JPS63121151A - Magnetic recorder - Google Patents

Abstract

PURPOSE:To prevent erroneous recording, by enabling recording to be performed by selecting only a standard mode in a standard cassette, and selecting the standard mode and a high picture quality mode in a high performance cassette by a selection switching means, and ejecting a cassette if a selection switch is set at the high picture quality mode when the standard cassette is mounted. CONSTITUTION:At the time of recording, the standard cassette and the high performance cassette are discriminated automatically respectively at a cassette discrimination circuit 13 and a switch 14, and a mode can be switched to respective recording mode, and also, when the high performance cassette is mounted, the mode is switched to a standard recording mode and a high picture quality recording mode selectively by the selection switch 60. At this time, when the standard cassette is mounted, and the high picture quality mode is set by the selection switch, the cassette is ejected. In such way, the erroneous recording on the standard cassette can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording device, and more particularly to a magnetic recording device that records by automatically switching between two modes with different carrier wave frequencies.

Conventional Technology Currently, in home VTRs that use 1/2 inch wide tape, the coercive force HC is approximately 600 (Oe) to 750 [Oe].
e], the residual magnetic flux density B' is approximately 1100 (Gauss) ~ 13
00 (Gauss) iron oxide magnetic tape (hereinafter referred to as standard magnetic tape), approximately 3.4M
Recording is performed using a carrier wave frequency set between Hz and 5.5 MHz (for example, 3.4 MHz to 4.4 MHz), but in recent years, the performance of magnetic tapes and magnetic heads has improved, and the resolution has increased. High resolution V
TR was becoming more and more requested.

Therefore, instead of the standard magnetic tape mentioned above, currently 8 try
The coercive force Hc used in s VTRs, commercial VTRs, etc. is approximately 13G0 (Oe) ~ 1500 (Oe
), the residual magnetic flux density 3r is approximately 2700 (Gauss) ~
A metal tape with a high coercive force HC such as 2800 [Gauss] and a high residual magnetic flux density B is used, and this metal tape has a carrier wave frequency ( For example, 5M
VTR that records at a frequency of Hz to 7MHz)
Various things are being considered.

However, if the recording/playback mode of the current 1/2-inch home VTR is set to standard need, and the recording/playback mode with a higher carrier wave frequency is set to high-quality mode, the carrier wave frequencies of these two modes are significantly different from each other, so each mode There is no compatibility between the recorded signals.

Moreover, the existing high-performance magnetic tapes such as the metal tapes used in the above-mentioned 8 m VTRs and commercial VTRs have a coercive force HC of approximately 130G (Oe) or more, which is much higher than the above-mentioned standard magnetic tapes. Therefore, this tape is
When used in a 2-inch home VTR, not only will head saturation occur and the desired characteristics cannot be obtained, but the long wavelength characteristics (linear audio characteristics) and erasing characteristics associated with recording and reproducing audio signals will be inferior, among other problems. It is not suitable for standard mode because it causes problems, and can only be used for high-quality mode. On the other hand, standard magnetic tape cannot be used in high-quality mode due to its performance, but can only be used in standard mode.

Therefore, in order to satisfy the above-mentioned demand, a high-definition compatible VTR newly equipped with a high-definition mode recording and reproducing means and the above-mentioned 8.
It would be sufficient to provide a high-performance cassette containing the metal tape used in m-VTRs and commercial VTRs, but in this way, users would be forced to use VTRs that are compatible with each mode and other types of VTRs that are not compatible with each other. cassette is required, making it very inconvenient to use.

Therefore, while we provide a VTR equipped with image recording and reproducing means for the above-mentioned standard mode and high-quality mode and a switch for switching between these two modes, we also provide a high-quality VTR that accommodates the metal tape used in 8txa VTRs and commercial VTRs. It is conceivable that the performance cassette be made to have the same shape as the current standard cassette that stores the standard magnetic tape, so that the user can distinguish between the standard cassette and the high performance cassette and switch to any mode.

