JP2000011489A - Method for automatically discriminating kind of analog tape, error by kind correction method and slack correction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve precision in a counter and to reduce an error in a timer setting time. SOLUTION: Tape length and tape thickness of an analog tape 1 of a cassette tape recorder 4 and the time data of a reel pulse inputted from a reel base to a microcomputer 7 detected by a reel pulse detection part 5 are operation processed by the microcomputer 7 as input values, and a tape kind is automatically discriminated. Further, error by tape kind detection operation corrects a moving error in the tape caused by performing mechanical operation by making the kind information of the tape stored in a memory 9 a parameter of operation. Further, related to the slack correction in the tape, count control is performed using a correlation of rotation read in from two reels 2, 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analog cassette tape recorder which performs automatic discrimination of a tape type characteristic for each maker and mechanical operation in order to improve the accuracy of a counter at the time of reproduction, fast-forward and rewind. The present invention relates to a method for correcting a time error accompanying the above-mentioned method and a method for correcting a tape due to slack.

[0002]

2. Description of the Related Art FIG. 6 shows an analog tape stretched on a supply reel and a take-up reel of an analog cassette tape recorder to which the present invention is applied.
(1) shows a state in which the analog tape 1 is wound on the supply side reel 2 and is not wound on the take-up side reel 3, and (2) shows a state in which the analog tape 1 is wound from the supply side reel 2 on the take-up side reel 3. This shows the state of the analog tape after a certain time has passed.

In FIG. 6, assuming that the length L of the tape and the thickness D of the tape are always constant, a combination of the winding width of the reel and the tape is always treated as a circle, and is always 2.
The sum of the areas of two circles is constant. Using this principle,
(Equation 1) to (Equation 6) can be derived as follows.
However, the condition is that the tape length / tape thickness is the same for the same tape with the tape wound tightly.

[0004]

R0 ² + R0 ² = r1 ² + r2 ² r1 ² = r0 ² + R0 ² -r2 ² where r0: reel hub radius R0: tape maximum winding radius r1: supply side tape winding radius r2: take-up side tape winding radius From the above conditions, the area including the reel base and the winding width of the tape is constant.

[0005]

## EQU2 ## r1 ² = K−r2 ² (constant K = constant)

[0006]

## EQU3 ## r1 = √ (K−r2 ² )

[0007]

V = r1 × ω1 = r2 × ω2 where ω1: Reel base rotation speed on the supply side ω2: Reel base rotation speed on the take-up side V: Tape running speed

[0008]

(Equation 5)

[0009]

(Equation 6)

Using the equations (1) to (6), the angular velocity ω is generally derived by detecting rotation from a Hall element mounted on a reel base. By inputting the rotation detection signal to a microcomputer serving as an arithmetic means and performing arithmetic processing, the linear time display of the counter is enabled.

[0011]

However, in the above-described conventional configuration, since the conditions are considered under the condition that the tape length and the tape thickness are the same, actually, if these conditions are different, it takes time. There is a problem that an error occurs.

The thickness of the tape varies depending on the type of the tape.
-60 is the same thickness, C-90 is slightly thinner, C-1
At 20 the thickness is half that of C-60. In addition, although it is unlikely to occur in a normal deck operation, when a slack occurs due to a mechanical operation, the reel is rotated only on the take-up side to cause a time error due to the tightening operation.

The present invention solves the above-mentioned conventional problems, and provides a method for automatically determining the type of tape, a method for detecting an error for each type of tape, and a method for correcting the slack of the tape for deriving the accuracy of the counter as accurately as possible. The purpose is to do.

[0014]

In order to achieve this object, an automatic tape type discriminating method according to the present invention comprises a tape length, a tape thickness, and time data of a reel pulse input from a reel base to a microcomputer. Is input to the microcomputer to perform arithmetic processing.

The method of correcting the type error of an analog tape according to the present invention is characterized in that a tape movement error caused by performing a mechanical operation is corrected using the type information of the tape stored in a memory as a parameter of calculation. I do.

Further, according to the method of correcting slack of an analog tape of the present invention, an error caused by a tightening operation on a single-side reel is reduced.
It is characterized in that count control can always be performed as a state in which the tape is densely wound by utilizing the correlation between rotations read from two reels.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing the configuration of an apparatus for performing an analog tape type automatic discrimination method according to Embodiment 1 of the present invention. In FIG.
4 is a cassette tape recorder in which the analog tape 1 is stretched on the supply side reel 2 and the take-up side reel 3, 5 is a reel pulse detector, 6 is a parameter to the microcomputer 7, 8 is an operation of the microcomputer 7 The result storage RAM 9 is a memory (EEPRO).
M).

Next, the operation of FIG. 1 will be described. For automatic discrimination of the tape type, the cassette tape recorder 4 is set in a reproducing state for a certain period, and pulse signals from both reels 2 and 3 of the cassette tape recorder 4 are supplied to the reels. The pulse detection unit 5 detects with the Hall element and the microcomputer 7
Enter Based on the input reel pulse, it is possible to measure the rotation speed and the angular speed of each reel unit within a certain period (elapsed time) during the certain period. The measured data is referred to as parameter 6. From this information, the microcomputer 7 can detect the hub diameter and the tape thickness of the reels 2 and 3 of the cassette tape recorder 4. This result is stored in the RAM 8 in the microcomputer.
The data in the RAM 8 is backed up in a memory (EEPROM) 9 so that the information is not lost even when the power of the cassette tape recorder 4 is turned off next time.

