape l from X=o) and the corresponding stop error lP2. In the following explanation, head trajectories A and B in FIG.
, A... will be explained using the so-called field tilt system that reproduces with the same unmanu head 3.
The same can be considered in the case of normal arene stills. In FIG. 3, the microcomputer 22 controls the local frequency changing unit 19 to set the local frequency output from the local frequency generator io to f2,
With the frequency f being supplied to the mixer 9, the signal circuit 6
When the pilot signal extracted from the BPF 8 passes through the BPF 8 and is completely supplied to the mixer 9, in this embodiment, 3fo
From F11, the signal component corresponding to frequency f8 is fu
Signal components corresponding to the frequency f are obtained from the BPFl 3, and these signals are sent to the detector 12.
, 14, respectively, were detected by "fnnnilla-"
Moon and fl+ become error signals. These error signals 1
ATF (Aot
o+mt1cTrack Finding) An error signal E is formed. By the way, while the magnetic tape 1 is stopped, the Pideme head 3
By tracing the trunk in which the pylon 1 signal at the position of the head trajectory A in FIG.
The signal and fn error signal are shown in WIs diagram (1) l (
2). As a result, the ATF error signal E output from the subtracter 15 has a waveform as shown in FIG. 5(3). Here, while the magnetic tape l is stopped, the video tape 3 is t
It will be qualitatively explained that the 3ft + machine error signal and the fn error signal as shown in Figure 5 (1) and (2) K are obtained by tracing the position to the head trajectory in Figure JS4. When the video head 3 traces the head trajectory portion of FIG. 4 from bottom to top in the direction of the arrow in one field time, the 3fo signal output from the detector 12 in FIG.
As mentioned in 1, the machine error signal is a signal component corresponding to the frequency f, so as is clear from Figure 4, this signal level is large at the bottom of the head trajectory A, and gradually becomes linear. 1, that is, Figure 5 (1
) will result in a waveform signal as shown in Note that the time for one field is the vertical synchronization during normal playback (A of the period of the JT number, 16 in the NTSC system).
．． 7ms, and in FIG. 5, it is time t. ~ [corresponds to the period of 1. fn output from the detector 14 in FIG. 3: the f-ler signal, that is, the in-n component 1 corresponding to the frequency f, similarly, ! As shown in Figure (2), IFt will be a waveform signal that increases exponentially. Therefore, AT formed from the difference between these error signals
As mentioned above, F error No. 05 E becomes a waveform signal that decreases almost linearly as shown in FIG. 5(3). This ATF error signal E is generated at the time of the l field, that is, at time t. -1, the electronic switch 25 is jff
ll), is digitally integrated by the AD converter 21 and the microcomputer 22 for s/'Nae. This digitally integrated value is equivalent to the area S shown in (3) of the ylS5 diagram and the S20 difference (S+St). If this is expressed as the stop error ll, this corresponds to the deviation ll:lx of the tape 1 with respect to the video head 3, so it shows the relationship between the stop error lE and the deviation ゜jx of the tape 1. Characteristic curve (stopping error jE-tape 1
The deviation angle ΔX characteristic curvature) is as shown in FIG. That is, in FIG. 6, when the head trajectory A traced by the video head 3 shifts to the right from the position shown in FIG. This shows that since the level of the 3flI/2- signal increases, the stop error jl also increases. The $-1fi6 diagram is normalized by the frame pitch P. You can get it as above! @5 Diagram (3) ATF work 2-
The stop error 7B corresponding to the signal BK is at time t. From t8
Since the result of digital integration between 1 and 2 is obtained for the first time, time 1 in FIG. Then, a new lE is determined according to the area difference (S, ~8.). Therefore, here we call this 'E
11, lE before time 81t1, which is not shown in FIG. 5(4), represents the stop error jEn, f corresponding to one field before the time adjustment. As is clear from the above explanation, there is a problem with this embodiment. In order to perform noiseless intermittent drive slow motion 3rl generation, when the tape 1 is intermittently driven, or equivalently, when the video head 3 moves from the head trajectory A to B in FIG. Then, it is sufficient to control the moving shell so that the stop error lE becomes zero. . Therefore, in this embodiment, the pulse #! which is the output J of the frequency detector 16 which detects the 50 rotation speed of the capstan motor is used.
