JPS5913094B2 - Tape guide opening/closing mechanism of magnetic recording/reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing device, and more particularly to a tape guide opening/closing mechanism for opening and closing a gap between a tape guide and a rotary head in two different modes in a width direction scanning rotary head recording device. It is something.

2. Description of the Related Art Hitherto, width direction scanning rotary head recording devices have been widely used in broadcast VTR devices and home VTR devices.

By the way, in this type of VTR device, when passing a magnetic tape between a rotating head and a tape guide, a rotary solenoid is used to move the tape guide away from the rotating head, the magnetic tape is manually threaded, and recording and playback operations are performed. When stopping temporarily, the same mechanism moves the tape guide away from the rotating head to avoid long-term contact between the magnetic tape and the rotating head 10. However, when the width direction scanning rotary head recording device is used as a magnetic tape device for an electronic computer, it is necessary to thread the magnetic tape automatically rather than manually. In this case, since the magnetic tape is transported by an air stream, the tape guide must be placed at a sufficient distance from the rotary head, e.g. 15T.
frrfL I have to say more. In addition, even if the device stops recording and reproducing operations in a samurai manner while it is operating,
To avoid meaningless continuous scanning by the rotating head, it is desirable to keep the magnetic tape away from the rotating head. However, in this case, in order to shorten the response time of the device to the next recording/reproduction command, it is necessary to minimize the distance the tape guide is moved away from and to shorten the opening/closing time of the guide as much as possible. However, the conventional tape guide opening/closing mechanism has
There was no one that could realize these two operations with different characteristics. The present invention has been made in view of the above-mentioned circumstances, and is configured to ensure that large and slow opening/closing operations and small, high-speed opening/closing operations of the tape guide can be performed reliably without mutual interference. It provides a tape guide opening/closing mechanism for magnetic recording and reproducing devices, and its characteristics are that the tape guide fixed to the rotating shaft is opened and closed in a large and slow manner by a motor with a reduction gear, and by a solenoid. This is because the tape guide is small and can be opened and closed 35 at high speed. Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a perspective view showing an embodiment of the tape guide opening/closing mechanism according to the present invention, and FIG. 2 is a plan view of the main part of the mechanism.

In these figures, 1 is a rotary head disposed on the circumferential surface of a motorized spindle 2 and driven to rotate; 3 is a tape guide disposed corresponding to the rotary head 1; one end of this tape guide 3 is rotatable; Fixed to the shaft 4 and rotating head 1
A tape guide surface 5 is formed with an arcuate recess on the front end surface facing the tape guide surface 5 for supporting and guiding a magnetic tape (not shown) in an arcuate manner.
It consists of Reference numeral 6 denotes a motor that rotates the tape guide 3 to open and close the gap between the rotary head 1 and the tape guide surface 5. A motor 6 is provided between the output shaft of the motor 6 and the rotary shaft 4 to reduce the rotation of the motor 6. A reduction gear 7 is interposed to increase the rotational torque.

The rotating shaft 4 is rotatably supported by a support member 8 via a bearing (not shown), and inside the support member 8 there is a mainspring serving as a spring mechanism that constantly biases the tape guide 3 in one direction of the rotating head. A spring 9 is housed. The support member 8 is fixed to the mounting base 10 together with the spindle 2. A bent portion 10A is provided at the upper end of the mounting base 10, and is bent horizontally in the direction of the tape guide 3 and extends above the rotary head 1. has a pair of left and right protrusions 11 and 12.
is installed protrudingly.

These pair of protrusions 11 and 12 constitute a reference surface for positioning the other end of the tape guide 3 during recording and reproduction, and the protrusion amount of each protrusion 11 and 12 is set to be the same. In addition, as shown in FIG.
, 12 are provided with protrusions 13a and 13b, which constitute a positioning surface. A push-pull type solenoid 14 is disposed on the back side of the bent portion 10A of the mounting base 10 in correspondence with the surface 3a of the tape guide 3. This solenoid 14 rotates the tape guide 3 in a small amount independently of the motor 6 to open and close the gap between the rotary head 1 and the tape guide surface 5, and the base end of a pin 15 is connected to the movable part of the solenoid 14. has been done. The pin 15 is slidably inserted into a through hole 16 formed in the bent portion 10A of the mounting base 10, and its tip protrudes from the tip surface 10a. This pin 15 is located between the pair of protrusions 11 and 12, and a protrusion 17 is provided to protrude from the surface 3a of the tape guide 3 in correspondence with this pin 15. This protrusion 17 is formed in the same manner as the pair of protrusions 13a and 13b, and constitutes a positioning surface. Incidentally, FIG. 1 shows a state in which a magnetic tape (not shown) is threaded between a rotary head 1 and a tape guide 3, so that the tape guide 3 is moved far away from the rotary head 1.

