GB2272100A - Rotary head assembly power supply and control circuits - Google Patents
Rotary head assembly power supply and control circuits Download PDFInfo
- Publication number
- GB2272100A GB2272100A GB9322503A GB9322503A GB2272100A GB 2272100 A GB2272100 A GB 2272100A GB 9322503 A GB9322503 A GB 9322503A GB 9322503 A GB9322503 A GB 9322503A GB 2272100 A GB2272100 A GB 2272100A
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- United Kingdom
- Prior art keywords
- signal
- recording
- rotary transformer
- reproducing
- switching
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Classifications
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B33/00—Constructional parts, details or accessories not provided for in the other groups of this subclass
- G11B33/12—Disposition of constructional parts in the apparatus, e.g. of power supply, of modules
- G11B33/121—Disposition of constructional parts in the apparatus, e.g. of power supply, of modules the apparatus comprising a single recording/reproducing device
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- A—HUMAN NECESSITIES
- A41—WEARING APPAREL
- A41G—ARTIFICIAL FLOWERS; WIGS; MASKS; FEATHERS
- A41G3/00—Wigs
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/02—Control of operating function, e.g. switching from recording to reproducing
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/02—Control of operating function, e.g. switching from recording to reproducing
- G11B15/12—Masking of heads; circuits for Selecting or switching of heads between operative and inoperative functions or between different operative functions or for selection between operative heads; Masking of beams, e.g. of light beams
- G11B15/125—Masking of heads; circuits for Selecting or switching of heads between operative and inoperative functions or between different operative functions or for selection between operative heads; Masking of beams, e.g. of light beams conditioned by the operating function of the apparatus
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/02—Control of operating function, e.g. switching from recording to reproducing
- G11B15/12—Masking of heads; circuits for Selecting or switching of heads between operative and inoperative functions or between different operative functions or for selection between operative heads; Masking of beams, e.g. of light beams
- G11B15/14—Masking or switching periodically, e.g. of rotating heads
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B33/00—Constructional parts, details or accessories not provided for in the other groups of this subclass
- G11B33/12—Disposition of constructional parts in the apparatus, e.g. of power supply, of modules
- G11B33/121—Disposition of constructional parts in the apparatus, e.g. of power supply, of modules the apparatus comprising a single recording/reproducing device
- G11B33/122—Arrangements for providing electrical connections, e.g. connectors, cables, switches
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/008—Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires
- G11B5/00813—Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes
- G11B5/00847—Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes on transverse tracks
- G11B5/0086—Recording on, or reproducing or erasing from, magnetic tapes, sheets, e.g. cards, or wires magnetic tapes on transverse tracks using cyclically driven heads providing segmented tracks
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/02—Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
- G11B5/024—Erasing
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N9/00—Details of colour television systems
- H04N9/79—Processing of colour television signals in connection with recording
- H04N9/87—Regeneration of colour television signals
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Textile Engineering (AREA)
- Recording Or Reproducing By Magnetic Means (AREA)
- Lining Or Joining Of Plastics Or The Like (AREA)
- Helmets And Other Head Coverings (AREA)
Abstract
A video recording and reproducing apparatus includes a rotating assembly A; a fixed assembly B; a plurality of recording and reproducing heads SP1-EP2 mounted on the rotating assembly A; an erasing head FE mounted on the rotating assembly A; a first and second rotary transformer T1, T3 of which the primary windings N11, N31 are mounted on the rotating assembly A and secondary windings N12, N32 are mounted on the fixed assembly B; a control signal generator 400 mounted on the rotating assembly A and connected to the primary winding N31 of the second rotary transformer T3; a first signal processor 100 mounted on the rotating assembly A and connected between the plural recording and reproducing heads SP1-EP2 and the primary winding N11 of the first rotary transformer T1; a switch SW1 connected between the erasing head FE and primary winding N31 of the second rotary transformer T3; a recording and reproducing processor 600 connected to the secondary winding N12 of the first rotary transformer T1; a modulation signal generator 900 connected to the secondary winding N32 of the second rotary transformer T3; and a power supply 500 mounted on the rotating assembly A and connected to the primary winding N31 of the second rotary transformer T3, thereby enabling the use of plural heads SP1-EP2 through one rotary transformer T1. Both control signals and power signals are supplied to the heads via the second rotary transformer T3. <IMAGE>
Description
2272100 RECORDING AND REPRODUCING APPARATUS The present invention relates
to recording and reproducing apparatus.
A general magnetic recording and/or reproducing apparatus such as a video tape recorder (VTR) records and reproduces information by way of a magnetic tape being scanned obliquely by a rotary head for high density recording. Thus, in a conventional VTR. as shown in Figure 1 of the accompanying diagrammatic drawings, rotary heads H I, H2.... Hn and primary windings Nii. N21, Nni of rotary transformers Ti, T2, Tn are mounted on an upside rotary cylinder A of head drum, secondary windings N12, N22.. .. Nn2 of rotary transformers Ti - Tn are mounted on a downside stationary cylinder B. and the rotary heads are electrically connected through the rotary transformers to a head switching and preamplifier circuit C.
