JPH04358301A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To optionally set data capacitance, to record for a long time and to detect a track tilt angle in high accuracy by providing a mode setting means, a recording data amount setting means, a track length forming means and a tape feeding speed variable means. CONSTITUTION:In a signal processor 102, unnecessary data is removed from a video signal from a terminal 101 and the signal is data-compressed in accordance with a recording data amount indicating signal from a mode setting device 105. The video signal is added a detecting code to correct an error at the time of reproducing and coded to recording data, thereafter, the data is sent to a head 109 through a recording amplifier 103. The track inclining angle matching recording data amount and the tape sending amount at every one track in prescribed rule are calculated in the mode setting device 105. A tape speed controller 107 controls the motor 101 of a capstan 111, and a track inclining angle controller 106 moves the head 109 upper and lower by using, for example, a head actuator and varies the inclining angle.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording and reproducing apparatus for recording and reproducing information by forming inclined tracks divided into predetermined lengths on a recording medium.

0003

[Prior Art] For example, the band of an NTSC television signal is 4.2 MHz, but when this is converted into digital data, it is 115 Mbit/s (=4 fsc x 8
bit This is a value obtained by sampling at a frequency four times the frequency of fsc and quantizing the sample value with 8 bits. Here, fsc is the color subcarrier frequency of 3.58 MHz. ) is a huge amount of data. When image data is converted into digital data in this way, it becomes a huge amount of data, and it is difficult to record this data with a system such as a conventional home VTR. Therefore, image compression technology is generally used to reduce the amount of data. In image compression, the image quality at the time of image decoding is determined by the ratio (compression ratio) between the amount of input data and the amount of output data.

[0004] When setting a long-time mode on a digital VTR like current home analog VTRs, it is conceivable to increase the compression ratio to reduce the amount of data more than in the standard mode, thereby increasing the length of time.

FIG. 26 shows an example of a digital VTR that performs such image compression. Figure 26 shows 2
The basic configuration is a four-channel head, and the system uses two channels during standard mode recording and only one channel during long-time mode recording. Therefore, this system has two channels of signal processing systems and electromagnetic conversion systems. That is, during standard mode recording, the recording signal input to the terminal 1 is divided by the channel division circuit 4, and then one of the recording signals is divided by the recording signal processing circuit (1) 5, the recording amplifier 7, and the recording/playback switch 14. The recording/reproducing head 16,1 passes through the recording side (R) of
The other recording signal is supplied to the recording signal processing circuit (2) 6, the recording amplifier 8, and the recording side (R) of the recording/reproduction switch 15 to the recording/reproduction head 17, 1.
9. That is, two channels of recording signals are alternately recorded on a magnetic tape (not shown) by four heads 16-19. Further, during standard mode playback, one of the playback signals from the recording/playback heads 16 and 18 is sent to the playback side (P) of the recording/playback switch 14, the playback amplifier 12, and the playback signal processing circuit (1) 10 to the channel integration circuit. The playback signal from the recording/playback heads 17 and 19 is supplied to one input end of the recording/playback head 17 and 19 through the playback side (P) of the recording/playback switch 15, the playback amplifier 13, and the playback signal processing circuit (2) 11 to the channel. It is supplied to the other input end of the integrated circuit 9. Therefore, the four heads 16
The reproduction signals of the two channels from 19 to 19 are alternately reproduced, and as a result, the channel integration circuit 9 outputs temporally continuous reproduction signals. On the other hand, the recording amplifier 8 and the reproduction amplifier 13 can be turned on and off by a control signal from the channel number selection circuit 20, and during long-time mode recording and reproduction, the operation of the recording amplifier 8 and the reproduction amplifier 13 is turned off. , a one-channel recording amplifier 7, and a reproduction amplifier 12 are used. As a result, only one channel's worth of signals are recorded and reproduced on the magnetic tape during long-time mode recording and reproduction. Note that the channel number selection circuit 20 receives high and low level signals corresponding to switching between the standard mode and the long-time mode from the terminal 3, and in the long-time mode, these signals are sent to the recording amplifier 8 and the playback amplifier 13. A control signal is output to turn off the amplifier.

By the way, in a digital VTR that performs image compression as described above, the basic configuration is formed by 2 channels and 4 heads, and 2 channels are used during standard mode recording, and only 1 channel is used during long-time mode recording. This required a signal processing system and an electromagnetic conversion system for two channels. In addition, with this configuration, the ratio of recorded data capacity in the two modes, standard mode and long time mode, is fixed at 2:1, and data cannot be recorded at the best compression ratio that corresponds to the image quality. There was a shortage and surplus. Furthermore, if a multi-channel configuration is adopted, the ratio relationship of data amounts can only be set to an integer multiple ratio, and a complicated channel configuration is required to provide a complicated ratio relationship.

