JPS5916183A - Auto-stop device of tape recorder - Google Patents

Abstract

PURPOSE:To stop the tape running in an optional position proportional to the tape remaining time at a fast-forwarding time and a rewinding time, by detecting a reel rotation signal proportional to the rotation of a supply reel. CONSTITUTION:A revolving reflective plate 2 which rotates in accordance with a reel disc 1 is provided with slits 2a, and the quantity of light changing in accordance with the rotation is converted to a voltage by a reflective phototransistor 3 to generate the reel rotation signal. The tape remaining time is calculated in an operating part 7 by a counter 5, which detects a rotation cycle from the reel rotation signal, and a tape counter 6 which detects the number of revolution. When the tape remaining time in a tape position where the tape running should be stopped is inputted from a key input circuit 11, it is stored in a storage circuit 8B and is outputted to a comparing circuit 9. The tape remaining time outputted at any time from the operating part 7 is stored in a storage circuit 8A and is outputted to the comparing circuit 9, and both tape remaining times are compared with each other; and when they coincide with each other, a tape running stop signal is outputted to a stop mechanism 10.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an auto-stop device for a cheap recorder that stops tape running at an arbitrary position relative to the remaining tape time during fast forwarding or rewinding, for example in a video cheap recorder. be.

Conventional configuration and its problems In a video tape recorder (hereinafter referred to as VTR), when video information is recorded on a tape cassette, it is possible to record 30 minutes before, 1 hour before, 30 minutes after, or 1 hour from an arbitrary tape position. There is a desire to know what kind of video information is stored at the later tape position.

On the other hand, in current VTRs, the tape position is recognized by the count value of a tape counter that counts according to the number of rotations of the reel during fast forwarding (hereinafter referred to as FF), rewinding (hereinafter referred to as REW), and sometimes the tape position is recognized and the tape is moved. Let me stop it. However, when using a tape counter, the exact tape position cannot be determined directly from the count value. This is because the count value of the tape counter corresponds to the number of rotations of the reel and becomes the t value, so depending on the tape winding diameter (for example, the first winding diameter and the last winding diameter), It is fast forwarded to I/1 rotation. Another reason is that the tape base to be rewound has a large width. For this reason, it was not possible to recognize the exact position of the tape based on the count value and stop the tape from running.

Purpose of the Invention The present invention has been made to solve the problems as described above.
The object of the present invention is to use a small and simple structure to stop tape running at any desired tape position corresponding to the remaining tape time.

Structure of the Invention In order to achieve the above object, the present invention provides a means for detecting a t-reel rotation signal which is proportional to the rotation of the supply reel, and a means for counting the number of rotations of 1μ from the above-mentioned Lee/L/rotation signal. a tape counter; and means for detecting a reel rotation period from the reel rotation signal.

a calculation unit that calculates the remaining tape time from the rotation period and the number of rotations; a storage circuit that stores the remaining tape time or the change time of the remaining tape time; and a comparison circuit that compares the remaining tape time or the change time of the remaining tape time. , when fast forwarding and rewinding I
It is equipped with a 7-turn mechanism for controlling the ζ-chie to run at 7°, and makes it possible to stop the tape running at a tape position corresponding to any preset tape remaining time during fast forwarding and rewinding.

DESCRIPTION OF EMBODIMENTS An example in which the present invention is implemented in an auto-stop device for a VTR will be described below with reference to the drawings. FIG. 1 shows a +J-le rotation signal detector, which is composed of a reel stand (1), a one-rotation reflector <2+, and a reflective phototransistor (3). When the reel stand (1) rotates, the reflection plate (2) also rotates in conjunction with the reel stand (1). This rotating reflector (2) has
Since the slit (2a) shown in Fig. 2 is provided, the amount of light input to the 1 reflective phototransistor (8) increases or decreases as the reel stand rotates.
Stiff. This changing light beam is converted into voltage to generate a reel rotation signal proportional to the rotation of the reel 8(1).

Next, according to the basic configuration diagram shown in Fig. 8, FF, RE
The auto-stop device in W will be explained in principle. In Figure 8, (4N;! Lee yv rotation signal detector, (5) is a counter that detects the rotation period from the reel rotation signal, (6)
is a tape counter that detects the rotation speed from the reel rotation signal, (7) is an arithmetic unit that calculates the remaining tape time from the rotation period and rotation speed, and (8) stores the remaining tape time or the change time of the remaining tape time. memory circuit.

(9) is a comparison circuit that compares the remaining tape time or the change time of the remaining tape time, and C1 [) is a knob mechanism that stops the tape running corresponding to one remaining tape time.