Accordingly, equal numbers of rotary transformers and rotary heads are placed in a concentric circular pattern on a plane for a tight coupling between the primary and secondary windings of the rotary transformers. Here, the primary windings of each rotary transformer are placed in a concentric circular pattern in the lower part of the upside cylinder and the secondary windings of each rotary transformer are placed in a concentric circular pattern in the upper part of the downside cylinder.
However, referring to Table I below, showing the number of heads according to the models of rotary head type VTR, the number of heads increases when multifunction and high-quality VTRs are sought, which restricts installation space for rotary transformers having a planar configuration.
TABLE 1
Model type Total Video heads Audio Erasing heads heads heads 2-head 2 2 4-head 4 4 - 4-head 6 4 2 - hi-fi 4-head 7 4 2 1 advanced A 4-head 9 6 2 1 advanced B 1 Also, since the intervals between the windings become narrower, a degradation of the signal-to-noise (S/N) ratio is caused by cross-talk.
Therefore, the circuit design for signal processing is more complex, thereby resulting in a rise in cost.
To solve the above problem. a structure of vertically mounting tiers of rotary transformers has been disclosed in U.S. Patents 4.639,805 and 5,019,926. Also, an art of using optical transmission means instead of a rotary transformer has been disclosed in Japan Patent sho 58-45604.
Meanwhile, U.S. Patent 4.926,273 discloses a mode of transmission of an information signal. operation power signal and control signal through a rotary transformer by a time sharing system, in which an amplifier and a head switching circuit are installed in the upside cylinder of the head drum for a tight coupling between head and amplifier. However, since the power signal is not supplied during a signal transmission period in the conventional time sharing system, a bulky charging circuit and a power stabilizing circuit are necessary in order to supply enough power to a circuit of the upside rotary cylinder. Therefore, the circuit configuration becomes complex and a gain of the power signal needs to be high.
Preferred embodiments of the present invention aim to provide a recording and reproducing apparatus which can reduce the number of rotary transformers by having one rotary transformer shared by a plurality of heads.
Another aim is to provide a recording and reproducing apparatus which can simplify power supply means in a rotating assembly by transmitting the modulated control signals continuously after modulating the erasing and power signals.
According to one aspect of the present invention, there is provided an apparatus for recording and reproducing an information signal to and from magnetic tape. comprising:
a rotatable rotating assembly.
a fixed assembly:
a plurality of recording and reproducing heads mounted on said rotating assembly for recording and reproducing the information signal to and from said magnetic tape; -4 an erasing head mounted on said rotating assembly for erasing the information signal recorded to said magnetic tape; first and second rotary transformers whose primary windings are mounted on said rotating assembly and whose secondary windings are mounted on said fixed assembly; control signal generating means mounted on said rotating assembly and connected to the primary winding of said second rotary transformer for generating switching control signals; first signal processing means mounted on said rotating assembly and connected between said plural recording and reproducing heads and the primary winding of said first rotary transformer for processing an information signal in response to said switching control signals; switching means connected between said erasing head and primary winding of said second rotary transformer for being switch-controlled in response to said switching control signals; 1 recording and reproducing processing means connected to the secondary winding of said first rotary transformer for processing the information signal; modulation signal generating means connected to the secondary winding of said second rotary transformer for modulating an erasing signal and control signal and supplying the modulated signal to the secondary winding of said second rotary transformer. and power supply means mounted on said rotating assembly and connected to the primary winding of said second rotary transformer for supplying operating power voltage to the respective circuit means of the rotating assembly.
Preferably, said first signal processing means includes amplifiers for amplifying the reproduced information signal.
Preferably, said modulation signal generating means comprises:
an oscillator for generating a predetermined first frequency signal as an erasing signal; first frequency-dividing means for frequency- dividing said first frequency signal into a second frequency signal; second frequency-dividing means for frequency-dividing said first requency signal into a third frequency signal, selecting means for selecting said second and third frequency signals in response to said control signal; and a mixer for modulating said first frequency signal with the signal selected from said selecting means and transmitting the modulated signal to the secondary winding of said second rotary transformer.
Preferably, said control signal generating means comprises:
first and second filtering means for filtering a component of said second and third frequency signals from the modulated signal transmitted through said second rotary transformer; comparing means for comparing the detected signals of said first and second filtering means and demodulating said control signal; and decoding means for decoding said demodulated control signal and generating said switching control signals.
Preferably, said power supply means comprises:
a rectifier for rectifying said transmitted and modulated signal; and a capacitor for generating a power voltage by smoothing said rectified signal.
