JPH07161102A - Magnetic recording/reproducing apparatus - Google Patents

Abstract

PURPOSE:To obtain a magnetic recording/reproducing apparatus with which a reproduced image can be obtained in a noise-free state even if the image is reproduced at a high speed. CONSTITUTION:The rotation of a driving motor 1 is controlled by a control unit 47 so as to change the inclination angle of the center axis of a drum in accordance with the change of the running speed of a tape. FM signals are generated correspondingly with successive respective scanning traces one by one and supplied to an amplitude detector 41 to generate envelope signals. A plurality of sample values are picked up by a sample holding circuit 42 for each envelope signal in a period corresponding to each one of the successive respective scanning traces and the inclination angle of the center axis of the drum is changed under the control by the control unit 47 so as to have the plurality of the sample values equal to each other. After the inclination angle of the center axis of the drum is set in a proper state, tracking adjustment is executed by the control of the rotation phase of a capstan motor 52 corresponding to the rotation reference signal of a drum motor under the control by the control unit 47.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus.

[0002]

2. Description of the Related Art A magnetic tape wound around a part of the peripheral surface of a drum composed of an upper drum and a lower drum is run at a predetermined running speed, and a recording / reproducing operation is performed by using a rotary magnetic head. In using a video tape recorder (VTR), which is known as a typical example of the magnetic recording / reproducing apparatus, the normal reproduction is performed in which the recorded information is reproduced at the same magnetic tape running speed as that at the time of recording. (Normal playback)
In addition, trick play is also widely performed in which the magnetic tape is run at a running speed and running direction different from the running speed and running direction of the magnetic tape at the time of recording to perform a reproducing operation.
By the way, it is well known that the recording trace pattern (track pattern) recorded and formed on the magnetic tape corresponding to the rotation locus of the rotary magnetic head is different as the traveling speed of the magnetic tape is different. At the time of recording / reproducing (at the time of normal recording / reproducing), the rotation locus of the rotary magnetic head drawn on the magnetic tape by the rotary magnetic head,
The rotation locus of the rotary magnetic head drawn on the magnetic tape by the rotary magnetic head during trick play is, for example, as shown in FIG.
As shown in FIG.

Therefore, the signal level of the frequency-modulated wave signal of the reproduced signal reproduced during trick play greatly changes each time the rotary magnetic head crosses the recording mark, and the frequency-modulated wave signal of the reproduced signal in one vertical scanning period is changed. Looking at the envelope of the modulated wave signal, for example, as shown by the waveform of PBFM in FIG. 2, a large undulation occurs during one vertical scanning period, and the reproduced image at the time of trick play is the image. Only a poor quality reproduced image with a noise bar inside can be obtained. In order to solve the above-mentioned problems, it suffices that the rotation trace of the rotary magnetic head and the recording trace of the magnetic tape be made to coincide with each other. A rotary magnetic head is attached to the electro-mechanical conversion element, and the rotary magnetic head is displaced in the width direction of the recording trace by the electro-mechanical conversion element so that the rotary magnetic head can be traced to the recording trace of the magnetic tape. Is being done.

However, the electro-mechanical conversion element used as an actuator for controlling the rotational locus of the rotary magnetic head in the above-mentioned solution must be provided in a narrow space in the rotary drum. The electro-mechanical conversion element to be used is required to have a small shape and size, and as described above, the electro-mechanical conversion element having a small shape and size is difficult to give a large displacement to the rotary magnetic head. , The rotary magnetic head displaced by the electro-mechanical conversion element must be constructed so that the state of the head touch to the magnetic tape does not become defective even if the displacement occurs, but a small actuator that exhibits good operating characteristics is used. It is difficult to construct a VTR that performs excellent recording / reproducing operation in addition to noise at a very high speed. The scan can not be realized playback. Furthermore, since the electro-mechanical conversion element used as an actuator is expensive, it is difficult to adopt it in a consumer VTR. Therefore, as a solution to the above problems, a drum is used. When a reproducing operation is performed with the magnetic tape wound around a part of the peripheral surface of the tape at a traveling speed that is an integral multiple of the traveling speed during recording operation, the sliding contact surface of the magnetic tape is provided. An attempt was made to achieve noiseless playback at high speed by tilting the center axis of the rotating drum so that the recording traces formed on the magnetic tape and the rotational locus surface of the rotary magnetic head are aligned. Has been.

[0005]

By the way, conventionally, the reproducing operation is performed by setting the running speed of the magnetic tape wound around a part of the peripheral surface of the drum to be an integral multiple of the running speed of the magnetic tape at the time of recording. In this case, the drum at the time of inclining the central axis of the drum provided with the sliding contact surface of the magnetic tape so that the recording trace formed on the magnetic tape and the rotation locus surface of the rotary magnetic head coincide with each other. The method of setting the inclination angle of the central axis of the is to incline the central axis of the drum to the state of the inclination angle that is predetermined according to each reproduction speed, corresponding to the reproduction mode signal, In the above-mentioned conventional method, good operation can be expected in a normal state, but when reproducing a magnetic tape having a different inclination of the recording trace due to compatibility of the recording / reproducing apparatus, the recording trace formed on the magnetic tape is Rotating magnetic In order for the rotation locus surface of the de not a perfectly matched condition, sometimes noise playback screen occurs, it was determined that the solution.

