JP2614852B2 - Helical scan type recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus that records or reproduces a digital signal by a helical scan method using a rotary head.

[Summary of the Invention]

The present invention relates to a recording / reproducing apparatus that records or reproduces a digital signal by a helical scan method using a rotary head, reproduces the recorded digital signal after recording a predetermined digital signal, and detects an error in the recorded digital signal. The recording medium is skipped for one track only when the digital signal is correctly recorded, and the correct signal can be recorded without changing the arrangement order of the recording tracks.

[Conventional technology]

Conventionally, information signals such as audio signals are converted to PCM (Pulse Cod
A helical scan type magnetic recording / reproducing apparatus using a rotary head that converts a signal into an e-modulation signal and records / reproduces the information as digital information has been put to practical use.

By the way, when an information signal such as an audio signal is converted into a PCM signal and is recorded on a magnetic tape, a PCM signal is usually used.
An error correction code is attached to each word of the signal, and processing such as interleaving is performed in units of several words. Therefore, a memory capable of recording several words of a PCM signal as one block is used, and data processing is performed in which the PCM signals to be recorded in the memory are temporarily stored and sequentially read.

To solve the problem caused by continuous feeding of the magnetic tape, the applicant of the present application has proposed a technique disclosed in Japanese Patent Application Laid-Open No.
No. 512 proposes a magnetic tape feeding system in which the magnetic tape is intermittently fed one track at a time to record and reproduce a PCM signal.

According to the magnetic tape feeding method as disclosed in the above publication, the analog control circuit is unnecessary because the analog servo which is required by the conventional device for continuously feeding the magnetic tape and recording and reproducing the PCM signal is not required, Most of the electronic circuits for controlling the feeding of the magnetic tape in addition to processing the information signals to be recorded and reproduced can be constituted by digital ICs, which facilitates the construction of the electronic circuits. Furthermore, CTL is used for magnetic tape feed control.
Since a signal is not particularly required, there is also an advantage that the recording / reproducing apparatus can be made compact.

[Problems to be solved by the invention]

In view of the above, the present invention focuses on the characteristics of the recording and reproduction by the PCM signal, and feeds the magnetic tape as described in the above publication by intermittently feeding the magnetic tape by one track to record and reproduce the PCM signal. It has been proposed for the purpose of providing a recording / reproducing apparatus capable of recording a digital signal such as a correct PCM signal without error by using the system without changing the arrangement order of recording tracks.

[Means for solving the problem]

The helical scan recording / reproducing apparatus according to the present invention has at least one rotating head that rotates a tape-shaped recording medium wound around a rotating drum in synchronization with the rotating drum in order to achieve the above-described object. Feed means for intermittently feeding one track at least when it is not in contact with the tape-shaped recording medium; and detecting means for detecting the rotation of the rotary drum and generating a detection output for each rotation of the rotary drum And selectively switching between a recording state for supplying a digital signal to the rotary head and a reproduction state for reproducing a digital signal read from a tape-shaped recording medium by the rotary head for each detection force from the rotation detecting means. Recording / reproducing means for performing, and an error detecting means to which a reproduced signal output from the recording / reproducing means is supplied and for performing error detection of the supplied reproduced signal The digital signal recorded on the tape-shaped recording medium by the preceding recording operation by the rotary head by the error detecting means has an error in the signal read from the tape-shaped recording medium by the reproducing operation by the subsequent rotary head. If not detected, the feeding means is controlled to skip the tape-shaped recording medium by one track, and the digital signal recorded on the tape-shaped recording medium by the preceding recording operation by the rotary head by the error detecting means. When an error is detected in the signal read from the tape-shaped recording medium by the reproducing operation by the subsequent rotary head, the feeding of the tape-shaped recording medium by the feeding means is stopped,
A digital signal is again supplied from the recording / reproducing means to the rotary head and recorded on the same track of the tape-shaped recording medium.