According to another aspect of the present invention, there is provided an apparatus for recording and reproducing video and audio information signals to and from magnetic tape, comprising:
a rotatable rotating assembly; a fixed assembly:
a pair of standard recording and reproducing heads and a pair of longterm recording and reproducing heads mounted on said rotating assembly for recording and reproducing the video information signal to and from said magnetic tape; a pair of audio recording and reproducing heads mounted on said rotating assembly for recording and reproducing the audio information signal to and from said magnetic tape; an erasing head mounted on said rotating assembly for erasing the information signals recorded to said magnetic tape; first, second and third transformers of which primary windings are mounted on said rotating assembly and secondary windings are mounted on said fixed assembly; control signal generating means mounted on said rotating assembly and connected to the primary winding of said third rotary transformer for generating switching control signals; first signal processing means mounted on said rotating assembly and connected between said two pairs of video recording and reproducing heads and the primary winding of said first rotary transformer for selecting a corresponding recording and reproducing head among said two pairs of recording and reproducing heads and processing the video information signal in response to said switching control signals:
second signal processing means connected between said pair of audio recording and reproducing heads and the primary winding of said second rotary transformer for processing the audio information signal in response to said switching control signals, switching means connected between said erasing head and the primary winding of said third rotary transformer for being switching-controlled in response to said switching control signals; video processing means connected to the secondary winding of said first rotary transformer for processing the video information signal; audio processing means connected to the secondary winding of said second rotary transformer for processing the audio information signal; modulation signal generating means connected to the secondary winding of said third rotary transformer for modulating the erasing signal with the control signal and supplying the modulated signal to the secondary winding of said third rotary transformer; and power supply means mounted on said rotating assembly and connected 20, to the primary winding of said third rotary transformer for supplying operating power voltage to the respective circuit means of said rotating assembly.
Preferably, said first signal processing means comprises:
a plurality of amplifiers for amplifying the reproducing signal picked up from the respective heads., a plurality of head switching means for selecting said respective pair of heads; means; a comparator for comparing the outputs of said plural head switching first switching means for selecting recording select switching control signal and output signals of said comparator in response to said switching control signal; second switching means for selecting said plural head switching means in response to the output signal of said first switching means; third switching means for switching the modulated signal transmitted to the primary winding of said third rotary transformer in response to output signal of said first switching means; a fourth switching means for selecting the output signals of said third switching means and said second signal processing means and connecting the selected signal to the primary winding of said second rotary transformer in response to said switching control signals. and a plurality of recording amplifiers for amplifying the signal transmitted to the primary winding of said first rotary transformer and supplying to said respective heads in response to said switching control signals.
Preferably, said video processing means comprises:
a reproducing processing unit connected to the secondary winding of said first rotary transformer for processing and outputting the reproduced video signal, and controlling the phase of a reproduced colour signal by receiving a colour phase control signal during reproduction; a recording processing unit for receiving a video signal, and generating a recording video signal to be supplied to the secondary winding of said first rotary transformer through said first switching means; and colour phase control signal generating means enabled in response to a screen detecting control signal for generating said colour phase control signal by inputting the signal transmitted to the secondary winding of said second rotary transformer and logically synthesizing that signal with the head switching pulse signal and a standard/long-terni select control signal.
is Preferably, said colour phase control signal generating means comprises:
an envelope detector for detecting an envelope by receiving the signal transmitted to the secondary winding of said second rotary transformer; a wave shaper for wave-shaping the output signal of said envelope detector; and a logic synthesis circuit for generating said colour phase control signal by logically synthesizing said wave-shaped signal with said head switching pulse signal and said standard/long-term select control signal.
According to a further aspect of the present invention, there is provided a recording and/or reproducing apparatus having a plurality of recording and/or reproducing heads mounted on a common drum, a first transformer for coupling signals between said drum and a part with respect to which the drum is arranged to rotate, switching means for switching signals between said heads and said first transformer, and a second transformer arranged to couple power and/or control signals between said drum and part.
Such a recording and/or reproducing apparatus may further comprise any one or more of the features disclosed in the accompanying specification, claims, abstract and/or drawings, in any combination.
In preferred embodiments of the present invention, switching means are provided in the rotating assembly so that a plurality of recording and reproducing heads are connected to the fixed circuit assembly through a rotary transformer, and power and switching control signals are supplied from the fixed circuit assembly to the rotating assembly through another rotary transformer. Therefore. since fewer rotary transformers than recording and reproducing heads are installed, many more heads can be easily mounted on the rotating assembly. Also, since power can be supplied continuously using the erasing rotary transformer (not the recording and reproducing rotary transformer), the design of a power supply circuit to be installed in the rotating assembly becomes simplified.
For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to Figures 2 to 8 of the accompanying diagrammatic drawings. in which:
Figure 2 is a block diagram showing the configuration of one example of a 7-head type VTR according to the present invention; Figure 3 is a detailed circuit diagram of a modulation signal generator 5 shown in Figure 2; Figures 4A to 4D illustrate the waveforms of various sections shown in Figure 3; Figure 5 is a graph showing the frequency characteristics of a modulation signal in an example of the present invention; Figure 6 is a detailed circuit diagram of a control signal generating circuit shown in Figure 2, in Figure 7.
Figure 7 is a detailed circuit diagram of a colour phase control signal generator; and Figures SA to 8G illustrate the waveforms of various sections shown A preferred embodiment of the present invention will now be described in detail hereinbelow with reference to the accompanying drawings.