1. When counting FG inside the microcomputer 22, a predetermined tape 1 necessary for 17-frame intermittent drive is counted.
According to the moving lid. The S pulse number is counted by taking into account the Nox number corresponding to the stop error ΔE,
Based on this, the Yapstan motor 5 is controlled based on the data FG0 corresponding to the number of pulses corresponding to the J predetermined moving pieces of the tape 1 necessary for the l-frame intermittent drive. The data (F
The motor 5 of the cab 7 is controlled by counting the number of four pulses FG according to the number of 4 pulses FG. The driving of the capstan motor 5 is stopped in the following manner. First, the capstan motor 5 is driven by a capstan motor drive signal (CMR) from the microcomputer 22.
UN) K j
This is done by the output from 4m17. In addition, the capstan motor 5 is stopped using the above-mentioned data (FG0
After the microcomputer 22 counts the pulses #FG corresponding to G), the computer 22 outputs a carburetor tongue motor reverse braking signal (REVER8K), which is controlled by the output from the servo circuit 17. . By the way, the problem here is that the video head 3 is equivalently moved from the head trajectory B to A in FIG. As an evaluation, the movement s should be adjusted so that the stop error lE in the head trajectory AKG after movement becomes zero.
*bf: This is something that cannot be controlled. This will be explained below. When the video head 3 traces the head trajectory B in FIG. 4 from bottom to top in the direction of the arrow, the 3fn error signal output from the detector 12 in FIG. 3 is as described above. Since it is a signal component corresponding to frequency fj, the fourth
As is clear from the figure, this signal level of 1 corresponds to the head trajectory B.
It is small below , and gradually increases linearly. 1, that is, a waveform signal as shown in FIG. 7(1) is obtained. On the other hand, f output from the detector 14 in FIG. The Bra\J component corresponding to the error (W), that is, the frequency f, is obtained in the same way, resulting in a shaped signal that decreases linearly as shown in Figure 7 (2). Therefore, AT formed from the difference between these error signals
In this case, the F error signal E becomes a waveform signal that increases almost linearly, as shown in FIG. 7 (3), which is exactly opposite to the trend of the waveform signal shown in FIG. 5 (3). . The characteristic curve of stop error j13 - deviation factor of tape 1 x obtained as described above based on such a waveform signal is as follows:
The result will be as shown in Figure 8. In other words, the tendency is exactly opposite to the characteristic curve shown in FIG. As a result, for example, if the head trajectory B traced by the video head 3 deviates to the right from the position shown in FIG. will decrease. Therefore, based on this stop error 7E, the movement qb
When controlling the head trajectory after moving, it is impossible to make the stop singing difference lE to zero, that is, in this case, 1 frame intermittent drive and 2
Therefore, it was impossible to stop the magnetic tape 1 in a noiseless state. In addition, from time t2 in Figure 157
A period of 1R indicates a 1F yield period. Therefore, in order to solve the above problem in this embodiment C#'i, the following measures were taken. That is, a stop state determination section 20 is provided in the intermittent drive control circuit 18, and the hand For example, the start p of the l field shown in FIG. 5 or FIG. 7 is determined based on the switching signal 5W30.
At time t0 or t, the determination unit 20 in 61j
The ATF error signal E input to the
This here corresponds to reference level 0 in FIG. 5(3) and FIG. 7(3). ), the video head 3 determines l-, which is on the sword 1B on the head trajectory A. Then, the ATF 2-signal E is set at the predetermined level E.
. In the above case, the full output of the signal that turns the switch 25 into the 1-indication state is completed. That is, in this mode, since the position of the video head 3 is on the \\ gutter trajectory A, the video head 3 is equivalently moved from the head trajectory A to the head trajectory B as described above. By doing this and making corrections,
One frame intermittent driving F# can be performed in a noiseless state, while the ATF error signal E is at a predetermined level E-
If it is below, the electronic switch 25 is switched so that the electronic switch 25 is forced to output a 0 level signal. This is equivalent to forcibly setting the ATF error signal E to the θ level potential, so the stop error jp becomes 0, and as a result, the pulse OF'G to be counted by the microcomputer 22 is The number of pulses corresponds to a predetermined amount of movement of the tape l required for driving. . That is, in this mode, since the position of the video head 3 is on the head trajectory B, the video head 3 is equivalently moved from the head trajectory B to the head trajectory A as described above. In order to reduce the amount of time required to move the tape 1, the amount of movement of the tape 1 was set to the standard value for 1 arene/intermittent drive. Next, a second embodiment of the present invention will be described. This second embodiment corresponds to the l(1:)W implementation 1f1 described above.