[0006]

According to the present invention, there is provided a magnetic recording / reproducing apparatus in which a magnetic tape wound around a part of a peripheral surface of a drum is recorded / reproduced by using a rotary magnetic head. When the reproducing operation is performed while the magnetic tape is traveling at a traveling speed that is an integral multiple of the traveling speed of the magnetic tape, the central axis of the drum having the sliding contact surface of the magnetic tape is formed on the magnetic tape. Inclination drive means for inclining so that the recorded traces and the rotational locus surface of the rotary magnetic head are aligned with each other, and one rotational locus sequentially formed on the magnetic tape adjacently by the rotary magnetic head. 1 in the reproduction signal obtained in correspondence with
A means for obtaining a plurality of sampled values from a reproduction signal corresponding to the rotation locus of each book; a means for changing the inclination angle of the central axis of the drum in response to a change in the running speed of the magnetic tape; The plurality of sampled values obtained from the reproduction signals corresponding to the above-described rotation trajectories for each one after the inclination angle of the central axis of the are set to have a predetermined relative relationship. As described above, in the magnetic recording / reproducing apparatus including the means for changing the inclination angle of the central axis of the drum to an appropriate state, and the magnetic recording / reproducing apparatus described above,
When the reproducing operation is performed while the magnetic tape is traveling at a traveling speed that is an integral multiple of the traveling speed of the magnetic tape during the recording operation, the central axis of the drum having the sliding contact surface of the magnetic tape is set to the magnetic tape. Inclination drive means for inclining so that the formed recording trace and the rotation locus surface of the rotary magnetic head coincide with each other, and one each of which is sequentially formed on the magnetic tape by the rotary magnetic head so as to be adjacent to each other. Means for obtaining a plurality of sampled values from the reproduction signal corresponding to each of the above-described rotation trajectories in the reproduction signal obtained corresponding to the rotation trajectory, and corresponding to the change of the running speed of the magnetic tape. For changing the inclination angle of the central axis of the drum, and a plurality of reproduction signals corresponding to the above-mentioned respective rotational trajectories after the inclination angle of the central axis of the drum is changed. And a means for changing the inclination angle of the central axis of the drum to an appropriate state so that the sample value of is in a predetermined relative relationship, and the inclination angle of the central axis of the drum to an appropriate state. And a magnetic recording / reproducing apparatus including means for performing tracking adjustment by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor. The operation of changing the inclination angle of the drum central axis by the means for changing the inclination angle of the central axis of the drum and the tracking adjustment operation by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor are sequentially performed alternately. There is provided a magnetic recording / reproducing apparatus comprising:

[0007]

In response to the change in the running speed of the magnetic tape, the control unit controls the rotation of the drive motor to change the inclination angle of the central axis of the drum. A period corresponding to each one scanning locus by the rotary magnetic head by amplitude-detecting the reproduction frequency modulated wave signal reproduced from the magnetic tape corresponding to each one scanning locus by the rotary magnetic head. A signal indicative of the envelope of the reproduced frequency modulated wave signal therein is generated. A plurality of sampled values are extracted and held for each signal indicating the envelope of the reproduced frequency modulated wave signal during the period corresponding to each one scanning locus by the rotary magnetic head. The tilt angle of the central axis of the drum is changed under the control of the controller so that the plurality of sample values are equal. After the inclination angle of the central axis of the drum is set to an appropriate state, tracking adjustment is performed by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor under the control of the controller. Then, the operation of changing the inclination angle of the central axis of the drum and the tracking adjustment operation by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor are sequentially and alternately performed to record on the magnetic tape. The trace and the surface of the rotary locus of the rotary magnetic head are made to coincide with each other to realize noiseless reproduction during high-speed reproduction.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The specific contents of the magnetic recording / reproducing apparatus of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of a magnetic recording / reproducing apparatus of the present invention, FIG. 2 is a waveform diagram for explanation, FIG. 3 is a perspective view of a mechanical portion of the magnetic recording / reproducing apparatus of the present invention, FIGS. 6 is a block diagram showing a partial configuration of the magnetic recording / reproducing apparatus of the present invention, FIG.
Is a longitudinal sectional view showing a structural example of a drum structure that can be used in the magnetic recording / reproducing apparatus of the present invention, FIGS. 7 and 8 are views for explaining a tilted state of the drum, and FIGS. 9 and 10 are magnetic tape recordings. FIG. 4 is a plan view for explaining the relationship between traces and the rotation trajectory of the rotary magnetic head.

The magnetic recording / reproducing apparatus of the present invention is a magnetic recording / reproducing apparatus in which a rotating magnetic head is used for recording / reproducing operation on a magnetic tape wound around a part of the peripheral surface of a drum. When the reproducing operation is performed while the magnetic tape is traveling at a traveling speed that is an integral multiple of the traveling speed of the magnetic tape in, the central axis of the drum having the sliding contact surface of the magnetic tape is formed on the magnetic tape. First of all, since it belongs to the configuration form capable of realizing high-speed reproduction in a noiseless state by inclining so that the recorded trace and the rotational locus surface of the rotary magnetic head coincide with each other, 6 to 8, the sliding contact surface of the magnetic tape is provided during the reproducing operation performed by running the magnetic tape at a running speed that is an integral multiple of the running speed of the magnetic tape during the recording operation. And has a central axis of the drum, configuration examples of a mechanism portion so as to be inclined such that the state in which the rotation trajectory plane matches the recorded traces the rotary magnetic heads are formed on the magnetic tape will be described.

In FIGS. 6 and 7, DB is a drum base, DA is a drum structure DA including an upper drum Du and a lower drum Dd, and Ha and Hb are 180 degrees symmetrical to each other in the outer peripheral direction of the upper drum Du. Is a rotary magnetic head provided in the. The head holder 15 to which the rotary magnetic head Ha is attached and the head holder 14 to which the rotary magnetic head Hb is attached are mounted on the upper drum D by screws 16 and 17.
It is fixed to u. The upper drum Du is fixed to the upper drum fixing member 7 fixed to the rotary shaft 6 of the drum motor Md with screws 8 and 9. So
When the drum motor Md rotates at a predetermined rotation speed, the rotary magnetic heads Ha and Hb fixed to the upper drum Du are
It rotates integrally with the rotating shaft 6 rotatably supported by bearings 10 and 11 attached to the supporting member SA. Reference numeral 12 is a rotary transformer fixed to the upper drum fixing member 7, and 13 is a rotary transformer attached to the support member SA.

A drum motor Md is attached to the support member SA.
Of the drum motor Md is fixed to the support member 22 fixed to the rotary shaft 6 by a screw 25. , 24. The drum motor Md shown in the figure is provided with an armature winding 20a on its stator portion 20 and with a permanent magnet 21b on its rotor portion 21. Shown as one. The above-mentioned support member SA is provided in such a manner that the upper portion thereof is located in the inner space portion of the lower drum Dd, but the upper end portion 26 of the support member SA and the inner protruding edge portion of the fixed drum Dd. As shown in FIG. 6A, the rotation fulcrum 2 is provided in the direction of 90 degrees to 270 degrees of the drum structure DA with respect to 27.
8, 29 are provided.