In Figure 2, the reference letter A represents a rotating assembly of a circuit installed in the upside rotary cylinder of the head drum, B represents a fixed assembly of a circuit of the downside stationary cylinder and C represents a circuit assembly. Rotating assembly A includes a pair of standard (or standard play) recording and reproducing heads SPI and SP2, a pair of long-term (or extended play) recording and reproducing heads EPI and EP2, a pair of hi-fi recording and reproducing heads HFI and HF2 and an erasing head FE. Rotating assembly A further includes the respective primary 5 windings Nil, N21 and N31 of first, second and third rotary transformers TI, T2 and T3. The standard and long-term recording and reproducing heads SPi, SP2, EP1 and EP2 are connected to primary winding NI 1 through a first signal processing circuit 100. The hi-fi recording and reproducing heads HFI and HF2 are connected to primary winding N21 through second and third signal processing circuits 200 and 300. The erasing head FE is connected to primary winding N31 through a first switch SWi. Control signal generating circuit 400 connected to the first winding N31 generates control signals Cl to C8 by detecting a logic signal modulated to an erasing signal and decoding the detected logic signal. Control signals Cl to C8 are a head switching pulse signal C6, standard and long-term select control signal C4, standard recording control signal C7, longterm recording control signal CS, hi-fi head switching pulse signal C3, hi-fi recording control signal C2, erasing control signal Cl and screen detecting control signal C8. Power supply circuit 500 having a rectifier 510 and a capacitor 520, connected to primary winding N31 supplies 20 an operating power voltage to the respective circuits by rectifying the erasing signal and smoothing the rectified signal.
First signal processing circuit 100 includes reproducing amplifiers 102, 104, 106 and 108 for amplifying the reproducing signal picked up from the respective heads SPI, SP2. EPI and EP2. a first head switch 110 for switching a pair of standard recording and reproducing heads SPi and SP2 in response to head switching pulse signal C6, a second head switch 112 for switching the pair of long-term recording and reproducing heads EPi and EP2 in response to head switching pulse signal C6, a comparator 114 for comparing the outputs of first and second head switches 110 and 112, a signal select switch 116 for selecting the output signal of the comparator 114 and the standard/long-term select control signal C4 in response to screen detecting control signal C8, a head select switch 118 for selecting the first and second head switches 110 and 112 in response to the output signals of the signal select switch 116 and connecting the selected head to primary winding of first rotary transformer Ti. a pair of first recording amplifiers 120 and 122 for amplifying the recording signal from the primary winding Nil in response to standard recording control signal C7 and supplying the amplified signals to standard recording and reproducing heads SPI and SP2, and a pair of second recording amplifiers 124 and 126 for amplifying the recording signal from primary winding Nil in response to a longterm recording control signal CS and supplying the amplified signals to long-term recording and reproducing heads EPI and EP2.
The second signal processing circuit 200 includes reproducing amplifiers 202 and 204 for amplifying the reproducing signal picked up from hi-fi heads HFI and HF2, a third head switch 206 for switching hi-fi heads HFi and HF2 in response to a hi-fi head switching pulse signal C3, and recording amplifiers 208 and 210 for amplifying the hi-fi recording signal in response to the hi-fi recording control signal C2 and supplying the amplified signals to hi-fi heads HFi and HF2.
The third signal processing circuit 300 includes a signal select switch 302 for selecting either the output signal from second signal processing circuit 200 and an erasing signal from primary winding N31 in response to screen detecting control signal C8 and supplying the selected signal to primary winding N21, and a second switch 304 which is connected between primary winding N31 and the erasing signal input terminal of signal select switch 302 and is switched in response to the output of comparator 114. Here, Ri and R2 represent resistances and CI represents a capacitor.
Secondary windings N12, N22 and N32 of the first, second and third rotary transformers Ti. T2 and T3 are mounted on the downside stationary cylinder of the head drum in correspondence with primary windings Ni i, N21 and N31 mounted on the upside rotary cylinder.
Circuit assembly C includes a video processor 600, an audio processor 700, a colour phase control signal generator 800, a modulation signal generator 900. a system controller 1000 and a servo circuit 1100.
Video processor 600 is connected to secondary winding N12 of first rotary transformer Ti. When a reproducing video signal is processed, a video signal is generated in a reproducing processor 602. Also, when a video signal is input, a recording video signal is generated in a recording processor 604 and supplied to secondary winding Ni2 of first rotary transformer Ti through a first switching circuit 606. Also. at the time of screen detecting reproduction, video processor 600 receives a colour phase control signal CP and controls the phase of the reproduced colour signal. Audio processor 700 receives an input hi-fi audio signal, supplies the received signal to secondary winding N22 of second rotary transformer T2. processes the reproducing hi-fi audio signal from secondary winding N22 and outputs the hi-fi audio signal. Colour phase control signal generator 800 receives a screen detecting control signal Xl, a standard/long-term select control signal X2 and a head switching pulse signal X3. Colour phase control signal generator 800 also receives signal from secondary winding N22 of second rotary transformer T2 at the time of screen detection, and generates colour phase control signal CP to be supplied to video processor 600. Servo circuit 1100 controls the rotation of a head drum and the transmission speed and phase of a magnetic tape and generates head switching pulse signal X3. System controller 1000 generates screen detecting control signal Xi, standard/long-term select control signal X2 and a mute control signal X4, enables the colour phase control signal generator 800 at screen detecting mode, supplies mute control signal X4 to audio processor 700 and generates a system control data signal CD consisting of control signals for standard/long-term selection, standard recording, long term recording, hi-fi recording, erasing and screen detection. Modulation signal generator 900 receives head switching pulse signal X3 and system control data signal CD and supplies a modulation signal generated by modulating to the erasing signal to secondary winding N32 of third rotary transformer T3 through a second switching circuit 902.
