JPS5858746B2 - Cassette tape remaining time display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for digitally displaying the remaining amount of time on a cassette tape used in a magnetic recording and reproducing device for a cassette tape.

Conventionally, magnetic recording devices for cassette tapes have been equipped with mechanical or electronic counters that count the distance traveled by the magnetic tape and use this travel count value as a guide to calculate the remaining amount of magnetic tape. It is being

A mechanical counter consists of a character wheel and a counter pulley that moves the character wheel.The counter pulley is connected to a take-up reel stand or a supply reel stand with a rubber belt, and a number proportional to the number of rotations of the reel stand is displayed on the counter. is now displayed.

The electronic counter is configured to electronically count pulses corresponding to the rotation of the reel stand and display this count value numerically. The tape position during recording and playback is indicated by the number of rotations of the reel stand, and the number displayed on the counter does not directly represent the length of the magnetic tape.

Therefore, in order to know the remaining time of a magnetic tape, first measure the total running time and total running count value of the magnetic tape, and then calculate the remaining time of the magnetic tape without performing complicated calculations of the total running time. I couldn't know.

Recently, a pulse signal proportional to the rotation speed of the tape supply reel or take-up reel is extracted from a reel rotation period detector, and a DC converter converts it into a DC signal corresponding to the pulse signal period. It has been proposed that the output drives an indicator to display the remaining time of the tape.

However, devices using such an indicator display the remaining tape time on an analog scale indicated by the pointer, and therefore have the disadvantage that it is not possible to accurately determine the remaining tape time.

In particular, when the remaining tape capacity is running low, it is impossible to know whether the last song can be completely recorded.

Furthermore, it is impossible to accurately locate the beginning of the tape.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cassette tape remaining time display device that can accurately and automatically digitally display the remaining amount of time on a cassette tape.

In order to achieve this purpose, the cassette tape remaining time display device according to the present invention reads the recording time mark written in advance on the surface of the cassette by the tape time setting section, and displays the time specified by this mark. A preset signal is sent, and the tape time counter presets the tape time specified by the time preset signal, and the tape time is subtracted by the presence of a tape running signal indicating that the tape is running, and the contents of the tape time counter are sent to a decoder. / A digital display is made on the display using a driver circuit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the cassette tape remaining amount time display device according to the present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 is a block diagram showing an embodiment of a cassette tape remaining amount time display device according to the present invention, in which 1 is a clock counter that measures time in response to a clock pulse, and 2 is an output of this clock counter. 4 is a display device driven by the decoder/driver circuit 3.

5 is a timer counter that counts high-speed pulses during input of the timer set signal and sets a desired timer time; 6 compares the contents of this timer counter 5 with the contents of the clock counter 1, and compares the contents of both. A comparison circuit outputs a match signal when a match occurs, and 7 is a timer output circuit that receives the match signal from the comparison circuit and sends out a timer output.

Reference numeral 8 indicates a tape time setting section which reads geeks on a mark tape pasted on the side surface of the cassette, which will be described later, using, for example, a photoelectric conversion element, and outputs a time preset signal specified by this mark, and 9 indicates from this tape time setting section. The tape time counter is preset with a tape time specified by a time preset signal, and subtracts the preset tape time using a width time pulse of a tape running signal that is input only while the tape is running.

The tape running signal can be supplied, for example, by extracting a pulse signal from a reel drive system of a magnetic recording/reproducing device in accordance with the rotational speed and converting it into direct current.

Reference numeral 10 denotes a tape end notice display unit which is activated by a tape end notice signal sent out when the tape time counter 9 counts, for example, 5 minutes of remaining tape time; 11 a manually operated timer time display switch (not shown); ) and a tape remaining time display switch (not shown), and when these switches are operated, a switching signal is sent to the display switching circuit 2, and a mark reading signal, which will be described later, is sent to the tape time setting section 8. This is a display control unit that

FIG. 2a is a perspective view showing an example of a mark tape attached to the side of a cassette, and one side of the mark tape displays C30, C45, and C45 tape times for recording and playback of the cassette tape.
Symbols 13 for C60, C90, and Cl2O and mark locations 14 corresponding to these symbols are printed. For example, as shown in the same figure, by filling in black the mark location corresponding to the C60 symbol, the cassette to be pasted is printed. This indicates that the total recording time of the tape is 60 minutes.