Further, the support member SA has an upper end portion 26 thereof.
Of the fixed drum Dd is fitted to the upper surface side of the drum base DB and the support member SA.
The springs 30 and 31 mounted in the holes 90 and 91 provided on the upper surface side of the drum base DB are interposed between the lower surface side and the lower surface side of the drum base DB, and the holes provided on the lower surface side of the drum base DB. Spring 3 attached to 92, 93
4, 35 are provided between the supporting member SA and the cover 33 of the drum motor Md which is integrally connected and fixed. The lower drum Dd in the drum structure DA has a screw 94.
It is fixed to the drum base DB by.

Between the upper surface side of the drum base DB and the lower surface side of the support member SA, an annular cam member C for adjusting the inclination of the rotary shaft 6 which functions as a tilt adjusting means for the rotary shaft 6 is provided.
A (annular cam member CA) is provided. The cam contours formed on the upper surface of the above-mentioned annular cam member CA have cam followers 36, 3 protruding from the support member SA.
7, the annular cam member CA is connected via the rotary shaft 6 when the annular cam member CA is rotated by the driving force from the driving source (the motor 1 in FIG. 3). The upper drum Du, the support member SA, and the drum drive motor Md described above
The component consisting of is a center axis of the upper drum Du and the support member SA with the rotation fulcrums 28 and 29 as the center of rotation.
(The central axis of the rotary shaft 6) is at a predetermined angle, the lower drum Dd
The drum structure DA is inclined with respect to the central axis in the direction of 0 ° to 180 ° (the horizontal direction of the paper surface in FIGS. 6B and 7A and 7B). The cam contour of a predetermined shape in which the cam followers 36 and 37 projecting from the support member SA are brought into contact with the annular cam member CA for adjusting the inclination of the rotating shaft that functions as the inclination adjusting means of the rotating shaft 6. Is configured. Reference numeral 64 denotes a connecting portion, and an arcuate gear 39 (see the portion indicated by reference numeral 39 in FIG. 3) is provided at the tip end portion.

Power transmission from the drive source (motor 1 in FIG. 3) to the arcuate gear 39 is performed by the motor 1 →
The reduction gear 2 → the output shaft 3 → the pinion 38 → the arcuate gear 39 is routed through the path.
Is rotated in the guide groove 100 on the upper surface side of the drum base DB. The cam follower 3 protruding from the support member SA is formed on the cam contour of the annular cam member CA that performs a turning operation in the guide groove 100 on the upper surface side of the drum base DB.
Since the bearings 6 and 37 are in contact with each other, the bearing 10 attached to the support member SA when the annular cam member CA rotates,
The rotary shaft 6 rotatably supported by 11 is rotated by a predetermined angle from the central axis of the lower drum Dd in the direction of 0 ° -180 ° of the drum structure DA {(b) of FIG. 6 and FIG. 7).
(A) and (b) in the left-right direction of the paper surface}, whereby the upper drum Du, the support member SA, and the drum drive motor Md are integrally united by a predetermined angle respectively. Inclining the drum structure DA in the direction of 0 ° to 180 ° with respect to the center axis of the drum Dd (the horizontal direction of the paper in FIGS. 6B and 7A and 7B). You can

When the magnetic recording / reproducing apparatus is operating in the fast-forward reproducing mode, the contact between the cam contour of the annular cam member CA and the cam followers 36, 37 protruding from the supporting member SA causes The central axes of the upper drum Du and the supporting member SA (or the upper drum Du and the lower drum Dd) are as shown in FIG.
As shown in (a) (or the alternate long and short dash line in FIG. 8), the upper drum Du and the supporting member SA shown in FIG. 6 when the magnetic recording / reproducing apparatus is operating in the normal reproducing mode. (Or the state in which it is inclined to the right with respect to the position of the central axis of the upper drum Du and the lower drum Dd). Next, when the magnetic recording / reproducing apparatus using the drum structure DA illustrated in FIG. 6 is operated in, for example, the rewinding reproduction mode (FB), the magnetic recording / reproducing apparatus is projected on the support member SA. The center axes of the upper drum Du and the supporting member SA (or the upper drum Du and the lower drum Dd) are magnetically recorded by the contact between the cam followers 36 and 37 that are in contact with the cam contour of the annular cam member CA. When the reproducing apparatus is operating in the rewind reproducing mode, the magnetic recording / reproducing apparatus is operating in the normal reproducing mode as shown in FIG. 7B (or the dotted line in FIG. 8). In this case, it is inclined to the left with respect to the position of the central axis of the upper drum Du and the support member SA (or the upper drum Du and the lower drum Dd) shown in FIG.

Next, in FIG. 1, reference numeral 1 is a motor, which is used as a drive source for changing the inclination angle of the rotary shaft 6 which is the central axis of the drum structure DA. A pulse is generated from the rotary encoder RE as the motor 1 rotates. PS is a reference position detector that operates in association with the driving of the motor 1 described above. The motor 1, the rotary encoder RE, the reference position detector PS, etc. shown in FIG. 3 correspond to the motor 1, the rotary encoder RE, the reference position detector PS, etc. shown in FIG. In FIG. 3, 2 is a decelerator, 3 is an output shaft of the decelerator, and a pinion 38 is fixed to the output shaft 3. Pinion 38 described above
Are meshed with the arcuate gear 39.

The rotational force of the motor 1 driven in accordance with the control operation by the control unit 47 and the control circuit 50 in FIG. 1 is circled by the path of the motor 1 → the speed reducer 2 → the output shaft 3 → the pinion 38 → the arc gear 39. The rotation of the circular gear 39 transmitted to the circular gear 39 causes the circular cam member CA to rotate in the guide groove 100 on the upper surface side of the drum base DB by the connecting portion 64 as described above. Drum base DB
The cam contour formed on the annular cam member CA that performs the turning operation is rotated in the guide groove 100 on the upper surface side of the. Since the cam followers 36 and 37 projecting from the supporting member SA are in contact with the cam contour, the annular cam member C is formed.
Bearing 1 mounted on support member SA when A rotates
The rotary shaft 6 rotatably supported by 0 and 11 has a rotation angle of 0 ° -18 degrees of the drum structure DA with respect to the central axis of the lower drum Dd.
It is inclined in the direction of 0 degree {the horizontal direction of the paper surface in (b) of FIG. 6 and (a) and (b) of FIG. 7}.