In Figure 3 which is a detailed circuit diagram of the modulation signal generator shown in Figure 2, modulation signal generator 900 includes a logic signal generator 904 for generating a logic signal LS by receiving control data signal CD supplied from system control circuit 1000, a first select switch 906 for selecting head switching pulse signal X3 or the logic signal LS supplied from servo circuit 1100 in response to a logic timing signal TS generated by logical signal generator 904, an oscillator 908 for generating erasing signal of a predetermined frequency, a first frequency divider 910 for generating a first frequency-divided signal DS I which is a signal frequency-dividing the erasing si nal ES by a first predetermined frequency I /in, a second frequency divider 9 912 for generating a second frequency-divided signal DS2 which is a signal frequency-dividing the erasing signal ES by a second predetermined frequency I/n, a second select switch 914 for selecting the first or second frequency signals DSI and DS2 in response to the output signal of the first select switch 906, a mixer 916 for mixing the erasing signal ES and the output signal of the second select switch 914. and a current amplifier 918 for current-amplifying and supplying the output signal of the mixer 916 as a modulation signal to secondary winding N32 of the third rotary transformer T3 via second switching circuit 902. Here, R3 and R4 represent resistances. Referring to Figures 4A to 4D, in the present embodiment of the invention, a predetermined period P of head switching pulse signal X3 is gated in logic timing signal TS, logic signal LS composed of a control signal is modulated in the period P of the gated head switching pulse signal and first and second frequency-divided signals DSI and DS2 are switched to head switching pulse which is modulated to logic signal LS, thereby selecting first frequencydivided signal DSi in a high period and second frequency-divided signal DS2 in a low period. Thereafter, a composite frequency signal is sent to mixer 916 and therein loaded onto the erasing signal ES, to be supplied to current amplifier 918 as a modulated erasing signal MS which is amplified at a predetermined gain and supplied as modulation signal to secondary winding N32 of third rotary transformer T3 through second switching circuit 902.
Accordingly, the modulation signal has the frequency characteristics as shown in Figure 5. Here, current amplifier 918 amplifies the current enough to use for operating current Vcc of rotary section A.
Referring to Figure 6, control signal generator 400 of the present embodiment of the invention includes a first bandpass filter 402 for passing only frequency component ES/m of first frequency-divided signal DSI from the modulation signal transmitted to primary winding N31 of third rotary transformer T3, a second bandpass filter 404 for passing only frequency component ES/n of second frequency-divided signal DS2 from the modulation signal, a first envelope detector 406 for detecting the envelope of the output signal from first band pass filter 402, a second envelope detector 408 for detecting the envelope of the output signal from second bandpass filter 404, a comparator 410 for comparing output signals of the first and second envelope detectors 406 and 408, and a decoding circuit 412 for generating hi fi head switching pulse signal C3 and head switching pulse signal C6 by receiving the output of comparator 410 and generating standardllong-time select control signal C4, standard recording control signal C7, long-term recording control signal CS, hi-fi recording control signal C2, erasing control signal Cl and screen detecting control signal C8 by decoding the logic signal.
That is to say, control signal generating circuit 400 detects the components of the first and second frequency-divided signals from the modulation signal and compares the amplitude of the detected two signals, thereby demodulating the head switching signal and logic signal. decoding the demodulated logic signal and generating a control signal.
Colour phase control signal generator 800, as shown in Figure 7, is enabled in a screen detecting mode in response to screen detecting control signal Xi and includes an envelope detector 810 for detecting envelope by receiving signal Yi transmitted to secondary winding N22 of second rotary transformer T2, a wave shaper 820 for wave-shaping the output signal of envelope detector 810 and a logic synthesis circuit 830 for logically synthesizing wave-shaped signal Y2, head switching pulse signal X3 suppjied from servo circuit 1100 and standardllong-term select control signal X2 supplied from system control circuit 1000 and generating colour phase control signal CP. The logic synthesis circuit 830 has a first "or else" circuit EORI.
for logically synthesizing the wave-shaped signal Y2 and standard/Ion term 9 - 19select control signal X2 and a second "or else" circuit E0R2 for logically synthesizing output of the first "or else" circuit EORI and head switching pulse signal X3 and generating colour phase control signal CP. In other words, in accordance with the setting of a standard mode or long-term mode, head switching information depending on the head selected by first signal processing circuit 100 is generated as a colour phase control signal CP at the time of detecting the screen. Since second longterm recording and reproducing head SP2 is placed adjacent to first standard recording and reproducing head SPi and first long-term recording and reproducing head EPI is placed adjacent to second standard recording and reproducing head SP2, on the head drum, if a head other than for a recording mode is selected, the phase of head switching pulse signal X3 should be inverted.
Next, a description of function and effect of the illustrated embodiment of the present invention will be given. In the illustrated device, the output of oscillator 908 of modulation signal generator 900 is transmitted to power supply circuit 500 of rotating assembly A through third rotary transformer T3 and the transmitted AC (alternating current)- oscillated signal is rectified, smoothed and generated as DC (direct current)-operating power voltage VCC. The operating power voltages necessary for the respective circuits of rotating assembly A are thus supplied. Therefore, according to the illustrated embodiment of thepresent invention, a continuous power supply is possible, thereby diminishing and simplifying the configuration of power supply circuit 500 of rotating assembly A.
