KR19980067951A - How to use head - Google Patents

Abstract

The present invention calculates the number of pulses output from the pulse generator coupled to the drum servo by counting the number of pulses output from the pulse generator coupled to the drum servo, and accumulates and stores them so that they can be output on-screen as needed. The present invention relates to a method of displaying the use time of a head which can be utilized for troubleshooting.

In the existing VSI, the tape counter is used to display only the current playback time or recording progress time, but the life of the head can be predicted because it does not have information on the total cumulative usage time of the head or its management function. The total hours of use were unknown.

A feature of the present invention is that the head usage time associated with tape playback or recording is accumulated and managed on the basis of the number of rotation pulses of the drum so that the total usage time can be displayed on the television screen through an on-screen method whenever necessary.

The present invention can accurately check the parts replacement time according to the durability of the various components with reference to the use time of the V-Sial and the effect can be utilized for A / S.

Description

How to use head

The present invention accumulates and stores the tape count value of VSI, and outputs it on-screen as needed. It is about.

Figure 1 shows a schematic circuit configuration of a general VSI system control system.

As referred to herein, the system controller 10 includes a timer, a channel preset unit 12, and a video that transmit channel information and time information to the tuner unit 11 and the display 13 for channel selection and time output. And a video unit 20 and an audio unit 19, a servo unit 18, a key input and a remote control unit 21, 17, an operation unit 16, and a sensor unit 15 for processing audio signals. And a mechanism for controlling the mechanism portion 14.

This control system controls the operation of the tuner, A / V signal system, servo, and mechanical parts in order to record, play, rewind, etc., and also monitors the operating state of VSI by various sensors. If this occurs, the tape running is immediately stopped and controlled to prevent the tape or the mechanism from being damaged.

The system controller 10 includes a microprocessor for comprehensively determining and commanding various sensors and various information on the conditions of each part, and the main operations thereof are loading and unloading of cassettes (eject) and tape. Controls loading, unloading, recording, playback, fast forward, rewind, special playback (speed playback, etc.), and also detects loosening of tapes, tape end and start sensors, and rotation detection tapes on video heads and take-up reels. To prevent damage to the tape and the mechanism accordingly.

The timer and channel preset unit 12 has a built-in microcomputer for timer, and the remaining time of the tape according to the standard mode and the long time mode is electronically counted and displayed on the display 13 during recording and playback.

Such an electronic counter generates a reel pulse signal corresponding to a rotational speed by installing a resin magnet on a supply side and a winding side of a tape reel and a hall element on a reel stage. The reel pulse signal is input to the timer microcomputer to calculate the remaining tape time based on the information about the standard / long time mode and the thin tape / thick tape.

In other words, the reel rotation speed rotates slowly when the amount of tape wound on the reel is high and rotates rapidly when the amount of tape is low. It can be calculated.

On the other hand, the system controller 10 tunes the desired channel by electronic tuning of the tuner unit 11 through the timer and channel preset unit 12.

The video unit 20 and the audio unit 19 are controlled by a system control to process a video signal and an audio signal for reproduction or recording.

The servo unit 18 detects a control amount such as the rotational speed as a comparison signal from a control target such as a motor so as to accurately control the rotational speed and rotational phase of the head, the tape traveling speed, and the like, and the servo unit 18 generates a clean video signal. Accurately control the head rotation speed, rotation phase and tape speed for recording and playback. The basic control method detects a control amount related to the rotational speed or the like from a control target such as a motor, compares it with a reference value, and corrects the error value so that the tape running speed and the like can be constantly controlled.

The key input unit 21 transmits a keying signal from the key switch installed on the front panel of the VSI to the system controller 10.

The remote controller 17 transmits a remote control signal to the system controller 10.

The operation unit 16 controls the operation indicator lamp by the system controller 10 and transmits data on the tape speed (LP / SP) selection and operation switch and timer switch to the system controller 10.

The sensor unit 15 transmits a sensing signal collected from a condensation sensor, a cassette-in sensor, a tape end and start sensor, a recording tap sensor, a loading and unloading sensor, etc., to prevent dew formation of the drum to the system controller 10. do.