On the other hand, let us consider how to deal with mechanical systems such as drums and tape running systems. A conventional technique for reproducing tapes on which signals of different data amounts are recorded is described in Japanese Patent Application Laid-Open No. 62-33357. This publication describes a recording/reproducing device that has a fixed drum and a rotating magnetic head, and a lead that guides the lower edge of the magnetic tape on the fixed drum. discloses a method of providing leads having different lead angles. However, in this method, in order to accommodate any track angle, it is necessary to provide a large number of reeds on the circumferential surface of the fixed drum, and the reeds are formed unevenly on the circumferential surface of the fixed drum. As the number of drums increases, the difference in drum diameter between the leads formed on the innermost circumference and the leads formed on the outermost circumference increases, leading to worsening of contact conditions between the head and tape during recording and playback, and damage to the tape. These problems made it difficult to run the tape. In addition, due to manufacturing issues, it is difficult to provide a large number of leads exceeding the specified amount.
It was not possible to configure the system to support arbitrary tape formats.

[0008] On the other hand, when making a reservation for an answering machine, if the remaining tape capacity is insufficient for the recording time set in the standard mode, the V has a function of automatically switching to the 3x mode and recording.
HS (registered trademark) (Video Home Systems
em ) type VTR has been developed. The 3x mode of the VHS standard is designed to lengthen the recording time by reducing the tape feed speed to 1/3. Tape feed speed
Since it is 1/3, the recording track width is 1/3 of that in the standard mode. The track width affects the S/N of the reproduced signal by the square root, so if you switch to 3x mode,
．． The S/N deteriorates by 8 dB, which simply reduces the S/N of the reproduced image.
Although it cannot be applied to the above, the reproduced image also suffers from approximately the same degree of image quality deterioration.

On the other hand, consider a digital recording VTR. An example of the relationship between the S/N of the reproduced signal and the error rate is as shown in FIG. 27. Since the error rate is generally set to be about 10-4, the S/N of the reproduced signal is 19.
Conditions such as the recording wavelength and track width are set so that around 5 dB is obtained. Here, as above, change the track width to 1/3
Considering the realization of a long-time mode, the S/
N becomes 14.7 dB, and the error rate drops to about 10-2. However, in general, it is rare to use this data directly as a reproduced image, and before that, the reproduced image is created through an error correction circuit that improves the error rate. Therefore, let us further consider the correction ability of the error correction circuit. Figure 28
Figure 2 shows the characteristics of the error correction capability of the D-2 standard. Looking at the error rate after correction, if the error rate before correction is 10-4, it is expected to be 10-40 or less, but if the error rate before correction is 10-2, the error rate after correction is 10. -4 or higher, resulting in significant deterioration. Therefore, if the tape is automatically switched to the long time mode when the remaining tape capacity is insufficient during recording, there is a problem in that the error rate will not be improved much during playback even if error correction is performed.

In addition, in order to realize different tape formats with one recording/reproducing device, it is first necessary to deal with different track inclination angles.
There is one described in Publication No.-33357. In this example, one drum is provided with reeds at two different angles. However, it is necessary to set which lead is to be used during reproduction, and there is no concrete countermeasure against the complexity of selecting a large number of leads and the recovery operation in the event of a selection error. Therefore, for example, as a method for detecting that an incorrect lead has been selected and selecting an appropriate lead, a method can be considered that detects the number of tracks crossed during head scanning and detects the track inclination angle on the tape pattern. However, if there is a large difference in track inclination angle, the number of tracks to be crossed increases, and the azimuth loss due to the deviation of the azimuth angle increases, making it difficult to detect the number of tracks crossed depending on the presence or absence of reproduction output.

This example will be described with reference to FIG. First, let's consider the number of track straddles. This system has two formats: track a with a track inclination angle θa of 5° and track b with a track inclination angle θb of 10°.The tape recorded on track b is placed on the lead for track a and head scanning is performed. Then, at the end of the track, the head advances to a position shifted by a distance Z. All tracks in between are scanned across. Here, each parameter is set in accordance with the format of the VHS 2-hour recording mode, and the number of track crossings is calculated.

[0012] If the video full width B is 10.60 mm, then Z
=(B/tan5°)-(B/tan10°)=61.
04mm If track pitch P is 0.058mm, then track b
The tape feed amount x per track is x=P/sin
10°=0.33 mm Therefore, the number N of tracks to cross is N=Z/x=182.7 tracks. In this way, the number of track straddles changes greatly due to a slight difference in the track inclination angle. Next, let's consider the deviation of the azimuth angle. The azimuth angle α for both tracks a and b is determined by the angle formed by the lead formed on the drum and the head gap, and is not dependent on the track inclination angle. Therefore, if you mistakenly trace the track pattern of track b for track a,
An angular difference of 5 degrees between the two tracks causes a serious deviation, and a drop in output due to azimuth loss is unavoidable.

As described above, in a device that is capable of setting a plurality of lead angles, when the number of tracks crossed by the head is detected as a means for detecting the track inclination angle, it is possible to detect the number of tracks crossed by the head. However, considering that the number of track straddles changes greatly and that the output decreases due to azimuth loss, it is difficult to judge the track inclination angle by looking at the number of abdominal nodes in the envelope of the reproduced signal.

[0014]

[Problems to be Solved by the Invention] As described above, in the conventional technology, multi-channeling is unavoidable when recording signals with different data rates, and even if multi-channeling is achieved, the amount of recorded data is an integer multiple. It was only possible to change the ratio in increments, resulting in an excess or deficiency in the amount of recorded data needed. In addition, in mechanical systems, when trying to provide a large number of leads on one drum, it is difficult to obtain favorable conditions due to contact between the tape and the head, tape damage, etc., and the number of manufacturing steps increases and high-precision machining is required. There were many problems, such as the demands placed on it.