In the magnetic recording / reproducing apparatus shown in FIGS. 3 and 6 and FIG. 7, the inclination angle of the rotary shaft 6 serving as the central axis of the drum is set to the annular cam member CA. The rotation amount of the cam contour described above corresponds to the rotation amount of the arc-shaped gear 39 described above. Therefore, the rotation shaft serving as the central axis of the drum described above. The inclination angle and the inclination direction of 6 can be determined by detecting the rotation amount and the rotation direction of the arcuate gear 39. PS shown in FIG. 3 is a position sensor, and the position sensor P
As S, a photo interrupter having a configuration in which a light shielding plate CP protruding from an arc-shaped gear 39 can move in an optical path between a light emitting element and a light receiving element which are arranged to face each other is used. can do. At the reference position of the rotary shaft 6 serving as the central axis of the drum, the light shielding plate CP projecting from the arcuate gear 39 is arranged so as to face the light emitting element and the light receiving element. The position of the light shielding plate CP which is projected from the arc-shaped gear 39 at the moment when the light of the light emitting element is received by the light receiving element is deviated from the optical path between the light receiving elements.

Therefore, the magnitude of the inclination angle and the inclination direction of the rotary shaft 6 which is the central axis of the drum are the arc-shaped gear 3 from the reference position of the rotary shaft 6 which is the central axis of the drum.
This can be known by knowing the amount of rotation of the light shielding plate CP that is provided so as to project on the beam guide 9. The rotation amount of the light-shielding plate CP protruding from the arc-shaped gear 39 is the output of the rotary encoder RE provided in the motor 1 used for rotating the arc-shaped gear 39. It can be known by the number of pulses. Therefore, the magnitude of the tilt angle and the tilt direction of the rotary shaft 6 serving as the central axis of the drum are used as the position sensor PS when the rotary shaft 6 serving as the central axis of the drum is at the reference position. It can be detected by counting the number of rotation pulses output from the rotary encoder RE by a counter preset to a predetermined value by the output signal of the photo interrupter.

In the block diagram of FIG. 1 showing the schematic structure of the magnetic recording / reproducing apparatus of the present invention, 40 is a reproduction signal (reproduction F
M signal) input terminal, 44 is head switch signal DFF
, 48 is an input terminal for the control pulse CTLP, and the reproduction F supplied to the input terminal 48 described above.
The M signal {see the signal PBFM in FIG. 2} is the amplitude detector 41.
2 and the amplitude detector 41 detects P
An envelope signal Pa of the reproduced FM signal PBFM as illustrated as a is output and supplied to the sample hold circuit 42. The sample and hold circuit 42 samples and holds the envelope signal Pa by the sampling signal Pb generated by the timing signal generator 45 (see the signal Pb in FIG. 2). In the timing signal generator 45 described above, the head switch signal DF supplied via the input terminal 44 is supplied.
The sampling signal Pb is generated based on F (see signal DFF in FIG. 2). The sampling signal Pb is an envelope signal corresponding to the reproduced FM signal reproduced from one recording trace. The signal portions near the head, the signal portions near the end, and the intermediate signal portion in Pa are generated at the time positions where they can be extracted.

The output signal from the sample and hold circuit 42 is individually analog-to-digital converted by the analog-to-digital converter 43, and then supplied to the control unit 47 including a microcomputer unit. A mode signal is also supplied to the control unit 47 via a mode signal input terminal 46. As described above, when the reproducing operation is performed by running the magnetic tape at a traveling speed faster than the traveling speed of the magnetic tape at the time of recording, the rotation locus of the rotating magnetic head during the reproducing operation and the magnetic Since the recording mark recorded on the tape is displaced as illustrated in FIG. 9, for example,
When adjacent recording traces are recorded by a rotary magnetic head having magnetic gaps having different azimuth angles, the portion surrounded by a solid line and the frame enclosed by a dotted line in FIG. Only the signal of the portion where the portion overlaps is reproduced, and thus the reproduced FM wave signal PBF in this case is reproduced.
M will be in the state illustrated in FIG.

Therefore, the reproduced FM wave signal PBFM described above is used.
Since the envelope signal Pa obtained by amplitude detection is as illustrated in FIG. 2, the envelope signal corresponding to one recording trace is near both ends and the center of one recording trace. The magnitudes of the signals sampled from the three parts near the part are not the same, but if the rotation track of the rotary magnetic head during the reproducing operation and the recording trace recorded on the magnetic tape are parallel, With respect to the envelope signal Pa obtained by amplitude-detecting the reproduced FM wave signal PBFM obtained in the state, the magnitudes of the signals sampled from three locations near both ends and near the central portion of one recording trace are the same. Therefore, with respect to the envelope signal Pa obtained by amplitude-detecting the reproduced FM wave signal PBFM, the magnitudes of the signals sampled from three locations near both ends and near the center of one recording mark are the same. By changing the tilt angle of the rotary shaft 6 which is the central axis of the drum, the direction of the rotation trace of the rotary magnetic head during the reproducing operation and the recording trace recorded on the magnetic tape can be matched. . By changing the inclination angle of the rotary shaft 6 which is the central axis of the drum as described above, the direction of the rotation track of the rotary magnetic head during the reproducing operation and the recording track recorded on the magnetic tape are aligned. Even in such a case, if the overlapping state of the two is a part as illustrated in FIG. 10, for example, the rotational phase of the capstan motor is phase-shifted to perform tracking so that the two can be superposed. It will be possible.