FIG. 2 shows a backup memory (EEP).
The data stored in the ROM 9 is addressed by manufacturer and tape time, and the hub diameter of the reel and the tape thickness can be detected from the manufacturer and the tape time.

That is, the type of the analog tape can be automatically determined.

(Embodiment 2) FIG. 3 is a flowchart showing an error correction method for each type of analog tape according to Embodiment 2 of the present invention. The second embodiment is based on the first embodiment (FIG. 1), and is a method of correcting using a one-sided time error of the tape type stored in the memory 9. First,
No correction is performed during the tape type determination (S1). Upon completion of the determination, the time error data corresponding to the currently recognized tape type in the memory (EEPROM) 9 is read into the RAM 8 (S2). Then, the microcomputer 7 calculates the ratio of the error data to the tape single-sided time (S
3). As a result, this data is the ratio of the time correction target on one side of the tape. The counter correction accuracy for 1 second is set to 1/100 second (10 ms), and the value calculated in the process of (S3) and the following calculation process of (Expression 7) are performed (S4).

[0023]

[Mathematical formula 7] 10 ms ± (10 ms × (S3) calculation result) The time obtained by the above calculation result is used as a timer interrupt cycle, and the timer is started as counter control (S
5).

As a result, the time count on this tape is calculated based on the corrected time.

(Embodiment 3) FIG. 4 is a diagram showing a method for correcting sag of an analog tape according to Embodiment 3 of the present invention. When the slack 1a of the tape 1 occurs as shown in FIG. 4, the change in the movement is detected based on the correlation between the angular velocities of the two reels 2 and 3, utilizing the fact that the tape is wound on the take-up side reel 3. .

FIG. 5 is a diagram showing the relationship between the rotational speed (angular speed) ω of both reels and the time (t) of the slack absorbing operation.
Here, the portion where only the take-up side reel 3 is rotating from the point where the slack 1a occurs is not the ideal stretched state of the tape indicated by the broken line as shown in FIG. The movement of this angular velocity is always monitored by sampling S during the mechanical operation by software. When a difference of 10% or more with respect to the theoretical value occurs, the operation of the counter is stopped as slack detection, and the counting is restarted when returning to the theoretical value. The sampling for detecting the slack is 10% of 1 second, which is the base time of the counter display, and 1%.
00 ms. By always sampling and monitoring the movement of the angular velocity ω, the slack can be easily detected.

[0027]

As described above, according to the present invention, the automatic discrimination of the analog tape is performed by performing the reproducing operation, so that it is not necessary to change the mechanism for discriminating the tape itself. The recorder does not require an input switch for type determination. In addition, by storing error correction data for each tape in a memory and performing correction with a determined value obtained as a result of arithmetic processing by a microcomputer, accurate time display is possible. In addition, the slack correction always monitors the relationship between the movements of both reels, so that the time corresponding to the slack in the fast-forwarding and rewinding operations is accurately counted, and also occurs due to the movement of the mechanism during the search between songs. If the slack is absorbed, the beginning of the song can be accurately found without breaking the beginning of the song.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an apparatus for performing an analog tape type automatic discrimination method according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a backed-up memory image of FIG. 1;

FIG. 3 is a flowchart illustrating an error correction method for each analog tape type according to the second embodiment of the present invention;

FIG. 4 is a diagram showing a sag correcting method for an analog tape according to a third embodiment of the present invention;

FIG. 5 is a diagram showing the relationship between the rotational speeds of both reels and the time of the slack absorbing operation in FIG. 4;

FIG. 6 is a diagram showing an analog tape stretched on a supply-side reel and a take-up-side reel of an analog cassette tape recorder to which the present invention is applied;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Analog tape 2 Supply side reel 3 Takeup side reel 4 Cassette tape recorder 5 Reel pulse detector 6 Parameter to microcomputer 7 Microcomputer 8 Calculation result storage RAM 9 Memory (EEPROM)

Claims (3)

[Claims] 1. An analog tape is set in a reproducing state for a certain period, pulse signals from both reels on a supply side and a take-up side are input to arithmetic means, and the rotation speed of both reels within a certain period is determined based on the reel pulse signal. And angular velocity,
Using the measured data as parameters, the hub diameter and the tape thickness of both reels are detected, the type of analog tape is automatically determined, and the hub diameter and the tape thickness data are stored in storage means. A method for automatically determining the type of analog tape. 2. After the type of the analog tape is determined, the time error data on one side of the tape corresponding to the type of the analog tape currently recognized is read out from the storage means, and the error data on one side of the tape is calculated by the arithmetic means. A timer setting time is calculated from the obtained error by a calculating means, and a timer is started, whereby an error correction method for each type of analog tape is provided. 3. When a slack occurs in an analog tape, the change in movement is determined based on the correlation between the angular velocities of both the supply side and take-up side reels by utilizing the fact that the tape is wound on the take-up side reel. A method for correcting slack in an analog tape, comprising detecting and correcting an error due to slack of the tape based on a rotational movement distance of both reels.