JPH0378701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a tape recorder that is equipped with a cassette tape and records and reproduces information.

(Prior art and problems to be solved by the invention) Conventional video tape recorders have a timer recording mode in which a timer automatically records from a recording start time set by manual input until a recording end time a certain period of time later. It is known that it has When using this type of video tape recorder in timer recording mode, if the remaining tape capacity of the loaded cassette tape is less than the recording time from the recording start time to the recording end time set in timer recording mode. Although recording automatically starts from the recording start time, the cassette tape sometimes reaches the end of the tape before the set recording end time, resulting in end-of-record recording. Conventionally, it is not possible to predict whether this end-of-record recording will occur when a cassette tape is loaded, so it is necessary to use a cassette tape that has a remaining tape time that significantly exceeds the recording time. Since the selection process requires a lot of effort, in many cases there has been a tendency to install a new cassette tape. For this reason, a cassette tape that has been partially recorded but still has a recordable portion cannot be used and is wasted.

In addition, since a cassette tape is used that has a remaining tape time that greatly exceeds the recording time, an unrecorded portion remains at the end of the cassette tape, making it impossible to use the tape effectively until the end. .

Therefore, in the present invention, if the remaining tape time of the loaded cassette tape is shorter than the recording time set when setting the timer recording mode, the recording time set when setting the timer recording mode is Recording is performed from the recording start time in the tape running mode, and then the tape running mode is automatically switched to a lower speed tape running mode than the set tape running mode, and recording is performed so that the recording end time and tape end coincide. It is an object of the present invention to provide a tape recorder that can perform complete recording without significantly reducing recording quality.

(Embodiment) An embodiment of the tape recorder of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the main parts of a video tape recorder that is an embodiment of the present invention, and FIG. 2 is a flowchart showing the required operations of a microcomputer used in the video tape recorder. .

In FIG. 1, reference numeral 1 denotes a tape remaining amount time detector which detects the remaining tape amount time of a cassette tape 3 mounted in a cassette housing 2 of a video tape recorder and outputs a tape remaining amount signal. Various types of tape remaining time detectors have been proposed in the past, but in this embodiment, the tape remaining amount time detection method disclosed in Japanese Patent Application No. 172246/1983 filed earlier by the present applicant was used. The device was applied.

This tape remaining amount time detector 1 runs the tape 3a of the loaded cassette tape 3 for a trial run, and detects the supply side tape reel 3b which is rotating while the tape is running.
The period or number of rotations of the reel disk of the tape reel 3c on the take-up side is detected, and the period or number of rotations of the reel disk of the tape reel 3b on the supply side and the tape reel 3c on the take-up side are added, and the added value is calculated. is larger or smaller than a threshold value that is preset (manually input by the operator using a changeover switch or the like provided in a predetermined operating section of the housing 4) based on the type of tape reel with a different hub diameter. The hub diameter of the tape reel in use is determined, and the amount of tape wound on the supply tape reel 3b is determined based on the cycle or rotational speed of the reel disk of the supply tape reel 3b and the determined hub diameter. It is configured to detect the remaining tape time.

In this embodiment, the trial running speed of the tape 3a is made to match the speed in the standard running mode, and the tape remaining amount signal is a signal corresponding to the tape remaining amount time t in this standard running mode. Note that the tape 3a of the loaded cassette tape 3 is once run for a test run, so the test run is slightly wasted, but after the remaining tape time is detected, it is returned to its original position using the automatic marker method. tape 3
By rewinding a, it is possible to avoid wasting the test run.

4a, 4b, 4c, and 4d are pushbuttons provided on the housing 4 for setting the recording mode (tape running mode), and the pushbutton 4a is for the standard running mode, the pushbutton 4b is for the 1/2 speed mode, and the pushbutton 4b is for the 1/2 speed mode. The push button 4c is for the 1/4 speed mode, and the push button 4d is for the 1/6 speed mode. And this push button 4
When any one of a to 4d is pressed, an on signal is output to the microcomputer 5, and an LED (not shown) placed inside the pressed push button lights up, causing the tape indicated by that push button to light up. Notify the operator that the vehicle has been set to driving mode.

