KR960012994B1 - Recording and reading apparatus of vcr - Google Patents

Abstract

The apparatus is designed to record and play video signal on a VCR tape. The apparatus comprises: heads for play only (20),(21) for playing a signal being recorded at the position delayed by a specific angle from record/play head simultaneously; the first and the second switches (S1, S2) for receiving signal played by a head for record and play (5), (6) in case of performing play only, and receiving signal played by the heads for play only (20), (21) in case of performing play/record function simultaneously.

Description

VCR recording and reproducing apparatus

1 is a detailed block diagram showing a recording and reproducing apparatus of a conventional VCR.

2 is an arrangement diagram of a video head of the prior art.

3 is a detailed block diagram showing a recording and reproducing apparatus of the VCR of the present invention.

4 is an arrangement diagram of a video head of the present invention.

5 is a video track configuration diagram according to the present invention.

* Explanation of symbols for main parts of the drawings

1: luminance signal recording unit 2: color signal recording unit

3: mixing section 4, 7, 8: amplifying section

5,6 recording and playback head 9: channel switch

10 luminance device reproducing unit 11 color signal reproducing unit

12: switching unit 13: head drum

20, 21: Play head S1, S2, S3: Selection switch

The present invention relates to a recording and reproducing apparatus for a VCR, and more particularly to a recording and reproducing apparatus capable of simultaneously reproducing a video signal on a tape.

In the conventional VCR recording and reproducing apparatus, as shown in FIG. 1, the luminance signal recording unit receives an external video signal, passes only the luminance signal, and then performs FM conversion, and removes and outputs a component overlapping the frequency band of the color signal. 1), a color signal recording unit 2 for receiving an external video signal and passing only a color signal, and then outputting the frequency signal by performing low frequency conversion, and a mixing unit 3 for synthesizing the output signals of the luminance signal recording unit 1 and the color signal recording unit 2; ), The recording amplifying section 4 which amplifies the output of the mixing section 3, and the output of the recording amplifying section 4 are recorded on a tape to reproduce the video signals recorded in channels 1 and 2 on the tape, Two recording and playback heads 5 and 6 to output, two playback amplifiers 7 and 8 for amplifying the video signals reproduced by the recording and playback heads 5 and 6, respectively, and the playback amplifier section Channel 1 video scene output from (7) And a channel switch 9 for converting the channel 2 video signal output from the reproduction amplifier 8 into a continuous signal by a 30HZ pulse signal, and outputting only the luminance signal from the output signal of the channel switch 9; After the FM demodulation outputs the luminance signal reproducing unit 10, the color signal reproducing unit 11 for passing only the color signal of the output signal of the channel switch 9 and restoring to the carrier frequency of the original color signal and outputting the external video signal. It is composed of a switching unit 12 that outputs directly or outputs the combined output of the luminance and color signal reproducing units 10 and 11.

At this time, the recording and reproducing head 5 of channel 1 and the recording and reproducing head 6 of channel 2 are positioned on the head drum 13 at 180 ° intervals (FIG. 2) to be inclined with respect to the running direction of the tape. Record and play back the signal.

The operation of the recording and reproducing apparatus of the prior art configured as described above is as follows.

When a video signal obtained by combining the luminance signal and the color signal is applied from the outside, the luminance signal and the color signal are separated by the luminance signal and the color signal recording unit (1, 2), respectively. It is difficult to output by modulating the FM, and the color signal is output by converting the frequency low-frequency in order to save the recording band and reduce the influence of the time axis during reproduction.

By the mixing section 3 and the recording amplifier 4, the outputs of the luminance signal and the color signal recording sections 1, 2 are mixed and amplified and recorded on the tape by the recording and reproducing heads 5,6. .

The video signal recorded on the tape is reproduced by the recording and reproduction heads 5 and 6, respectively, and amplified by the reproduction amplifiers 7 and 8 and transmitted to the channel switch 9 by a pulse signal of 30 HZ. The signals of channel 1 and channel 2 are made into one continuous playback signal.

That is, when the pulse signal of 30HZ is set to low, channel 1 is selected, and if it is set to high, channel 2 is selected to continuously output signals to the luminance and color signal reproducing units 10 and 11. To transmit.

The reproduced video signal is signal-processed by the luminance signal and color signal reproducing units 10 and 11, demodulated into the original video signal, transmitted to the switching unit 12, and output according to the selection of the switching unit 12. .

However, in the case of the conventional VCR, it is composed of only a head for both recording and reproducing, so as to record a video signal by operating as a recording head during recording, and to reproduce a video signal by operating as a playback head during reproduction.

