JPH04332989A - Method and device for detecting hub diameter of tape reel - Google Patents

Abstract

PURPOSE:To detect the hub diameter of a tape reel irrespective of the magnitude of the hub diameter and, at the same time, to accurately display the remaining time of a tape, by coping with a difference in the hub diameter with software and finding the hub diameter by calculation. CONSTITUTION:The hub diameter of a tape reel is found by calculation by using a pulse period obtained from the rotation of a take-up side tape reel 4, rotating speed of the reel 4 from the initialization, and the speed and thickness of a tape. The abovementioned calculation is carried out by an equation, rT0=(A.v0/2pi)TT-d.nt, where, the rT0, d, TT, nT, v0, and A respectively represent the hub radius of the take-up side tape reel plus the wound thickness of the tape on the reel, thickness of the tape, pulse period of the tape reel, rotating speed of the tape reel from the initialization, tape speed, and number of poles of the tape reel. The rT0 at the starting end of the tape is regarded as equal to the hub radius.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention is applicable to tape recorders, DA
The present invention relates to a tape reel hub diameter detection method and device used in a device for detecting the traveling amount and remaining amount of tape in T-shirts, VTRs, etc.

0002

[Prior Art] In this type of device that detects the running amount and remaining amount of tape and displays the elapsed time and remaining amount time, conventionally, in order to detect the running amount of tape, the tape reel on the take-up side or the supply It is known to measure the period of a pulse train (hereinafter referred to as reel pulse) obtained in response to the rotation of a side tape reel, and to convert this measured period into the remaining amount of tape by calculation (for example, Japanese Patent Publication No. 58-197
No. 77, No. 57-143772, No. 63-21498
No. 8, No. 63-214989, No. 63-214990
(see publication).

0003

However, the conventional calculation method does not take into account the difference in the hub diameter of the tape reels used, and calculates by substituting a fixed constant for the hub diameter. However, as a practical matter, there are variations in the values (constants) due to differences in tape types and manufacturers. Additionally, if you want to use the tape for a long time in the future, you will need to take measures such as reducing the hub diameter. In such a case, tapes with different hub diameters will output incorrect data, causing errors in the display of remaining amount time, etc. Furthermore, this is also inconvenient when controlling the tape speed so as not to damage the tape at the end of the tape.

The present invention has been made to solve the above-mentioned problems, and uses software to deal with differences in the hub diameter of tape reels. The purpose of the present invention is to provide a method and device for detecting the hub diameter of a tape reel, which can detect the hub diameter without error even if the tape has a hub diameter of 1.5 mm, and can also accurately display the remaining time, etc. do.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the invention of claim 1 provides a method for adjusting the pulse period obtained by the rotation of the take-up tape reel, the number of rotations of the reel from the initial setting, and the tape speed. This is a tape reel hub diameter detection method that calculates the tape reel hub diameter using tape thickness. The invention of claim 2 performs the above calculation by calculating the radius of the tape wound on the take-up tape reel and the hub at the time of initial setting.
When T0 is the tape thickness, d is the pulse period of the take-up tape reel, TT is the rotational speed of the take-up tape reel from the initial setting, is the tape speed v0, and is the number of poles of the tape reel as A. rT0=(A・v0/2π)TT
-d・nT Using the formula, rT0 near the beginning of the tape
Let be the hub diameter. The invention according to claim 3 provides a tape reel hub in which the diameter of the tape reel hub is calculated by using the rotation period of the tape reel on the supply side at the time of initial setting, the number of rotations of the reel from the time of initial setting, the tape speed, and the tape thickness. This is a diameter detection method. In the invention of claim 4, the above calculation is performed using rS as the radius of the tape wound on the supply side tape reel and the hub, d as the tape thickness,
When the initial pulse period of the supply tape reel is TS0, the number of revolutions of the supply tape reel from the initial setting is nS, the tape speed is v0, and the number of poles of the tape reel is A,
Using the formula rS=(A·v0/2π)TS0−d·nS, let rS near the end of the tape be the hub diameter. The invention as claimed in claim 5 provides a rotation speed detection means for generating a pulse proportional to the rotation speed of the tape reel on the take-up side, and a predetermined calculation using a predetermined pulse period obtained from the rotation speed detection means. A tape reel hub diameter detecting device includes a calculation means for calculating a tape reel hub diameter, and the calculation means calculates the formula shown in claim 2. The invention as set forth in claim 6 provides a tape reel by performing a predetermined calculation using a rotation speed detection means that generates a pulse proportional to the rotation speed of the supply side tape reel and a predetermined pulse period obtained from the rotation speed detection means. 4. A tape reel hub diameter detection device comprising a calculation means for calculating a reel hub diameter, wherein the calculation means calculates the equation set forth in claim 4.

