KR100195614B1 - Method for detecting hub size in cassette tape player - Google Patents

Abstract

The present invention relates to a method for determining the hub size of a cassette. When a video tape is inserted, an error in the detection process at the beginning and the end is prevented due to the thickness difference between the magnetization area and the lead area of the video tape, and the magnetization of the video tape is performed. In order to prevent the head from being damaged by the contact between the area and the lead area contacting the head, and to prevent the misjudgment on the boundary point between the large hub and the small hub, and to determine the size of the hub more precisely and accurately, A method for determining the hub size of a cassette, comprising: a first step of driving a video tape in a forward direction for a first predetermined time by controlling a servo system when a cassette is inserted into a deck; A second step of checking a rotation change amount of the supply reel and the winding reel from the video tape driven by the first step; A third process of causing the video tape to travel for a second predetermined time in a direction in which the video tape is less wound, according to the rotational change amounts of the supply reel and the winding reel checked through the second process; A fourth step of calculating a neural function by calculating feed reel and reel side areas for video tapes having different running times, and inputting and calculating the calculated area data into a neural network algorithm; And calculating a feed reel and winding reel side area of the video tape to be determined, and substituting the calculated area data into the neural function to determine a hub size.

Description

How to determine the hub size of a cassette

The present invention relates to a method for determining the hub size of a cassette, and more particularly, in a plurality of cassettes having different hub sizes, a hub mounted on each video tape while securing a running margin when the cassette is initially inserted. The present invention relates to a method for determining the hub size of a cassette to determine the size of a circuit using a neural network algorithm.

In general, a video tape recorder (VTR) is provided with sensing means for detecting the beginning and the end of a video tape. This is due to the inertia force of the video tape to be conveyed because when the user selects the function to transfer the video tape at high speed, the high speed transfer function is not stopped even though the video tape that has been transported at the high speed has reached the beginning or the end. This is to prevent a problem that may damage the video tape, such as the tape is broken or stretched.

As shown in FIG. 1, the sensing means includes a light emitting element 2 protrudingly mounted at a predetermined position of the deck 1 and a light signal (light) emitted from the light emitting element 2. It consists of a pair of light receiving element 3 on the left and right sides of (1).

In addition, as shown in FIG. 2, a typical home video system (VHS) standard video tape includes an opaque magnetization area coated with a magnetization material to record various types of information, and a start of the video tape. It is divided into a transparent lead area having a predetermined length (about 2 meters) at the end.

In a typical video tape recorder having such a configuration, the process of detecting the beginning and the end of the tape is as follows.

When the video tape travels, the pair of light receiving elements 3 detect different signals depending on the magnetization region and lead region of the video tape. That is, when the video tape is located in the magnetization region, the optical signal output from the light emitting element 2 is blocked by the magnetization region of the video tape and cannot be transmitted to the light receiving element 3. For this reason, the light receiving element 3 is turned off and outputs the travel control signal of the video tape to the control means for controlling the travel state of the video tape. Thus, the video tape runs normally.

On the other hand, when the video tape is located in the lead region, the optical signal output from the light emitting element 2 passes through the transparent lead region of the video tape and is transmitted to the light receiving element 3. As a result, the light receiving element 3 is turned on to output the stop control signal of the video tape to the control means. Thus, the video tape is stopped.

However, the conventional video tape start and end position sensing methods as described above have to have one light emitting device and at least two light receiving devices, and thus there is a problem that the production cost of the product increases.

In addition, the above-described light emitting device is mounted to the center of the deck protruding, and the light receiving device is mounted on the side of the deck using a separate printed circuit board, so the mounting process of the deck by the mounting position of the light emitting device and the light receiving device This complexity is difficult, there is a problem that the work efficiency is lowered.

In addition, in order to prevent the light receiving element from malfunctioning due to external light, it must be housed in a separate case, and thus a separate free space is required to mount such a separate case in the deck, thereby realizing miniaturization of a video tape recorder. There was a problem that it is difficult.

As a result, in order to solve the above problems, it is effective to remove the light emitting device and the light receiving device, and to determine the size of the hub to accurately detect the beginning and the end of the tape in the state where the light emitting device and the light receiving device are removed. very important.

Conventional video tapes are classified into various types corresponding to the total running time in the normal mode. That is, the total running time of video tape is largely for 20 minutes (T-20), 60 minutes (T-60), 80 minutes (T-80), 100 minutes (T-100), 120 minutes (T-120), And for 160 minutes (T-160), and for each video tape having such a total driving time, the size of the hub for winding the video tape is about 20 minutes and 60 minutes for the large hub (diameter 31.02 mm). Video tapes with a total running time of 80 minutes or more use a small hub (13.06 mm in diameter). The size of the hub is an important factor in the reel motor control process for moving the tape at a constant linear velocity in the video tape recorder, and also calculates the start and end of the video tape in the video tape recorder without the light emitting and receiving elements. It is a very important factor.