Problems to be Solved by the Invention However, in this case, since the cassette cases have approximately the same shape, it is possible to make a mistake in determining whether the cassette is a standard cassette containing a standard magnetic tape or a high-performance cassette containing a high-performance magnetic tape. It's very troublesome to identify and judge each one one by one and switch modes. There is a problem in that it is easy to make mistakes such as setting and recording.

In addition, it is highly conceivable that users who own current VTRs will purchase and use high-performance cassettes of the same shape in the near future. Not desirable.

The present invention stores a magnetic tape capable of recording in both modes in a high-performance cassette, automatically distinguishes between a standard cassette and a high-performance cassette during recording, and at the same time, selects only the standard mode for the standard cassette and selects a selection switch for the high-performance cassette. The magnetic tape allows you to select between standard mode and high-quality mode for recording, while also ejecting the cassette when the selection switch is set to high-quality mode when a standard cassette is attached to prevent erroneous recording. The purpose is to provide a recording device.

Means for Solving the Problems In FIG. 1, the cassette discrimination circuit 13 detects the presence or absence of a cassette discrimination hole in the installed cassette and determines whether a cassette, a standard cassette or a high-performance cassette, is installed in the device. The selection switch 60 is a switch means for selecting between the standard recording mode and the high quality recording mode, and the inverter 61. ANDGATE 62. switch 1
4 switches to the standard recording mode when the cassette is determined to be a standard cassette by the cassette discriminating means, while switching to the standard recording mode when the cassette is determined to be a high-performance cassette by operating the selection switch means to select between the standard recording mode and the high-quality recording mode. Inverter 70. ANDGATE 71. or gate 7
2. The eject control signal output terminal 73 is a means for ejecting the cassette before starting a recording operation or when a recording operation is performed when it is determined that a standard cassette is installed and the high image quality mode is set. be.

The high-performance cassette contains a magnetic tape capable of recording in both modes, so it can be used with both current VTRs and this device.When recording, the cassette discrimination circuit 13 and switch 14
! It is possible to automatically distinguish between a cassette and a high-performance cassette and switch to the respective recording mode, and when the cassette is a high-performance cassette, the selection switch 60 selectively switches between the standard recording mode and high-quality recording mode. Particularly, when a standard cassette is installed and the high image quality mode is set by the selection switch, the cassette can be ejected to prevent erroneous recording on the standard cassette.

Embodiment Fig. 3 shows a standard cassette 1, which currently has a 1/2 inch household V
Iron oxide magnetic tape used in TR (coercive force is approximately 6
0G (Oe) to 730 (Oe) and a residual magnetic flux density of approximately 1100 (Gauss) to 1300 (Gauss)). In the figure, 2a and 2b are shaft holes, 3 is a recess for inserting a capstan, 4a and 4b are recesses for inserting a tape pull-out member, 5 is a lid, and 6 is a recess for preventing incorrect insertion.

Figure 4 shows high-performance cassette 7, which is approximately the same as standard cassette 1.
It houses a high-performance magnetic tape, which will be described later. In the figure, reference numeral 6a denotes a cassette identification hole, which is provided in a part of the recess 6 for preventing erroneous insertion.

Note that the high-performance magnetic tape stored in the high-performance cassette 7 has a recording wavelength of a luminance signal of 1.3 μm.

At 0.97μm and 0.73μm, the current 1/
The reproduction output value when recording with a current approximately 20% higher than the optimum recording current value of the standard tape used in a 2-inch home VTR is at least 7d3. 8.5J3.1OcE is large, and in order to make the audio signal erasure rate better than 165 output, for example, a CO-coated iron oxide magnetic material is used for the magnetic layer, and the coercive force is 750 (Qe) to 950 (Qe). Oe), the residual magnetic flux density is at least 1250 Gauss or more and the grain length of the magnetic layer is at least 0.2 μm or less, or the magnetic layer is made of a metal magnetic material and the coercive force is 700 (Qe) to 8
50 (Qe), residual magnetic flux density is 2600 (Gauss) ~
2800 (Gauss), the grain length of the magnetic layer is at least 0
．． It is formed to have a thickness of 16 μm or less. This high-performance magnetic tape is capable of recording in both standard recording mode and high-quality recording mode.