On the other hand, in digital recording, if the recording time becomes long and the tape feed speed is reduced to narrow the tracks, the error rate of the output signal will be reduced by processing the playback signal system such as error correction. There wasn't much improvement, and the signal had deteriorated significantly.

[0016] On the other hand, in an apparatus that needs to play back a tape in a format in which tracks with multiple inclination angles exist by recording using multiple lead angles, it is possible to select the optimal lead. As a means to do this, it is necessary to detect the tilt angle of the track to be played.
There was no effective means to detect this track inclination angle.

[0017] Therefore, an object of the present invention is to make it possible to set the data capacity for recording/playback per track to an arbitrary value by compressing the data capacity for recording/playback per track even in a single channel configuration, and to enable recording/playback compatible with any tape format. The object of the present invention is to provide a recording/reproducing device that has the following features.

Another object of the present invention is to provide a recording/reproducing apparatus which reduces the tape feeding speed in a long time mode, eliminates narrowing of the track, and does not deteriorate the error rate of the reproduced signal. .

Furthermore, another object of the present invention is to provide a recording/reproducing apparatus capable of detecting the inclination angle of a recording track when the inclination angle of the recording track and the inclination angle of a head trace during reproduction are different. That's true.

[Configuration of the invention]

[0021]

[Means for solving the problem] The invention according to claim 1 includes:
A recording and reproducing apparatus that records and reproduces data by forming inclined tracks divided into predetermined lengths on a recording medium, comprising: means for setting a recording time mode of data to be recorded on the recording medium; means for changing and setting the amount of recorded data per track according to the recording time mode; and means for changing the inclination angle of the track according to the recording time mode to set the amount of recorded data per track. The present invention is characterized by comprising means for forming the tape length, and means for changing the tape feeding speed in accordance with changes in the inclination angle of the track.

According to a second aspect of the invention, a head actuator is used during recording as the means for changing the track inclination angle, and the position of the recording head is moved during a recording period for one track. This is a characteristic feature.

The invention according to claim 3 provides a recording and reproducing apparatus for recording and reproducing data by forming inclined tracks divided into predetermined lengths on a magnetic tape. a guide drum; a band-shaped tape guide that is wound around the circumferential surface of the tape guide drum to regulate the edge position of the magnetic tape running on the drum circumferential surface; an inclined guide post for guiding; a band-shaped tape guide support device for supporting both ends of the band-shaped tape guide; a means for varying the inclination angle of the inclined guide post; and a variable inclination angle of the band-shaped tape guide support device. and means for changing the inclination angle of the track by varying the inclination angle of the inclined guide post and the band-shaped tape guide support device.

The invention according to claim 4 provides a recording and reproducing apparatus for recording and reproducing data by forming inclined tracks divided into predetermined lengths on a magnetic tape. a means for setting the recording time of the recording time; a means for varying the amount of recorded data per track in accordance with the amount of tape consumption that can be used for the set recording time; The tape is equipped with means for varying the track length by changing the track inclination angle in accordance with the amount of recorded data per recording, and means for changing the tape feeding speed in accordance with the change in the track inclination angle.
By changing the tape feed speed, the recording data amount per track and the track inclination angle are changed so that the data of the recording time is kept within the usable tape consumption and the track width is always constant. This is a characteristic feature.

The invention as set forth in claim 5 provides a recording/reproducing apparatus for reproducing a tape on which data is recorded by setting a plurality of track inclination angles on the magnetic tape. means for setting a recording time mode of the recorded data; means for setting a track inclination angle of a head trace during reproduction according to the recording time mode;
means for rotating the head in the azimuth angle direction; means for detecting the output level of the reproduction signal from the head; and determining the inclination angle of the recording track being reproduced from the change point of the reproduction signal output level and the rotation angle of the head at that time. The present invention is characterized by comprising a means for calculating.

[0026]

[Operation] In the first invention, by changing the track inclination angle, the track length can be changed, and the recording capacity per track can be arbitrarily set.

In the second invention, the track inclination angle in the first invention is varied by moving the head in the vertical direction using a head actuator, thereby making it possible to obtain an arbitrary track inclination angle.

In the third invention, a band-shaped tape guide is used, and a support device for the band-shaped tape guide and a means for varying the inclination angle of an inclined guide post that guides the magnetic tape are used. Since the track angle can be set arbitrarily, it becomes possible to perform recording and playback compatible with any tape format. In the fourth invention, the track width (
This makes it possible to keep the track pitch constant and prevent the S/N of the reproduced signal from deteriorating.

In the fifth invention, by rotating the head and observing changes in azimuth loss, it is possible to lower the band of the envelope detector of the reproduced signal and to increase the reliability of the detected value results.

