KR0162224B1 - How to measure the tension control performance of digital VR - Google Patents

Abstract

Tension control performance measurement method of digital VRL is a method of measuring the tension performance of a running tape.At this time, the tension control is properly performed by grasping the characteristics of the tension control using an envelope detection method by a fixed head. Be aware of this. In the method of the present invention, in a tape drive system of a digital VLC deck for reproducing a magnetic recording storage medium having a track pattern configured to record an amble signal of a constant frequency for adjusting a traveling system in a predetermined section of a recording track, the amble signal The fixed heads for picking up the wheels are mounted on the D-VCR deck, and the performance of tension control can be easily measured using the above-described envelope detection method by the fixed heads. Provides the effect of reducing effort and time.

Description

How to measure the tension control performance of digital VR

1 is a configuration diagram showing an example of the structure of a deck running system of a conventional VCR for a gas.

2 is a block diagram of the fixing heads mounted on the tape path of the deck running system of FIG. 1 according to a preferred embodiment of the present invention.

3 is a diagram showing a travel relationship between a gap region of a recording medium on which an amble signal is recorded and a fixed head of FIG.

FIG. 4 is a waveform diagram showing an envelope detected by the fixed head of FIG. 3 traveling through a gap region of a recording medium, and a relationship between a phase pulse and a head switching pulse (HSW) produced using the same. FIG.

FIG. 5 is a diagram showing a track pattern in which an amble is recorded in a predetermined area on a recording medium in order to evaluate the performance of tension control in the deck driving system of FIG.

FIG. 6 shows a positional relationship in which the fixing heads shown in FIG. 2 are mounted on the recording medium of FIG.

FIG. 7 is a timing diagram showing an example of reference intervals and error tolerances between the fixed heads through an envelope reproduced by the two fixed heads of FIG. 2 and a phase pulse and a head switching pulse (HSW) generated using the same.

FIG. 8 is a diagram showing an example of data comparing, in real time, the interval between the reference interval shown in FIG. 7 and the two fixed heads actually measured.

* Explanation of symbols for main parts of the drawings

30: band brake 31: supply reel

32: tension arm 33, 35: roller impedance

34: tension spring 36, 40: guide roller

37, 39: Slantpole 38: Head drum

41: capstan 42: pinch roller

43: guide pin 44: supply reel

A, B: fixed head

The present invention relates to a method for measuring the tension performance of a traveling tape in a digital video cassette (D-VCR) system, and in particular, an envelope detection method by a fixed head. The present invention relates to a method of measuring tension control performance of a D-VCR by identifying the characteristics of tension control by using the T-VCR.

In recent years, with the transition from analog VCRs to digital VCRs, efforts have been made to reduce the size of decks and to develop high density narrow track D-VCRs. Therefore, a high frequency and constant signal (hereinafter, referred to as an amble signal) is recorded in a gap area of the recording medium, and the above-mentioned amble signal is picked up using a fixed head during reproduction, and the envelope of the picked up amble signal is used. A method of controlling the tracking operation of the D-VCR system using the values has been proposed. The tracking control method using the amble signal as described above has an advantage that the tracking operation can be smoothly performed even at double speed playback.

In addition, there is an advantage in that it is not necessary to form a control track for recording a control signal for tracking control as in the conventional VHS method, or to superimpose a pilot signal on recording data as in the ATF (Automatic Track Finding) method.

Tension control is a function to control the recording and playback function of the head faithfully by maintaining the gap between the head attached to the drum and the conveyed tape in the VCR system. It is common to solve this problem. This is because, in tension control, it is difficult to make information fed back like a drum or a capstan, it does not require high technology to be controlled by servo, and economical efficiency is inferior. However, in the conventional tension control method, since the deck is empirically constructed by repeating various experiments and calculations in order to obtain proper control performance, much effort has been consumed in carrying out the experiments and calculations.