Reference numeral 6 denotes a timer set operating section provided in the housing 4, and by manually inputting the recording start time and recording end time of timer recording, the timer set operating section 6 sends a recording start time signal and a recording end time signal to the microcomputer 5. is supplied.

The microcomputer 5 consists of a comparator, a discriminator, and a calculator. To explain with reference to the flowchart in FIG. 2, first, in this comparator,
Based on the recording start time signal and the recording end time signal supplied from the timer set operation section 6, the recording time T is calculated by subtracting the recording start time t _i from the recording end time t _f (t _f −t _i =T ).

Next, the tape remaining amount time t in the standard running mode is calculated from the tape remaining amount signal supplied from the tape remaining amount time detector 1, and the push buttons 4a to 4a for setting the tape running mode provided on the housing 4 are calculated.
4d, the desired tape running mode set when setting the timer recording mode, 1/
m in the m-times speed mode (m=1, 2, 4, 6) is set to the variable x.

Then, in the variable x for which m is set, 1/
The recording time T is subtracted from the tape remaining time xt in the x-time speed mode (t is the tape remaining time in the standard running mode), and it is determined whether this difference is positive or negative (xt-T>0?). If this difference is positive,
This shows that the remaining tape time mt in 1/m double speed mode is greater than the recording time T.
In this set desired tape running mode, 1/m double speed mode, complete recording is possible. On the other hand, if the difference is negative, it means that the recording time T is larger than the remaining tape time mt in 1/m double speed mode, which means that complete recording is not possible in this 1/m double speed mode. Become. Therefore, if the difference is negative, the variable x is reset to a value indicating m of the slowest tape running mode, which is the highest speed among the tape running modes slower than this 1/m double speed mode. , for the variable x in which the value of m indicating the low-speed tape running mode is set, the recording time T is again subtracted from the tape remaining time xt, and it is determined whether this difference is positive or negative. This judgment operation is repeated (discriminator) until there is a low-speed tape running mode that allows complete recording (until the difference obtained by subtracting the recording time T from the remaining tape time xt becomes positive). That is, in this embodiment, the desired tape running mode set is the standard running mode (m=1).
If complete recording is not possible in this standard running mode, the cases of m = 2, 4, and 6 are sequentially determined, and the lower speed tape running mode that allows complete recording is determined. If the tape running mode is 1/2 speed mode (m=2) and complete recording is not possible, the cases of m=4 and 6 are sequentially judged to determine the tape running mode in which complete recording is possible.

Next, if the above comparator and discriminator determine that there is a tape running mode that allows complete recording (xt-T>0), that tape running mode that allows complete recording is changed to timer recording mode. It is determined whether or not it matches the desired tape running mode set at the time of setting the 1/m double speed mode (x=m?), and if they match, the desired tape running mode set. Since complete recording is possible in the 1/m double speed mode, the tape drive mechanism 7 is controlled to perform automatic recording from the recording start time t _i in this 1/m double speed mode, and the recording end time is
Record in 1/m double speed mode up to t _f .

And a tape running mode that allows complete recording,
1/m which is the desired tape running mode set.
If it does not match the double speed mode, this 1/
This means that complete recording is possible in a tape running mode that is slower than the m-times speed mode.
Therefore, we changed the tape running mode on the lower speed side, which allows complete recording, to 1/x double speed mode.
Recording time in 1/m double speed mode is t _n ′1/x
If the recording time in the double speed mode is _tx , the following relational expression holds true.

t _n + t _x = T ... t _{n / m} + t x / /x When recording for time t _x until recording end time t _f in double speed tape running mode, if recording end time t _f and tape end match, 1/m
It is shown that the recording time T is the sum of the recording time t _n in the double speed mode and the recording time t _x in the 1/x double speed mode.

In addition, t _n /m in the above formula is the amount of tape used when recording for a time t _n in the 1/m double speed tape running mode, converted into the time when recording in the standard tape running mode, and t _x /x is the amount of tape used when recording for a time tx in the 1/ _x double speed tape running mode, converted into the time required for recording in the standard tape running mode. Then, when the recording end time t _f and the tape end match, the amount of tape used (in terms of time) when recording for a time t _n in the 1/m double speed tape running mode and the 1/x double speed tape The sum of the tape usage (in terms of time) when recording for time t _x in travel mode is
This indicates that the remaining tape amount time t (which is the amount of tape used when recording in the standard tape running mode) is reached.