[0030]

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

FIG. 1 is a diagram showing a circuit configuration of an embodiment of a recording/reproducing apparatus according to the present invention. The video signal to be recorded is sent to the signal processor 102 via the video signal input terminal 101, where unnecessary data is deleted and the data is compressed according to the recording data amount instruction signal from the mode setter 105.
After adding a check code to correct errors during reproduction, the data is encoded into recording data and sent to the head 109 via the recording amplifier 103. In this figure, only one of the opposing heads 109 is shown. The signal processor 102 also outputs the amount of recording data obtained as a result of determining the type of video signal and following the recording data amount instruction from the mode setting device 105 to the mode setting device 105. The mode setter 105 basically calculates the track inclination angle and tape feed amount per track that match the amount of recording data according to the rules described below. The mode setter 105 sends the calculated track inclination angle data to the track inclination angle controller 106 and the tape feed amount data to the tape speed controller 107. The tape speed controller 107 refers to the input tape feed amount data and controls the voltage applied to the motor 110, which is the rotary motive for the capstan 111, thereby controlling the tape speed. The structure of the track inclination angle controller 106 differs depending on the means for varying the track inclination angle. In FIG. 1, as an example, a head actuator is used to move the head 109 in the vertical direction.

In the above configuration, the mode setter 105
Then, the track inclination angle and tape feed amount per track are basically calculated according to the following rules. The amount of recorded data per field is M1
When the recording format is formed like track 1 in Figure 2, M2 = M1 per field.
/n When recording the amount of recording data, track 1
By forming a track 2 having a length L2=L1/n for the length L1, M2 can be recorded on one track with no excess or deficiency. As shown in FIG. 2, tracks of different lengths can be formed on a tape of the same width B by changing the inclination angle of the tracks.

Video full width B, track length L of track 1
1, inclination angle θ1, track length L2 of track 2, inclination angle θ2, L2 = L1 /n
(n: positive natural number)
, the following formula holds: θ2 = sin-1 (n・sin θ1) Also, the tape feed amount x2 per track of track 2 is calculated by subtracting the track pitch P2 from the track pitch P1 of track 1.
If it is the same as, the tape feed amount per track x1 of track 1 and the two track inclination angles θ1,
It can be determined from θ2 using the following formula.

[0034] x2 = (x1 ・sinθ1)/si
nθ2 Next, a means for varying the track inclination angle by vertically moving the head 109 using the head actuator 108 will be described.

Here, as a head actuator,
Here, we will discuss the case of using a moving coil in Figure 3.
This will be explained with reference to FIG. moving coil 2
04 is attached inside the rotating drum 201 as shown in FIG. The coil 210 is a leaf spring 203,
206, and the head 21 is attached to the tip of the bar on the side.
1 is attached, and the coil 210 contains permanent magnets 202 and 207 fixed at the center. When a current is applied to the conductor 208 on the outer periphery of the coil 210 to generate magnetic force, the magnetic force of the permanent magnets 202, 207 is repelled or attracted to move the coil 210 in the vertical direction against the drag of the leaf springs 203, 206. Conductor wire 20
The amount of vertical movement of this coil 210 is controlled by the strength of the current flowing through the coil 210, thereby controlling the position of the head 211. Conventionally, the track inclination angle was determined by the angle between the head rotating surface and the drum lead, and the speed of the tape and head, but if we keep these values constant and gradually move the head up and down the drum from the beginning of the track, The track inclination angle can also be changed by the vertical movement speed of the head.

FIG. 4 shows the state of control when forming a track with a length 1/2 of the reference track length, focusing on one of the opposing heads. The HSW 230 is a signal indicating switching between two opposing heads, and goes to "H" and "L" levels in response to head switching. The head we are currently focusing on is assumed to be in operation when it is at the "H" level. A control current 231 is a current flowing through the conducting wire 208, and the control current 231 is not changed as indicated by a dotted line 220 when the reference track length is formed. At this time, the height of the head from the bottom end of the tape changes, as shown by a dotted line 221, in accordance with the angle formed between the head rotation surface and the lead. Here, when the control current 231 is changed as shown by a solid line 222, the head 211 changes upward with time and moves at a speed combined with a component generated by the angle between the head rotation surface and the lead. As a result, the height of the head from the bottom end of the tape changes rapidly as shown by a solid line 223. If the rate of change in the head height from the bottom edge of the tape is made to be twice as long as it takes to form the reference track between times a and b, the time it takes for the head to scan the entire video width will be half the time it takes to form the reference track. On the other hand, considering that the relative speed of the tape head is generally determined predominantly by the rotational speed of the drum, the length of the track is 1/2 the length of the reference track.

Although it is not related to the track inclination angle operation, the recording tape trace time is between times a and b, and after that, the signal to the head is cut off between times b and e (it is not turned off between times c and e). (also good) Move the moving coil back to the original head height (
This is used to return the tape to the lower end of the tape. In this way, when the moving coil is moved largely, the interval between times ab and bc becomes shorter, that is, the interval between times bc becomes longer, and sudden control can be avoided when returning the moving coil to its position.

Since the track inclination angle is determined by the relative positional change between the head and the tape, it is of course possible to arbitrarily control it by the following method.