1 is different from the intermittent drive control circuit 181 in FIG.
The only difference is that the AD converter 31 shown in FIG. 9 is replaced with a one-chip microcomputer 30. In addition,
In FIG. 9, 32 is a CPU, 33 is a suffix, and 50 is a memory. Hereinafter, the operation of this second embodiment will be explained with reference to FIG. 10. (1) in FIG. , C-turn diagram similar to Fig. 4, (
2) is a time chart showing an example of a change in the stop n difference ΔE, (3) is a time chart showing an example of a change in the speed (CM speed) of the CAGSUKUN motor), (4) and (5) are CMRUN (6) is a time chart showing an example of a change in the displacement of the magnetic tape l normalized by the frame pitch P. Note that period (1) in the figure is the time during which the video head 3 is stopped along the head trajectory with respect to the tape running direction; From the state, the head trajectory B is changed by intermittent driving.
The period (E) during which the video head 3 is stopped on this B after moving to the above head trajectory B is
From the above stationary bond, the head trajectory is driven by intermittent drive!
, respectively, indicate the amount of time this person remains in a stopped state after moving $. Also, Ill in (2) of the same figure,
'E2 and JE. shows each stop r difference aB when the video head 3 is in a stopped state at each il on each head trajectory A, B, and A. 11 is a flowchart 1 for explaining the operation of this second embodiment. In the following explanation of the operation, the parts other than 1, knob 1, and 0 are ,+ijl mentioned! Tll'
:! ; ii It is the same as pH, so it will be omitted. In the example of Heisei 2, 1 arene・ll'l missing #!
<%Iry When the low motion one playback is started, the head switching signal SW3 is activated in the switching no.2 blib S1.
Determine whether o has changed. When it is determined that a change has occurred, the process proceeds to step S2. In step S2, from CP■) 32, vanu line 33
, the local frequency generator 10 outputs a control signal (No. 8 (Local)) that allows the local frequency generator 10 to generate a local frequency of frequency f2. As a result, similarly to the first embodiment, the 30th video head lit When the video head 3 is on the head trajectory A9hi in FIG.
In case of B mode), A similar to that shown in Fig. 7 (3)
TF Niji-1a No. E is obtained. . Therefore, in step S3, the head switching signal SW
The A detected by the AD converter 31 at almost the same timing as the rising or falling timing of 30.
The level of the TF error signal E is set to a predetermined level E. (Here, Eo=O) and determine whether it is greater or less than that. That is, here, ATF error signal E
If it is determined that EoiM is above the predetermined level, the mode is A mode, and if it is determined to be below the predetermined level, it is B mode. Here, for example, if it is determined that it is A mode, Ndesog S4
Proceed to. Here, Local is identified so that the local frequency generator 10 can generate a local frequency of the same frequency f as in step S2. After that, the process advances to step S6. In step S6, one field of the ATF error No. 8 E is digitally integrated by the AD converter 31 and cPu 32, and the resulting value, that is, the stop error JE is detected. Is the stop error lE detected in , for example, negative like lEl in period (1) in FIG. 10 (2)?
Or, it is determined whether the condition of period Q or lE is correct. As a result, j El
In step S8, 1 arene, data FGo corresponding to the number of pulses and pulses corresponding to the predetermined movement amount of the tape 1, which is essential for intermittent drive, are set to pVJ. By adding the unit Jl:jFG corresponding to the number of corrected pulses FGk determined in
FGN corresponding to the number of pulses FG to be output from 6,
I put it on. That is, in general, the pulse aFG is such that the next 17 frames of intermittent driving can bring the noise-free state closer to the state.