The rotation period detection counter (5) is a counter that detects the rotation period by counting reference pulses during one rotation of the reel based on the reel rotation signal.

Rotation speed detection tape counter (6).

This is a tape counter that detects the number of rotations by counting reel rotation signals.

Next, the calculation principle of the calculation section (7) for calculating the remaining tape time will be described. First, as a first step, the remaining tape time at an arbitrary tape position when the tape linear movement speed is constant is calculated.

The length of the tape wound on the supply reel is e.

The tape thickness is s, and the reel diameter including the thickness of the tape wound on the supply reel, that is, the diameter of one roll.

Let the diameter of the hub be d.

π 11-- CD"-d") ・
g) Denoted by s. Here, the relationship between the reel rotational angular speed ω and the tape linear movement speed V is p-2v-...(2) ω Also, the relationship between the rotation period Tw and the rotational angular speed ω when the tape linear movement speed is constant is 1r Tw family -... (3) Therefore, the relationship between D and Tw is D - - Tw (4) π Formula (Substituting 4 into formula (1).

e w=7-;((-;;Tw)2-d")
・(51 step direct tightening movement speed rgL (playback,
Since (constant during recording) ■ is constant, the remaining time on the tape is ""-1--Tw"-4vs"
”'(6)4π8 In this way, when the tape linear movement speed is constant, that is, playback,
When recording, etc., when the hub diameter d is known and the tape' thickness S is constant, it is possible to calculate the tape remaining time I'1Jto by detecting one rotation period Tw.

Next, in the second step, the remaining time of the tape at an arbitrary tape position is calculated when the tape linear movement speed is undefined, that is, when the tape is at FF or REW%.

The remaining tape time to be sought is tn, which is obtained in the first step and the remaining tape time is t. , summerize the remaining tape time of to and to △ [and 1 is tn t 1 o ± △ t...(7)
(However, it is indicated by +REW direction, -FF direction).

Δt was fed from the tape position to to the tape position [n. Or a rewound tape.

Proportional to total △e. Let the tape winding diameter of the supply reel at the time of to, and let n be the number of revolutions of the supply reel from t to the tape position of tfl, then △e is πD + π
(D −2s ) Rewriting equation (8).

Also, D is t. D=-T due to rotation period Tw at time
w...C1[)π Equation (IG is substituted into Equation (September), and Equation Qη is divided by the tape linear movement speed V at the time of calculating to, △
t is found.

If equation (2) is rewritten as a recurrence equation, the FF direction △(tΣ △tn...(2
) xl According to the REW direction, when the tape linear movement speed is not constant, the tape remaining time when the tape linear movement speed is constant is calculated. Based on the rotation period, the tape position (fixed By detecting the number of revolutions at which the reel rotates from the rotation period during fast running (i.e., the tape position where the tape winding diameter is known), the remaining time of the tape at a given tape position can be calculated.

Next, FIG. 4 shows an example of a configuration in which the present invention is carried out using a microcomputer or the like. In Figure 4, (
4) is a reel rotation signal 8 detector, (5) is a counter that detects the rotation period from the reel rotation signal, (6) is a chi 1 counter that detects the rotation number from the beam 1 μ rotation signal, and (7) is the rotation period. A calculation unit that calculates the remaining tape time from the rotation speed,
(8A) is a first storage circuit that stores the remaining tape time or the change time of the tape remaining time; (9] is a comparison circuit that compares the change time of the remaining tape time or the remaining tape time;
0 (J is a stop mechanism that stops tape running according to the remaining time of 5--7 degrees.

(B) is a key input circuit for inputting the preset remaining tape time or change time of the remaining tape time; (8B) is input from the key input circuit ap and stores the change time of the remaining tape time or the remaining time of the tape; a second memory circuit to
Nomote information such as Ml, IFF, REW, PLAY is sent from the VTR to the microcomputer's rotation period detection counter (5), remaining tape time calculation section (7), and comparison circuit (9).
This figure shows the mode input circuit for inputting to the file.

First of all, number 1. The case where the remaining tape time is stored in the second storage circuit (8A) (sB) will be described. In this case, the remaining tape time at the tape position at which the tape is to be stopped is input in advance from the key input circuit a to the second memory circuit (8B). Second
The storage circuit (8B) stores the input remaining tape time and outputs it to the comparison circuit (9). on the other hand.

The first storage circuit (8A) stores the remaining tape time which is outputted from the arithmetic unit (7) at any time, and outputs it to the comparison circuit (9). Comparison circuit (1st and 2nd memory circuit (8A) in Shun)
The remaining tape time output from (8B) is compared, and if they match, a tape running stop signal is output to Nutop S structure C1O.