Therefore, in the magnetic recording / reproducing apparatus of the present invention,
A mode signal MOD indicating the traveling speed of the magnetic tape determined in correspondence with the reproduction operation mode is given to the control unit 47 via the input terminal 46, and the control circuit 50 causes the control unit 4 to operate.
The data C1 indicating the current inclination angle of the rotary shaft 6 which is the central axis of the drum is given to 7, and the control unit 47 further generates the signal Sg for determining the rotation direction of the motor 1 to the control circuit 50. Further, the control section 47 supplies the control circuit 50 with the stop target count value data D1 of the motor corresponding to the running speed of the magnetic tape according to the reproduction operation mode, and then supplies the start pulse St to the control circuit 50. To do. As a result, the control circuit 50 drives and controls the motor 1 in a predetermined rotation direction, and stops the motor 1 at the position determined by the motor stop target count value data D1. The motor 1 is rotated at a low speed so that it can be reliably stopped at the position determined by the stop target count value data D1 of the motor.

By the drive by the motor 1 described above, the inclination angle of the rotary shaft 6 serving as the central axis of the drum is set to an angle determined as being suitable for the running speed of the magnetic tape which is determined in correspondence with the reproducing operation mode. In this state, the reproduced FM wave signal PBFM reproduced by the rotary magnetic head is
When the difference in the magnitudes of the signals sampled from the three locations near both ends and near the central portion of one recording trace in the envelope signal Pa obtained by amplitude detection is a predetermined value or more, that is, the reproducing operation When the direction of the rotation track of the rotary magnetic head and the direction of the recording mark recorded on the magnetic tape are deviated from a predetermined value, the central axis of the drum can be corrected in such a direction that the deviation can be corrected. The motor 1 is driven so that the inclination angle of the rotating shaft 6 is changed. The reproducing FM reproduced by the rotary magnetic head for the correction operation described above.
Envelope signal P obtained by amplitude detection of wave signal PBFM
This is repeated until the difference in the magnitude of the signals sampled from the three points in the vicinity of both ends and the vicinity of the central portion of one recording trace in a becomes less than a predetermined value.

By the above-mentioned correction operation, the reproduction FM wave signal PBFM reproduced by the rotary magnetic head is amplitude-detected, and the envelope signal Pa is obtained. When the difference between the magnitudes of the extracted signals is less than or equal to a predetermined value, and when the sampled signals are small, that is, the rotation locus of the rotating magnetic head during the reproducing operation and the magnetic tape Even if the direction of the recorded trace matches, the overlapping state of the two is, for example, as shown in FIG.
In some cases, as illustrated in FIG. 2, the rotational phase of the capstan motor is then shifted to perform tracking so that the both are superposed. This makes it possible to control the rotation locus of the rotary magnetic head and the recording trace so that they substantially coincide with each other. The mode signal supplied to the control unit 47 through the mode signal input terminal 46 is information for setting the inclination angle of the rotating shaft 6 which is the center axis of the drum, which is already described. When the operation mode of the recording / reproducing apparatus is the normal recording mode, the recording / reproducing operation is performed with the inclination angle of the rotary shaft 6 serving as the central axis of the drum being fixed to the standard inclination.

In FIG. 1, reference numerals 49 and 50 denote control circuits. Of the two control circuits 49 and 50, the control circuit 49 is a control circuit for controlling the rotational phase of the capstan motor 52. A specific configuration example of is illustrated in the block diagram of FIG. The control circuit 49 has data D indicating the value for shifting the phase of the comparison reference signal from the control unit 47.
2, the head switch signal DFF from the input terminal 44 and the control signal CTLP from the input terminal 48 are also supplied to the control circuit 49. The motor drive signal MD2 is supplied from the control circuit 49 to the capstan motor 52, and the signal CAPFG generated by the frequency generator attached to the capstan motor 52 is supplied to the capstan motor 52 side. Is supplied to the control circuit 49.

The control circuit 50 of the two control circuits 49, 50 shown in FIG. 1 has an arc gear 39 for changing the inclination angle of the rotary shaft 6 which is the central axis of the drum.
The drive control operation of the motor 1 for rotationally driving is performed. Block 51 shown adjacent to the motor 1 in the figure
Is a rotary encoder RE provided in the motor 1,
And a sensor such as a photo interrupter used as the position sensor PS shown in FIG. The control operation for driving the motor 1 performed by the control circuit 50 is performed as follows. From the control unit 47 to the control circuit 50
Is supplied with the stop target count value data D1 of the motor and the start pulse St, and the control circuit 50 instructs the control section 47 to determine the tilt angle of the rotary shaft 6 which is the central axis of the drum. Data C1 indicating the current value is supplied. Further, the motor drive signal MD1 is supplied from the control circuit 50 to the motor 1, and the rotation pulse RPLS generated by the rotary encoder RE and the position sensor PS are supplied from the sensor 51 to the control circuit 50. The reference position signal STA generated in 1 is supplied.

In the control circuit 50 shown in FIG. 4, reference numeral 56 is a counter. In the counter 56, the reference position signal STA generated by the position sensor PS in the sensor 51 is supplied to the preset terminal. At that time, the numerical value set in the register 57 is preset, and the sensor 5
The rotation pulse RPLS generated by the rotary encoder RE in No. 1 is used as the counted pulse to perform the counting operation, and the counted value C1, that is, the current value of the inclination angle of the rotation shaft 6 which is the center axis of the drum is given to the comparator 53. It is also supplied to the control unit 47. As described above, the reproduction F reproduced from one recording mark by the sampling pulse Pb.
The signal sampled from the signal portion near the head (end) in the envelope signal Pa corresponding to the M signal and the signal sampled from the vicinity of the center are sequentially output from the sample hold circuit 42, which is analog. The control unit 47, to which the analog-to-digital converted data is given by the digital converter 43, calculates the difference between the data given from the analog-digital converter 43, and based on the value of the difference between the data. The motor stop target count value data D1 corresponding to the target value of the inclination angle of the rotary shaft 6 which is the central axis of the drum is determined and given to the control circuit 50.

In the control unit 47, the value of the difference between the data by the signals newly sampled by the sample hold circuit 42 is the difference between the data by the signals sampled one sampling period before. When the value becomes larger than the value, the tilt angle of the rotary shaft 6 serving as the drum central axis is set in a direction opposite to the direction in which the tilt angle of the rotary shaft 6 serving as the drum central axis was changed last time. A signal Sg that determines the rotation direction of the motor 1 to be changed by a predetermined amount is generated and supplied to the control circuit 50. As described above, when the start pulse St is generated in the control unit 47 and is supplied to the control circuit 50 from the control unit 47, the set reset flip-flop 54 of the control circuit 50 is set by the start pulse St described above. . Further, when the control unit 47 generates a signal Sg that determines the rotation direction of the motor 1, and the control unit 47 gives it to the control circuit 50, the signal Sg causes the set / reset flip-flop 55 of the control circuit 50 to operate. Set.