Set the data FGN corresponding to (FGo + ΔF'G) as (FGo + ΔF'G).Next, in step SIO, in order to actually perform intermittent driving for one frame, data is sent from the CPU 32 via the pass line 33. , high level 'H#) CMRUNk output. As a result, the capstan motor 5 is driven. In step 811, the Yapstan motor 5
The frequency l11. The number of pulses FG output from the detector 16 is counted. In FIG. 10, time t in period 01). Counting will start from now on. In step S12, it is determined whether the number of pulses FG exceeds the data FGN. Sunawa'
b, -ff), the number of pulses 1'i'G is)j+J
Determine whether or not the take FGN f has been exceeded. SoL-'(, Hull, x, aF G Ka, j+if H
If it is determined that the value exceeds t r -t E'GN, f, the process proceeds to step s13 tr. What is the time when it is determined that the above-mentioned time has been exceeded? In the lth 0th figure, it is time t. In step S13, in order to apply reverse braking to the *Y displacement motor 5, the CPU 32 outputs REVER8E of the scheduled M+)0 high level town Il via the pass line 33 to i6°ilo figure'tt, 611 de f nod. The period is (tw'-t4). y, f y FuS14 Teh, +iQ aselfP >F
Jtll Determine whether the amount of money has elapsed or not. 7L waits at the cow. If the scheduled period has elapsed, the process advances to step S15. 7, f Tsubu S], 5te is CMRUN and ILEV
EILSk: Set both to KO-level %L# and stop +ilJ deactivation. +7) CMRUN and REVER8EiC The CM speed is gradually accelerated from time L0 to a constant speed, then gradually increased from time t4, and then comes to a halt at time t4. In the stem game S16, after the scheduled time t8 has elapsed, the process returns to the green stem game 81. Note that the speed of fine slow playback is determined by this scheduled time t8. The following explanation was based on the vh case determined to be in A mode in step S3, but for example, when the same person is driven as described above and it is determined to be in B mode, the stopping error I here Ex Vt, as mentioned above, since the characteristics are opposite,
It does not represent the correct stopping error. Therefore, in FIG. 11, step S3 is replaced by step S.
It was decided to proceed to Step 5 and perform fixed-leg feeding of the magnetic tape 1. That is, in step S5, data FGN corresponding to the actual number of pulses FG in period Make sure to set it to . Then, the process proceeds to step 810. The subsequent rtit in flowchart 1 is the same as nl n+. . In addition, in the above explanation, the suspension 1III in period (1)
If the difference lE weight is negative in step S7, iIj
If 9 is positive, the process advances from step S7 to step S9. Then, in step S9, the data FGN, which is different from the step S8 described above, is changed to the data FGN corresponding to the number of pulses FG corresponding to the predetermined movement of the tape 1 necessary for intermittent driving of one frame. "Go; 711 et al., 1 [, Set as data obtained by subtracting the jp position ΔFG corresponding to the corrected pulse number FG determined in 1. In the case of C, generally,
The data FGN corresponding to the number of pulses FG that approaches the noiseless state by the next one-frame intermittent drive is (FG
Set o-jF (n). Then, the process proceeds to step SIO. The subsequent flow of the flowchart is the same as described above. Note that in this second embodiment, FG0=41°ΔF
An example of the specific time relationship of each part when G=1 is set is shown in numbers below the waveform in FIG. 10 (5). In the above, it is determined whether the mode is A mode or B mode, and depending on the result, control is performed so that the stop error ΔE becomes zero, or whether the fixed view of the magnetic tape 1 is advanced by one frame. We have explained the method for selecting. Incidentally, similarly to the second embodiment, the one-chip microcomputer 30 shown in FIG. 9 is used in the intermittent drive control circuit 18 shown in FIG. It can be controlled so that the stop error IE becomes zero. This third embodiment will be described below. FIG. 12 is a flowchart for explaining the operation of the third embodiment2.The difference between FIG. 12 and FIG. 11 is that when it is determined that the mode is B in step 33, , Local, local frequency generator 1
0, we are about to switch so that the '40 frequency is obtained. Therefore, this difference will be explained below. In step S3, if it is determined that the mode is B, in this third embodiment, step 820K is performed. In step 820, the CPU 32 sends a message to the pass line 33.
