JPH04153946A - Magnetic tape guide roller - Google Patents

Abstract

PURPOSE: To stabilize tape traveling by constituting an inner diametral surface part of a roller member to be in contact with a metallic shaft out of a wear- resistant resin material and constituting an outer circumferential surface part of the roller member to be in contact with the magnetic tape out of a metal or inorganic material. CONSTITUTION: The inner diametral surface part 14 of the roller member 12 has a small friction coefft. against the rotary shaft 11, and is composed of a wear-resistant resin having a small characteristic change in a wide temp. range, while the outer circumferential surface part 15 is composed of a metal or inorganic material having a small friction coefft. against the magnetic tape 40. Consequently, even when tape feeding is highly speeded up, secured and stabilized tape traveling can be ensured by the guide roller 10, and also even under a high temp. environment, high precision tape traveling can be maintained, and hence no damage is given to the magnetic tape 40.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a recording/playback device employing a magnetic tape recording method, a recording/playback device, and a rotating magnetic head type magnetic tape used in various information recording/playback devices. The present invention relates to a guide roller of a recording device.

(Prior Art) FIG. 2 is a schematic diagram of a tape running mechanism centered around a rotating magnetic head of a rotating magnetic head type magnetic tape recording device.

In the rotating magnetic head type magnetic tape recording device, the magnetic tape guide rollers 20 are located on both sides of the rotating magnetic head 30, and are designed to correctly slide the magnetic tape 40 against the head 30 to reduce loss torque unevenness during rotation. It is designed to. In particular, in order to record and reproduce magnetic signals with the magnetic tape 40 wound around a cylinder, it is necessary to always keep conditions such as the contact between the head and the tape 40, distance, pressure, angle, speed, etc. be. Therefore, inclined pins 51 and 52 (tape guide posts) are provided on both sides of the head 30 to give an inclined direction to the magnetic tape and guide it. In this way, the upper edge of the magnetic tape 40 is aligned while the lower edge of the tape is aligned with the step provided on the head 30 that serves as a reference for vertical positioning of the lead tape, and the upper edge of the tape is moved so that the lower edge does not separate from the lead. It is made to run while being pressed against the head and rubbing against the head 30.

Conventionally, radial ball bearing link type guide rollers and sliding (sleeve) type guide rollers made of synthetic resin are known as guide rollers used in such magnetic tape recording devices.

However, the radial ball type is filled with lubricating oil due to its structure, and cannot provide stable rotational torque because the viscosity of the oil changes depending on the environment, especially changes in temperature. In addition, the construction is complicated, so it is expensive.

On the other hand, a sliding type guide roller made of synthetic resin is a roller member supported by a metal rotating shaft made of synthetic resin such as polyacetal resin, fluororesin, polyethylene resin, silicone resin, or the like. As the tape running speed of magnetic tape recording devices increases, the wear resistance of the inner diameter of these resin roller members has become a problem. That is, the inner surface of the bearing that comes into contact with the metal rotating shaft is likely to wear out, resulting in insufficient durability. Furthermore, in the case of a guide roller made of resin, damage such as wrinkles is likely to be caused to the magnetic tape that slides on the outer peripheral surface of the guide roller. This is because the magnetic tape is guided with an inclination by the tape guide post as described above, so the magnetic tape shifts in the width direction on the outer peripheral surface of the guide roller, causing the tape edge to strongly press against the flange of the guide roller. This may be caused by being pressed or even by the edge of the tape being caught between the flange and the roller member. This phenomenon of damaging the magnetic tape is caused by the large coefficient of friction between the outer peripheral surface of the guide roller and the back surface of the magnetic tape.

(Problems to be Solved by the Invention) The purpose of the present invention is to enable stable tape running without damaging the magnetic tape even in a wide temperature range and under conditions where the tape running speed increases. An object of the present invention is to provide a magnetic tape guide roller.

(Means for Solving the Problems and Their Effects) The above-mentioned object of the present invention is to provide a metal shaft which is disposed on both sides of the rotating head between the tape supply reel stand and the tape take-up reel stand of a magnetic tape recording device. and a roller member located on the outer periphery of the shaft and supported by the shaft, in which the inner diameter surface of the roller member that contacts the metal shaft is made of a wear-resistant resin material, and the magnetic This was achieved by constructing the outer circumferential surface of the roller member that comes into contact with the tape from metal or inorganic material.

In the magnetic tape guide roller, it is preferable that a polyimide resin be used as the wear-resistant resin material constituting the inner circumferential surface of the roller member, and the outer circumferential surface of the roller member be made of a metal material.