Therefore, during recording, the video signal recorded on the tape cannot be reproduced. After the recording is finished, the tape must be rewound and played back to the initial position. There was a problem that became impossible.

The present invention has been conceived to solve the above problem, and in a VCR having a recording / reproducing head (5) (6), a signal for recording at a position which is backward by a predetermined angle (θ) from the recording / reproducing head. A playback-only head 20 and 21 for simultaneously reproducing the audio signal; and a playback-only head for receiving signals reproduced by the recording and playback heads 5 and 6 when reproducing only and reproducing at the same time as recording. Provided is a recording and reproducing apparatus for a VCR equipped with first and second selection channel switches (S1, S2) for receiving a signal reproduced in (20) and (21) so as to reproduce a video signal being recorded during recording. Has its purpose.

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

3 is a detailed configuration diagram showing an embodiment of the present invention, in which the recording and reproducing head 5 and the channel 1 reproducing head 20 are mounted on the head drum 13 so that the interval between the recording and reproducing heads is maintained. Channel 2 playback-only head 21 mounted on the head drum 13 at an interval of 180 ° with the channel 1 playback-only head 20, and playback signals of the recording and playback heads 5 and 6 when only playback is performed. Are transmitted to the reproducing amplifiers 7 and 8, respectively, and when reproducing while recording, the reproducing signals of the channel 1 and channel 2 reproducing heads 20 and 21 are respectively reproduced. 2H selector signals (S1, S2), 30HZ pulse signal is transmitted to the channel switch (9) for reproducing only, and 30HZ pulse signal is delayed by θ angle for reproducing while recording. It is configured by further adding a selection switch S3 for transmitting to the channel switch 9.

At this time, the recording and playback heads 5 and 6 and the playback-only heads 20 and 21 have a mechanical position difference of θ (Fig. 4), so that the video recorded by the recording and playback heads 5 and 6 is recorded. The signal tracks A and B and the video signal tracks A 'and B' reproduced by the reproduction-only heads 20 and 21 generate gaps proportional to mechanical position differences. The width of the read-only heads 20 and 21 is made smaller than the width of the recording and playback heads 5 and 6 (FIG. 5) to prevent invasion of adjacent tracks so as to prevent crosstalk.

The operation of the present invention configured as described above is as follows.

First, the video signal input from the outside is converted into a recording current by the luminance signal and color signal recording units 1 and 2 and the mixing unit 3, and amplified by the recording amplifier 4, and then the channel 1 and The recording and playback heads 5 and 6 of channel 2 record one frame of each field in one row of video tracks on the tape.

When the video signal is to be reproduced while recording the video signal on the tape as described above, the video signal being recorded by the recording and reproducing heads 5 and 6 by connecting the selection switches S1 and S2 to one contact point a. Is reproduced by the read only heads 20 and 21 of the channel 1 and the channel 2, and transmitted to the recording and reproducing amplifiers 7 and 8.

The reproduced video signals of channel 1 and channel 2 are amplified and output by the reproduction amplifiers 7 and 8, respectively, and transmitted to the channel switch 9, wherein the reproduction-only heads 20 and 21 record and reproduce. Since the rotation is delayed by θ than the heads 5 and 6, the selector switch S3 applies a pulse signal to the channel switch 9 by 30HZ delayed by a time of θ angle, so that the channel switch 9 is rotated by θ angle. Receive the video signals of channel 1 and channel 2 at a rate of 30HZ delayed by the time of.

In addition, in order to reproduce the video signal of which recording has been completed on the tape, each of the selection switches S1 and S2 is connected to the other contact point b, and the selection switch S3 transmits a 30HZ pulse signal to the channel switch 9. In this case, the same operation as described above is performed.

As described above, the present invention has the effect that it is possible to immediately recognize whether or not the VCR is recording well by playing back the video signal recorded during the recording of the VCR at the same time.

Claims (2)

In a VCR having a recording / reproducing head (5) 6, a reproduction-only head (20) (21) for simultaneously reproducing a signal to be recorded at a position later than the recording / reproducing head by a small angle (θ). To receive the signal reproduced by the recording and reproducing heads 5 and 6 when reproducing only, and to receive the signal reproduced by the reproducing heads 20 and 21 when reproducing simultaneously with recording. Recording and reproducing apparatus for a VCR, comprising first and second selection switches (S1, S2). 3. A recording and reproducing apparatus for a VCR according to claim 2, wherein said reproducing head (20, 21) is smaller than the width of said recording and reproducing head (5, 6).