JPH04368601A - Magnetic recording/reproducing device - Google Patents

Abstract

PURPOSE:To load either the front face and the rear face of a tape cassette by controlling the rotary direction of a rotary head drum in accordance with the front/rear detection result of a tape cassette and selecting the upper/lower step positions of a magnetic tape. CONSTITUTION:A cassette front/rear faces detection means 10 detects the front and the rear of the loaded tape cassette 9. When the front of the cassette 9 is an upper surface, a system control 11 rotates the rotary head drum 1 and recording/reproducing positions by the magnetic heads 2a-2d are controlled through a recording/reproducing position control part 13. Then, recording is executed on the upper step of the tape 3, and the travel direction of the tape 13 is reversed after the end of the tape. The rotary direction of the drum 1 is set to be as it is and recording/reproduction into the lower step of the tape 13 is executed. When the rear of the cassette 9 is the upper surface, the same operation is executed, and the loading direction of the cassette is not restricted, whereby operability is improved. Tape reciprocal recording/reproduction is executed without rewinding.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helical scan type magnetic recording and reproducing apparatus capable of recording and reproducing data on both sides of a tape cassette.

0002

2. Description of the Related Art Various types of VTRs have been proposed in the past, but the recording method of most VTRs is a so-called one-way recording method in which recording is performed in only one direction. In the case of this one-way recording method, it is necessary to rewind the recorded program in order to play it back, and when playing continuously for a long time, the playback may be interrupted by the time it takes to rewind when the end of the tape is reached, which is inconvenient. There is.

In order to overcome these drawbacks, a reciprocating recording VTR as shown in FIGS. 8 and 9 has been proposed in Japanese Patent Laid-Open No. 142702/1983. FIG. 8 shows the drum section of this VTR, and FIG. 9 shows the tape pattern. In the figure, 1 is a rotating head drum, and 2a, 2b, 2c, and 2d are magnetic heads, which are arranged on the rotating head drum 1 at equal angular intervals of 90 degrees. are formed with azimuth angles that are opposite to each other. 3 is a magnetic tape, 4 is an audio head, and 5 is a control head, and the control head 5 and the audio head 4 are formed in a switchable manner in two stages, upper and lower. Also, 6a, 6 in FIG.
b is a video track, 7a and 7b are audio tracks, 8a
, 8b indicate a control track.

[0004] The operation of the magnetic recording/reproducing apparatus constructed in this way will be explained below. In FIG. 8, during recording/reproduction, the magnetic tape 3 is helically attached to the outer periphery of the rotary head drum 1 over an angle θ slightly larger than 180°, and in this state, the magnetic tape 3 is attached in the forward direction (Fig. The magnetic heads 2a, 2b, 2c, and 2d are constantly rotated in the direction of arrow C. Now, when the magnetic tape 3 is running in the positive direction shown by arrow A during recording/reproduction, each of the magnetic heads 2a, 2b, 2
An electrical switching operation is performed alternately at 1/4 period of the head rotation period so that the recording/reproducing operation is performed when the magnetic tapes c and 2d are at the position of the latter half TA of the circumferential section with the magnetic tape 3. As a result, as shown in FIG. 9, on the magnetic tape 3, four magnetic heads 2a, 2b, 2c, and 2d each output one field of video signals in a helical shape at the upper half position with respect to the magnetic tape running direction. The audio signal and the control signal are recorded by the audio head 4 and control head 5 in the upper stage, respectively. FIG. 9 shows the recording pattern recorded by each head when the magnetic tape 3 runs in the forward direction, where 6a is a video track, 7a is an audio track, and 8a is a control track.

On the other hand, when the magnetic tape 3 reaches the end of the tape and is automatically reversed and runs in the opposite direction shown by arrow B, each of the rotating heads 2a, 2b, 2c, 2d moves to the first half TB of the circumferential section with the magnetic tape 3. An electrical switching operation is performed alternately so that recording/reproduction is performed when the recording/reproducing device is in the position. As a result, as shown in FIG. 9, the magnetic tape 3 has four magnetic heads 2a, 2 at the lower half position with respect to the tape running direction.
Helical video track 6 by b, 2c, 2d
b is formed, and the lower audio head 4 and control head 5 form an audio track 7b and a control track 8b.