When the set / reset flip-flop 54 in the control circuit 50 is set, the high-level signal output from the Q output terminal of the set / reset flip-flop 54 is switched SW.
Turn 1 on. When the switch SW1 is turned on, the positive power source 59 is connected to the motor drive circuit 61, so that the motor drive circuit 61 supplies the motor drive signal MD1 to the motor 1 to rotate the motor 1 in the normal direction. To be done. The forward rotation of the motor 1 causes the arc-shaped gear 39
Is rotationally driven to change the inclination angle of the rotary shaft 6 which is the central axis of the drum. Further, when the set / reset flip-flop 55 in the control circuit 50 is set, the high level signal output from the Q output terminal thereof turns on the switch SW3. When the switch SW3 is turned on, the negative power source 60 causes the motor drive circuit 61 to operate.
The motor drive circuit 61 supplies the motor 1 with a motor drive signal MD1 that causes the motor 1 to rotate in the reverse direction. The arcuate gear 39 is rotationally driven by the reverse rotation of the motor 1, and the inclination angle of the rotary shaft 6 that is the center axis of the drum is changed.

By the normal rotation operation or the reverse rotation operation of the motor 1 as described above, the target position in the direction in which the inclination angle of the rotating shaft 6 which is the center axis of the drum increases or the target in the direction in which the inclination angle decreases becomes smaller. As the position changes, the count value C1 of the counter 56, which indicates the current value of the inclination angle of the rotary shaft 6 serving as the central axis of the drum, changes.
Then, the above-mentioned counter 5 supplied to the comparator 53
When the count value C1 of 6 and the stop target count value data D1 of the motor supplied from the control unit 47 to the comparator 53 match, the set reset flip-flop 55 is caused by the match pulse output from the comparator 53. Is reset and a high-level output signal is output from the NOR circuit 58, which turns on SW2. Switch SW2
When is turned on, the ground potential is applied to the input side of the motor drive circuit 61, the driving operation of the motor 1 by the motor drive circuit 61 is stopped, and the inclination angle of the rotary shaft 6 serving as the central axis of the drum is changed. The target position set by the control unit 47 is held. As described above, in the magnetic recording / reproducing apparatus of the present invention, the tilt angle of the rotary shaft 6 serving as the central axis of the drum is repeatedly changed by the control operation by the control unit 47 and the control circuit 50 as described above. The rotation locus of the rotary magnetic head and the recording trace are controlled so as to substantially coincide with each other.

As described above, the reproduced FM wave signal PBFM
Of the envelope signal Pa obtained by amplitude detection of
The reproduction operation is performed by changing the tilt angle of the rotary shaft 6 which is the central axis of the drum so that the magnitudes of the signals sampled from the three locations near both ends and the central portion of the recording mark of the book are the same. Even when the direction of the rotation track of the rotary magnetic head at the time and the direction of the recording trace recorded on the magnetic tape can be made to coincide with each other, the overlapping state of the two is in the state as illustrated in FIG. 10, for example. In this case, the reproduced FM wave signal PBFM is reproduced with a low signal level. In such a case, the rotational phase of the capstan motor is phase-shifted to perform tracking, so that the both are properly superposed and a high-level reproduced FM wave signal PBFM is obtained.

Therefore, in the magnetic recording / reproducing apparatus of the present invention, the signal obtained by dividing the output signal of the capstan frequency generator and the periodic signal related to the vertical synchronizing signal of the input video signal are used so that the reproduction output becomes maximum. Is controlled to control the rotational phase of the capstan motor by a signal obtained by phase comparison with a signal obtained by delaying. The relationship between the recording trace to be newly recorded and the control pulse is recorded on the magnetic tape at a time point immediately before the start of the recording operation by controlling so as to maintain the state immediately before the start of the recording operation. The above problem is solved by making the relationship between the recorded trace and the control pulse the same, and the control operation described above is performed by the control unit 47 and the control circuit 49.
Performed by and.

FIG. 5 showing a concrete example of the configuration of the control circuit 49.
, The head switch signal DFF, which repeats the high level state and the low level state every one field period in synchronization with the input video signal, is supplied to the subtraction counter 65 and the monostable multivibrator 70. Therefore, the subtraction counter 65 is supplied with data D2 indicating a value for shifting the phase of the comparison reference signal from the control section 47, and also with a clock signal from the AND circuit 63. The control signal CTLP is given as a signal to be counted to the programmable frequency divider 68 whose frequency division ratio is changed by the mode signal. The subtraction counter 65 is preset with data D2 indicating a value for shifting the phase of the comparison reference signal when the head switch signal DFF is applied to its preset terminal. The numerical value preset in the subtraction counter 65 is subtracted by the clock pulse oscillated by the oscillator 62 being supplied through the AND circuit 63.

When the value of the subtraction counter 65 becomes zero, a high level signal is output from the zero detector 66 and is supplied to the phase comparator 67 and the monostable multivibrator 71. To be done. By applying the head switch signal DFF to the preset terminal,
When the subtraction counter 65 is preset, the output signal from the monostable multivibrator 70 triggered by the head switch signal DFF is supplied to the set terminal to set the flip-flop 69, and its Q output. When the terminal becomes high level,
The clock pulse oscillated by the oscillator 62 is supplied to the subtraction counter 65 via the AND circuit 63, and the subtraction counter 65 starts counting.

The flip-flop 69 outputs the output signal of the monostable multivibrator 71 triggered by the high level signal output from the zero detector 66 when the value of the subtraction counter 65 becomes zero. When the clock signal is supplied to the reset terminal, it is reset and the Q output terminal of the flip-flop 69 becomes low level, so that the clock pulse is not supplied from the oscillator 62 to the subtraction counter 65 via the AND circuit 63. That is, the AND circuit 63, to which the gate signal is applied from the flip-flop 69 as described above, outputs zero or more high level outputs at least twice during one cycle of the head switch signal DFF. In order to prevent the output from 66, the operation of limiting the input of the clock pulse supplied from the oscillator 62 to the subtraction counter 65 is performed.