Next, the first. A case will be described in which the change time of the remaining tape time is stored in the second storage circuits (8A) (8B).

In this case, tco data is recorded in the second storage circuit (8B) by setting the time to 10 minutes, 80 minutes, 1 hour, etc. in advance. A key switch corresponding to this data is prepared from the key input circuit QU so that the user can select it according to the situation. - 10,000, in the first memory circuit (8A).

Calculation unit (7) when the key is manually input from the key input circuit Oυ
The change time of the remaining tape time outputted from the t-tape is stored as a reference change time, and the difference between the change time of the remaining tape time output from the arithmetic unit (7) and the reference change time is calculated from time to time, and the comparison circuit (9) Kairu Heda. The comparison circuit (9) compares the difference between the data output from the second memory circuit (8B) to the key input circuit (b) and the reference change time output from the first memory circuit (8A). death.

If they match, a stop mechanism (10) outputs a running stop signal.

Next, the stop mechanism is similar to that currently provided in VTRs. That is, it is a stop mechanism that receives the tape running stop signal outputted from the comparator circuit +9 as an input signal and stops the tape running.

Finally, (b) is FF from the VTR body, REV
This is a mode input circuit that inputs mode information such as , PLAY, etc.

The rotation period detection counter (5) and calculation unit (7) are manually inputted with mode information indicating whether or not the linear movement speed is in a constant mode, and the comparison circuit (9) is inputted to the rotation period detection counter (5) and calculation unit (7), and the comparison circuit (9) inputs mode information indicating whether or not the linear movement speed is in a constant mode. Entering mode information. Comparison circuit (91
The tape running stop signal is not output in modes other than TECH, FF, and REW modes.

In the above-described embodiment, the remaining tape time may be displayed as a tape address indicating the tape position, and in this case, a tape address counter that can be displayed in all modes such as FF and REW can be obtained.

As described above, according to the present invention, with a simple configuration, it is possible to stop the running of the tape at any tape position corresponding to the remaining time of the tape. This is extremely useful because it allows you to quickly and accurately know what information will be stored at the tape position after a minute or an hour without any troublesome effort.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a reel rotation signal detector, Fig. 2 is a bottom view of a reflector used in the detector, Fig. 3 is a basic block diagram of the present invention, and Fig. 4 is an embodiment of the present invention. FIG. (4)... Reel rotation signal detector, (5)... Rotation period detection counter, (6)... Rotation number detection tape counter, (7) =-. Tape remaining υ time calculation section, (8)...Storage circuit, (8A
) (8B)...first and second memory circuits, (9)...
・Comparison circuit, 4... Stop mechanism, 0υ... Key input circuit, (2)... Mode input circuit agent Yoshihiro Morimoto Figure 1 Exit - 3 Figure 2

Claims (1)

[Scope of Claims] 1. A means for detecting a reel rotation signal proportional to the rotation of the supply reel, a tape counter for counting the number of reel rotations from a predistributed 1 μ rotation signal, and a tape counter for counting the number of reel rotations from the reel rotation signal. A means for detecting a rotation period, and a calculation section for calculating remaining tape time from one rotation period and the number of rotations. Equipped with a memory circuit that records the time of change in the remaining tape time or the remaining tape time, a comparison circuit that compares the remaining tape time or the change time in the remaining tape time, and a stop mechanism that stops the tape from running when fast forwarding or rewinding. This auto-stop device for a 7° recorder is characterized in that it is possible to stop the running of the tape at a preset position corresponding to an arbitrary tape remaining time during fast forwarding and rewinding. 2. The comparison circuit includes a first storage circuit that stores the remaining tape time or a change time of the remaining tape time, and a second storage circuit that stores an arbitrary remaining tape time or a change time of the remaining tape time set in advance. Compare the outputs and select the first. An auto-stop device for a tape recorder as set forth in claim 1, characterized in that the output of the second memory circuit matches each time t, and the stop mechanism is configured to input a nutotuba signal for controlling the running of the tape recorder. . 8. In the calculation of the calculation section that calculates the remaining tape time (Al
tn -KI TV'' -Kp However, [0: Remaining tape time 'l'w: Supply side -μ rotation period when calculating to tn: Remaining tape time after supply side reel n rotation △ [n: Supply side reel Tates in one rotation.The remaining time changes from 4. to 21 to 3' sign of constant (B) formula: +REW direction, -FF direction (At
(The auto-stop device for a tape recorder according to claim 1, characterized in that a B1 type is used.