[Action]

The recording / reproducing apparatus of the helical scan system according to the present invention reads the digital signal recorded on the tape-shaped recording medium by the preceding recording operation by the rotary head by the error detecting means from the tape-shaped recording medium by the reproducing operation by the subsequent rotary head. When no error is detected in the output signal, the feeding means is controlled to feed the tape-shaped recording medium by one track. Also, when an error is detected in the signal read from the tape-shaped recording medium by the reproducing operation of the subsequent rotating head, the digital signal recorded on the tape-shaped recording medium by the preceding recording operation by the rotating head is detected by the error detecting means. Then, the feeding of the tape-shaped recording medium by the feeding means is stopped, and the digital signal is again supplied from the recording / reproducing means to the rotary head and recorded on the same track of the tape-shaped recording medium.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

The recording / reproducing apparatus according to the present invention comprises, as shown in FIG.
A magnetic drum 1 as a recording medium is provided with a rotating drum 2 on which a magnetic tape 1 is obliquely wound over a predetermined angle range. The rotating drum 2 includes, for example, a PCM signal obtained by digitizing an audio signal as an analog signal by the magnetic tape. 1 and a rotary head 3 for reproducing the recorded signal. The rotary head 3 is coaxially arranged so as to be able to rotate in synchronization with the rotary drum 2, and is used for both recording and reproduction in the present embodiment.

The magnetic tape 1 is pulled out of the supply reel 13 into a cassette half 4 mounted opposite to the rotary drum 2 and set on a tape guide 12 in the cassette half 4 and a tension arm 10 provided on the apparatus side. The tape is wound around the rotary drum 2 via the tape guide 11 and the inclined guide 9 provided on the entrance side of the rotary drum 2. The magnetic tape 1 coming out of the rotary drum 2 is taken up by the take-up reel 5 in the cassette half via the tape guide 6 in the inclined guide 8 and the cassette half 4 provided on the outlet side of the rotary drum 2. . The magnetic tape 1 traveling along such a tape traveling path is intermittently pinched by a capstan 15 and a pinch roller 16 which are intermittently driven by a stepping motor 14 provided on the outlet side of the rotary drum 2. It is made to run.

The rotary drum 2 is provided with a pulse generator (hereinafter simply referred to as PG) 17 for synchronizing the rotary drum 2 and the rotary drum 3 and detecting the rotational position of the rotary head 3. In this P.G17, the rotary head 3 rotates with the rotary drum 2 in the direction of arrow A in FIG. 2 opposite to the running direction of the magnetic tape. A pulse signal is output at a point where the contact is made.

Then, in the recording / reproducing apparatus configured as described above, the PCM signal is recorded as follows.

First, the magnetic tape 1 is wound around the rotating drum 2, and the rotating head 3 is rotated together with the rotating drum 2.
At this time, the magnetic tape 1 is in a stationary state. When the rotary head 2 reaches a point where the rotary head 2 comes into contact with the magnetic tape 1 from the non-contact area, a pulse signal is output from P.G17 as shown in FIG. Simultaneously with the output of the pulse signal (P _S ), the PCM signal from the memory storing the PCM signal to be recorded is supplied from an input terminal 18 via an amplifier 19 as shown in FIG. Supplied to 20. When the first pulse signal (P _S ) is output,
The recording or reproduction switching circuit 20 has been switched to the recording mode. Here, the PCM signal is supplied as a recording signal to the rotary head 3 via the recording or reproduction switching circuit 20, as shown in FIG. 3, and is recorded on the magnetic tape 1.

