JP2689587B2 - Rotating head type magnetic recording / reproducing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head type magnetic recording / reproducing apparatus such as a video tape recorder or an audio tape recorder, and more particularly to a rotary head with a magnetic tape wound around it. Temporarily stop the rotation of the rotating drum,
When the rotary drum is driven again, the resistance between the magnetic tape wound around the rotary drum and the rotary drum is reduced so that the motor for driving the rotary drum can be started even if the starting torque is small. It is a thing.

2. Description of the Related Art An example of a conventional rotary head type magnetic recording / reproducing apparatus will be described with reference to FIG.

In the figure, 13 is a magnetic tape, a fixed drum 2 arranged on a substrate (not shown) and a rotary drum 4 incorporating a rotary head, and the magnetic tape 13 is wound around the rotary drum 4 at a predetermined winding angle. It moves while being restricted by the moving post 3 for winding only.

A tension is required for the magnetic tape 13 to travel stably while contacting the fixed post 2, the moving post 3, and the rotating drum 4, and in order to apply the tension to the magnetic tape 13, a pin 6 is attached to the base body. A tension arm 8 which is rotatably held by the one end thereof and has one end engaged with a spring 9 to have a turning force in the arrow direction is provided, and the tension post 1 provided at the other end of the tension arm 8 is provided.
Is always in elastic contact with the magnetic tape 13.

Further, the rotary drum 4 has a motor engaged with it.
The rotation is controlled by a control box 11 for controlling the rotation of the motor 17 and the motor 17, and a power switch 12 for closing the circuit thereof. Then, in the case of the recording standby and the reproduction pause, the progress of the magnetic tape 13 is stopped while the tension is applied to the magnetic tape 13 by the tension post 1 as shown in FIG.
Is kept rotating, but the rotating drum 4
Magnetic head (not shown) built in the disk and the magnetic tape
By repeating the contact of 13 at the same position, the magnetic powder coated on the magnetic tape 13 peels off and adheres to the magnetic head, which deteriorates the performance of the magnetic head. In order to prevent this, when the above state is continued for a certain period of time, the power switch 12 is opened by the command of the control box 11 and the rotation of the rotary drum 4 is stopped.

On the other hand, there is a case where the power switch 12 is intentionally opened in the state shown in FIG. 2 to stop the rotation of the rotary drum 4 for the purpose of reducing the power consumption even if the fixed time is not reached.

The rotating drum 4 stopped by the above-mentioned methods is configured to start rotating while the magnetic tape 13 is wound by closing the power switch 12 again.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described configuration, since the magnetic tape 13 that is still tensioned is wound around the stopped rotating drum 4, the magnetic tape 13 and the rotating drum 4 are
Since the outer periphery of the rotating drum 4 is in close contact with the rotating drum 4, the drive motor 17 needs a rotating torque required to separate the magnetic tape 13 from the outer periphery of the rotating drum 4 when the rotating drum 4 starts to rotate again. However, there is a problem in that the power consumption becomes large and the power consumption increases.

Means for Solving the Problems A rotary head type magnetic recording / reproducing apparatus of the present invention is configured such that a magnetic tape is wound around a rotary drum having a built-in rotary head at a predetermined angle, and the rotary head is provided with a tension post. A free tension arm is rotationally biased by a spring so that the tension post elastically contacts the magnetic tape, and a predetermined tape tension is applied to the magnetic tape, while the rotary drum rotates. In a rotary head type magnetic recording / reproducing apparatus for recording / reproducing information on / from the magnetic tape by the rotary head, the magnetic tape is wound around the rotary drum at a predetermined angle, and the tension post is in contact with the magnetic tape. Then, the rotation of the rotating drum and the running of the magnetic tape are stopped, and the rotating drum is restarted from the stopped state. At the time of start of rotation driving, the tension arm is forcibly forced against the rotational bias by the spring so that the tension post is separated from the magnetic tape prior to the rotation start of the rotary drum. After the rotary drum is rotated and started to rotate, the forcible force is released so that the tension post elastically contacts the magnetic tape by the biasing force of the spring.

Effect According to the above configuration, since the frictional resistance between the rotating drum and the magnetic tape is reduced by separating the outer circumference of the rotating drum from the magnetic tape, the motor for driving the rotating drum is started when the rotating drum is driven again. The rotation is started even if the torque is small, and the outer shape of the drive motor can be reduced accordingly.

Further, since the load on the drive motor is reduced, the power consumption of the drive motor can be reduced.

