JPS62154355A - Reel drive device - Google Patents

Abstract

PURPOSE:To eliminate an abrupt change in a tape state and to stop the tape while its tension is kept constant by controlling and stopping a reel drive means from information on stop and control corresponding to the tape winding diameter of a winding reel. CONSTITUTION:A travel speed information V on a mode instructing circuit 7 in a travel mode as well as a comparison signal (a) and a reference pulse (b) is supplied to a frequency and winding diameter converter circuit 6 from a tape speed information generator circuit 8. Through the use of an inputted information signal, the supplied information is outputted as a tape winding diameter information signal (rt), and inputted to a memory circuit 9 and a winding diameter/torque converter circuit 10 to calculate an appropriate torque value Tp in each travel. When a memory circuit 9 designates the tape winding diameter information (rt) as an address and inputs a read trigger, it outputs an appropriate torque value Ts at the time of stopping the tape travel. An appropriate torque value information signal Tp in tape travel is outputted from a switch circuit 11, while at the time of stopping the tape travel, the appropriate torque value information signal Ts is outputted. Then a reel motor drive circuit 14 controls a motor 15 so that torque in accordance with the appropriate torque value information signal can be generated in the motor 15 in the direction reverse to the rotating direction of a winding side reel receiving stand 1.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a reel drive device in a mechanism that has running modes with different running speeds and runs a tape-like body between two reels according to the running mode. It is related to.

[Conventional technology]

Conventionally, in a mechanism for running a tape-like object between two reels, for example, a so-called direct drive tape-like object is used, in which a take-up reel holder and a supply-side reel holder are each directly driven by separate motors. In the case of a recording/reproducing device having a running mechanism, when the tape-like object stops running, the rotation of the capstan and pinch roller for transporting the tape-like object is stopped, and a constant reverse torque is applied to the drive motor of the take-up reel, etc. was generated and braked the rotation of the reel.

[Problem that the invention seeks to solve]

In these conventional systems, the braking force is not controlled according to the rotational state of the reel, and the rotational state of the reel changes moment by moment according to the amount of tape-like material wound on the reel. Since the rotation of the reel was braked by generating a certain amount of reverse torque in the reel's rotational drive means, sudden braking was applied, especially when the reel was rotating at high speed, resulting in the inertia of the reel or the impact of the braking. This can cause damage to the tape-like material wound on the reel, such as elongation or loosening. For example, in recording and reproducing devices, it is necessary to reduce the thickness of the tape-like material in order to record and play over a long period of time. It was an obstacle to the attempt.

In addition, as mentioned above, when the tape is stopped, the tension of the tape changes, so the contact of the recording/playback head to the tape also changes, causing problems such as wear of the recording/playback head. was occurring.

The present invention has been made in view of the above circumstances, and has a simple structure that eliminates sudden changes in the tape-like body when the tape-like body stops running and allows the tape-like body to stop while keeping the tension constant. The purpose of this invention is to provide a reel drive device that can.

[Means to solve the problem]

The reel driving device of the present invention includes a reel driving means for driving a take-up reel, a winding diameter information generating means for generating winding diameter information of a tape-like body on the winding reel, and stop control information according to the winding diameter information. and stop control means for controlling the reel driving means in accordance with stop control information held in the holding means.

[Operation] According to the above-described configuration, the reel driving means can be controlled and stopped using stop control information corresponding to the winding diameter of the tape-like body of the take-up reel at the time of stopping.

〔Example〕

The present invention will be explained below based on examples.

FIG. 1 is a schematic diagram showing an embodiment of the present invention in which the present invention is applied to a tape running stop mechanism for a VTR using a direct drive system that directly drives reel holders on the winding side and the supply side, respectively.

FIG. 2 is a timing chart when period data corresponding to the rotation period of the reel pedestal is measured in FIG. 1 above.

FIG. 3 is a diagram showing the relationship between the tape winding diameter and torque on the take-up reel in each running mode of FIG. 1.

In FIG. 1, a fixed pickup head 2 with a plurality of small pieces of magnets etc. attached at equal intervals is installed on the circumference of the reel holder 1 on the winding side, and the output thereof is inputted to the comparison signal generation circuit 3. As a result, a signal corresponding to the rotation period of the reel pedestal 1 as shown in FIG. 2(a) is outputted from the comparison signal generator 3 and inputted to the period measuring circuit 4.

The period measuring circuit 4 is connected to the reference pulse generator 5 as shown in FIG.
A reference pulse set to a sufficiently higher frequency than the comparison signal (a) as shown in b) is input, and the period measuring circuit 4 counts the number of pulses of this reference pulse Φ). Periodic data t as shown in (C1) to (C4)
It is input to the period/winding diameter conversion circuit 6 as follows.