As shown in FIG. 5, 304 and 305 are vertical guide posts, 306 and 307 are movable inclined guide posts, and these posts guide the magnetic tape 303 to the tape guide drum 301 containing the rotating magnetic head 302. Determine the amount of wrapping. Reference numeral 308 denotes a tape guide made of a band-shaped winding member. This tape guide 308 forms an edge position regulating portion 309 shown in FIG.
Guide the lower edge of 03. 312 and 313 are movable support parts that support both ends of this tape guide 308. The movable support parts 312 and 313 are arranged to be rotatable with respect to the chassis. As shown in FIGS. 7 and 8, the movable support parts 312 and 313 are formed in a substantially pincushion shape, and a mounting hole is provided inside the movable support part 312 and 313 at a predetermined angle inclined from the central axis. Pillars 310, 31
1 are press-fitted at predetermined inclination angles φ1 and φ2, and are rotatable in the directions of arrows A1 and A2, respectively, by a drive source (not shown). Due to this rotation, the movable support parts 312, 31
3 is set to a predetermined inclination angle.

On the other hand, FIG. 9 shows a guide post assembly,
It consists of vertical guide posts 304, 305 and movable inclined guide posts 306, 307.

The movable inclined guide posts 306 and 307 shown in FIGS. 10 and 11 are replaced by the 312 and 313
The structure is similar to that in which the rotating columns 314 and 315 are press-fitted into the rotating columns 306 and 307 at predetermined inclination angles φ3 and φ4, and can be rotated in the directions of arrows B1 and B2, respectively, by the drive source 316 shown in FIG. It becomes. This rotation sets the movable inclined guide posts 306 and 307 to a predetermined inclination angle. With the above configuration, it is possible to set the inclination angle of the magnetic tape 303 and band-shaped tape guide 308 corresponding to any tape format.

FIGS. 12 to 15 show other embodiments of a mechanism for varying the inclination angle of the magnetic tape 303 and the band-shaped tape guide 308.

In FIGS. 12 and 13, 401, 40
2 is a movable inclined guide post, and the movable inclined guide posts 401 and 402 have rotating columns 403 and 404 arranged at a predetermined inclination angle φ5, as shown in FIGS. 14 and 15.
, φ6, and are rotatable in the directions of arrows C1 and C2, respectively, by a drive source (not shown). By this rotation, 401 and 402 are set to a predetermined inclination angle. The magnetic tape guides 411 and 412 and the band-shaped tape guide guides 413 and 414 are integrally constructed in these 401 and 402, and the inclination angle can be set in conjunction with each other.

FIG. 16 shows a configuration in which the guide posts described above are constructed as one assembly, and this assembly can be moved around the drum 301 during tape loading.

In FIG. 16, 501 is a winding device;
502 and 503 are guide post assemblies, including vertical guide posts 304 and 305, movable inclined guide posts 306 and 307, and movable support parts 312 and 313.
are planted respectively. Further, at 312, a winding means 501 for the band-shaped tape guide 308 is provided. With the above configuration, 312, 313, 304, 30
5, 306, and 307 can be loaded in conjunction with each other, the magnetic tape 303 and the band-shaped tape guide 308 are wound around the tape guide drum 301 almost simultaneously during tape loading. At this time 306
, 307, 312, and 313 are similarly configured to vary the inclination angle by the means described above.

FIG. 17 shows another embodiment of means for arbitrarily controlling the track inclination angle.

In FIG. 17, the tape guide drum 60
2 is mounted on a support stand 605 which is supported at both ends by pins 607 on the chassis 611 . A drum motor 606 is connected to the drum 602 . A stepping motor 6 is mounted on the bottom of the chassis 611.
10 is fixed, and the pulley 609 and the support base 6
05 is connected with a steel belt 608. When the motor 610 rotates stepwise in the direction of arrow D1, the belt 608 is wound around the pulley 609.
The drum 602 rotates in the direction of arrow E1 and has an inclination angle of φ7.
increases. On the other hand, when motor 610 rotates stepwise in the direction of arrow D2, belt 608 is let out from pulley 609, tape guide drum 602 rotates in the direction of arrow E2, and the inclination angle φ7 decreases. As described above, the inclination angle φ7 of the tape guide drum 602 is changed, and the head position is also changed from 603 to 604.
will be changed to Note that the above-described operation of the tape guide drum may be combined with the adjustment of the inclination angle of the movable inclined guide post and the movable support portion of the band-shaped tape guide.

Next, when the remaining tape capacity is insufficient for the recording time reserved in the standard mode, there is a method to prevent the error rate from deteriorating during playback even if the recording is switched to the long mode. The circuit configuration will be explained.

FIG. 18 is a diagram showing the circuit configuration of another embodiment of the recording/reproducing apparatus of the present invention. When the contents of an answering machine reservation are input to the answering machine reservation unit 702 via the reservation input terminal 701, the total time to be recorded is set at this point. on the other hand,
The tape remaining amount detection unit 703 detects, for example, the tape 704.
The remaining amount of tape is detected by optically reading the two reel thicknesses and calculating the ratio. Mode calculation unit 705
Using the total recording time output from the answering machine reservation section 702 and the remaining tape amount output from the remaining tape amount detection section 703 as input, first, the excess or deficiency of the tape amount when recording in the standard recording mode is calculated. Here, if the recording time is T, the remaining tape amount is Z, and the tape feeding speed in the standard mode is v0, the remaining tape amount will be insufficient for the recording time T if equation (1) is satisfied.