As described above, in the guide roller of the present invention, the inner diameter surface portion of the roller member, that is, the portion where characteristics tend to change in a high temperature environment is made of resin. Therefore, stable rotation is guaranteed over a wide temperature range, and highly accurate and stable tape running can be maintained. In addition, by using a particularly wear-resistant resin material for the inner surface of this roller member, the contact surface with the rotating shaft is resistant to wear and has excellent durability even when feeding the tape at high speeds. . On the other hand, the outer peripheral surface of the guide roller member that the magnetic tape comes into contact with is made of metal or an inorganic material. Since the friction between the metal or inorganic material and the magnetic tape is smaller than that of the resin material, wrinkles and the like do not occur on the magnetic tape on the outer surface of the roller member, as is the case with conventional resin guide rollers.

The present invention will be explained in more detail below.

The magnetic tape guide roller of the present invention includes a metal shaft and a roller member located on the outer periphery of the shaft and supported by the shaft, and the inner diameter surface of the roller member is made of a wear-resistant resin material. . In the present invention, the inner diameter surface portion of the roller member refers to a portion that includes a surface that contacts the outer circumferential surface of the metal shaft of the roller member and generates friction while rotating. In the present invention,
The inner diameter surface portion of the roller member is made of a wear-resistant resin material.

As the wear-resistant resin material, materials such as polyacetal resin, polyethylene resin, and polyimide resin are used, which have a small coefficient of friction with the rotating shaft and whose mechanical properties change little at high temperatures. The material of the rotating shaft is appropriately selected depending on the material of the inner diameter surface portion, and for example, stainless steel material can be used. The inner diameter side surface of the inner diameter surface portion of the roller member can be subjected to surface treatment such as fluororesin coating in order to further reduce friction with the shaft and prevent wear. In the present invention, since the inner diameter surface of the roller member is made of resin, the resin surface formed by cutting by machining or the like is plated or coated with a metal or inorganic material, and the outer circumferential surface of the guide roller is coated. The required smooth surface can be easily formed.

Preferably, the inner diameter surface portion of the roller member of the present invention is made of polyimide resin. Polyimide resin has a wide temperature range (
This is because it has a stable coefficient of friction at a temperature of -20°C to 80°C, for example, and hardly wears even when sliding at high speeds on the inner diameter. In addition, polyimide resin materials exhibit good compatibility with metal plating and thermal spraying applied to their outer peripheral surfaces, and also make it possible to apply ceramic coatings and suba-shittering that require high-temperature thermal spraying. But it's preferable.

The outer peripheral surface portion of the roller member of the present invention is made of metal or inorganic material. Here, the outer circumferential surface portion refers to a portion including the outer circumferential surface of the roller member that comes into contact with the magnetic tape. The metal or inorganic material constituting the outer peripheral surface portion is preferably a material that has low friction with the magnetic tape.

Preferred metals include nickel, chromium, stainless steel, and the like. More preferably, 2·ν Kel is used. Furthermore, examples of the inorganic material constituting the outer circumferential surface portion include titanium nitride and the like. The material of the outer circumferential surface part depends on the type of magnetic tape used, for example, a magnetic tape made of a polyester resin film, or a tape whose back surface is coated with a magnetic material. Choose to be small. It is important that the outer surface of the outer circumferential surface portion, that is, the outer circumferential surface of the roller member, be a smooth surface in order to further reduce friction with the magnetic tape.

The guide roller of the present invention includes, for example, plating the above metal or inorganic material on the outer peripheral surface of the inner diameter surface of the guide roller.
It can be manufactured by forming the outer circumferential surface by attaching it by a method such as thermal spraying or vapor deposition. Further, the guide roller of the present invention has a sleeve formed of metal or inorganic material,
It is also possible to manufacture the sleeve by press-fitting and adhering a resin inner diameter surface portion to the sleeve. In the guide roller of the present invention, one or more intermediate portions may be provided between the inner diameter surface portion and the outer peripheral surface portion.

(Example) An example of the present invention will be described below with reference to the drawings. 1st
The figure is a sectional view of a tape magnetic guide roller 10 according to the present invention. The guide roller 10 includes a central shaft 11 made of metal such as stainless steel, and a guide roller member 12 located on the outer periphery of the shaft 11 and supported by the shaft. The guide roller member 12 includes a main body 14 (inner diameter surface portion) provided with a bearing hollow portion 13 having an inner diameter at a predetermined ratio to the diameter of the central shaft 11 . The main body 14 is molded from a resin selected from the group of polyacetal resin, polyethylene resin, and polyimide resin. The outer surface of the main body 14 is coated with a metal such as nickel, chromium, or stainless steel to a uniform predetermined thickness by plating, thermal spraying, vapor deposition, press-fitting or adhering to a sleeve of these metals, and a coating layer 15 is formed. (outer peripheral surface portion) is formed.

