JPS5829167A - Tape guide - Google Patents

Abstract

PURPOSE:To perform stable tape run without wear of tape contact surface and uneven play, by making a tape guide rotating state or rotating stop state according to the tape run speed. CONSTITUTION:Tape run gives a torque to a guide 21. The relation of rotating friction torque T between a support shaft 12 and the guide 21 due to viscous material of grooves 16 and 18 and number of rotation, is to block the rotation of the guide 21 with larger rotation friction torque T. On the other hand, a dynamic friction force F is decreased together with a tape run speed (f). That is, the dynamic friction force F between the tape and the guide 21 is the rotation providing torque to the guide 21, when the tape run speed (f) is increased, the rotation providing torque to the guide 21 is decreased. Thus, at f<f1, the dynamic friction force F, that is, the rotation providing torque to the guide 21 is made larger than the torque T, then the guide 21 is turned and acts like a rotary type guide.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in tape guides used in tape-using equipment such as video tape recorders.

As is well known, tape-using devices such as tape recorders and videotape recorders that use tape to record and reproduce information signals require improvements in the stability of tape running and improvements in tape running during the tape running path. A single tape guide is used to change the direction of travel.

As the tape guide, fixed types and rotary types are used depending on the magnitude of the wrapping angle of the tape around the tape guide when changing the tape running direction, the tape running speed, etc.

By the way, in the above-mentioned fixed tape guide, the team
Not only will the contact surface be worn away, but especially in the case of magnetic tape, the magnetic powder may be burned onto the contact surface of the tape guide, or the tape may become wrapped around the tape guide due to humidity, static electricity, etc. An undesirable situation occurs.Furthermore, in the above-mentioned rotary type f: If id, the rotation mechanism is & -
Since the tape is constructed using bearings, oil-less metal, etc., it is prone to rattling and eccentricity due to aging, and if it becomes unable to rotate smoothly according to the tape running speed, the tape running This causes negative effects, making it impossible to perform stable recording and playback, and causing inconveniences such as damage and cutting of the tape. In addition, the one-rotation type tag guide has a complicated structure and is difficult to manufacture], and there are also problems such as being economically disadvantageous. This invention was made in consideration of the above circumstances, and In order to achieve a rotating state and a rotating stopped state, it is particularly important to provide an extremely good coefficient f and f which allows the tape to run stably without wobbling during abrasion of the tape contact surface. purpose.

The details of the embodiment of this invention will be described below with reference to the drawings.
IIK explain. In FIG. 1, reference numeral 11 denotes a support shaft, which is composed of a support shaft portion 12 formed in a substantially cylindrical shape and a base @ 18 formed in a substantially brim shape at the lower part of the scissors support shaft 5120 in the drawing. This support shaft 11Fi is provided with a protruding lower end portion of its base portion 130 in FIG. It is installed in the main chassis by being screwed into nine predetermined mounting portions. Additionally, a ring-shaped groove 16 is formed along the circumference of the metal part 1j at the upper end of the table 1BJJ in the drawing.

On the other hand, the support shaft portion 12 of the support shaft 11 has its circumference @W5i
There are 1 predetermined intervals at the top and bottom of the figure of t.
A plurality of grooves @111 (in the illustrated case, three grooves at the top and bottom in the figure) are formed along the 20-circumference.

Furthermore, a nine-wide concave s1# is formed at approximately the center of the circumferential side portion 11 of the support shaft portion 12 along the circumference of the support shaft portion 12. That is, the support shaft portion 12 has a circumferential side portion 17.
It is partially left in the shape of a brim.

An implantable threaded portion 20 is provided in a protruding manner at the center of the upper end of the support shaft portion 12 in the drawing.

Here, a substantially cylindrical guide 21 is fitted onto the support shaft fi511 of the support shaft 11 so as to be rotatable about the axis of the support shaft portion 12. That is, the guide 21 rotates with its inner circumferential portion 22 facing the circumferential side portion 11 of the support shaft @12 at an interval to be described later. Additionally, collar portions 23924 are formed at the upper and lower ends of the guide 21 in the drawing. Among these, Tsuba 1111J (Ha, Dai@11
The groove 1d is closed to dust.

Then, the groove portion 1# formed in the support shaft portion 12 and the stand 8
1 IO#I# Part 1 Place a roughly heast-shaped viscous material (for example, Teflon paste, etc.) on the inside of II. At this time, assuming that the particle diameter of the viscous material is, for example, 2G (μm), the distance between the support shaft portion 120 circumferential portion 11 and the inner peripheral portion z2 of the guide 21 is approximately 1O-15 (μm). It is desirable to do so.