FIG. 1 is a block system diagram of one embodiment of the device of the present invention, and FIG.
The figure shows a schematic plan view thereof. In Fig. 2, reference numeral 8 denotes a cassette discrimination bottle, which is configured to move up and down by the action of a spring, for example, and is provided at a position facing the cassette discrimination hole 6a when a high-performance cassette 7 is installed. There is. 60 is a selection switch for selecting between standard recording mode and high-quality recording mode, 63 is an input signal changeover switch to be described later, which is provided on the front of the panel, and 74 is an eject mode signal input terminal.

Here, when the standard cassette 1 is installed in the device shown in FIG. 2, the cassette discrimination pin 8 is displaced downward,
As a result, the standard cassette switching signal (L level signal) is taken out from the cassette discrimination circuit 13 shown in FIG.
connected to the standard mode. On the other hand, when the high-performance cassette 7 is installed in the device shown in FIG.
H level) is taken out, and the switch 14 is connected to terminal B by the H level output of the AND gate 62 to enter the high image quality mode. However, if you want to record in standard recording mode even though a high-performance cassette is installed, select switch 6.
Manipulate 0. As a result, the H level signal is taken out from the switch 60, the inverter 61 sets it to the L level, the AND gate 62 is set to the L level, and the switch 14
is connected to the terminal and becomes standard mode.

In this way, simply by loading different types of cassettes into the device, the mode can be automatically switched to the respective mode. In this case, since the cassette discrimination hole 6a is protected by the stepped portion of the erroneous insertion prevention recess 6, the intrusion of dust and the like can be prevented as much as possible. Furthermore, when the cassette is inserted into the installed holder, the cassette identification bin 8 and the cassette identification hole 6a engage with each other at the same time as the holder descends. Both act as guides to ensure engagement between the two. Furthermore, when a high-performance cassette is installed, the standard mode and high-quality mode can be freely selected by operating the selection switch 60.

By the way, in the device of the present invention, when a standard cassette is loaded and the selection switch 60 is operated to the high-quality mode side, the AND gate 71 is activated by the L level output of the cassette discrimination circuit 13 and the L level output of the selection switch 60. The output is set to H level (the output of inverter 70 is H level), the output of OR gate 72 is taken out from eject control signal output terminal 73, and the standard cassette is ejected.

In this way, when the standard cassette is installed and the high-quality mode is selected, the operator can eject the standard cassette if the selection switch 60 is provided on the front panel (Fig. 2). This is to prevent erroneous recording from occurring if the user misunderstands that not only standard cassettes can be used for recording in both standard mode and high-quality mode.

In this case, if the standard cassette is not ejected, the cassette will be automatically recorded in the standard mode by the cassette discrimination, but if you do this, the actual recording mode and the display on the selection switch 60 will be different and it will appear as though the recording mode is high. This is not desirable because it may give the misunderstanding that recording is being performed in the image quality mode, or that recording in both modes is possible even with a standard cassette as described above.

Next, a method of recording using different carrier frequencies according to each mode will be described. In FIG. 1, when the input movie signal to be handled is a composite video signal, the switch 63 is connected to terminal A, and when it is a luminance signal @/chroma signal separate video signal, the switch 63 is connected to the terminal port. For example, a composite video signal inputted to the terminal 9 is supplied to a low-pass filter and comb filter 10a having a cutoff frequency of, for example, about 3 MHz and a low-pass filter and comb filter 10b having a cutoff frequency of, for example, about 5 MHz. Here, the luminance signal components are respectively pre-emphasis circuits 11a.