Thus, when the standard recording mode is selected in the state that power is supplied, a mode control signal is generated as a standard recording control signal C7 through system controller 1000, modulation signal generator 900, third rotary transformer T3 and control signal generator 400, which enables first recording amplifiers 120 and 122. Similarly, hi-fi recording control signal C2 is also transmitted to enable recording amplifiers 208 and 210 of second signal processor 200. The video signal is supplied to standard recording and reproducing heads SPi and SP2 through recording processor 604, first switching circuit 606, first rotary transformer T I and first recording amplifiers 120 and 122. The audio signal is supplied to hi-fi recording and reproducing heads HFI and HF2 through audio recording and reproducing circuit 700, second rotary transformer T2, select switch 302 of third signal processor 300 and recording amplifiers 208 and 210 of second signal processor 200. Meanwhile, during standard reproduction, standard/long- term select control signal C4 is transmitted in the same manner to control first head select switch 118 through first select switch 116 and select first head switch 110. The signals picked up from standard recording and reproducing heads 15 SP1 and SP2 are generated as video signals through first reproducing amplifiers 102 and 104. first head switch I 10, head select switch 118, first rotary transformer TI and reproducing processor 602 and the signals picked up from hi-fi heads HFI and HF2 are generated as audio signals through reproducing amplifiers 202 and 204, head switch 206, select switch 302, 20 second rotary transformer T2 and audio recording and reproducing processor 700. Head switching pulse signals C6 and C3 which switch head switches 110, 112 and 206 during reproduction are transmitted to the head switches 110, 112 and 206 as a switching control signal through servo circuit 1100, modulation signal generator 900, third rotary transformer T3 and control 15 signal generator 400.
During long-term recording or reproducing, the long-term mode control signal is transmitted in the same manner to control second recording 1 -)l - amplifiers 124 and 126 and head select switch 116. Therefore, when recording and/or reproducing the video signal, since the standard mode and long-term mode both transmit signals between rotating assembly A and fixed assembly B through first rotary transformer TI, the number of rotary transformers can be reduced to less than that of the heads.
During erasing. erasing control signal Cl is transmitted to rotating assembly A in the same manner through third rotary transformer T3 to turn erasing switch SWi on. and the erasing signal is thus transmitted to erasing head FE through erasing switch SWi.
During screen detection, screen detecting control signal CS is transmitted to rotating assembly A to control signal select switches 116 and 302, which selects the output signal of comparator 114, and is switched to select second switch 304. Also, colour phase control signal generator 800 is enabled by screen detecting control signal Xi supplied from system controller 1000. The signals picked up from the two pairs of heads SPI, SP2, EPI and EP2 are input to comparator 114 through head switches 110 and 112, and the output signal of comparator 114 is supplied as the switching control signal of head select switch 118 through signal select switch 116. At the same time, output signal of comparator 114 is supplied as the switching control signal of second switch 304. Thus, since the signals picked up by heads SPI, SP2, EPI and EP2 are compared mutually and the component of signals which picked up through a head having the same azimuth angle as that of recording mode while scanning the current tape is at its greatest, the signal picked up by this head is selected from head select switch 118 and supplied to first rotary transformer TI. Also. at this time, second switch 304 is on/off- controlled by the output signal of comparator 114 in order to transmit an automatic head switching signal to circuit assembly C, thereby supplying the erasing signal to second rotary transformer T2 through signal select switch 302 intermittently. The intermittent erasing signal transmitted through second rotary transformer T2 is input to colour phase control signal generator 800 and generated as colour phase control signal CP according to head switching signal X3 and standard/long-term select control signal X2. The colour phase control signal CP is supplied to reproducing processor 602. Reproducing processor 602 processes the reproducing video signal supplied through first rotary transformer T1 according to the colour phase control signal CP and generates a screen detecting video signal.
In the above-described example of the present invention, a signal processor is installed within the upside cylinder of the head drum, the erasing signal, head switching pulse signal and control signal are modulated and transmitted to the circuit of the rotating assembly, the operating power is obtained by rectifying and smoothing the modulation signal, the head switching pulse signal and control signal are detected from the modulation signal, and plural heads are selectively connected to a rotary transformer for recording and reproducing a signal, thereby utilizing one rotary transformer instead of plural heads. Therefore, there is no need to increase the number of rotary transformers depending on the increase of the number of beads, and thus, only two or three rotary transformers for the video and erasing signals or for the video, audio and erasing signals are necessary. In contrast to the respective seven or nine rotary transformers for 7- or 9-head type VTRs that are conventionally installed on the head drum in a concentric circular pattern, the illustrated embodiment of the present invention uses only two or three rotary transformers. Thus, the winding of the rotary transformers are mounted easily in a concentric circular pattern on a plane. Also, since the operating power signal is transmitted continuously through an erasing rotary transformer, it is not necessary to amplif the current greatly and the power supply circuit of the rotating assembly can be simply constructed by means of a diode for rectifying and a capacitor for smoothing, thereby diminishing installation space.
The present invention is not limited to the above-described embodiment, but various modifications and variations can be made by those skilled in the art within the scope of the present invention.
The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.
All of the features disclosed in this specification (including any accompanying claims. abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.