1 is a configuration diagram showing an example of the deck driving system configuration in a conventional home VCR deck. In Fig. 1, the running sequence of the tape is as follows. First, the tape drawn out from the supply reel 11 reaches the first roller impedance 13 attached to the tension arm 12. The tape then approaches the first guide roller 15 via a second roller impedance 14 that absorbs vibrations in the tape travel direction. The first guide roller 15 serves to allow the tape to flow into the head drum 17 while maintaining a constant contact area. The tape is then drawn into the head drum 17 through a supply slot pole 16 positioned parallel to the axis of rotation of the head drum 17 at right angles to the tape advancing direction. That is, the feed slot pole 16 adjusts the inclination of the tape to be drawn parallel to the head drum (17). Then, the tape carries out the recording or reproducing operation while passing through the head drum 17. The tape passing through the head drum 17 is returned to the original tape running position while passing through the take-up slant pole 18 and the second guide roller 19. Then, the tape is sandwiched between the capstan 20 and the pinch roller 21 and conveyed to the feed reel 22 at a constant speed. At this time, between the capstan 20 and the pinch roller 21 and the receiving reel 22 is provided with a guide pin 23 for smooth transfer of the tape.

It is very important for the performance of the product that the tape running in the tape running system as described above maintains the proper tension. In the conventional tension control, when the running tape receives a tension above or below an appropriate level, the tape pushes the first roller impedance 13 of FIG. 1, and the tension arm 12 then affects the tension spring 24. Tension control of the tape was performed by configuring the deck traveling system to rotate while receiving and tighten or loosen the band brake 10. At this time, in constructing a technique for tension control as described above, a lot of efforts such as repeated experiments and measurements are required to obtain appropriate control performance. As an example, a tension measuring tape is used to measure the torque applied to the supply reel, and other components are empirically adjusting the deck running system while watching the envelope during regeneration. On the other hand, as a method of evaluating the performance of the tension control method, there is a method of evaluating by measuring the linearity of the recording track by measuring the microscope by applying a reagent by cutting the tape and measuring the microscope.

However, since the methods described above should determine the appropriate tension adjustment value through various experiments and calculations, it may take a long time and the precision may be degraded, and there is an inconvenience of repeatedly performing the experiments and calculations. .

Accordingly, an object of the present invention is to mount the fixed heads for picking up the amble signal described above on the D-VCR deck, and to measure the performance of the tension control using the above-described envelope detection method by the fixed head. In addition, the present invention provides a method of measuring the tension control performance of the D-VCR to reduce the effort and time spent in the development of a deck configured to maintain an appropriate tension.

Another object of the present invention is to provide a D-VCR deck for measuring tension control performance for achieving the above object.

In order to achieve the above object, a method of measuring tension control performance of a digital VLC according to the present invention records an amble signal of a predetermined frequency on a recording track of a magnetic recording storage medium, and picks up the above-described amble signal at the time of reproduction, thereby recording the magnetic recording medium. A method of controlling the reproduction of information recorded in the apparatus, wherein the envelope is detected from an amble signal picked up by a first and a second fixed head mounted at a predetermined position on a VCR deck in order to pick up the amble signal described above. Doing; Generating phase pulses indicating a maximum level value of the envelope for each of the first envelope detected from the first fixed head and the second envelope detected from the second fixed head; And determining a tension control performance by comparing an interval between a first phase pulse generated from the first envelope and a second phase pulse generated from the second envelope and a reference interval between two preset phase pulses.

In addition, another object of the present invention is to provide a tape driving system of a digital VD deck for reproducing a magnetic recording storage medium having a track pattern configured to record an amble signal of a constant frequency for adjusting a traveling system in a predetermined section of a recording track. A first fixing head mounted between the capstan and the guide roller on the receiving reel side to pick up the above-described amble signal; And a second fixed head mounted between the supply reel side guide roller and the impedance roller to pick up the above-described amble signal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram of the fixing heads mounted on the tape path of the deck traveling system of FIG. 1 according to a preferred embodiment of the present invention. As shown, the deck system of FIG. 2 mounts the first and second fixing heads A and B for picking up the above-described amble signal. In FIG. 2, the first fixing head A is mounted close to the capstan 41 between the guide roller 40 and the capstan 41 on the supply reel 44 side, and the second fixing head B is It is mounted between the supply roller 31 side guide roller 36 and the second impedance roller 35 to pick up the above-described amble signal. Here, the first fixing head A is mounted close to the capstan 41 that provides the driving power of the tape so as to pick up the above-described amble signal where the running displacement of the tape is not large due to the change in tension state. . On the other hand, the second fixing head B is mounted at a position where the traveling displacement of the tape is relatively large according to the change of the tension state and picks up the above-described amble signal. Therefore, when the envelope is reproduced from the amble signals picked up by the first and second fixed heads A and B, and the interval of the envelope is measured, the gap between the head and the tape can be inferred. Evaluate if it is working. A detailed description of the tension control performance measurement method described above will be made later with reference to FIGS. 7 and 8. The description of the configuration of other parts of the deck system of FIG. 2 is the same as that of FIG.