[0006]

[Problems to be Solved by the Invention] As described above, conventional magnetic recording and reproducing devices can record and reproduce the tape back and forth with the tape cassette loaded, and there is no need to rewind the tape even when it reaches the end of the tape. Since the direction in which the tape cassette is loaded is specified, it is less troublesome than, for example, compact audio cassettes, which can be loaded on either side of the tape cassette and can be auto-reversed. There were some remaining problems.

The present invention was made in order to solve the above-mentioned problems, and provides a magnetic recording and reproducing device which can be loaded with either the front or back side of a tape cassette and which can perform auto-reverse operation. The purpose is to obtain.

[0008]

[Means for Solving the Problems] A magnetic recording and reproducing apparatus according to the present invention includes a detection means for detecting the front and back sides of a tape cassette, and a rotation direction of a rotary head drum based on a detection signal output from the detection means. The rotation control unit switches the recording/recording of the upper and lower stages of the magnetic tape based on the above detection signal.
The recording/reproduction position control section selects a reproduction position.

[0009]

[Function] In the magnetic recording/reproducing apparatus of the present invention, when recording/reproducing is performed with the tape cassette installed with the front surface facing upward, the rotational direction of the rotary head drum is constant and the tape running direction is changed to record/reproduce the tape cassette. A reproduction control section records/reproduces information on the upper and lower tiers that divide the magnetic tape into two in the width direction. In addition, when recording/playing is performed with the back side of the tape cassette facing up, the direction of rotation of the rotary head drum is reversed when recording/playing on the front side of the tape cassette, and the recording/playback is performed on the upper part of the magnetic tape. The tape running direction is reversed and the portion corresponding to the section is recorded/reproduced at the lower position of the magnetic tape. Alternatively, a portion corresponding to the recording/reproducing section at the lower stage of the magnetic tape is recorded/reproduced at the upper stage position of the magnetic tape.

0010

[Example] Example 1. As an embodiment of the present invention, an analog V tape is recorded/reproduced by attaching a magnetic tape in a helical manner over an angle of about 180 degrees to the outer periphery of a rotating head drum.
TR will be explained using FIGS. 1 to 4. 1 and 2, 1 is a rotating head drum, 2a, 2b, 2
Magnetic heads c and 2d are arranged on the rotating drum 1 at equal angular intervals of 90 degrees, and the magnetic heads 2a and 2c and the magnetic heads 2b and 2d are formed with azimuth angles opposite to each other. 3 is a magnetic tape, and 4 is an audio head, which can record/reproduce data at two locations on both ends of the magnetic tape 3 in the width direction. Reference numeral 5 denotes a control head that can record/reproduce data at two locations in the center of the magnetic tape 3 in the width direction. Further, in FIGS. 3 and 4, 6a and 6b are video tracks, 7a and 7b are audio tracks, and 8a and 8b are control tracks. Figure 1
Returning to the previous example, reference numeral 9 denotes a tape cassette capable of recording/reproducing on both sides, and a recess 9a for identifying the front and back sides of the tape cassette is formed only on one side. A switch 10 serves as a detection means for detecting the front and back sides of the tape cassette 9, and can detect the presence or absence of the recess 9a in the tape cassette 9. Reference numeral 11 denotes a system control for controlling the recording/reproducing state, into which the detection signal of the switch 10 and the REC/PB signal 31 are input. Reference numeral 12 denotes a rotation control section for starting/stopping and controlling forward/reverse rotation of the rotary head drum, into which the output of the system control 11, the FG signal 32, and the PG signal 33 are input. 13 is the magnetic head 2a, 2b, 2c, 2
In the recording/playback position control section that determines the operation timing of d, the PG signal 33, tape end signal 34, and recording/playback mode signal from the system control 11 are input, and the switch 14 is switched in response to these inputs to control the magnetic The operation timings of heads 2a, 2b, 2c, and 2d are determined. 15 is a recording amplifier, 16 is a reproduction amplifier, 1
7 is a switch for switching between recording and playback, which can be switched using the system control 11.

Next, the operation will be explained. In FIG. 2, during recording/reproduction, a magnetic tape 3 is connected to a rotary head drum 1.
The magnetic tape 3 is helically attached to the outer periphery of the tape over an angle θ slightly larger than 180°, and in this state, the magnetic tape 3 is driven to run in the forward direction (direction A in the figure) or in the reverse direction (direction B in the figure). be done. Also, the magnetic heads 2a, 2b, 2c, and 2d are operated in the direction of arrow C or in the direction of arrow C depending on the front and back sides of the tape cassette 9.
selectively rotated in the direction.