via the local frequency generator IO, step S2
Switch LocIIl so that the local frequency of f4 can be generated by replacing the local frequency of f2 at λ,
Fix it to this. By doing this, in this third 5!1: example, the signal component corresponding to the frequency f is obtained from the 3fnBPF 11, and the No. 48 component corresponding to the frequency f3 is obtained from the f++BPF 13. Therefore, the 4*wavelength signal 12, 14, and the 3f11 error signal and fl+ error signal, which have the same tendency as shown in FIG. The trend of the ATF error signal E outputted from the device 15 is also similar to that shown in Fig. 5 (3).In other words, in this embodiment of IJ!3, even if the error occurs in B mode. , in step 86, the exact stopping error ΔE
can be detected, so the process can proceed to step S6. The subsequent flow of the flowchart is exactly the same as that shown in FIG. 11, so a description thereof will be omitted. [Effects of the Invention] From the above explanation:) As is clear, according to the present invention, even when using a regenerated pilot signal, fine-grained control of each frame can be achieved even when a regenerated pilot signal is used. It enables intermittent drive feed, and has the effect of providing 1J of noiseless intermittent drive slow-motion playback comparable to the CTL method. According to the third embodiment, the tube can be driven intermittently to a noiseless stop state every arene, so the above effect becomes remarkable.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram to clearly demonstrate the first feature of the present invention, FIG. 2 is a functional block diagram to clearly demonstrate the second I timing of the present invention, and FIG. 3 is a functional block diagram of the VTR of the present invention. A block diagram showing one embodiment of the circular hole speed control device, FIG. 4 is an intermittent jgiU
A pattern diagram showing -1++1 of the relationship between the track pattern of the magnetic tape and the head trajectory to explain the movement, +TI
Figures 5 (]) to (3) and i7 (]) to (3) are the waveforms of various parts of Figure 3 (time charts showing the 11th bar of No. N, Figures 5 (4) and 7), respectively. Figure (4) shows the stopping error Δ
One of the changes in E! 1f! Figures 6 and 8 are characteristic diagrams of tape deviation FAΔX-stop error ΔE. Also, FIG. 9 is a pronk diagram of a one-chip microcontroller used in place of the intermittent drive control circuit shown in FIG. 3, and FIG. FIG. 1 is a diagram for explaining the operation of the second embodiment, in which (1) is a pattern diagram similar to that in FIG.
) is a time chart showing the ashing of the stop l difference ΔE, (3) is a time chart showing an example of a change in CM speed, (4) and (5) are CMJtUN and RE
Time chart showing an example of changes in VEIltSE), (
6) A time chart showing an example of changes in the movement of the magnetic tape normalized by the frame pinote is shown. 11th
FIG. 12 is a flowchart for explaining the operation of the second embodiment, and FIG. 12 is a flowchart for explaining the operation of the third embodiment. 1... Magnetic tape, 2... Printer motor, 3...
・Rotating video head, 4...Tack head, 5...
Capstan motor, 6... (N circuit, 7... Tracking error signal processing circuit, 8... BPF, 9...
...mixer, lO...local frequency generator, l.
・3fuBPF, 12, 14...Detector, 1
3...fIIBPF115...Mfi device, 16...
・Frequency detector, 17...' Ribo circuit, 18...
19...Local frequency change unit, 20...Stop state discrimination ((, 21, 31...A
D computer, 22...1' Microcomputer, 2
3.32...CPU, 24, 33...Pass line, 25...Electronic switch, 30 ・1 Chinog Microcombinator, 50.60...Memory agent Michihito Hiraki, patent attorney Fang 1 1 J'2:, 1 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 Fig. 6 Fig. 9 -1“0

Claims (1)

[Claims] (1) Several meters of pilot signals with different frequencies are 111
By reproducing the pilot signal of the magnetic deso recorded at a constant cycle on each bidet first rack,
In a transmission control F1 device for a rotary head helical scan type VTR that performs hJ transmission control, a pilot signal extraction means [7 means, n
01 by a local frequency signal with a constant frequency r
) Extract pilot signal components having frequencies corresponding to two predetermined ones of the extracted pilot signals, and calculate the two pilot signal components corresponding to the stopped mode of the magnetic tape from the level difference between the two pilot signal components. A with two tendencies
a tracking error signal processing circuit for outputting a TF error signal; a control signal supply means for supplying a control signal for selectively switching the local frequency signal to the tracking error signal processing circuit; , means for creating a stop error amount corresponding to the deviation of the magnetic tape from the normal noiseless state during the stop of the magnetic resolution, and an integer for one track pinch. A first tape feed I determining means that determines the magnetic tape feed number at the time of the next intermittent drive, and an ATF error signal that determines the above two trends.