On the other hand, in order to apply the method for measuring the tension control performance of the D-VCR according to the present invention, a recording medium having a track pattern configured to record the above-described amble signal in a certain period of the recording track should be used. The description of the recording medium on which the amble signal is recorded will be described later with reference to FIG.

3 is a diagram illustrating a driving relationship between a gap area of a recording medium on which an amble signal is recorded and a fixed head of FIG. 2, and FIG. 4 is an envelope detected by the fixed head of FIG. 3 traveling through a gap area of a recording medium. This is a waveform diagram showing the relationship between the phase pulse and the head switching pulse (HSW) produced by using. As shown in Fig. 3, the width of the fixed head applied to the present invention should be set to match the width of the track pitch recording the amble signal. The fixed head picks up the above-described amble signal while driving the gap area of the recording medium in the longitudinal direction of the tape, and reproduces an envelope of the form shown in FIG. 4 (b) from the picked-up amble signal. At this time, the phase pulse as shown in FIG. 4 (c) is generated at the specific level value of the reproduced envelope and used for the capstan servo. In the case of tracking control, the time of the phase pulse is measured on the basis of the head switching pulse (HSW) as shown in Fig. 4A, and phase control using the same is performed. Here, an example of generating the above-described phase pulse at the maximum level value of the envelope waveform is shown.

FIG. 5 is a diagram illustrating a track pattern in which an amble is recorded in a predetermined area on a recording medium in order to evaluate the performance of tension control in the deck driving system of FIG. 2. FIG. 1 shows the first and second fixing heads A, which are shown in FIG. The recording pattern of the recording medium track configured to record the amble signal at the height at which B) is mounted is shown. Here, the first fixed head (A) picks up the amble signal of track A, and the second fixed head (B) picks up the amble signal recorded on track B, so that the azimuth of tracks A and B ). FIG. 6 is a view showing the positional relationship in which the fixed heads shown in FIG. 2 are mounted on the recording medium of FIG. 5. The first fixing head A is an amble signal recorded in a predetermined section of the A recording track near the capstan. The second fixing head B picks up the amble signal recorded in a predetermined section of the B recording track. At this time, the two fixed heads set the azimuth to pick up the energy of the track relatively stronger than the energy of the other track.

The tension control performance measurement method of the D-VCR of the present invention configured as described above will be described in detail.

FIG. 7 is a timing diagram showing an example of reference intervals and error tolerances between the fixed heads through an envelope reproduced by the two fixed heads of FIG. 2 and a phase pulse and a head switching pulse (HSW) generated using the same. .

First, the first and second fixing heads A and B mounted at the positions shown in FIG. 2 pick up the amble signals recorded on the tracks by traveling through the gap area of the recording medium as shown in FIG. Then, the envelope is reproduced from the picked-up amble signal. FIG. 7B is a waveform diagram showing an envelope reproduced by the first fixed head A, and FIG. 7C is a waveform diagram of an envelope reproduced by the second fixed head B. As shown in FIG. Then, a phase pulse is generated at a specific level of the reproduced envelope. 7 (d) and 7 (e) are waveform diagrams showing the shape of phase pulses generated by using the envelopes reproduced by the first and second fixed heads A and B. FIG. As shown, the above-described phase pulses become 'high' when the envelope value is maximum, and otherwise maintain 'low' level. At this time, the tension control state can be determined by measuring the interval between the phase pulse of FIG. 7 (d) and the phase pulse of FIG. 7 (e).