Each feature disclosed in this specification (including any accompanying claims. abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus. unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
-24 The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
Claims (12)
1. An apparatus for recording and reproducing an information signal to and from magnetic tape, comprising:
a rotatable rotating assembly; a fixed assembly., a plurality of recording and reproducing heads mounted on said rotating assembly for recording and reproducing the information signal to and from said magnetic tape; an erasing head mounted on said rotating assembly for erasing the information signal recorded to said magnetic tape; first and second rotary transformers whose primary windings are mounted on said rotating assembly and whose secondary windings are mounted on said fixed assembly; 1) 1-0 2 control signal generating means mounted on said rotating assembly and connected to the primary winding of said second rotary transformer for generating switching control signals; first signal processing means mounted on said rotating assembly and connected between said plural recording and reproducing heads and the primary winding of said first rotary transformer for processing an information signal in response to said switching control signals, switching means connected between said erasing head and primary winding of said second rotary transformer for being switch-controlled in response to said switching control signals; recording and reproducing processing means connected to the secondary winding of said first rotary transformer for processing the information signal; modulation signal generating means connected to the secondary winding of said second rotary transformer for modulating an erasing signal and control signal and supplying the modulated signal to the secondary winding of said second rotary transformer; and power supply means mounted on said rotating assembly and connected to the primary winding of said second rotary transformer for supplying operating power voltage to the respective circuit means of the rotating assembly.
2. A recording and reproducing apparatus as claimed in claim 1, wherein 20 said first signal processing means includes amplifiers for amplifying the reproduced information signal.
3. A recording and reproducing apparatus as claimed in claim 1 or 2, wherein said modulation signal generating means comprises:
an oscillator for generating a predetermined first frequency signal as an erasing signal.
first frequency-dividing means for frequency- dividing said first frequency signal into a second frequency signal; second frequency-dividing means for frequency-dividing said first frequency signal into a third frequency signal; selecting means for selecting said second and third frequency signals in response to said control signal, and a mixer for modulating said first frequency signal with the signal selected from said selecting means and transmitting the modulated signal to the secondary winding of said second rotary transformer.
4. A recording and reproducing apparatus as claimed in claim 3, wherein 15 said control signal generating means comprises:
first and second filtering means for filtering a component of said second and third frequency signals from the modulated signal transmitted through said second rotary transformer, comparing means for comparing the detected signals of said first and second filtering means and demodulating said control signal; and decoding means for decoding said demodulated control signal and generating said switching control signals.
5. A recording and reproducing apparatus as claimed in claim 3 or 4, wherein said power supply means comprises:
a rectifier for rectifying said transmitted and modulated signal; and a capacitor for generating a power voltage by smoothing said rectified signal.
6. An apparatus for recording and reproducing video and audio information signals to and from magnetic tape. comprising:
a rotatable rotating assembly; a fixed assembly:
a pair of standard recording and reproducing heads and a pair of longterm recording and reproducing heads mounted on said rotating assembly for recording and reproducing the video information signal to and from said magnetic tape:
a pair of audio recording and reproducing heads mounted on said rotating assembly for recording and reproducing the audio information signal to and from said magnetic tape.
an erasing head mounted on said rotating assembly for erasing the information signals recorded to said magnetic tape; first, second and third transformers of which primary windings are mounted on said rotating assembly and secondary windings are mounted on said fixed assembly; - 29 control signal generating means mounted on said rotating assembly and connected to the primary winding of said third rotary transformer for generating switching control signals; first signal processing means mounted on said rotating assembly and connected between said two pairs of video recording and reproducing heads and the primary winding of said first rotary transformer for selecting a corresponding recording and reproducing head among said two pairs of recording and reproducing heads and processing the video information signal in response to said switching control signals:
second signal processing means connected between said pair of audio recording and reproducing beads and the primary winding of said second rotary transformer for processing the audio information signal in response to said switching control signals; switching means connected between said erasing head and the primary winding of said third rotary transformer for being switching-controlled in response to said switching control signals; video processing means connected to the secondary winding of said first rotary transformer for processing the video information signal, audio processing means connected to the secondary winding of said second rotary transformer for processing the audio information signal; modulation signal generating means connected to the secondary winding of said third rotary transformer for modulating the erasing signal with the control signal and supplying the modulated signal to the secondary winding of said third rotary transformer; and power supply means mounted on said rotating assembly and connected to the primary winding of said third rotary transformer for supplying operating power voltage to the respective circuit means of said rotating assembly.
7. A recording and reproducing apparatus as claimed in claim 6, wherein said first signal processing means comprises:
a plurality of amplifiers for amplifying the reproducing signal picked up from the respective heads; is a plurality of head switching means for selecting said respective pair of heads; means; a comparator for comparing the outputs of said plural head switching first switching means for selecting recording select switching control signal and output signals of said comparator in response to said switching control signal, second switching means for selecting said plural head switching means in response to the output signal of said first switching means, third switching means for switching the modulated signal transmitted to the primary winding of said third rotary transformer in response to output signal of said first switching means, a fourth switching means for selecting the output signals of said third switching means and said second signal processing means and connecting the selected signal to the primary winding of said second rotary transformer in response to said switching control signals; and a plurality of recording amplifiers for amplifying the signal transmitted to the primary winding of said first rotary transformer and supplying to said respective heads in response to said switching control signals.