[0050] v0 ×T>Z
(1) If there is no shortage of tape, you can continue recording in the standard mode, but if there is a shortage, set a new mode. At this time, first, the tape feeding speed is determined according to the following equation (2).

vm=Z/T
(2) If the tape feeding speed to be set here is smaller than vm, there will be no shortage of tape, but for now, the following explanation will be based on vm. As shown in Fig. 19, if the full video width is B and the track pitch is P, then the tape feed amount per track is x0, xm in the standard mode and in the new mode.
are shown by equations (3) and (4), respectively.

[0052] sinθ0 =P/x0
(3) sinθm = P/xm

(4) Summarizing equations (3) and (4), the track inclination angle θm of the newly set mode is given by equation (5).

[0053] θm = sin-1((x0/xm)
-sin θ0 ) (5) Furthermore, the track length L0 in the standard mode can be estimated using equation (6), and the track length Lm in the new mode can be estimated using equation (7).

[0054] L0 = B/sinθ0
(6)
Lm =B/sinθm
(7) At this time, since the amount of data that can be recorded is proportional to the track length, the ratio Crm of the amount of recorded data in the new mode and in the standard mode is calculated by the formula (
8).

Crm=Lm/L0
(8)
The mode calculation unit 705 calculates the above equations (1) to (8), and outputs the tape feed amount xm per track to the tape feed speed controller via the output end 1 (706), and outputs the track inclination angle θm. is sent to the track inclination angle controller via output terminal 2 (707), and the ratio of recorded data amount Crm is sent to the signal processor via output terminal 3 (708). Here, the tape feed speed controller, track inclination angle controller, and signal processor are respectively the tape feed speed controller 10 of FIG.
7. Track tilt angle controller 106, signal processor 102
That's fine.

By doing this, if there is insufficient remaining tape during recording in the standard mode, the tape speed vm that will not cause the tape shortage is calculated, and thereby the tape per track is further reduced. - track feed amount xm, track inclination angle θm,
Calculate the recording data amount ratio (compression ratio) Crm, control the tape feed speed, track inclination angle, and data amount compression ratio, and record on the remaining amount of tape without excess or deficiency. be able to.

Furthermore, FIGS. 20 to 22 show circuit configurations when the mode is changed during recording, not when the recording time is known in advance at the start of recording, such as in answering machine recording.
This will be explained with reference to.

In FIG. 20, the recording time from the current time point onwards is input to the recording time setting section 902 via the input terminal 901. On the other hand, a tape remaining amount detection unit 903 detects the current remaining amount of the tape 904 . Mode calculation section 90
5, the recording time which is the output of the recording time setting section 902 and the remaining tape amount which is the output of the tape remaining amount detection section 903 are input, and 1 after the mode transition is performed according to equations (1) to (8).
Calculate the tape feed amount xm per track, track inclination angle θm, and recording data ratio Crm, and calculate the tape feed amount xm per track.
m is sent to the Δx limiter 906, the track inclination angle θm is sent to the Δθ limiter 907, and the recording data ratio Crm is sent to the ΔCr
Each is input to the restriction section 908 . Three restriction parts 9
Nos. 06, 907, and 908 limit the upper limit of the amount of change in each parameter per unit time, for example, per one head scanning time. The configurations of the three restriction parts are almost the same, so an example is shown in Figure 21.
Shown below.

In FIG. 21, data of the mode to which the final transition should be made is sent from the input terminal 920 to the mode calculation unit 905.
Input from The subtracter 921 calculates the difference between the final output of the delay element 922 and the data from the input terminal 920, and sends it to the saturator 923. saturator 923
Then, when the input data does not exceed the set limit value, the input value is output as is, and when the input value exceeds the limit value, the limit value is output and saturation processing is performed. The output of the saturator 923 and the output of the delay element 922 are added together by an adder 924, and the result is input to the delay element 922. For example, delay element 9
If the data of 22 is updated every head trace and the data is updated at the output end 925, the limiters 906 and 90
The output of 7,908 changes within a range that does not exceed a set limit value in one data update, and the mode is gradually changed during recording, and finally the data becomes the data of the desired mode.

FIG. 22 shows the transitional track pattern during the mode transition described above.

Track 1 with inclination angle θ0 before mode transition
The inclination angle changes by Δθ between adjacent tracks from 4 to track 4 with the inclination angle θm, and at this time, the tape feed amount per track is changed from x0 to xm so that a guard band is not formed at the beginning of the track. As can be seen from FIG. 22, when the mode transitions in the direction of shortening the track length, it is not necessarily necessary to limit the change in recorded data using the ΔCr limiter 908, and when the mode transition starts, the data amount is changed to the final transition mode. Also good.

Next, when reproducing a tape having a format recorded with a plurality of track inclination angles, a configuration that is an effective means for detecting the track inclination angle will be described.

FIG. 23 is a diagram showing the circuit configuration of another embodiment of the recording/reproducing apparatus of the present invention. In this explanation, FIG.
), the recording track is recorded with a lead that forms an inclination angle of θ1, and during playback, the head trace becomes θ2 (θ
The operation of detecting the track inclination angle when reproduction is to be performed with a lead having a trace inclination angle of 1>θ2) will be described.