Then, by eliminating t _x from this formula, t _n =
If it is in the form, t _n =m(xt-T)/(x-m)...

In this equation, since the values of m, x, t, and T are known, the recording time t _n in the 1/m speed mode can be found by calculating the equation.

Then, based on the recording time t _n and the recording start time t _i in the 1/m double speed mode, the tape running mode switching time t' at which the mode is switched from the 1/m double speed mode to the 1/x double speed mode is calculated. (calculator). As a result, when the recording start time t _i is reached, the microcomputer 5 starts recording in the 1/m double speed mode, which is the desired tape running mode set when the timer recording mode was set by the operator. Recording is started, and when the tape running mode switching time t' is reached, the tape running mode is switched to the lower speed 1/x speed mode by the tape running drive mechanism (switcher) 7, and then recording is started. Recording is performed in this 1/x speed mode until the end time t _f . At this time, the cassette tape 3 is almost at its tape end at the recording end time _tf , and the tape 3a can be used effectively. Furthermore, when playing back the tape cassette 3 recorded in this way, since the video tape recorder is equipped with a function to automatically detect and switch the running mode, there will be no problem even if the tape cassette 3 is switched to a different running mode midway through. can be played without.

In the embodiment shown in FIG. 1, the video tape recorder has a standard running mode, a 1/2x running mode, a 1/4x running mode, and a 1/6x running mode. , it is sufficient to have a standard running mode and a low-speed tape running mode in which the tape runs at a slower speed than the standard running mode, and the running speed of the lower-speed tape running mode is also 1/3.
You are completely free to play at double speed, 1/5x speed, etc.

In a video tape recorder that has only two types of tape running modes: a standard running mode and a tape running mode on the lower speed side that records at a slower speed than the standard running mode, the timer recording mode is set to record in the standard running mode. When the comparator determines that complete recording is not possible in the standard running mode, the judge specifies a lower speed tape running mode, and again determines whether complete recording is possible in this lower speed tape running mode ( Comparator), when it is determined that complete recording is possible in the lower speed tape running mode, it calculates the switching time to switch from the standard running mode to the lower speed tape running mode and performs timer recording, as in the previous embodiment. .

As explained above, if recording is not possible in the desired tape running mode set when setting the timer recording mode, recording is performed as much as possible in the high quality desired tape running mode set. After that, recording is performed in a tape running mode that is slower than that tape running mode until the recording end time, which prevents end-of-record recording and minimizes deterioration in recording quality, making it easier for the operator to It is possible to maintain recording quality to a level that does not cause dissatisfaction, and since it takes less time to select the cassette tape to be used than in the past, it has the advantage of improved usability.

In addition, complete recording can be performed even when using a cassette tape that is partially recorded, so you can use a cassette tape that has an incomplete amount of remaining tape without wasting it. It has the characteristic that it can be used effectively up to the last part.

(Effects of the Invention) As described above, the tape recorder of the present invention has at least a standard tape running mode, a lower speed tape running mode in which the tape is run at a slower speed than the standard tape running mode, and a recording start time and a recording end time. In a tape recorder having a timer recording mode in which timer recording is performed by setting the time and a desired tape running mode, a tape for detecting the tape remaining time in the standard tape running mode of a cassette tape loaded in the tape recorder. The remaining tape amount time in each of the lower speed tape running modes is calculated from the remaining tape amount time detected by the remaining tape amount time detector and the tape remaining amount time in the standard tape running mode detected by this tape remaining amount time detector, and the timer recording is performed. a comparator that compares the recording time obtained from the difference between the recording end time and the recording start time set in the mode with each of the remaining tape lengths; When the tape remaining time in the mode is smaller than the recording time, the tape running mode is in a faster tape running mode among the tape remaining time in each of the lower speed tape running modes that is slower than the desired tape running mode. a discriminator for determining the low-speed tape running mode in which the tape remaining time is greater than the recording time; a recording time for recording halfway in the desired tape running mode; The total recording time recorded in the low-speed tape running mode is the recording time, and the tape usage amount when recording halfway in the desired tape running mode and the subsequent tape running in the low-speed side obtained by the discriminator Since the total amount of tape used when recording in this mode is the tape usage amount obtained from the remaining tape time in the standard tape running mode, calculate the recording time to record halfway in the desired tape running mode. , a calculator for calculating a tape running mode switching time after a recording time for halfway recording in the desired tape running mode from the recording start time set in the timer recording mode; and a switch for switching from the desired tape running mode to the lower speed tape running mode obtained by the discriminator when the switching time arrives, and the desired tape running mode is set to the timer recording mode. When the recording time is longer than the remaining tape time in the desired tape running mode, the low speed obtained by the discriminator from the desired tape running mode at the switching time during recording. Since the recording time was changed to the side tape running mode to match the recordable time on the cassette tape, recording was not possible in the desired tape running mode set when setting the timer recording mode. Even in the case of recording, it is possible to prevent incomplete recording and record complete recording.