The data D2 indicating the value for shifting the phase of the comparison reference signal supplied from the control unit 47 to the control circuit 49 is
Since the time from the time point of the head switch signal DFF to the time point when the high-level signal is output from the zero detector 66 is determined, the data D2 indicating the value for shifting the phase of the comparison reference signal is set as the rotation target phase. The rotation phase of the stun motor changes according to a change in data D2 indicating a value for shifting the comparison reference signal. The phase comparator 67 described above
Error signal generated by the frequency generator and the signal C generated by the frequency generator
The output signal from the subtracter 73, to which the signal obtained by converting the APFG into the voltage by the frequency-voltage converter 72 is applied, is phase-compensated in the phase compensating circuit 74, and the signal is capped by the motor driving circuit 75 as the motor driving signal MD2. It is given to the stun motor 52. Then, since the change of the rotation phase of the capstan motor changes the rotation locus of the rotary magnetic head in the width direction of the recording mark, the tracking control can be performed by changing the rotation phase of the capstan motor as described above. You can do it.

[0038]

As is clear from the above description, in the magnetic recording / reproducing apparatus of the present invention, the control unit controls the rotation of the drive motor in response to the change in the running speed of the magnetic tape. , Change the inclination angle of the central axis of the drum,
A period corresponding to each one scanning locus by the rotary magnetic head by amplitude-detecting the reproduction frequency modulated wave signal reproduced from the magnetic tape corresponding to each one scanning locus by the rotary magnetic head. A signal indicating the envelope of the reproduced frequency modulated wave signal is generated, and for each signal indicating the envelope of the reproduced frequency modulated wave signal during the period corresponding to each one scanning locus by the rotary magnetic head described above. , A plurality of sample values are extracted and held, and the tilt angle of the central axis of the drum is changed under the control of the control unit so that the plurality of sample values are equal.
After the inclination angle of the center axis of the drum is set to an appropriate state, tracking adjustment is performed by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor under the control of the control unit. The change operation of the inclination angle of the central axis and the tracking adjustment operation by controlling the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor are alternately performed in order, and the recording mark formed on the magnetic tape and the rotating magnetic head Since the magnetic recording and reproducing device of the present invention can perform good inclination correction even on the compatible magnetic tape because the rotational locus surface is in a state of being in agreement with each other, noiseless reproduction during high-speed reproduction is possible. Can be realized,
Further, even if an off-track occurs due to the tilt correction, good tilt correction can be performed without malfunction, and high-speed reproduction in a noiseless state can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a magnetic recording / reproducing apparatus of the present invention.

FIG. 2 is a waveform diagram for explanation.

FIG. 3 is a perspective view of a mechanical portion of the magnetic recording / reproducing apparatus of the present invention.

FIG. 4 is a block diagram showing a partial configuration of the magnetic recording / reproducing apparatus of the present invention.

FIG. 5 is a block diagram showing a partial configuration mode of the magnetic recording / reproducing apparatus of the present invention.

FIG. 6 is a vertical cross-sectional view showing a configuration example of a drum structure that can be used in the magnetic recording / reproducing apparatus of the present invention.

FIG. 7 is a diagram for explaining a tilted state of a drum.

FIG. 8 is a diagram for explaining a tilted state of a drum.

FIG. 9 is a plan view for explaining the relationship between the recording trace of the magnetic tape and the rotation trajectory of the rotary magnetic head.

FIG. 10 is a plan view for explaining the relationship between the recording trace of the magnetic tape and the rotation trajectory of the rotary magnetic head.

[Explanation of symbols]

DA ... Drum structure consisting of upper drum Du and lower drum Dd, PS ... Reference position detector (position sensor), CP ... Shade plate, DB ... Drum base, Ha, Hb ... Rotating magnetic head, SA ... Support member, Md ... drum motor, CA ... annular cam member, RE ... rotary encoder, 1 ... motor,
2 ... Reduction gear, 3 ... Output shaft, 6 ... Rotation shaft, 28, 29 ... Rotation fulcrum, 36, 37 ... Cam follower, 38 ... Pinion, 3
9 ... Arc gear, 42 ... Sample and hold circuit, 43 ...
Analog-digital converter, 45 ... Timing signal generator, 47 ... Control section, 49, 50 ... Control circuit, 52 ... Capstan motor, 53 ... Comparator, 54, 55 ... Set / reset flip-flop, 56 ... Counter, 57 ... Numeric unit, 58 ... NOR circuit, 61 ... Motor drive circuit, 62 ... Oscillator, 63 ... AND circuit, 64 ... Connection part, 65 ... Subtraction counter, 66 ... Zero detector, 67 ... Phase comparator, 68 ... Programmable Frequency divider, 69 ... Flip-flop, 70,
71 ... Monostable multivibrator, 73 ... Subtractor, 74
... Phase compensation circuit, 75 ... Motor drive circuit, 100 ... Guide groove,

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[Procedure amendment]

[Submission date] January 18, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

Therefore, in the magnetic recording / reproducing apparatus of the present invention,
A mode signal MOD indicating the traveling speed of the magnetic tape determined in correspondence with the reproduction operation mode is given to the control unit 47 via the input terminal 46, and the control circuit 50 causes the control unit 4 to operate.
Data C1 indicating the current tilt angle of the rotary shaft 6 which is the central axis of the drum is given to 7, and the control unit 47 further generates a signal Sg for rotating the motor 1 in the reverse direction to the control circuit 50. Further, the control section 47 supplies the stop target count value data D1 of the motor corresponding to the running speed of the magnetic tape according to the reproducing operation mode to the control circuit 50.
Signal St that causes the motor 1 to rotate in the forward direction after being applied to
Is supplied to the control circuit 50. As a result, the control circuit 50 drives and controls the motor 1 in a predetermined rotation direction, and stops the motor 1 at the position determined by the motor stop target count value data D1. The motor 1 is rotated at a low speed so that it can be reliably stopped at the position determined by the stop target count value data D1 of the motor.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