This large opening/closing operation is performed by transmitting the rotation of the motor 6 to the rotating shaft 4 via the reduction gear 7. In this case, the reduction gear 7 has the function of amplifying the rotational torque of the small motor 6 and slowing down the large opening/closing operation. In particular, during the closing operation of the tape guide 3, the motor input line is short-circuited through an appropriate resistance to make the closing operation speed slower than that during the opening operation, and the tape guide 3 is connected to the pin 11 as a reference surface. It can soften the impact when hitting 12. Next, when the magnetic tape is being threaded and the apparatus is in operation, the solenoid 14 is driven when the recording/reproducing operation is temporarily stopped and the tape guide 3 is slightly moved away from the rotary head 1.

FIG. 2 shows such minute opening and closing operations of the tape guide 3. Normally, when the rotary head 1 is performing a recording/reproducing operation, the force of the mainspring spring 9 causes the protrusion 13 to open and close.
a, 13b, 17 are protrusions 11, 12 and pin 15, respectively
As a result, the gap between the tape guide surface 5 of the tape guide 3 and the rotary head 1 is maintained at a predetermined value. In this state, when the recording/reproducing operation is temporarily stopped, the solenoid 14 is simultaneously driven and the protrusion 17 is pressed to move the pin 15 in the direction of the tape guide 3 as shown in FIG. Rotate counterclockwise in FIG. 1 against the force of the spring 9 to move the tape guide surface 5 away from the rotary head 1. This tape guide surface 5
Since it is sufficient to move the distance away by a small amount of about 0.2 to 0.3 wn, the rotation angle of the rotating shaft 4 due to this operation is extremely small and can be kept within the range of the backlash of the reduction gear 7. Therefore, such minute opening/closing operations of the tape guide 3 can be performed without any interference with the motor 6 used for large opening/closing operations. Therefore, it is possible to suppress the opening/closing time to several Ms or less. Although the above embodiments have been described using a mainspring spring as the spring mechanism, the present invention is not limited to this in any way, and it goes without saying that leaf springs, torsion coil springs, etc. may also be used. be.

Furthermore, it is clear that the present invention is not limited to the opening/closing operation of a tape guide in a magnetic recording/reproducing device, but can be widely used in general mechanisms requiring slow large rotations and high speed minute rotations.

As explained above, the tape guide opening/closing mechanism of the magnetic recording/reproducing apparatus according to the present invention constantly biases the tape guide fixed to the rotating shaft in the direction of the rotating head using the spring mechanism, and decelerates the rotating shaft using the motor. The tape guide is connected via a gear, and a solenoid is provided corresponding to the tape guide, and the motor and solenoid are selectively driven. Therefore, the tape guide can be driven very slowly without mutual interference between the motor and the solenoid. It can be opened and closed, or opened and closed minutely at high speed. In addition, its effects are very large, such as a simple structure and reliable operation.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a tape guide opening/closing mechanism of a magnetic recording/reproducing apparatus according to the present invention, and FIG. 2 is a plan view of a main part of the same mechanism. 1... Rotating head, 3... Tape guide, 4... Rotating shaft, 5... Tape guide surface, 6... Motor, 7...Reduction gear,
11, 12... Protrusion (reference surface), 14...
...Solenoid, 15...pin.

Claims (1)

[Claims] 1. A tape guide with one end fixed to a rotating shaft, a reference surface for positioning the other end of the tape guide, a spring mechanism for pressing the tape guide against the reference surface, and a spring mechanism for rotating the rotating shaft and other parts of the tape guide. The tape guide is characterized by being comprised of a motor that opens and closes the end of the tape guide in a large manner relative to a reference surface, and a solenoid that slightly opens and closes the other end of the tape guide relative to the reference surface at a speed greater than the speed at which the tape guide is opened and closed in a large manner. Tape guide opening/closing mechanism for magnetic recording and reproducing devices.