[0006]

[Operation] According to the above method and device, the pulse period obtained by the rotation of the tape reel on the take-up side or the supply side, the rotation speed of the same reel from the initial setting, the tape speed, and the tape thickness are used to calculate the Even if the tape has a hub diameter of
The hub diameter can be determined by calculation.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of a tape recorder in which the method and apparatus of the present invention are implemented. The microcomputer 1 takes in information on changes in the cycle of pulses (reel pulses) obtained by the rotation of the tape reel, calculates the hub diameter by a calculation described later, and performs the reel calculation based on the hub diameter calculated by this calculation. It has a function to calculate the remaining tape time, etc., and display it. A sensor 5 for detecting the rotation of the supply side reel 3 of the tape 2 as means for obtaining pulses corresponding to the rotation of the tape reel;
A sensor 6 for detecting rotation of a reel 4 on the take-up side (take-up side) of the tape 2 is provided. Pulse signals from the sensors 5 and 6 are waveform-shaped via amplifiers 7 and 8, and are input to the microcomputer 1. Also, each reel 3
, 4 is detected by the FG sensor 10, and this detection signal is sent to the amplifier 11 as the tape speed.
The data is input to the microcomputer 1 via. The display 12 displays the calculated remaining amount of tape, etc. The memory 13 is a storage means for storing various data and the like. A servo system for driving the tape reel is not shown. Note that the memory 13 also stores tape thickness data, and this data is also given to the microcomputer 1. In addition, the microcomputer 1 cumulatively stores the number of reel pulses, and calculates the current position based on changes, including increases and decreases, in the cumulative number of pulses even when the tape is fast forwarded or rewound. I try to do that.

FIG. 2 is a diagram schematically showing the supply side and take-up side of the tape reel, and the calculation formula for detecting the hub diameter by the microcomputer 1 will be explained below. In Figure 2, v0: tape speed d: tape thickness rh: hub radius (hub diameter) rT: radius of the tape wound on the take-up side and the hub rS: radius of the tape wound on the supply side and the hub rT0: rT at initial setting rS0: rS at initial setting TT: Reel pulse cycle on take-up side TT0: Initial reel pulse cycle on take-up side TS: Reel pulse cycle on supply side TS0: Initial reel pulse cycle on supply side A: Number of reel poles nT: Number of rotations of the take-up side reel from the time of initial setting (number of TT pulses counted A times) nS: Number of rotations of the supply side reel from the time of initial setting (number of TS pulses counted A)
(number of times counted).

First, considering only the take-up reel, the following equation holds true. rT = rT0+d・nT

…■ Also, 2πrT = A・v
0 ・TT A・v
0 Therefore, rT =──────TT

…■ 2
From π ■, ■ rT0=(A・v0/2π)TT −d・n
T
...■Here, if we rewind the tape to the starting end and set the various parameters at that position as initial values, rT0 is the hub diameter rh
is equivalent to Therefore, the hub diameter can be determined using the above equation (2). That is, the hub diameter can be determined by substituting the reel pulse period etc. obtained when the reel rotates several times after the tape starts running from the starting end into the above equation (2).

Similarly, in the case of the supply side reel,
rS = rS0-d・nS

…■ A・
v0 rS0 =──────TS0

…■ 2π ■,■ According to the formula, A・v0 rS =──────TS0−d・nS

...■ 2π Here, the tape is run at a constant speed of v0 near the end, and the value of rS at the moment when it is wound up to the tape end position is equivalent to the hub diameter rh. Therefore, at this time, the hub diameter is determined by the above equation (2). By storing the data once obtained by the formula (■) or (■) above in the memory 13, from then on, even if the tape is run from the middle, the reel calculation described later can be performed using that data, ensuring accurate You can find the remaining tape time, etc.

Next, a reel calculation formula for determining the remaining tape time, etc. is shown below. The calculation here uses the tape thickness d. Now, let the tape length from the tape start end be LT, the elapsed time be tT, and the area of the tape thickness wound on the take-up side be ST, then ST = π(rT 2 - rh 2 )
LT = π(rT2-rh2)/d
Since tT = LT /v0, tT =
π(rT 2 −rh 2 )/d・v0
…■
Substituting the previous formula ■ into this, the elapsed time tT becomes
π A2 ・v
0 2 tT =────(──────
TT2-rh2)
…■ d・v0 4
It becomes π2. Similarly, if the remaining amount time is tS, then
π A2 ・v0
2 tS =────(────── T
S2-rh2)
…■ d・v0 4π
It becomes 2. By substituting the value obtained above for the hub diameter rh in these formulas ■ and ■, the elapsed time tT and the remaining amount time t
S can be found and displayed.

In the above reel calculation, conventionally a fixed value was substituted for the hub diameter, which resulted in incorrect data being output for tapes with different hub diameters, but this embodiment eliminates this. , can output accurate data. In other words, the elapsed time tT from the beginning of the tape
Information such as the remaining tape time tS and the number of minutes of the tape being used can be displayed on the display 12, and this information can be displayed accurately regardless of the hub diameter of the tape. Become something.

In this embodiment, a fixed value is substituted for the tape thickness d, but the tape thickness d can also be calculated by using the following equation. On the take-up side reel,
Here, since the method of calculating the tape thickness d is not the gist of the present invention, detailed explanation will be omitted.