The cassette tape 15 shown in FIG. 3 has such a mark tape 12 attached thereto, and when the cassette tape 15 is inserted into a magnetic recording/playback device, the remaining tape time display switch (not shown) of the display control section 11 is pressed. ), the light source turns on for a certain period of time, and the tape time setting section receives a reading signal and reads the mark on the mark tape 12 through the lens 18 with the photoelectric conversion element 17, and outputs a time preset signal corresponding to the mark. Send out.

In the tape time counter 9, if the time preset signal corresponds to the C60 mark, for example, a one-sided recording time of 30 minutes, which is 1/2 of the total recording time of the cassette tape, is preset, and this time is set by the display switching circuit 2, decoder/driver. The time is digitally displayed via the circuit 3 on the display 4 which was displaying the time before the tape remaining time display switch was operated.

After that, when the tape starts recording or playing,
The above-mentioned tape running signal is generated, and while this signal is being supplied, the tape time counter 9 is decremented by one second by the time pulse, and the display 4 also displays a decrement in seconds each time.

Then, when the content of the tape time counter 9, that is, the remaining tape time reaches 5 minutes, the tape end notice display section 10 is driven by the tape end notice signal from the tape time counter 9 to notify that the end of the tape is near.

Furthermore, when it is desired to perform recording or playback on the other side of the cassette tape, the mark tape 12 is attached to a predetermined position on the other side of the tape cassette 16 to mark the remaining amount of the cassette tape in exactly the same way as in the above case. The time can be displayed digitally.

In this embodiment, in addition to displaying the time and remaining tape time, the display switching circuit 2 is switched by operating a timer time display switch (not shown) of the display control section 11, and the timer/counter 5 is displayed in advance. The set timer time can be digitally displayed on the display 4.

Further, when the contents of the timer counter 5 and the clock counter 1 match, the comparator circuit 6 detects this and drives the timer output circuit 7 to send out a timer output.

In the above embodiment, the photoelectric transducer 17 was used to read the marks on the mark tape 12, but the present invention is not limited to this, and a magnetoelectric transducer may be used as long as it does not affect the magnetic tape. The magnetic mark may also be read by

Further, in the above embodiment, a number of mark points corresponding to the types of tape times are printed on the mark tape 12, but the present invention is not limited to this, and may be encoded. .

Furthermore, in the above embodiment, the mark tape 12 is pasted on the side surface of the tape cassette 16, but the third
As shown by the broken line 12a in the figure, a mark tape may be pasted on the edge of the tape cassette 16 in alignment with the mark reading position of the magnetic recording/reproducing device.

Furthermore, although the present invention is configured such that a mark tape is pasted on an existing cassette tape, if the mark location is printed along with other symbols such as the manufacturing company name during the manufacturing stage of the cassette tape, the mark tape can be applied when used. There is no need to paste it.

Furthermore, although the present invention is configured to read the mark written on the tape cassette by some means, the magnetic recording/reproducing device is provided with a tape time manual setting means, and this is operated according to the type of cassette tape. It is also easy to preset the tape time in the time counter 9.

As explained above, the cassette tape remaining tape time display device according to the present invention is capable of displaying the tape remaining time of the cassette tape in units of seconds, and can grasp the tape remaining time extremely accurately. This makes it easy to judge whether one song can be completely recorded at the end, especially when the remaining tape capacity is extremely small.

Furthermore, once the mark tape is pasted on the tape cassette, it can be used semi-permanently, and the complexity of operation can be eliminated compared to the case where the tape time is manually set each time recording or playback is performed.

Furthermore, various effects can be achieved, such as requiring no modification to commonly available cassette tapes.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the remaining time display device for a cassette tape according to the present invention, and FIG. 2 is a perspective view showing an example of a mark tape used in the present invention. It is an explanatory diagram to explain. 2...Display switching circuit, 3...Decoder/driver circuit, 4...Display device, 8...
・Tape time setting section, 9... Tape time counter, 12... Mark tape, 14...
Marked location, 15...Cassette tape, 16.
...Tape cassette, 17...Photoelectric conversion element.

Claims (1)

[Claims] 1. A tape time setting unit that reads a recording time mark attached in advance to a predetermined location on a tape cassette and outputs a time preset signal specified by this mark, and a tape specified by a time preset signal from this tape time setting unit. A tape time counter in which a time is preset and the tape time is subtracted while the tape is running, a decoder/driver circuit that receives the time signal of this tape time counter as input, and an output of this decoder/driver circuit to determine the remaining amount of tape. A cassette tape remaining amount time display device consisting of a display device that digitally displays the time.