Further, the rotating drum 2 and the rotating head 3 make one rotation,
When the rotary head 3 comes into contact with the magnetic tape 1, a second pulse signal (P _S ) is output from P.G17 as shown in FIG. When the pulse signal (P _S) is outputted,
The recording or reproduction switching circuit 20 is switched to the reproduction mode, and the recording track on the magnetic tape 1 previously recorded by the rotary head 2 is reproduced. This reproduced signal is
The signal is supplied from the recording or reproduction switching circuit 20 to an error detecting means (CRC) 22 via an amplifier 21. Here, error detection of the reproduced signal is performed. The reproduction signal is output from the output terminal 23, and the error detection output controls the stepping motor 14 and a changeover switch 25 provided in a 24-hour stepping motor control circuit (SG) for controlling the rotation of the stepping motor 14. . If no error is detected by the error detecting means 22, the changeover switch is turned on, and the output from the stepping motor control circuit 24 is supplied to the stepping mower 14 via the amplifier 26, 14
Rotates the capstan 15 by a predetermined angle to intermittently feed the magnetic tape 1 by one track.

When an error is detected by the error detecting means 22, an error detection output is output as shown by a broken line in FIG. 3, the changeover switch 25 is turned off, and the output from the stepping motor control circuit 24 is supplied to the stepping motor 14. However, the rotation of the stepping motor 14 is stopped, and the magnetic tape 1 is not fed.

Then, the rotating head 3 comes into contact with the magnetic tape 2 again,
When the pulse signal is output, the same PCM signal as the signal to be recorded earlier is recorded on the magnetic tape 1. By repeating this operation, recording and reproduction are repeated until no error is detected by the error detection means 22,
When no error is detected, the magnetic tape 1 is intermittently advanced by one track.

Therefore, in the recording / reproducing apparatus, the magnetic tape 1 is skipped by one track on the condition that no error is detected in the recorded signal.

In the above description, an example in which the rotary head 3 is used for both recording and reproduction has been described, but independent rotary heads may be used for recording and reproduction. In this case, the rotation of the rotary drum 2 causes the magnetic tape 1 to be skipped by one track.

Further, it can correspond to various digital signals as signals to be recorded.

〔The invention's effect〕

As described above, the helical scan recording / reproducing apparatus according to the present invention actually reproduces a digital signal recorded on a tape-shaped recording medium, and determines whether or not an error is detected in the reproduced digital signal. Since it is detected whether or not the digital signal has been successfully recorded on the shape recording medium, the time for reverberating the quality of the recording can be shortened,
In addition, it is possible to accurately detect whether or not the recording on the tape-shaped recording medium is good.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram showing a recording / reproducing system of a recording / reproducing apparatus according to the present invention, and FIG. 2 is a schematic view of a magnetic tape feeding mechanism of the recording / reproducing apparatus. FIG. 3 is a diagram for explaining recording / reproduction of a signal and a state of feeding a magnetic tape. 1 magnetic tape 2 rotating drum 3 rotating head 14 stepping motor 17 pulse generator 22 error detecting means

Claims (1)

(57) [Claims] When the at least one rotary head that rotates a tape-shaped recording medium wound around a rotary drum in synchronization with the rotary drum is at least in a non-contact state with the tape-shaped recording medium, only one track is provided. Intermittent feeding means; detecting means for detecting the rotation of the drum and generating a detection output for each rotation of the rotating drum; digital signal to the rotating head for each detecting force from the rotation detecting means. A recording / reproducing means for selectively switching between a recording state to be supplied and a reproduction state for reproducing a digital signal read from a tape-shaped recording medium by the rotary head; and a reproduction signal output from the recording / reproduction means. And
Error detection means for detecting an error in the supplied reproduction signal, wherein the error detection means reproduces the digital signal recorded on the tape-shaped recording medium by the preceding recording operation by the rotary head by the subsequent rotary head. When no error is detected in the signal read from the tape-shaped recording medium, the feeding means is controlled to skip the tape-shaped recording medium for one track, and the error detecting means controls the rotation of the rotary head. When an error is detected in a signal read from a tape-shaped recording pair by a subsequent reproducing operation by the rotary head, a digital signal recorded on a tape-shaped recording medium by a preceding recording operation is detected. Stop the feeding of the medium and send the digital signal again from the recording / reproducing means. A helical scan type recording / reproducing apparatus, wherein the helical scan type recording / reproducing apparatus supplies the data to the rotary head and records the data on the same track of a tape-shaped recording medium.