Now, when the magnetic tape 3 is running in the forward direction shown by arrow A (see FIG. 2) and recording/reproduction is performed with the front side of the tape cassette 9 facing upward, FIG.
This will be explained using FIG. 2. The tape cassette 9 is mounted in a predetermined position by a cassette mounting means (not shown). At this time, a switch 10 serving as a means for detecting the front and back sides of the tape cassette 9 detects that the front side of the tape cassette 9 is installed, and the signal is transmitted to the system control 11. Next, the system control 11 outputs a forward/reverse control signal for the rotary head drum 1 to the rotation control section 12 based on the above signal, and the rotation head drum 1 is rotated by the rotation control section 12 in the direction C in the figure (FIG. 2). I am made to do so. Further, the rotary head drum 1 receives the FG signal 3 by this rotation control section 12.
2. Constant rotation speed control is performed based on the PG signal 33. On the other hand, the magnetic heads 2a, 2b, 2c, and 2d alternate at 1/4 period of the head rotation period so that the recording/reproducing operation is performed when the magnetic heads 2a, 2b, 2c, and 2d are in the latter half TA position of the circumferential section with the magnetic tape 3 in FIG. An electrical switching operation is performed. To explain this situation with reference to FIG. 1, a PG signal 33 is input to the recording/reproducing position control section 13, and a head switching timing signal based on this PG signal 33 is generated internally. This signal sequentially controls the switches 14, and the magnetic head 2 is switched at 1/4 of the rotation period. Also,
The system control 11 controls the switch 17 to switch between recording and playback, and the recording amplifier 15 and the playback amplifier 16
The magnetic head 2 is selectively connected to. As a result, as shown in FIG. 3, the magnetic tape 3 has four magnetic heads 2a, 2b,
2c and 2d, each one field worth of video signals is sequentially recorded/reproduced in a helical manner. Furthermore, the upper audio head 4 and control head 5
As a result, an audio track 7a is formed at the upper end of the tape and a control track 8a is formed at the center of the tape. FIG. 3 thus shows the recording pattern recorded by each head when the magnetic tape 3 is running in the forward direction, where 6a is a video track, 7a is an audio track, and 8a is a control track.

Next, a description will be given of when the magnetic tape 3 reaches the end of the tape, is automatically reversed, and is run in the opposite direction shown by arrow B. This operation does not change the rotational state of the rotary head drum 1, but only changes the tape running direction. When the tape end is detected in FIGS. 1 and 2, the signal 34 is input to the recording/reproduction position control unit 12, and each magnetic head 2a, 2b, 2c, 2d in FIG. An electrical switching operation is performed alternately so that recording/reproduction is performed when the first half TB is located. In other words, inside the recording/playback position control section 13, the PG signal 3
3, a head switching timing signal that allows recording/reproducing at the position of the circumferential section TB is generated. This signal sequentially controls the switches 14, and the magnetic head 2 is switched at 1/4 of the rotation period. In addition, the system control 11 switches switch 17 to switch between recording and playback.
The magnetic head 2 is selectively connected to the recording amplifier 15 and the reproduction amplifier 16. As a result, as shown in FIG. 3, the magnetic tape 3 has four magnetic heads 2a, 2b, 2c, 2d located in the lower half of the magnetic tape running direction.
As a result, a helical video track 6b is formed, and the lower audio head 4 and control head 5 form an audio track 7b at the bottom end of the tape and a control track 8b at the center of the tape.

The above describes the recording/reproducing operation in a position where the front side of the tape cassette 9 is facing up.The above operation is considered a recording operation, and the recorded tape obtained by this recording operation is recorded in a position where the back side of the tape cassette 9 is facing upward. The case where the image is played back in the upper position will be explained. The recording pattern recorded with the tape cassette 9 placed on the front side is as shown in FIG. 3, and the recording pattern with this tape upside down is shown in FIG. In order to ensure compatibility between these recording patterns, it is necessary to reverse the tape running direction and the rotation direction of the rotary head drum 1, and to change the recording/playback position between the upper and lower tape stages. This can be easily understood from FIGS. 3 and 4.