Embodiment FIG. 1 shows an embodiment of the rotary head type magnetic recording / reproducing apparatus of the present invention. The difference from the conventional configuration shown in FIG. The rotary drum 4 is stopped by opening the power switch 12, and when the rotary drum 4 is driven to rotate again, the tension post 1 is rotated in the direction of arrow a away from the magnetic tape 13 before the rotary drum 4 is rotated. The tension of 13 is released, the magnetic tape is in the state of the alternate long and short dash line 16, and the rotary drum 4 and the magnetic tape 16 are separated.

As a mechanism for rotating the tension post 1 in the direction of arrow a, a cam rotation motor 10 controlled by a control box 11 is engaged with a gear 5 with a cam having a cam groove 5a by a known coupling method to rotate the rotation. Before transmitting a signal for rotating the drum driving motor 17 again from the control box 11, a signal for rotating the cam rotation motor 10 is issued from the control box 11 to rotate the cam rotation motor 10. By doing so, the cam-equipped gear 5 rotates in the direction of arrow b by a predetermined angle until the tip of the cam groove 5a reaches the position of 14 shown by the alternate long and short dash line, and then stops.

The engagement pin 7 provided on the tension arm 8 follows the cam groove locus of the cam gear 5 so as to come into contact with the cam groove 5a of the cam gear 5 when the cam gear 5 rotates and stops. By moving to the position of 7a,
The tension arm 8 rotates about the pin 6 in the direction of arrow a and stops in the state of the tension post 1a.

In the above state, the tension of the magnetic tape 13 is released and becomes the state of the magnetic tape 16, and in this state, a signal for rotation is issued from the control box 11 to the rotary drum drive motor 17 to drive the rotary drum. motor
The rotation of 17 causes the rotary drum 4 to start rotating.

After the rotating drum 4 starts rotating, a signal for rotating the cam rotating motor 10 in the reverse direction is issued from the control box 11, whereby the cam rotating motor 10 rotates in the reverse direction, and The engaged gear 5 with cam rotates in the direction of arrow c and returns to its original state, and the tension arm also enters the state of the tension arm 8, and the tension post is applied by the rotational force applied by the spring 9. 1 applies tension to the magnetic tape 16 and returns to the state of the magnetic tape 13, so that the magnetic tape 13, the fixed post 2, the moving post 3, and the rotating drum 4
The contact with is resumed, and recording / playback is possible.

The tension arm 8 is for loading together with the moving post 3 from the tape cassette mounting position to the magnetic tape driving position, and the tension arm 8 is set by setting the cam portion shape and the rotation angle of the cam gear 5. It is well known that the loading operation is performed.

As described above, according to the present invention, since the starting torque of the rotary drum drive motor can be reduced by temporarily releasing the tension of the magnetic tape, the outer shape of the rotary drum drive motor can be miniaturized. In addition, it can be driven with a small torque, so that power consumption can be reduced. Further, since the tension is released by rotating the tension arm, the structure can be simple and inexpensive. Furthermore, in a circumferentially opposed motor (a rotor and a stator face each other in the circumferential direction of the rotary shaft) generally used as a rotary drum driving motor, it is possible to reduce torque fluctuation during rotation by lowering torque. Therefore, coking (noise caused by torque fluctuation) can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of relevant parts of a rotary head type magnetic recording / reproducing apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view of relevant parts of a conventional rotary head type magnetic recording / reproducing apparatus. 1 ... Tension post, 2 ... Fixed post, 3 ... Moving post, 4 ... Rotating drum, 5 ... Gear with cam, 5a ...
... Cam groove, 6 ... pin, 7 ... engaging pin, 8 ... tension arm, 9 ... spring, 10 ... cam rotation motor, 11 ...
… Control box, 12… Power switch, 13… Magnetic tape, 17… Rotary drum drive motor.

Claims (1)

(57) [Claims] 1. A rotatable drum having a rotary head built-in, wherein a magnetic tape is run while being wound at a predetermined angle, and a rotatable tension arm having a tension post at one end is attached to the magnetic tape. Rotation is urged by a spring so as to elastically contact with the magnetic tape, and rotation of the rotary head records and reproduces information on the magnetic tape as the rotary drum rotates while applying a predetermined tape tension to the magnetic tape. In a head type magnetic recording / reproducing apparatus, the rotation of the rotating drum and the running of the magnetic tape are stopped while the magnetic tape is wound around the rotating drum at a predetermined angle and the tension posts are in contact with the magnetic tape. At the start, when the rotary drum is driven to rotate again from the stopped state, the rotary drum is started in rotation. Then, the tension arm is forcibly rotated against the rotational bias by the spring by a force so that the tension post is separated from the magnetic tape, and after the rotary drum is rotationally activated, A rotary head type magnetic recording / reproducing apparatus, wherein the tension post is elastically brought into contact with the magnetic tape by an urging force of the spring by releasing the forcing force.