The mechanism unit 14 controls the reel motor and the loading motor, the pinch and the brake solenoid.

The VSI, which is operated by such a control system, is informed to the user of the operation time of the VSI via the main function through the remaining tape detection. This usage time information is very useful for tape playback and recording management.

However, since the remaining function can only grasp the recording and playback time for one tape, it is not possible to know the total usage time of the head for predicting the life of VSI.

The information on the cumulative usage time of VSIAL will be very useful for VSI's post-warranty or the determination of the life of VSIAL itself.

An object of the present invention is to calculate the number of pulses output from the pulse generator coupled to the drum servo, and to accumulate and store them in the on-screen manner to output the life of the VSI. An object of the present invention is to provide a method of displaying the use time of a head, which can be used for prediction and troubleshooting.

A feature of the method for displaying the head usage time according to the present invention is to count the head pulse time associated with tape playback or recording by counting the output pulses of the drum rotation pulse generator coupled to the drum. And then, when the VSI is turned off, accumulating the head usage time calculated up to that point in the previous data and storing it in the memory; and using the head stored in the memory according to the head total usage time output key input by the user. And displaying the time data on the television screen through the on-screen method.

1 is a circuit block diagram of a typical BC control system.

2 is a block diagram of a drum pulse count signal processing circuit for implementing the present invention.

3 is a flowchart illustrating the operation of the present invention.

* Description of the symbols for the main parts of the drawings *

32: microcomputer 33: key input unit

34: indicator 35: OSD

37: drum motor 42: pulse generator

43: counter 44: memory

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Since VSIal records and reproduces video signals by rotating head method, it requires servo to precisely control head rotation speed, phase, and tape running speed for clear screen recording and playback.

The servo refers to controlling a control target by detecting a control amount related to the rotational speed or the like as a comparison signal from a control target such as a motor, processing it in a comparison error detection circuit, amplifying the output error signal.

In VSI, a video signal of one field corresponding to 1/60 second is recorded on one video track.

Therefore, the servo is synchronized with the video head and the tape so that the vertical blanking period on the tape is recorded at the beginning of the track while the video head is rotated at 1/2 of 60Hz, the vertical synchronization frequency of the input video signal. To control the positional relationship.

In addition, the servo records the control signal necessary as a reference at the time of reproduction on the control track, and serves to drive the tape at a constant speed.

The position of the control signal indicates the position of the recording signal at the time of reproduction.

That is, since the distance between the position of the control signal and the video track is determined by the standard, the rotating head can trace and play the track as in the case of recording based on the control signal.

The control signal is recorded at one ratio for two video tracks because the azimuth recording is done with two video heads, so the video track recorded with the first channel head must be traced to the corresponding head. One control for the rotation.

The operation of the playback servo is to accurately trace the head on the recorded video track.

Since the video tracks are recorded at intervals of about 20-58 μm with no gaps, it is not easy for the head to trace seamlessly on this video track.

Therefore, at the time of reproduction, the control signal recorded on the control track is reproduced as a reference signal to control the rotational phase of the video head so that the positional relationship between the tape and the head is the same as at the time of recording.

In the drum servo, as a reference signal, a 30 Hz signal obtained by half counting the vertical synchronizing signal of the input video signal is used for recording, and a control signal recorded in the control track is used during playback.

At the time of recording, a 60 Hz vertical synchronization signal is detected from the video signal to be recorded and counted down to 1/2 as a mono multi to generate a 30 Hz reference signal.

On the other hand, the pulse generator detects a pulse representing the rotational phase of the video head and applies it to a reference signal of 30 Hz and a phase comparison circuit to detect the deviation of the video rotational speed as an error signal.

When the error signal is applied to the control circuit, the control circuit applies an electromagnetic brake to the rotating head in accordance with the error signal, so that the rotating head always rotates 30 seconds per second in synchronization with the frequency signal of 1/2 of the vertical synchronization signal and at the same time rotates the phase. The position of the start on the tape is also controlled to start in the vertical blanking period.

At the same time, since the reference signal of 30 Hz is used as a reference during reproduction, it is recorded on the control track by the control head.