By substituting these equations into the equations ■ and ■,
The elapsed time tT from the beginning of the tape is 2π2 ・nT
A2 ・v0 2 tT =──
──────────(───────TT 2 -rh
2)…(10) A・v0 2
(TT - TT0) 4π2 Tape remaining time tS is 2π2 ・nS
A2 ・v0 2 tS =─
──────────(───────TS 2 -r
h 2 )…(11) A・v0
2 (TS0-TS) 4π2. In addition, the tape recording (playback) time tTAPE is
tTAPE=tT+tS

...(12) becomes. By substituting the hub diameter rh determined above into these equations, the tape thickness d and the hub diameter rh are both correct values, making it possible to display the remaining amount time, etc. more accurately.

[0015]

As described above, according to the method and apparatus of the present invention, the pulse period obtained by the rotation of the tape reel on the take-up side or the supply side, the rotation speed of the same reel, the tape speed, and the tape thickness are used. The tape reel hub diameter is calculated. The hub diameter determined by this calculation is accurate regardless of the type of tape. In this calculation, in the formula for calculating the radius of the tape wound on the tape reel on the take-up side and the hub at the initial setting, the diameter of the tape at the beginning of the tape is used as the hub diameter, or the radius of the tape wound on the tape reel on the supply side and the hub In the formula for determining the radius of , the end of the tape is taken as the hub diameter. Then, the reel pulse calculation is performed using the hub diameter determined by this calculation, and the remaining time of the tape, etc. can be accurately displayed. In this regard, conventionally,
In order to display the remaining tape time, etc., reel pulse calculations were performed by substituting a fixed value for the hub diameter, so when tapes with different hub diameters were used, the display of the remaining tape time, etc. This was causing an error. In contrast, in the present invention, since the hub diameter determined by the above calculation is accurate, it is possible to accurately display remaining amount time, etc. Therefore, also
In order to protect the tape, running control such as slowing down the tape speed at the end of the tape can be appropriately performed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a tape control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a tape supply side and a take-up side for explaining calculation formulas according to the present invention.

[Explanation of symbols]

1 Microcomputer 3 Supply side tape reel 4 Take-up side tape reel 5,6 Sensor 13 Memory

Claims (6)

[Claims] [Claim 1] The tape reel hub diameter is determined by calculation using the pulse period obtained by the rotation of the tape reel on the take-up side, the number of revolutions of the reel from the initial setting, the tape speed, and the tape thickness. How to detect tape reel hub diameter. [Claim 2] The calculation according to claim 1 is performed by setting the radius of the tape and hub wound on the take-up tape reel at the time of initial setting as rT0, the tape thickness as d, and the pulse period of the take-up tape reel as TT. , when the number of rotations of the take-up tape reel from the initial setting is nT, the tape speed is v0, and the number of poles of the tape reel is A, the formula rT0=(A・v0/2π)TT −d・nT is written. A tape reel hub diameter detection method characterized in that rT0 near the beginning of the tape is used as the hub diameter. [Claim 3] The tape reel hub diameter is determined by calculation using the rotation period of the tape reel on the supply side at the time of initial setting, the number of revolutions of the same reel from the time of initial setting, the tape speed, and the tape thickness. How to detect tape reel hub diameter. 4. In the calculation described in claim 3, the radius of the tape and hub wound on the supply tape reel is rS, the tape thickness is d, and the initial pulse period of the supply tape reel is T.
S0, the number of revolutions of the tape reel on the supply side from the initial setting is nS, the tape speed is v0, the number of poles of the tape reel is A
A tape reel hub diameter detection method characterized in that rS = (A·v0 /2π)TS0−d·nS is used, and rS near the end of the tape is defined as the hub diameter. 5. A tape reel is obtained by performing a predetermined calculation using a rotational speed detection means that generates a pulse proportional to the number of rotations of the tape reel on the take-up side and a predetermined pulse period obtained from the rotational speed detection means. calculation means for calculating the hub diameter, and the calculation means calculates the radius of the tape wound on the take-up tape reel and the hub at the time of initial setting by r.
When T0 is the tape thickness, d is the pulse period of the take-up tape reel, TT is the rotational speed of the take-up tape reel from the initial setting, is the tape speed v0, and is the number of poles of the tape reel as A. A tape reel hub diameter detection device characterized by using the formula rT0=(A·v0/2π)TT−d·nT and setting rT0 near the beginning of the tape as the hub diameter. 6. A tape reel hub by performing a predetermined calculation using a rotation speed detection means that generates a pulse proportional to the rotation speed of the supply side tape reel and a predetermined pulse period obtained from the rotation speed detection means. The calculation means calculates the radius of the tape and hub wound on the supply tape reel as rS, the tape thickness as d, and the initial pulse period of the supply tape reel as TS0.
, the number of rotations of the supply tape reel from the initial setting is nS
, when the tape speed is v0 and the number of poles of the tape reel is A, rS = (A・v0/2π)TS0−d・n
A tape reel hub diameter detection device characterized in that the hub diameter is determined by rS near the end of the tape using the formula S.