The control circuit 50 of the two control circuits 49, 50 shown in FIG. 1 has an arc gear 39 for changing the inclination angle of the rotary shaft 6 which is the central axis of the drum.
The drive control operation of the motor 1 for rotationally driving is performed. Block 51 shown adjacent to the motor 1 in the figure
Is a rotary encoder RE provided in the motor 1,
And a sensor such as a photo interrupter used as the position sensor PS shown in FIG. The control operation for driving the motor 1 performed by the control circuit 50 is performed as follows. From the control unit 47 to the control circuit 50
, The stop target count value data D1 of the motor and the signal St for rotating the motor 1 in the forward rotation direction are supplied,
Further, the control circuit 50 supplies the control unit 47 with data C1 indicating the current value of the inclination angle of the rotary shaft 6 which is the central axis of the drum. Further, a motor drive signal MD1 is supplied from the control circuit 50 to the motor 1,
The sensor 51 supplies the control circuit 50 with the rotation pulse RPLS generated by the rotary encoder RE and the reference position signal STA generated by the position sensor PS.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

In the control unit 47, the value of the difference between the data by the signals newly sampled by the sample hold circuit 42 is the difference between the data by the signals sampled one sampling period before. When the value becomes larger than the value, the tilt angle of the rotary shaft 6 serving as the drum central axis is set in a direction opposite to the direction in which the tilt angle of the rotary shaft 6 serving as the drum central axis was changed last time. A signal motor 1 that determines the rotation direction of the motor 1 to be changed by a predetermined amount
Generates a signal Sg for rotating in the reverse direction and supplies it to the control circuit 50. As described above, when the control unit 47 generates the signal St for rotating the motor 1 in the normal rotation direction and gives it to the control circuit 50, the motor 1 is rotated in the normal rotation direction. Signal St
This sets the set / reset flip-flop 54 of the control circuit 50. Further, when the control unit 47 generates the signal Sg for rotating the signal motor 1 that determines the rotation direction of the motor 1 in the reverse rotation direction and supplies the signal Sg to the control circuit 50 from the control unit 47, the signal motor 1 described above is activated. The set / reset flip-flop 55 of the control circuit 50 is set by the signal Sg for rotating in the reverse direction.

Claims (3)

[Claims] 1. In a magnetic recording / reproducing apparatus in which a rotating magnetic head is used to perform a recording / reproducing operation on a magnetic tape wound around a part of the peripheral surface of a drum, the running speed of the magnetic tape during the recording operation. When a reproducing operation is performed while the magnetic tape is running at a running speed that is an integral multiple of the number of times, the center axis of the drum equipped with the sliding surface of the magnetic tape is Reproduction obtained in correspondence with tilt drive means for inclining the head so that the surface of the head's rotation locus coincides with each one, and one rotation locus sequentially formed on the magnetic tape adjacently by the rotary magnetic head. Means for obtaining a plurality of sampled values from the reproduced signal corresponding to each of the above-described rotation trajectories in the signal, and the inclination angle of the central axis of the drum corresponding to the change of the running speed of the magnetic tape. Strange And a plurality of sampled values obtained from the reproduction signal corresponding to each of the above-described rotation trajectories after the inclination angle of the central axis of the drum is changed. So that it has a relative relationship
A magnetic recording / reproducing apparatus comprising means for changing the inclination angle of the central axis of the drum to an appropriate state. 2. A running speed of a magnetic tape during a recording operation in a magnetic recording / reproducing apparatus in which a rotating magnetic head is used to perform a recording / reproducing operation on a magnetic tape wound around a part of a peripheral surface of a drum. When a reproducing operation is performed while the magnetic tape is running at a running speed that is an integral multiple of the number of times, the center axis of the drum equipped with the sliding surface of the magnetic tape is Reproduction obtained in correspondence with tilt drive means for inclining the head so that the surface of the head's rotation locus coincides with each one, and one rotation locus sequentially formed on the magnetic tape adjacently by the rotary magnetic head. Means for obtaining a plurality of sampled values from the reproduced signal corresponding to each of the above-described rotation trajectories in the signal, and the inclination angle of the central axis of the drum corresponding to the change of the running speed of the magnetic tape. Strange And a plurality of sampled values obtained from the reproduction signal corresponding to each of the above-described rotation trajectories after the inclination angle of the central axis of the drum is changed. So that it has a relative relationship
The means for changing the inclination angle of the central axis of the drum to a proper state, and the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor after the inclination angle of the central axis of the drum is set to an appropriate state. And a means for performing tracking adjustment under the control of 1. 3. In a magnetic recording / reproducing apparatus in which a rotating magnetic head is used to perform a recording / reproducing operation on a magnetic tape wound around a part of the peripheral surface of a drum, the running speed of the magnetic tape during the recording operation. When a reproducing operation is performed while the magnetic tape is running at a running speed that is an integral multiple of the number of times, the center axis of the drum equipped with the sliding surface of the magnetic tape is Reproduction obtained in correspondence with tilt drive means for inclining the head so that the surface of the head's rotation locus coincides with each one, and one rotation locus sequentially formed on the magnetic tape adjacently by the rotary magnetic head. Means for obtaining a plurality of sampled values from the reproduced signal corresponding to each of the above-described rotation trajectories in the signal, and the inclination angle of the central axis of the drum corresponding to the change of the running speed of the magnetic tape. Strange And a plurality of sampled values obtained from the reproduction signal corresponding to each of the above-described rotation trajectories after the inclination angle of the central axis of the drum is changed. So that it has a relative relationship
The means for changing the inclination angle of the central axis of the drum to a proper state, and the rotation phase of the capstan motor with respect to the rotation reference signal of the drum motor after the inclination angle of the central axis of the drum is set to an appropriate state. Means for performing tracking adjustment by controlling the tilt angle of the central axis of the drum by the means for changing the tilt angle of the central axis of the drum, and the capstan motor for the rotation reference signal of the drum motor. A magnetic recording / reproducing apparatus comprising: means for enabling tracking adjustment operation by control of rotational phase to be sequentially and alternately performed.