As a result, even if you use a cassette tape that has been partially recorded, it is possible to record completely, and a cassette tape with half-finished tape remaining time can be used without wasting it. , even the last part of the tape can be used effectively.

Also, respecting the desired tape running mode set by the operator when setting the timer recording mode, after recording in that desired tape running mode for as long as possible, Since the remaining time is recorded by switching to , it is possible to minimize the deterioration in recording quality and maintain the recording quality to a level that does not cause the operator to feel dissatisfied.

Moreover, since it does not take time to select the cassette tape to be used as in the past, it has extremely excellent effects such as improved usability.

[Brief explanation of drawings]

FIG. 1 is a block system diagram showing the main parts of a video tape recorder which is an embodiment of the tape recorder of the present invention, and FIG. 2 is a flowchart showing the required operations of a microcomputer used in the video tape recorder. be. DESCRIPTION OF SYMBOLS 1... Tape remaining amount time detector, 2... Cassette housing, 3... Cassette tape, 3a... Tape, 3b... Supply side tape reel, 3c... Winding side tape reel, 4... Housing, 5 ...Microcomputer (comparator, judger, calculator),
6...Timer set operation unit, 7...Tape travel drive mechanism (switcher).

Claims (1)

[Claims] 1. At least a standard tape running mode, a lower speed tape running mode in which the tape runs at a slower speed than the standard tape running mode, a recording start time, a recording end time, and a desired tape running mode are set. A tape recorder having a timer recording mode for performing timer recording according to the present invention includes: a tape remaining amount time detector for detecting the remaining tape amount time in the standard tape running mode of the cassette tape loaded in the tape recorder; The tape remaining time in each of the lower speed tape running modes is calculated from the tape remaining time in the standard tape running mode detected by the time detector, and the recording end time set in the timer recording mode is calculated. a comparator that compares the recording time obtained from the difference from the recording start time with each of the remaining tape times; and from the output of this comparator, the remaining tape time in the desired tape running mode is determined as the recording time. If the remaining tape time is greater than the recording time in a higher speed tape running mode among the tape remaining time in each of the lower speed tape running modes that are slower than the desired tape running mode. a discriminator that determines the tape running mode on the lower speed side, a recording time to be recorded halfway in the desired tape running mode, and a recording time to be recorded in the lower speed tape running mode obtained by the discriminator thereafter; The total time becomes the recording time, and the amount of tape used when recording halfway in the desired tape running mode and the amount of tape used when recording in the lower speed tape running mode obtained by the discriminator after that. Since the sum of the above is the tape usage amount obtained from the remaining tape time in the standard tape running mode, the recording time to be recorded halfway in the desired tape running mode is calculated, and the recording time set in the timer recording mode is calculated. a calculator for calculating a tape running mode switching time after a recording time of recording halfway in the desired tape running mode from the recording start time; and a switch for switching from the tape running mode to the lower speed tape running mode obtained by the discriminator, and when the timer recording mode is set in the desired tape running mode, the recording time is set to the desired tape running mode. If the tape remaining time is longer than the tape remaining time in the tape running mode, the recording is performed by switching from the desired tape running mode to the lower speed tape running mode obtained by the discriminator at the switching time during recording. A tape recorder characterized in that the time and the recordable time on the cassette tape match.