In FIG. 23, first, during playback, input terminal 1
When the mode is set by the mode setting unit 1002 via 001, the track inclination angle is set accordingly and the set inclination angle information is sent to the loading unit 1003 and the track inclination angle calculation unit 1004. The loading unit 1003 determines the lead to be used according to the inclination angle information, places the tape 1005 on it, and performs a reproduction operation. Here, Figure 24
As shown in (a), the head trace 1022 advances across the recording track 1023. The head output at this time is as shown in FIG. 24(b), with a recording azimuth angle of 102
When the polarity of 4 and the reproduction azimuth angle 1025 are the same, it is large, and when the polarity is opposite, it is small, but the track inclination angle θ
The azimuth angle is always shifted by the difference θ21 between the trace inclination angle θ2 and the trace inclination angle θ2. Here, the head rotation control unit 1006 generates a control signal to rotate the head in the azimuth angle direction for each trace as shown in FIG. 24(c), and the head drive unit 1007 follows this control signal. The head is driven to rotate in the azimuth angle direction. Figure 24 (
Shown in d). The variation in the output envelope is determined by the degree of azimuth loss caused by changes in the azimuth angle. However, considering that the azimuth loss is small in the low signal band region and large in the high signal band region, and that envelope fluctuations due to space loss etc. are large in the high signal band region, the envelope detection unit 1008 uses the BPF (
Band Pass Filter) to limit the band,
Thereafter, the point at which the envelope of the reproduced signal is at its maximum is detected and output to the track inclination angle calculating section 1004. In the track inclination angle calculation section 1004, the head rotation control section 100
The rotation angle of the head when the envelope reaches the maximum is determined from the head rotation angle from 6 and the envelope maximum detection value from the envelope detection unit 1008. The rotation angle at this time is equal to the difference θ21 between the recording track inclination angle θ1 and the reproducing head trace inclination angle θ2. At this point, since the head trace angle θ2 and the head rotation angle θ21 are known, the recording track inclination angle θ1 can be calculated according to the following equation.

[0065] θ1 = θ2 + θ21 According to the above embodiment, by rotating the head in the azimuth angle direction when scanning the playback head, the playback is performed in order to know the change in the azimuth loss, regardless of the change in the playback output due to crossing the track. All you need to do is detect the envelope of the signal. In other words, if the rotational motion of the head is one head scanning period, the envelope detector only needs to have a lower band than the envelope detector that detects changes in head output due to track crossing, so it is possible to stably and accurately determine the track inclination angle. Detection becomes possible.

Next, regarding the head driving section 1007, FIG.
One configuration example will be explained with reference to 5.

In FIG. 25, a head 1040 is fixed to a head fixing plate 1041. Head fixing plate 104
One end of 1 is shaped like a rod, and the center is hollow. A fixing rod 1042 is inserted into this cavity, and the fixing rod 104
One end of 2 is fixed. A bimorph material 1043 is attached to one end of the sliding plate 1048 that contacts the rod-shaped portion of the head fixing plate 1041.
As the non-supporting end side of 43 moves in the AB direction by the control voltage applied from the control signal input terminal 1044, the sliding plate 1048 moves in the AB direction. The head fixing plate 1041 obtains rotational motion by the movement of this sliding plate 1048. The amount of rotation of the head is determined by the outer diameter of the rod-shaped portion of the head fixing plate 1041 and the amount of movement of the sliding plate 1048. Here, the head fixing plate 104 is adjusted so that the center of rotation is at the intersection of the rotation axis 1 (1046) and the rotation axis 2 (1047) in the figure, that is, the center of the head gap.
The shape of the head 1040 and the mounting position of the head 1040 must be determined. For example, the center point of the gap of the head 1040 may be placed on an extension of the center of the cavity of the head fixing plate 1041, that is, the axial center of the fixing rod 1042.

[0068]

[Effects of the Invention] As described above, according to the present invention, the data capacity for recording and playback per track can be set to any value, and recording and playback compatible with any tape format can be achieved. I'll take it if possible.

In addition, in order to lengthen the recording time, the tape feed speed is reduced and the track pitch can be kept constant by changing the track inclination angle, which reduces the error rate of the reproduced signal in the long-time mode. can be avoided.

Furthermore, when reproducing a tape in a format recorded with a plurality of track inclination angles, when the inclination angle of the recording track and the inclination angle of the head trace during playback are different, the inclination of the recording track It becomes possible to detect corners with high accuracy.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a circuit configuration of an embodiment of a recording/reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing the tape format of the embodiment of FIG. 1;

FIG. 3 is a schematic structural diagram of a moving coil that is an example of the head actuator shown in FIG. 1;

FIG. 4 is a diagram illustrating an operation when controlling a track inclination angle using the moving coil of FIG. 3;

FIG. 5 is a top view showing another embodiment of means for varying the track inclination angle.

FIG. 6 is a side view of FIG. 5.

7 is a cross-sectional view showing the configuration of the tape guide movable support section of FIG. 5. FIG.

FIG. 8 is a top view of FIG. 7.

FIG. 9 is an enlarged cross-sectional view of the guide post assembly of FIG. 5;

10 is a sectional view showing the configuration of the movable inclined guide post of FIG. 9. FIG.

FIG. 11 is a top view of FIG. 10.