That is, the interval and the control range of tension control can be grasped by comparing the interval measurement value between the reference interval, which is calculated and set as an appropriate level of tension, and the phase pulse generated from the envelopes reproduced from the two fixed heads. In FIG. 7, the time corresponding to ½ of the head switching pulse (HSW) period based on the head switching pulse (HSW) of FIG. 7 (a) is shown as a reference interval. This means that during the ½ cycle of the head switching pulse (HSW), the rotating heads of the drum travel one track section, and the first and second fixed heads A and B also pick up the amble signal of the one track section to reproduce the envelope. Therefore, the two fixed heads are mounted so that the interval between the envelope regenerated by the first fixed head A and the envelope regenerated by the second fixed head B is generated by ½ of the head switching pulse (HSW) period in a proper tension state. In other words, the above-described phase pulses are used to maintain the reference interval of one track section as shown in FIG. In addition, Fig. 7 shows an error tolerance range in which the performance of tension control can be measured by the above-described method. This data is obtained by measuring the interval between the first phase pulse made using the envelope reproduced by the first fixed head A and the second phase pulse made using the envelope reproduced by the second fixed head B, and the above-mentioned reference. In comparing the intervals and identifying the tension state, it is indicated that it is impossible to determine the tension state when the difference between the data and the reference interval exceeds a predetermined range. At this time, if the operation range of the tension control exceeds one track section for one period of the head switching pulse (HSW), the capstan phase control is out of the range of the capstan phase control, and thus the meaning of the tension control is lost. The range is set according to the characteristics of the deck. FIG. 8 is a result diagram showing an example of data comparing a reference interval shown in FIG. 7 and an interval between two fixed heads measured in real time. In FIG. 8, the horizontal axis shows the real time of the measurement, and the vertical axis shows the interval between the two phase pulses measured by the above-described method. Here, when the interval measurement value between the two phase pulses exceeds the reference interval, the tension is smaller than the reference value, and when the interval measurement value is smaller than the reference interval, the tension is larger than the reference value. By performing the tension adjustment using the result chart of FIG. 8, the enormous time and effort spent in the conventional tension adjustment can be saved.

As described above, the method of measuring the tension control performance of the D-VCR according to the present invention makes it possible to easily measure the performance of the tension control by using the envelope detection method by the fixed head, thereby developing a deck configured to maintain an appropriate tension. It can reduce the effort and time spent on the system.

Claims (8)

A method of recording an amble signal of a predetermined frequency on a recording track of a magnetic recording storage medium, and picking up the amble signal at the time of reproduction to control reproduction of information recorded on the magnetic recording medium. Detecting an envelope from an amble signal picked up by a first and a second fixed head mounted at a predetermined position on the digital VCD deck for pickup; Generating phase pulses indicating a maximum level value of the envelope for each of the first envelope detected from the first fixed head and the second envelope detected from the second fixed head; And determining a tension control performance by comparing an interval between a first phase pulse generated from the first envelope and a second phase pulse generated from the second envelope and a reference interval between two preset phase pulses. Tension control performance measurement method of digital VRL. The method of claim 1, wherein the phase pulse maintains a high state when the envelope value reaches a maximum value, and maintains a low state when the envelope pulse reaches a maximum value. 3. The method of claim 2, wherein the reference interval between the first and second phase pulses is an interval when the digital VLC set is calculated in an appropriate tension state. The method of claim 3, wherein the determining of the tension control performance is such that when the interval measurement value after the first phase pulse occurs until the second phase pulse occurs exceeds the reference interval, the tension is smaller than the reference interval. And if the interval measurement value is smaller than the reference interval, determine that the tension is larger than the reference value. In the tape drive system of digital VLC deck for reproducing a magnetic recording storage medium having a track pattern configured to record an amble signal of a constant frequency for adjusting the traveling system in a certain section of a recording track, a guide roller on the capstan and supply and reel side A first fixing head mounted near the capstan between the first fixing head and the pick-up signal for picking up the amble signal; And a second fixing head mounted between the supply reel-side guide roller and the impedance roller to pick up the amble signal. 6. The tension control performance measurement of claim 5, wherein the first to second fixing heads are mounted at a predetermined height perpendicular to the length direction of the tape to travel the area where the amble signal is recorded. Dragon's Digital V Deck. 7. The digital VCD deck of claim 6, wherein the first and second fixing heads pick up the amble signal by traveling the area in which the amble signal is recorded in the length direction of the tape. 8. The digital VRC deck for measuring tension control performance as claimed in claim 7, wherein the first and second fixing heads are azimuth to pick up only the amble signal of either track of the pair of recording tracks.