The high frequency is enhanced in 11b, and the FM modulator 12a.

12b. The FM modulator 12a performs FM modulation using a carrier wave frequency of 3.4MH2 to 4.4MH2 as described later to produce a standard mode FMi degree signal, while the FM modulator 12b uses a carrier wave frequency of 5.0M.
FM modulation is performed using Hz to 6.7 MHz to produce an FM luminance signal in a high image quality mode, which is supplied to an adder 15 via a switch 14 that is switched according to each mode.

The frequency spectrum of the FM luminance signal is as shown in Figure 5 in the standard mode, and as shown in the figure in the high-quality mode, the carrier frequency is set higher than in the standard mode, and the deviation is also It is set wider than standard mode.

In the frequency spectrum of the tFM 1 degree signal shown in Fig. 5,
fAs, fAP, and fAW indicate the carrier wave frequencies at the sync tip level S, pedestal level P, and white peak level W of the luminance signal shown in FIG. 6, and similarly, f[3s, fE]P and few
The carrier frequency at the sync tip level S, pedestal level P, and white peak level W of the li degree signal is shown. For example, the carrier frequency fAS in standard mode is 3
．． 4MHz, fAP is 3.8MH2, fAw is 4.4MHz, and the above carrier frequency fes in high image quality mode is 5.0MHz, fep is 5.6M
H2°fBW is 6.7 MHz.

As can be seen from FIG. 5, at the carrier frequencies fAP and fBP corresponding to the pedestal level, there are also frequency components of the sideband of the FM luminance signal of the other mode.
The energy of the carrier frequencies fAP and fBP is sufficiently larger than the energy of the sideband component of the same frequency in the other mode. At the time of reproduction in the present invention, mode discrimination is performed with attention paid to this point.

On the other hand, the video signal input to the terminal 9 is converted into a chroma signal by a bandpass filter 16, subjected to signal processing by a recording chroma processing circuit 17, and then added to an FM luminance signal by an adder 15. The output of the adder 15 is amplified by the recording amplifier 18, supplied to magnetic heads 191 and 192, and recorded on the magnetic tape 20.

In the case of separate video signals, the luminance signal input to the terminal 9y and the chroma signal input to the terminal 9C are processed in the same manner as described above.

Further, the recording amplifier 18 may change the characteristics and magnitude of the recording current according to the characteristics of the magnetic tape used, for example, for each magnetic tape such as a standard magnetic tape and a high-performance magnetic tape. It is also possible to provide recording amplifiers each having a desired characteristic and size set according to the characteristics of the recording amplifier, and to switch these amplifiers by the output signal of the AND gate 62.

In the above embodiment, the cassette identification hole 6a was provided in the recess 6 for preventing erroneous insertion on the bottom of the cassette to determine the type of cassette, but in the next embodiment, a hole 6a was provided in the recess 6 for preventing incorrect insertion on the bottom of the cassette. The type of cassette is determined by the provided determination hole.

FIG. 8 shows a standard small cassette 68 in which a standard magnetic tape is stored. FIG. 9 shows a high-performance small cassette 69, which stores a high-performance magnetic tape capable of recording in both standard recording mode and high-quality recording mode, and has a hole 65 for identification on the back side. A high performance small cassette is detected by detecting this discrimination hole 65 using a discrimination switch means such as a leaf spring in the device.

Further, when the small cassette 68, 69 is used by being attached to a standard type VTR, it is housed in an adapter 66 shown in FIG. 10 and attached to the VTR. In this case, when the standard small cassette 68 shown in FIG.
As shown in % (B), the identification hole 67 on the back side of the adapter 66
is closed, while the high-performance small cassette 6 shown in FIG.
9 is attached to the adapter 66, the discrimination hole 67 on the back surface of the adapter 66 is opened as shown in FIG. 10(B). By detecting the opening and closing of the discrimination hole 67, the standard small cassette 68 or the high performance small cassette 69 is discriminated.