Further, the tape running speed information V in the tape running mode instructed by the mode instruction circuit 7 is supplied to the period/winding diameter conversion circuit 6 from the tape speed information generating circuit 8, and the period/winding diameter conversion circuit 6 is supplied with tape running speed information V in the tape running mode instructed by the mode instruction circuit 7. The circuit 6 uses these input information signals to calculate the winding diameter r of the tape wound on the take-up reel based on the relational expression r=V-1/2π, and calculates the result on the take-up reel. Tape winding diameter information signal rt
Output as .

The output of the period/winding diameter conversion circuit 6 is the memory circuit 9 and the winding diameter φ.
Torque conversion circuit 10Vc is input.

The tape winding diameter information signal rt of the width strip 1j and the tape running speed information signal are input to the winding diameter-torque conversion circuit 10. *Based on the information, the appropriate torque +='rpv for each time the tape runs is calculated and output as an appropriate torque value information signal.

Further, the memory circuit 9 stores in advance appropriate torque value information Ts at the time of tape running stop corresponding to the tape winding diameter information signal rt of the winding side reel as shown in FIG. Information rt is specified as an address,
When the read trigger is input, the appropriate torque value T3 at the time when tape running is stopped is output as an appropriate torque value information signal.

In FIG. 3, a indicates the relationship between the winding diameter of the tape on the take-up reel and the appropriate torque value information Ts during fast forwarding, b during normal playback or recording, and C during half-winding. The memory circuit 9 divides the area in which data is stored according to the tape running mode, and after specifying the area according to the mode of the speed information V based on the tape running speed information signal VIC, the data is inputted. An address corresponding to the winding diameter information signal rt of the tape on the take-up reel is specified, and information on the appropriate torque value Ts is output.

The outputs of the memory circuit 9 and the winding diameter/torque conversion circuit 10 are input to a switch circuit 11. The switch operation of the switch circuit 11 is such that when the mode instruction circuit 7 instructs the tape stop mode, the timer operation control circuit 12 detects the stop instruction signal and outputs a timer operation signal for operating the timer circuit 13.

The timer circuit 13 receives the operation signal from the timer operation control circuit 12 and connects the switch circuit 11 to the H side shown in the figure until the tape tension is stabilized after the operation mode is switched and the operation signal is set in advance. After a predetermined period of time has elapsed, the connection is made again to the L side. Note that for a predetermined period of time preset by the timer circuit 13, the tape tension remains stable after the operation mode is switched.
This period can be set by selecting the time set for each running mode depending on the switching pattern of the running mode, or by changing the tape tension state and reel holder without using a timer circuit. This can also be realized by switching the connection of the switch circuit 11 by detecting the state of the rotational speed of the drive motor or capstan motor, etc., and detecting whether or not they have reached a stable state. When used, the accuracy of tape tension control is further improved.

Further, the switching signal of the switch circuit 11 output from the timer circuit 13 is also input to the memory circuit 9. The signal serves as a trigger for reading data stored in the memory circuit 9, and reads out the data specified by the address corresponding to the tape winding diameter information signal rt of the winding reel.

As a result of the above operations, when the tape is running, the switch circuit 11 outputs the appropriate torque value information signal Tp from the winding diameter/torque conversion circuit 10 when the tape is running, and when the tape is stopped, the memory circuit 9 outputs the appropriate torque value information signal Tp when the tape is stopped. A value information signal Ts is output. The reel motor drive circuit 14 controls the motor 15 to generate torque in accordance with the appropriate torque value information signal in a direction opposite to the rotational direction of the take-up value reel holder 1, thereby controlling the take-up time (not shown). By controlling the amount of tape wound on the side reel, the tape tension can be kept constant and tape running can be stopped without adversely affecting the tape.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to eliminate sudden changes in the tape-like body when the tape-like body stops running with a simple structure, and to stop the tape-like body while keeping the tension constant. It is possible to provide a reel drive device that can

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention in which the present invention is applied to a tape running stop mechanism of a VTR using a direct drive system in which a reel holder on the winding side is directly driven. FIG. 2 is a timing chart when period data corresponding to the rotation period of the reel pedestal is measured in FIG. 1 above. FIG. 3 is a diagram showing the relationship between the winding diameter of the tape on the take-up reel and the appropriate torque value in each running mode of FIG. 1.

Claims (1)

[Claims] A reel driving means for driving a take-up reel, a winding diameter information generating means for generating winding diameter information of a tape-like body on the winding reel, a holding means for holding stop control information corresponding to the winding diameter information, and A reel drive device comprising: stop control means for controlling the reel drive means according to stop control information held in a holding means.