Next, the operation of reproducing the back side of the tape cassette 9 will be explained. In FIGS. 1 and 2, the tape cassette 9 is mounted at a predetermined position by a cassette mounting means (not shown) so that recording/reproduction can be performed on the back side. At this time, switch 1 as means for detecting the front and back sides of tape cassette 9
0, it is detected that the back side of the tape cassette 9 has been installed, and the signal is transmitted to the system control 11. Next, the system control 11 outputs a forward/reverse control signal for the rotary head drum 1 to the rotation control unit 12 based on the above signal, and the rotation control unit 12 causes the rotary head drum 1 to rotate in a direction opposite to that during front side recording/reproduction. direction (arrow C). Further, the rotary head drum 1 is controlled to have a constant rotational speed by the rotation control section 12 based on the FG signal 32 and the PG signal 33. On the other hand, the magnetic tape 3 is run in the opposite direction shown by arrow B in FIG.
2b, 2c, 2d are the first half T of the circumferential section with the magnetic tape 3
An electrical switching operation is performed alternately at 1/4 period of the head rotation period so that the reproducing operation is performed when the head is at position B. As a result, the video track 6a at the bottom of the magnetic tape 3 in FIG. 4 is reproduced, and the audio track 7a and control track 8a are also reproduced by the audio head 4 and control head 5 at the bottom, respectively.

Next, a description will be given of when the magnetic tape 3 reaches the end of the tape, is automatically reversed, and is run in the positive direction shown by arrow A. This operation does not change the rotational state of the rotary head drum 1, but only changes the tape running direction, as in the case of recording/reproducing on the front side of the tape cassette 9. When the tape end is detected in FIGS. 1 and 2, the signal 34 is input to the recording/reproduction position control unit 12, and each magnetic head 2a, 2b, 2c, 2d in FIG. An electrical switching operation is performed alternately at 1/4 of the rotation period so that the reproducing operation is performed when the magnetic tape is at the position TA in the latter half of the rotation period, thereby reproducing the video track 6b on the upper stage of the magnetic tape 3 in FIG. Furthermore, the audio track 7b and the control track 8b are played back by the upper audio head 4 and control head 5, respectively.

The case where a previously recorded tape is played back from the back side of the tape cassette 9 has been described above, but the recording operation is only performed in the section of the above-mentioned playback operation, and the other operations are exactly the same. be.

Example 2. Further, in the above embodiment, four magnetic heads 2 are arranged on the rotary head drum 1, but this is because in the case of an analog VTR, continuity of the reproduction signal is required. In this case, the number of magnetic heads may be one or two. Specifically, an example in which two magnetic heads are disposed on the rotary head drum 1 will be explained.The configuration shown in FIG. 5 is as shown in Example 1. The reproduced output waveform in FIG. 6 is as shown in FIG. 6, while the reproduced output as shown in FIG.
In TR, it is easy to extend the time axis, so this is not a problem.

[0019]

As described above, according to the present invention, the tape can be recorded and played back and forth with the tape cassette loaded, and there is no need to rewind the tape even when the end of the tape is reached. Since the direction in which the cassette is loaded is not specified, it has the effect of providing very good operability.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a system of a magnetic recording and reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a magnetic recording/reproducing device according to an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a recording pattern diagram of the present invention.

FIG. 4 is a diagram showing another example of the recording pattern diagram of the present invention.

FIG. 5 is a plan view of a magnetic recording/reproducing device according to another embodiment of the invention.

FIG. 6 is a diagram showing a reproduction output waveform of the magnetic recording and reproducing apparatus of FIG. 2;

FIG. 7 is a diagram showing a reproduction output waveform of the magnetic recording and reproducing apparatus of FIG. 5;

FIG. 8 is a plan view showing a conventional magnetic recording/reproducing device.

FIG. 9 is a recording pattern diagram of a conventional magnetic recording/reproducing device.

[Explanation of symbols]

1 Rotating head drum 2 Magnetic head 3 Magnetic tape 9 Tape cassette 10 Magnetic tape front and back detection means 12 Rotation control section 13 Recording/playback position control section

Claims (1)

[Claims] 1. A helical scan type magnetic recording and reproducing device that divides a magnetic tape into two in the width direction and is capable of recording and reproducing the reciprocating motion of the tape, comprising a detection means for detecting the front and back sides of a tape cassette, and an output from the detection means. a rotation control section that switches the rotational direction of the rotary head drum based on the detected detection signal; and a recording/playback position control section that selects recording/playback positions on the upper and lower stages of the magnetic tape based on the detection signal. A magnetic recording/reproducing device characterized by: