JPS6117256A - Magnetic tape drawing-out device - Google Patents

Abstract

PURPOSE:To rotate a magnetic tape at a high speed by constituting an inside contact surface of a fixed bearing member so that a hollow shaft which has been pressed into a roller is rotated. CONSTITUTION:Before a magnetic tape is drawn out, the magnetic tape and a roller 33 are in a non-contact state. Subsequently, a holder 30 connected by a male screw 36a provided on a bearing member holding member 36 is moved, the roller 33 contacts the tape thereby, the tape is drawn out of a cassette, brought into contact with a head, and a signal is recorded or reproduced. In this case, as the tape runs, the roller in contact with the tape receives a frictional force, and a hollow shaft 34 is pressed into the roller 33. In this way, both of them are unified, and rotated on the inside contact surface of oil impregnation metals 32, 35 functioning as the bearing members held by the bearing member holding members 31, 36 connected and held by a center shaft 37 which is not of contact with the hollow shaft 34.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic tape drawer for use in a magnetic recording/reproducing device such as a cassette video tape recorder.

Structure of a conventional example and its problems Hereinafter, a conventional magnetic tape drawer will be described with reference to the drawings. FIG. 1 is a schematic diagram of a magnetic recording and reproducing apparatus having a conventional magnetic tape pull-out device. In the figure, 1 is a chassis, and 2 is a cassette having a supply reel 3 and a take-up reel 4.

The magnetic tape 5 wound around the supply reel 3 passes through the guide post 7 and the guide post 8 to exit the cassette 2, and then passes through the tension post 9, the erase head 10, the impedance roller 11, the guide post 12, and the guide post 13. It wraps around the rotating head cylinder 14, passes through the guide posts 15 and 16, the impedance roller 18, the audio/control head 19, the guide post 20, the capstan 22, the pinch rope 21, and enters the cassette 2, passing through the guide post in the cassette. 6 C take-up reel 4
It is wound up.

The dashed line 17a is a trajectory from the position 122L, 13& when the guide post 12.13 is at the cassette opening to the predetermined winding position.

The dashed-dotted line 1 is also the locus of the guide post 15 and 16.

Here, attention is paid to the guide posts 12', 13, 115, and 16. FIG. 2 is a partially enlarged perspective view of the guide post 16.16. The holder 30 has a post part 30& and 30b.
There is. A guide post 15 having a slightly pointed tip is implanted in the boss portion 30b, and a lock post 166 is implanted in the boss portion 30&.

FIG. 3 is a partial cross-sectional view of the vicinity of the lock post 16e.

The lock post 16el installed in the boss portion 30a has a
One end is provided with an external threaded portion to engage with a male threaded portion provided on the lower horn j6d of the guide post 16, and the other end of the lock post 16el is provided with a male threaded portion provided on the lower horn j6d of the guide post 16.
It has a cylindrical hole provided to engage with f. The center shaft 16f, the upper collar 16b, and the lower collar 16d are press-fitted together. The upper end of the upper collar 16b has a groove 16C (G)
Ru.

16a is a resin roller generally made of Duracon resin, and is configured to rotate around a central axis 1sf. The magnetic tape 5 is in contact with the roller 16a during or when the tape is being drawn out, and the upper collar 16b is in contact with the magnetic tape 5.
and is regulated by lower horn 16d. Upper brim 16b
When you hook a screwdriver or other jig to the a16c and rotate it around the central axis 16f, the lower part /16d
By engaging the male thread of the lock post 168 with the female thread of the lock post 168, the upper collar 1sb, roller 161L, and lower horn (16d) can be moved up and down relative to the lock post 16e.

The conventional magnetic tape pull-out device configured as described above is a very small post unit and is capable of vertically regulating and vertically adjusting the magnetic tape.

“However, the above configuration has the following drawbacks.

(1) When the rollers are rotated at high speed, there are ``cues'' and ``bees'' that can be discerned even during normal use.

An abnormal, harsh sound that sounds like a cackle may occur.

(2) When the roller is rotated at high speed, the play between the roller and the rotating shaft increases, and for example, the initial runout of a few micrometers becomes tens of micrometers, causing a shake in recorded and reproduced images. This results in an increase in so-called jitter, which has a serious impact on image quality.

From the above, in a roller unit with such a simple structure, it is possible to move the magnetic tape at high speed, such as fast forwarding or rewinding, with the magnetic tape in contact with the roller while the magnetic tape is pulled out. It has become impossible to do so.

Additionally, in order to achieve this, there was a structure in which ball bearings were embedded in the rollers, which solved the above-mentioned drawbacks, but from a cost perspective, this was extremely expensive. It had the serious drawback of becoming

In addition, Figure 4 shows the guide post 1 that was conventionally considered.
FIG. 6 is a cross-sectional view of an improvement plan of No. 6. The one shown in the figure has a structure in which an oil-impregnated metal 40, 43 is press-fitted into the inner circumference of a hollow vibrator 39 made of resin such as Duracon, and when the roller 39 rotates due to the movement of the magnetic tape,
Since the oil-impregnated metal 40.43 that is integrated with the
The contact surface of the oil-impregnated metal 40, 43 with the rotating support shaft 42 constantly changes due to the rotating ship, so there is no so-called conforming effect, and the rotational vibration increases and may become a source of vibration for the magnetic tape. . In addition, Nishiki is shown in Figure 4.

41 is a bearing member holding member corresponding to the upper collar 16b and lower collar 16d in FIGS. 2 and 3, respectively.

OBJECTS OF THE INVENTION An object of the present invention is to provide a magnetic tape having simple, inexpensive, and high-performance rollers, which allows a magnetic tape to be moved at high speed while in contact with the rollers without generating abnormal noise or increasing jitter. An object of the present invention is to provide a tape drawing device.

Structure of the Invention The magnetic tape drawer of the present invention connects a magnetic tape to a head from a cassette containing the magnetic tape.

A device for pulling out the magnetic tape in such a manner that the magnetic tape is pulled out, the front roller for pulling out the magnetic tape is located at the tape drawer opening of the cassette and has a roller that is in a non-contact state with the magnetic tape, and the roller has an outer peripheral portion at both ends. are held by oil-impregnated first and second bearing members, the bearing members having an outer circumferential portion larger than the outer circumferential diameter at which the roller contacts the magnetic tape. The first and second bearing member holding members are each held by a holding member, and the first and second bearing member holding members are connected and held by a central shaft that connects and holds the bearing member holding member in a non-contact manner with the inner periphery of the roller, and the first and second bearing member holding members are and the second bearing member holding member is configured to be attached to the holder, so that the magnetic tape can be brought into contact with the roller and wound around the head without generating abnormal noise or increasing jitter. , it is possible to run magnetic tape at high speed.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 4 shows a sectional view of a magnetic tape pull-out device according to embodiments of the present invention. In Figure 4, 31 and 3
6 is a bearing member holding member, 32 and 35 are bearing members made of oil-impregnated metal made by powder metallurgy, 33 is a cylindrical roller, 34 is a hollow shaft that holds and rotates the roller 33, and 37 is a bearing. This is a central axis that connects and holds the member holding members 31 and 36. Note that a male thread 36a is cut in a part of one of the bearing member holding members 36 so as to be coaxial with the central shaft 37.

The operation of the magnetic tape drawer of this embodiment constructed as described above will be described below. First, before pulling out the magnetic tape, it is placed in the tape drawer opening of the cassette containing the magnetic tape, and the magnetic tape and the roller 33
is in a non-contact state.

Next, a male screw 361 provided on the bearing member holding member 36
The holder 3o connected by L moves, so that the roller 33 comes into contact with the tape, pulls out the tape from the cassette, brings it into contact with the cassette, and records or reproduces a signal. At this time, as the tape runs, the roller in contact with the tape receives a frictional force, and since the hollow shaft 34 is press-fitted into the roller 33, the two are integral, and the center that does not contact the hollow shaft 34 It rotates on the inner contact surface of an oil-impregnated metal 32.35 which is a bearing member held by a bearing member holding member 31.36 connected and held by a shaft 37.

As described above, according to this embodiment, the inner contact surface of the fixed bearing member is rotated by the hollow shaft 34 that is press-fitted into the roller 33, so that the inner contact surface of the fixed bearing member is rotated by the hollow shaft 34 that is press-fitted into the roller 33. By keeping the contact surface constant at 1, a so-called running-in effect is produced, and the magnetic tape can be rotated at high speed without increasing rotational runout or imparting vibration to the magnetic tape.

Effects of the Invention As is clear from the above explanation, the present invention has a very compact structure, but the roller core runout is small and can withstand high speed rotation, and even when used for a long time, there is no increase in runout or abnormal noise due to rotation. An excellent effect can be obtained in that a highly practical magnetic tape pull-out device that does not cause such problems can be provided. As a result of this effect, the functions of the magnetic recording and reproducing device are such as fast forwarding and rewinding while the tape is being pulled out and wrapped around the rotating head cylinder, whereas conventional fixed posts are capable of playing the tape by increasing tape tension. Although there have been problems such as scratches and the need for a large drive torque in the tape drive system, this method has the advantage that it can be performed without such problems.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a magnetic recording and reproducing device having a conventional magnetic tape pull-out device, Fig. 2 is a partially enlarged perspective view of the guide post in Fig. 1, and Fig. 3 is a portion near the lock post in Fig. 1. 4 is a sectional view of another example of a conventional post unit, and FIG. 5 is a sectional view of a main part of an embodiment of the present invention. 30...Holder, 31...-Bearing member holding member, 32...Oil-impregnated metal, 33...Roller, 34...Hollow shaft, 35...Oil-impregnated metal, 3
6... Bearing member holding member, 37... Central shaft. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3θ Figure 3 Figure 4 Figure 5 = 33':

Claims (1)

[Claims] A device for pulling out a magnetic tape from a cassette storing a magnetic tape so as to come into contact with a head, the device being in a tape drawer opening of the cassette and out of contact with the magnetic tape before pulling out the magnetic tape. The roller has an oil-impregnated first and second oil-impregnated roller at both ends thereof.
The bearing member is held by first and second bearing member holding members each having an outer circumferential portion larger than the outer circumferential diameter at which the roller contacts the magnetic tape, The first and second bearing member holding members are connected and held by a central shaft that connects and holds the bearing member holding member without contacting the inner periphery of the roller, and
A magnetic tape drawer, characterized in that one of the first and second bearing member holding members is attached to a holder.