In this way, the device of the present invention automatically switches modes just by installing a cassette, so there is no need to carefully identify each cassette and switch modes. No matter what you do, you won't make the mistake of recording in high quality mode.

Furthermore, when a high-performance cassette is installed, by operating the selection switch 60 as desired, it is possible to select and record in both modes, which can be effectively used, for example, when it is desired to play back on a current VTR.

In addition, in this example, when a standard cassette or a standard small cassette is loaded into the device and high image quality mode recording is selected, the explanation was given to eject the cassette before starting the recording operation. The ejection may be performed at the same stage.

Effects of the Invention According to the device of the present invention, it is easy to use because there is no need to perform complicated operations such as identifying each cassette one by one and switching modes during recording. In addition, the high-performance cassette can record in both modes, so it can be used with current VTRs without any problems.Furthermore, when the high-performance cassette is installed, you can select either mode by operating the selection switch. It is easy to use from this point of view as well, and when a standard cassette is installed and the high image quality mode is set, the cassette can be ejected to prevent erroneous recording to the standard cassette. It has the following features.

[Brief explanation of the drawing]

1 and 2 are respectively a block system diagram and a schematic plan view of an embodiment of the device of the present invention, FIG. 3 is a perspective view of a standard cassette, FIG. 4 is a perspective view of a high performance cassette, and FIG. 5 is F
Frequency spectrum of M luminance signal, Fig. 6 is a luminance signal waveform diagram, Fig. 7 is a perspective view of a small cassette, Figs. 8 and 9
The figures are perspective views of a standard small cassette and a high-performance small cassette, respectively, and FIG. 10 is a perspective view of an adapter for small cassettes. 1.68... Standard cassette, 6... Four parts to prevent incorrect insertion, 6a, 65.67... Hole for cassette identification, 7°6
9... High performance cassette, 8... Cassette discrimination bin, 9.9y, 9c... Video signal input terminal, 10a. 10b...Low pass filter and comb filter, 12a
. 12b... FM modulator, 13... Cassette discrimination circuit, 14... Switch, 60... Selection switch, 61
゜70... Inverter, 62.71... AND gate, 63... Input signal changeover switch, 66... Adapter, 72... OR gate, 73... Eject control signal output terminal, 74...・Eject mode signal input terminal. Patent applicant: Victor Japan Co., Ltd. *3I″1 Figure 5 Isamu 101

Claims (1)

[Claims] A standard cassette containing a standard magnetic tape capable of recording only in a standard recording mode of a predetermined carrier wave frequency, the standard recording mode, and a carrier wave frequency set to a higher carrier wave frequency than the carrier wave frequency in the standard recording mode and a deviation wider than that deviation. A high-quality magnetic tape is stored in which the coercive force, residual magnetic flux density, and particle length are set to enable recording in both high-quality recording modes.
A magnetic recording device capable of mounting both a high-performance cassette having a cassette discrimination hole in the cassette housing to distinguish it from the standard cassette, and which detects whether or not the installed cassette has the cassette discrimination hole. cassette discriminating means for detecting and determining which cassette, the standard cassette or the high-performance cassette, is installed in the apparatus, and selection switch means for selecting a standard recording mode or a high-quality recording mode, When the cassette is determined to be the standard cassette by the cassette discriminating means, the cassette is switched to the standard recording mode, while when it is determined to be the high-performance cassette, the selection switch means is operated to switch between the standard recording mode and high image quality. When the standard cassette is determined by the means for switching to the recording mode and the cassette discriminating means, and the high image quality mode is set by the selection switch means, before or when the recording operation is performed. and an eject means for ejecting the loaded cassette, the standard cassette can record only in the standard recording mode, and the high-performance cassette can record selectively between the standard recording mode and the high-quality recording mode. A magnetic recording device characterized by being configured as follows.