FIG. 12 is a top view showing another embodiment of means for varying the track inclination angle.

FIG. 13 is a side view of FIG. 12.

14 is a cross-sectional view of the movable inclined guide post of FIG. 12 configured to allow the magnetic tape and the guide portion of the band-shaped tape guide to interlock with each other; FIG.

FIG. 15 is a top view of FIG. 14.

FIG. 16 is a top view showing another embodiment of means for varying the track inclination angle.

FIG. 17 is a side view showing another embodiment of means for varying the track inclination angle.

FIG. 18 is a diagram showing a circuit configuration of another embodiment of the recording/reproducing apparatus of the present invention.

FIG. 19 is a diagram showing the tape format of the embodiment of FIG. 18;

FIG. 20 is a diagram showing a circuit configuration of another embodiment of the recording/reproducing apparatus of the present invention.

FIG. 21 is a block diagram showing the configuration of a restriction section that is a component of the embodiment of FIG. 20;

FIG. 22 is a diagram showing the tape format of the embodiment of FIG. 20;

FIG. 23 is a diagram showing a circuit configuration of another embodiment of the recording/reproducing apparatus of the present invention.

FIG. 24 is an explanatory diagram of the operation of the embodiment of FIG. 23;

25 is a perspective view illustrating the configuration of a head driving section which is a component of the embodiment of FIG. 23. FIG.

[Figure 26] Conventional VT with multiple recording time modes
A configuration diagram of R.

[Figure 27] S/N of reproduced signal in digital VTR
FIG. 3 is a diagram showing the relationship between symbol error rate and symbol error rate.

FIG. 28 is a diagram showing input/output characteristics of error correction of a D-2 standard VTR.

FIG. 29 is a diagram illustrating calculation of the number of track crossings when the head scans at an incorrect inclination angle in a format in which tracks with different inclination angles exist.

[Explanation of symbols]

101...Video signal input terminal 102...Signal processor 104...Mode input terminal 105...Mode setting device 106...Track inclination angle controller 107...Tape feed speed controller 108...Head actuator 109...Head 110...Motor 111...capstan 204...Moving coil 304-307...Guide post 308... Band-shaped tape guide 312, 313...Movable support part 701... Reservation input terminal 702...Voice mail reservation department 703, 903...Tape remaining amount detection unit 704,904...tape 705,905...Mode calculation section 1001...Mode input terminal 1002...mode setting section 1003...Loading section 1004...Track inclination angle calculation unit 1006...Head rotation control section 1007...Head drive unit 1008...Envelope detection section

Claims (5)

[Claims] 1. In a recording/reproducing apparatus for recording and reproducing data by forming inclined tracks divided into predetermined lengths on a recording medium, means for setting a recording time mode of data to be recorded on the recording medium. means for changing and setting the amount of recorded data per track of input data according to the recording time mode; and means for changing the inclination angle of the track according to the recording time mode, 1. A recording/reproducing apparatus comprising: means for forming a track length corresponding to the length of the track; and means for changing the tape feeding speed in accordance with changes in the inclination angle of the track. 2. Recording and reproducing according to claim 1, wherein a head actuator is used during recording as the means for changing the track inclination angle, and the position of the recording head is moved during a recording period for one track. Device. 3. A recording and reproducing device for recording and reproducing data by forming inclined tracks divided into predetermined lengths on a magnetic tape, comprising: a rotating tape guide drum having a built-in magnetic head; a band-shaped tape guide that is wound around the circumferential surface of the guide drum to regulate the edge position of the magnetic tape running on the drum circumferential surface; and an inclined guide post that guides the magnetic tape to the circumferential surface of the tape guide drum. , comprising a band-shaped tape guide support device that supports both ends of the band-shaped tape guide, means for varying the inclination angle of the inclined guide post, and means for varying the inclination angle of the band-shaped tape guide support device. . A recording and reproducing apparatus, characterized in that the inclination angle of the track is changed by varying the inclination angle of the inclined guide post and the band-shaped tape guide support device. 4. A recording and reproducing apparatus that records and reproduces data by forming inclined tracks divided into predetermined lengths on a magnetic tape, in which a recording time of data to be recorded on the magnetic tape is set. When the usable tape consumption amount for a set recording time is determined, a means for varying the amount of recorded data per track in accordance with this, and a means for changing the amount of recorded data per track. Means for changing the inclination angle of the track to make the track length variable;
and means for changing the tape feed speed in accordance with the change in the track inclination angle, and by changing the tape feed speed, the data of the recording time is kept within the usable tape consumption amount, and A recording/reproducing device characterized in that the amount of recorded data per track and the track inclination angle are changed so that the track width is always constant. 5. A recording/reproducing apparatus for reproducing a tape on which data is recorded by setting a plurality of track inclination angles on a magnetic tape, wherein a recording time mode of data recorded on the magnetic tape is provided. means for setting a track inclination angle of a head trace during playback according to the recording time mode; means for rotating the head in an azimuth angle direction during playback; and a playback signal from the head. 1. A recording/reproducing apparatus comprising: means for detecting the output level of the reproduced signal; and means for calculating an inclination angle of a recording track being reproduced from a change point of the reproduced signal output level and a head rotation angle at that time.