Here, the cap 25f is screwed onto the implanted screw @xe protruding from the support shaft 517. This is from K, girl
l is a fist that is prevented from being pulled out, and one above the cuff.
When the particle size of the viscous material is as described above, the distance between the lower surface of the zs in the figure and the flange 23 of the guide 110 is approximately 1
0 to 20 (μ sea bream) is desirable.

In this way, the distance between the circumference @81F of the support shaft IB J J and the inner peripheral portion 22 of the guide 5-21, and the distance between the cap 25 and the flange portion 23 of the ID 2, are adjusted according to the particles of the viscous material. By determining the angle of the guide 21 in the radial direction and the thrust direction, the guide 21 can be held in place.

In the above configuration, a tape (not shown) is brought into contact with the guide JJK and run. At this time, a rotational force is applied to the guide xirtc in accordance with the tape running. Here, if the rotational speed of the guide 21 is ω, and the rotational friction torque between the support shaft s11 and the f-id 21 due to the viscous material is t−T, then as shown in the second FIA (a) K, the rotational speed ω is Faster lateral, rotational friction torque T is large, Tsuku guide 21
This will prevent zero rotation.

On the other hand, if the running speed of the tape is f and the kinetic frictional force between the tape and the guide 21 is 1 kF, then the kinetic frictional force F decreases as the tape running speed f increases as shown at 5 in FIG. 2(b)K. In other words, since the dynamic frictional force F between the tape and the guide 21 is the torque that imparts rotation to the guide 21, as the tape running speed 6-f increases, the torque that imparts rotation to the guides x and t decreases. It is.

Therefore, as shown in Fig. 2(, ), when the running speed f per tape is low (f in the figure is a speed of less than 10 seconds), the kinetic friction force F between the tape and the guide xi is The rotation imparting torque to the guide 1 and the rotation of the support shaft 12 is
! When the torque T is sufficiently large, the guide 21 rotates and becomes a rotating tape guide. Then, the tape running speed f
As becomes higher, the rotation imparting torque and the rotation original torque T are balanced (speed f1 in the figure). At this time,
Guide 2 stops rotating, and even if the tape running speed f is increased above this speed, guide 1 does not rotate and becomes a fixed tape guide.

Therefore, according to the configuration of the above embodiment, the tape running speed f below f1 in FIG. In the high-speed running range and the tape running range, the guide J can be rotated in the tape running range at low speeds, and the guide 2 is fixed in the tape running high-speed range. It is possible to prevent wear, seizure, wrapping, etc.

In addition, because it uses a paste-like viscous material, it does not suffer from wobbling or eccentricity due to aging, unlike conventional rotary tape guides, and it is believed that it can fully contribute to stable and reliable recording and playback. In addition, damage to the tape hardly occurs. Furthermore, it has a simple structure, is easy to manufacture, and is economically advantageous.

In addition, conventional rotary tape guides produce abnormal images and abnormal sounds, especially when the tape is running at high speeds, but according to the above embodiment, the guide 27 is fixed in the tape running range at high speeds. Therefore, it is possible to prevent the above-mentioned abnormal vibrations, abnormal sounds, etc. from occurring.

Here, although Teflon paste is shown as the viscous material in the above embodiment, it is needless to say that the material is not limited to this, and any material having an appropriate viscosity and particle size can be used depending on the actual usage situation.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without departing from the gist thereof.

Therefore, as described above, according to the present invention, since the rotating state and the rotating stopped state are made according to the tape running speed, there is no abrasion or rattling of the contact surface of the chip, and stable chip running is possible. It is possible to provide an extremely good tape guide that allows the tape guide to be used.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the tape guide according to the present invention, and FIGS. 2(a) to (e) U are characteristic curves ll1I diagrams for explaining the operation of the same embodiment. 11... Support shaft, 12... Support shaft part, 13... Stand part,
14...Protrusion, 15...Threaded hole part, 16...Groove part, 17...Surrounding side part, 18...SS, 19...Recessed part, 2Q...Installed screw part, 21...Guide, 12...
-Inner circumference, 13.24--flange, 25...kia, g. 9- Figure 1

Claims (1)

[Claims] In a tape guide in which a substantially cylindrical guide is rotatably fitted to a support shaft, a groove is formed between the support shaft and the guide, and a viscous material in the form of a strip is sealed in the groove. The tape guide is characterized in that the guide is configured to be in a rotating state and a rotating stopped state depending on the running speed of the tape running in contact with the guy PK.