8. A recording and reproducing apparatus as claimed in claim 7, wherein 15 said video processing means comprises:
a reproducing processing unit connected to the secondary winding of said first rotary transformer for processing and outputting the reproduced video signal, and controlling the phase of a reproduced colour signal by receiving a colour phase control signal during reproduction; a recording processing unit for receiving a video signal, and generating a recording video signal to be supplied to the secondary winding of said first rotary transformer through said first switching means, and colour phase control signal generating means enabled in response to a screen detecting control signal for generating said colour phase control signal by inputting the signal transmitted to the secondary winding of said second rotary transformer and logically synthesizing that signal with the head switching pulse signal and a standard/long-term select control signal.
9. A recording and reproducing apparatus as claimed in claim 8, wherein 5 said colour phase control signal generating means comprises:
an envelope detector for detecting an envelope by receiving the signal transmitted to the secondary winding of said second rotary transformer; a wave shaper for wave-shaping the output signal of said envelope detector; and a logic synthesis circuit for generating said colour phase control signal by logically synthesizing said wave-shaped signal with said head switching pulse signal and said standard/long-term select control signal.
10. A recording and reproducing apparatus substantially as hereinbefore described with reference to Figures 2 to 8 of the accompanying drawings.
11. A recording and/or reproducing apparatus having a plurality of recording and/or reproducing heads mounted on a common drum, a first transformer for coupling signals between said drum and a part with respect to which the drum is arranged to rotate, switching means for switching signals between said heads and said first transformer, and a second transformer 25 arranged to couple power and/or control signals between said drum and part.
12. A recording and/or reproducing apparatus according to claim 11, I'D further comprising any one or more of the features disclosed in the accompanying specification, claims, abstract and/or drawings, in any combination.
1
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019920021418A KR940008156B1 (en) | 1992-11-14 | 1992-11-14 | Adhesive method for wigs |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9322503D0 GB9322503D0 (en) | 1993-12-22 |
| GB2272100A true GB2272100A (en) | 1994-05-04 |
| GB2272100B GB2272100B (en) | 1996-08-21 |
Family
ID=19343154
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9322503A Expired - Fee Related GB2272100B (en) | 1992-11-14 | 1993-11-01 | Recording and reproducing apparatus |
Country Status (3)
| Country | Link |
|---|---|
| KR (1) | KR940008156B1 (en) |
| DE (1) | DE4336686C2 (en) |
| GB (1) | GB2272100B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2326756A (en) * | 1997-06-06 | 1998-12-30 | Sony Corp | Low-noise power supply arrangement for a rotary head amplifier |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3866831B2 (en) * | 1997-05-14 | 2007-01-10 | 株式会社アデランス | Wig fastening member, method for attaching wig fastening member to wig base material, and method for fastening wig |
| KR20030072134A (en) * | 2002-03-05 | 2003-09-13 | 김찬월 | method for cutting false hair |
| JP4256873B2 (en) * | 2003-07-28 | 2009-04-22 | 株式会社アデランスホールディングス | Double-sided adhesive tape and wig using the same |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2191327A (en) * | 1986-05-14 | 1987-12-09 | Mitsumi Electric Co Ltd | Drum assembly for a magnetic recording and reproducing apparatus |
| US4985785A (en) * | 1985-11-11 | 1991-01-15 | Canon Kabushiki Kaisha | Rotary head type reproducing apparatus |
| EP0510926A2 (en) * | 1991-04-26 | 1992-10-28 | Matsushita Electric Industrial Co., Ltd. | Rotary transformer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4605974A (en) * | 1982-11-24 | 1986-08-12 | Matsushita Electric Industrial Co., Ltd. | Magnetic recording and reproducing apparatus |
-
1992
- 1992-11-14 KR KR1019920021418A patent/KR940008156B1/en not_active IP Right Cessation
-
1993
- 1993-10-27 DE DE4336686A patent/DE4336686C2/en not_active Expired - Fee Related
- 1993-11-01 GB GB9322503A patent/GB2272100B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4985785A (en) * | 1985-11-11 | 1991-01-15 | Canon Kabushiki Kaisha | Rotary head type reproducing apparatus |
| GB2191327A (en) * | 1986-05-14 | 1987-12-09 | Mitsumi Electric Co Ltd | Drum assembly for a magnetic recording and reproducing apparatus |
| EP0510926A2 (en) * | 1991-04-26 | 1992-10-28 | Matsushita Electric Industrial Co., Ltd. | Rotary transformer |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2326756A (en) * | 1997-06-06 | 1998-12-30 | Sony Corp | Low-noise power supply arrangement for a rotary head amplifier |
| GB2326756B (en) * | 1997-06-06 | 1999-06-30 | Sony Corp | Signal reproduction apparatus and method |
| US6175461B1 (en) | 1997-06-06 | 2001-01-16 | Sony Corporation | Rotary head block with rotary transformer having separate channels for power signal and playback signal |
Also Published As
| Publication number | Publication date |
|---|---|
| KR940008156B1 (en) | 1994-09-07 |
| KR940010946A (en) | 1994-06-20 |
| GB2272100B (en) | 1996-08-21 |
| DE4336686A1 (en) | 1994-05-05 |
| GB9322503D0 (en) | 1993-12-22 |
| DE4336686C2 (en) | 2001-03-08 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20101101 |