3 is a schematic block diagram for determining the hub size in a conventional video tape recorder. In FIG. 3, since the same reference numerals as used in FIGS. 1 to 2 denote the same components, redundant descriptions thereof will be omitted.

Referring to FIG. 3, a frequency generator 4 is a capstan motor that is detected during one revolution of each reel from the supply reel and take-up reel mounted on the deck 1. Converts the number of revolutions into a frequency and outputs it. That is, the capstan frequency per rotation of the supply reel (hereinafter abbreviated as 'PS') and the capstan frequency per rotation of the winding reel (hereinafter abbreviated as 'PT') are respectively generated to generate the frequency of the fish pulse type. Output to the microcomputer 5.

In the PS and PT generated from the frequency generator 4, when one video tape is traveled and detected, the combined value of PS2 and PT2 is always constant regardless of the running state of the video tape (PS2 + PT2 = PC2). Thus, when the video tape runs, the microcomputer 5 calculates PC2 using the PS and PT generated from the frequency generator 4.

On the other hand, the memory 6 stores PC2 values corresponding to each type of video tape, and the microcomputer 5 compares the PC2 value of the video tape currently being driven with the value of PC2 stored in the memory 6. The large or small hubs were determined linearly according to the comparison results.

However, as described above, since a large hub and a small hub are linearly divided, a hub determination error occurs at a boundary point between a large hub and a small hub as shown in FIG. 4 due to video tape tolerances. There was this.

In addition, when the video tape is a non-standard product, since the PC2 value of the total running time of the video tape has a large error, there is a problem that the error of hub determination occurs more frequently at the boundary point between the large hub and the small hub as described above. .

Also, in the video tape recorder with the start and end sensors removed, when the video tape is driven at the beginning and the end, the video tape starts and ends due to the difference in thickness between the lead area and the magnetization area of the video tape. An error occurs in the process of detecting.

In addition, when the video tape is positioned at the beginning or the end, when the user inserts and plays the video tape in the video tape recorder, the joint portion of the magnetized area and the lead area of the video tape comes into contact with the head, thereby damaging the head. To reduce the life of the head.

Accordingly, an object of the present invention is to solve the above-described problem, and an object of the present invention is to prevent an error in starting and ending detection process due to a thickness difference between a magnetized region and a lead region of a video tape when a video tape is inserted. The present invention provides a method for determining the hub size of a cassette.

Further, another object of the present invention is to provide a method for determining the hub size of a cassette, which prevents the head from being damaged by the contact between the magnetized region and the lead region of the video tape contacting the head.

In addition, by learning the PS2 and PT2 data in a neural network algorithm, it is possible to easily determine the hub size of a video tape that can be easily responded to when determining the size of a hub mounted on various types of video tapes having different PS2 and PT2. Is in.

1 is a schematic structural diagram of a conventional video tape recorder;

2 is a schematic structural diagram of a conventional VHS standard cassette;

3 is a schematic block diagram for determining a hub size in a conventional video tape recorder.

4 is a state diagram of discrimination between a large hub and a small hub according to a conventional hub size determination method;

5 is a schematic block diagram of a video tape recorder for performing a method for determining a hub size of a cassette according to the present invention;

6 is an operation flowchart of the microcomputer shown in FIG. 5;

7 is a state diagram of discrimination between a large hub and a small hub according to the hub size determination method according to the present invention.

* Explanation of symbols used in the main part of the drawing

4: frequency generator

5: microcomputer

6: memory

7: Supply reel detector

8: winding reel detection unit

9: servo system

A feature of the present invention for achieving the above object is a method of determining the hub size of a cassette: when the cassette is inserted into the deck, the servo system is controlled to drive the video tape in the forward direction for a first predetermined time. First process; A second step of checking a rotation change amount of the supply reel and the winding reel from the video tape driven by the first step; A third process of causing the video tape to travel for a second predetermined time in a direction in which the video tape is less wound, according to the rotational change amounts of the supply reel and the winding reel checked through the second process; A fourth step of calculating a neural function by calculating feed reel and reel side areas for video tapes having different running times, and inputting and calculating the calculated area data into a neural network algorithm; And calculating a hub size of the cassette for the video tape to be determined, and performing a fifth process of determining the hub size by substituting the calculated area data into the neural function. .

In the above-described feature of the present invention, the above-described feed reel and winding reel-side area is calculated from the values PS2 and PT2 obtained by multiplying the rotation speeds PS and PT of the capstan motor during one rotation of the supply reel and winding reel. It is desirable to.

Hereinafter, a preferred embodiment of a method for determining the hub size of a cassette according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 5 is a schematic block diagram for performing a hub size determination method of a videotape according to the present invention, and FIG. 6 is a flowchart illustrating the operation of the microcomputer shown in FIG. As shown in FIG. 5, since the configuration block of the present invention is similar to the conventional configuration block shown in FIG. 3, redundant description thereof will be omitted, and only the essential elements of the present invention will be described.