The mode in which the magnetic boop is stopped is
When the mode flJ constant means for determining whether the stop error can be accurately calculated in the 11th valley is determined to be force/old, and the mode determining means determines that the mode is a mode in which the stop l difference can be accurately obtained, The A″rFrF Golar multiplication stop error is supplied to the stop error creation means, and if it is determined that the mode is such that the stop L error cannot be accurately obtained, the previous Ik! is switched to select the first tape feeder. Based on the means and the stop error amount obtained in the stop correct error amount creation means,
a second tape feed amount determining means that corrects the first tape feed amount by a predetermined correction amount so as to offset this, and determines the feed pattern of the magnetic tape during the next intermittent drive; a capstan motor that provides a driving force to rotate the capstan motor; a frequency detector that outputs a number of pulses according to the rotation of the capstan motor; and a frequency detector that detects the amount of tape feed by counting the number of pulses; or a capstan motor drive means for applying a driving force to the capstan motor in order to drive the magnetic tape intermittently until the feed rate becomes equal to the feed rate determined by the second tape feed rate determining means. -J transmission control device of VTlt, (
2) The variable speed control device for a VTR as set forth in Patent No. 1, wherein the +itl pilot signal is derived from a different 41i frequency. (3) The capstan motor mentioned in 6i1 stops when the capstan motor 7-e stops [at the end of the operation J91 11111?
Claim 1 of Claim 11I or younger brother 2 which is characterized by superimposing the Ygustan motor reverse braking i4'+ on the Yagustan motor drive signal
+il summer speed control device of Vi'lζ described in section 1 (4) Several types of pylons 1 and Iba with a frequency of 4
By reproducing the above-mentioned bironograph signals recorded on the magnetic tape at a constant cycle on each type of video track, d' speed change control is carried out to the i' speed change control film device of a 9-rotation linear scan VTR. At the same time, when the scheduled period of the magnetic tape is stopped + 1, a pie is taken out to extract the pyronotation signal which is inserted into the magnetic tape.
The extracted pi! is detected by the p extraction means and a local frequency signal having a specific frequency among the U-cal frequencies a{11 having a plurality of predetermined n wave numbers. The pilot signal components having frequencies corresponding to two predetermined ones of the one-note signal are extracted, and two trends depending on the mode when the magnetic tape is stopped are determined from the level difference between the two two-note signal components. a torasoking error signal processing circuit that outputs a certain ATF error signal;
A local frequency signal f of DIs notation 4 numbers 1 number wave number is applied to one signal processing circuit.
A control signal supplying means for supplying a control signal and a stop error corresponding to the amount of deviation of the magnetic tape during stoppage of the magnetic tape based on the ATF signal. Based on the error amount creation means and the ATF error signal having the two tendencies, it is determined whether the mode in which the magnetic tape is stopped is a mode in which the stop error amount can be accurately obtained by the stop error amount creation means. When the mode determining means and the mode determining means determine that the mode is such that the stopping error cannot be accurately obtained, In order to obtain an accurately obtained ATF error signal, the output of the control signal supply means is converted into another control signal converting means, and the stop error component obtained by the stop error component generating means is used. Based on, so that this cancels out,
a tape feed amount determination step 1 which determines the feed m of the magnetic tape during the next intermittent drive; A frequency KLI.detector outputs the number of pulses corresponding to the 161 rotation of the tape, and detects the tape feed amount by multiplying the number of pulses n11 by the number of stitches. In order to drive the magnetic tape intermittently until the magnetic tape becomes equal to the voltage, a scratch press motor driving means is provided which applies a driving force r to the V-pressure motor. A variable speed control device for a VTR, characterized by comprising: (5) The pilot F signal or the 4th grade p. The transmission control device for a VTR according to claim 4, characterized in that: A patented modification 1I Garirin device characterized in that it is made by superimposing a capstan motor reverse braking IP No. 1 on a drive signal.