At the time of reproduction, the control signal reproduced by the control head is applied to the phase comparator based on the reference.

The comparison signal side applies the pulse of the pulse generator to the phase comparison circuit as in the case of writing.

In this case, the rotational speed of the capstan is always constant due to the characteristics of the synchronous motor, and since the tape traveling speed does not change during recording and reproduction, the control signal recorded in the fixed head can be used as a reference signal as it is during reproduction.

The deviation of the rotational speed of the head is detected as an error signal by comparing the reference signal with the pulse of the pulse generator.

Since the rotational head is set slightly faster than 30 Hz as in the recording, the control circuit applies an electromagnetic brake according to the error circuit so that the rotational speed and the rotational phase of the rotating head are set to be the same as in the recording.

As a result, the video head can trace a narrow video track of about 28-58 mu m as in recording.

Fig. 2 is a circuit diagram of the main part of VSI for implementing the present invention.

As referred to herein, the video signal is input to the sync separator 30. In this sync separator, a 60 Hz sync signal is separated.

The synchronous signal separated by the synchronous separator 30 is connected to be input to the mono multi divider 31. Here, the 60 Hz sync signal is divided into 1/2 and output as a 30 Hz control signal.

The control signal thus produced is applied to the control head 39 when the changeover switches 40 and 41 are located at the recording terminal, connected to be recorded on the control track of the video tape, and the changeover switch 40.41 is located at the playback terminal. At the time of reproduction, a control pulse on the control track read by the control head 39 is input to the control amplifier 38, where the control signal is amplified and then applied to the microcomputer 32 side.

The microcomputer 32 is provided on a key input unit 33 for processing and transmitting a user key input such as a timing count using a control pulse to the microcomputer 32, and on a VSI front surface for informing a user of a count value. Display 34 and an OSD 35 for displaying the corresponding count value on-screen through the screen of the television connected to the TV.

In addition, the microcomputer 32 is connected to a control signal for controlling the head drum in accordance with the control period is processed in the drum motor speed controller 36 to be applied to the drum motor 37, the pulse generator to the drum motor 37 42 is provided so that the number of pulses obtained here is provided via the counter 43 to the microcomputer 32 having a memory 44 for storing accumulated data for the total head usage time.

Referring to Fig. 3, the VSA head using time display process of the present invention based on such control signal processing and drum pulse generation circuit is described.

When the VSI user first selects the tape playback or tape recording mode by using the key input unit 33, the microcomputer 32 controls the drum driving system and the drum motor 37 through the drum motor speed controller 36 at the same time. PWM control. This PWM control is used to precisely control the drum at 1800 RPM. When this is divided by the synchronous frequency (60Hz), a pulse signal such as a 30Hz control pulse is obtained.

Since this calculation is performed in the pulse counter 43 and input to the microcomputer 32, the V-Head head use time of the present time is calculated through the timing of 30 drum pulses being 1 second. The timing data thus calculated is read out from the memory 44 of the accumulated head use time up to the time when the VSI is turned off, or precisely, when the tape drive is turned off, and then accumulated therein and stored in the memory again.

Then, when the user inputs the head use time output key signal through the key input unit 33 to determine the life of the VSI, the microcomputer 32 displays the accumulated time data stored in the memory 44 up to that time on the display 34. Output on the screen of the television via the OSD (35).

Figure 3 shows for easy reference the implementation process of the present invention described above for reference.

As described above, the present invention processes the number of drum pulses generated in proportion to the rotational speed of the drum to count the operating time of the VSI, and then, the timing value up to the time when the VSI is off, is stored in the previously accumulated timing data. In addition, the accumulated timing data is output on the screen according to a user's key input, thereby making it possible to easily predict the life of VSI or the life of the head.

Claims (1)

In the method for calculating and displaying the head usage time of VSI, calculating the current head usage time by counting the number of rotation pulses of the drum driven during tape playback and recording, and executing the timing in pulse counts per second. Then, when the VSI is turned off, accumulating the head usage time calculated up to that point in the previous data and storing it in the memory; and the head usage time stored in the memory according to the head total usage time output key input by the user. And displaying the data on a television screen through an on-screen method.