Referring to FIG. 5, in addition to the components of FIG. 3, a supply reel detecting unit 7 for detecting an amount of rotation of a supply reel and a winding reel detection for detecting an amount of rotation of a take-up reel may be used. The unit 8, the servo system 9 for controlling the drive state of the deck, and the microcomputer 5 for controlling the above-described components are comprised.

The operation of the present invention having the configuration as described above will be described with reference to FIG.

The neural network applied to the present invention refers to an information processing apparatus assembled by modeling the human brain, and has a structure in which a simple computing element called a unit is connected in a network shape. The information is processed in parallel, has a learning function, fuzzy control, and the like, and is being studied as bringing a computer closer to a human being.

The neural network theory first inputs the learning data into the neural network, calculates a neural function based on the inputted learning data, and codes the calculated neural function into the processor, thereby generating new neural data. A stable judgment effect can be obtained.

Accordingly, the microcomputer 5 detects the area of the hubs and the video tapes wound on the hubs for various types of video tapes, inputs the detected area values as learning data, and inputs them into the neural network algorithm for learning. Accordingly, the most ideal hub discrimination function (neural function) for each area value is estimated.

Here, the above-described area value may be detected using PS2 and PT2. That is, since each area value of a normal video tape is represented by a value proportional to PS2 and PT2, the area value may be replaced with PS2 and PT2. Therefore, the hub size determination process to be described later is limited to the method using both PS2 and PT2.

The microcomputer 5 then checks whether a cassette (not shown) has been inserted into the deck (not shown) (S1). If it is determined in this step S1 that the cassette has not been inserted into the deck, the microcomputer 5 returns to the above-described step S1 to continue checking whether the cassette has been inserted into the deck.

If it is determined in step S1 that the cassette is inserted into the deck, the microcomputer 5 controls the servo system 9 to drive the video tape in the forward direction (S2), and then the supply reel detecting unit 7 ) And the reel rotation amount data from the winding reel detection unit 8 (S3).

Thereafter, the microcomputer 5 checks whether the rotation amount of the supply reel is greater than the rotation amount of the winding reel (S4), and if it is determined that the rotation amount of the supply reel is greater than the rotation amount of the winding reel, the servo system 9 The control is performed to drive the video tape in the forward direction for a predetermined time to secure a margin of the video tape (S5).

If it is determined in the above-described step S4 that the rotation amount of the supply reel is not greater than the rotation amount of the winding reel, the microcomputer 5 controls the servo system 9 to drive the video tape in the reverse direction for a predetermined time. To secure the margin of the video tape (S6).

After performing the above-described steps S5 and S6, the microcomputer 5 stops the running state of the video tape (S7), and then uses the PS and PT values generated from the frequency generator 4 to determine the PS2 and the PS2. PT2 is calculated, respectively (S8). Thereafter, the microcomputer 5 inputs the PS2 and PT2 values detected in the above-described step S8 into the above-described neural function, and calculates the result (hub size determination result) accordingly (S9).

Through the above-described process, the large hub and the small hub are non-linearly divided as shown in FIG. 7, and even in the case of the video tape located at the boundary point between the large hub and the small hub, the hub size is accurately and precisely Is determined.

In conclusion, according to the method for determining the hub size of the cassette according to the present invention as described above, after the video tape is driven when the cassette is inserted into the deck, the winding degree of the supply reel and the winding reel is analyzed, and the video is analyzed according to the analyzed result. By running the video tape in the reel direction where the tape is less wound for a predetermined time, there is an advantage that the margin of the video tape can be secured, and an error in detecting the beginning and the end of the video tape can be prevented.

In addition, as described above, securing the margin of the video tape prevents the junction portion of the magnetized region and the lead region of the video tape from contacting the head, thereby preventing damage to the head, thereby extending the life of the video tape recorder. There is an advantage to this.

In addition, by using the PS2 and PT2 values as learning data, the neural network algorithm is trained to determine the size of the hub, thereby preventing the misjudgment on the boundary point between the large hub and the small hub, and more precisely and accurately determining the hub size. There is an advantage to this.

Claims (2)

In the method for determining the hub size of a cassette: A first step of controlling the servo system when the cassette is inserted into the deck to drive the video tape in the forward direction for a first predetermined time; A second step of checking a rotation change amount of the supply reel and the winding reel from the video tape driven by the first step; A third process of causing the video tape to travel for a second predetermined time in a direction in which the video tape is less wound, according to the rotational change amounts of the supply reel and the winding reel checked through the second process; A fourth step of calculating a neural function by calculating feed reel and reel side areas for video tapes having different running times, and inputting and calculating the calculated area data into a neural network algorithm; And And a fifth step of calculating a feed reel and winding reel side area for the video tape to be determined and substituting the calculated area data into the neural function to determine a hub size. The method of claim 1, wherein the supply reel and the winding reel side area, A method for determining the hub size of a cassette, characterized in that it is calculated from a square value (PS2 and PT2) of the rotational speed (PS and PT) of the capstan motor during one rotation of the supply reel and the winding reel.