The guide roller member 12 on which the coating layer 15 of metal or inorganic material has been formed is inserted into the rotating shaft 11 made of metal so as to slide and rotate, and the upper and lower ends are connected to the rotating shaft 11 by flanges 16 made of stainless steel or the like. By holding it in a predetermined position, a guide roller 10 is configured.

As shown in FIG. 1, it is preferable that the length of the surface portion of the roller member 12 on which the coating layer 15 is provided is smaller than the length of the portion near the rotating shaft 11 in the longitudinal direction. When this shape is adopted, the friction area between the roller member 12 and the flange 16 is suppressed as much as possible, and the position of the roller member 12 with respect to the rotating shaft 11 is maintained by contacting the flange 16 near the center of the circular end face. The thus configured magnetic tape guide roller 10 can be fixed! As shown in FIG. 2, they are placed on both sides of a rotary head 30 of a magnetic tape recording device. The magnetic tape 40 is fed from a tape supply reel stand (not shown), slides on the outer peripheral surface of the guide roller 10 on the entrance side, and passes through the inclined pin 5 on the entrance side.
1 and sent to the rotating head 3Ω.

After passing through the surface of the rotating head 30, the tape is returned to the original parallel state by the outlet side inclined pin 52, and the outer peripheral surface of the guide roller IO on the outlet side is slid onto the tape take-up reel stand (not shown). Sent.

In a magnetic tape recording device equipped with the magnetic tape guide roller of the present invention having a metal outer circumferential surface and a resin inner circumferential surface as described above, the coefficient of friction between the back surface of the magnetic tape and the outer circumferential surface of the tape guide roller, and the rotation axis and The coefficient of friction between the guide roller and the inner peripheral surface was measured. The measurement was performed at a tape running speed of 0.
The test was carried out under the conditions of 1 mm/see and tape tension of 30 g. The rotating shaft was made of stainless steel. Furthermore, in a similar magnetic tape recording apparatus, the coefficient of friction was also measured when a conventional guide roller was used in place of the guide roller of the present invention.

As a result, the coefficient of friction between the back surface of the magnetic tape and the surface of guide rollers made of various materials is 0.2 to 0.3 for guide rollers made of metal materials such as nickel, chromium, and stainless steel; In the case of a sliding type guide roller made of polyethylene resin or polyimide resin Besubel 5P-211 (polyimide resin graphite 15%, 10% tetratetrafluoroethylene, manufactured by DUNE), 0.
It was 6-0.7.

In addition, the coefficient of friction of guide rollers made of various materials with respect to the rotating shaft of stainless steel is
0,1 for polyethylene resin, polyimide resin)
~0.2, and in the case of metal materials (nickel, chromium, stainless steel), it was 0.6.

As can be seen from these friction coefficients, conventional resin sliding type guide rollers have small opening friction with the rotating shaft, but large friction with the magnetic tape. On the other hand, the guide roller according to the present invention in which the inner diameter surface portion is made of resin and the outer circumferential surface portion is made of metal has low friction with the shaft and also low friction with the magnetic tape.

Table 1 shows a guide roller, which is an embodiment of the present invention, in which the inner diameter surface of the roller member is molded with Besuvel (polyimide resin manufactured by DuPont), and the outer peripheral surface is coated with nickel with a uniform thickness. Characteristics of various conventional guide rollers are evaluated in terms of rotation loss with the rotating shaft on the inner diameter surface (inner diameter rotation loss), stability of tape running on the outer circumferential surface of the roller (tape stability), and stability in a wide temperature range. We have summarized the results of comparing the stability of characteristics (wide temperature range stability), durability, noise, weight, and cost. Each symbol in Table 1 has the following meaning.

■...Excellent. O...I'm satisfied.

Δ...Needs improvement. ×...There is a problem.

Table 1 Inner diameter rotation loss Tape stability Wide temperature range stability Durability Noise li amount Cost Vespel S As can be seen from Table 1, the magnetic tape guide roller according to the present invention has a higher magnetic It satisfies all requirements for guide rollers used in head-type magnetic tape recording devices.

(Effects) As described above, in the magnetic tape guide roller of the present invention, the inner diameter surface of the roller member is made of a wear-resistant resin that has a small coefficient of friction with the rotating shaft and whose characteristics change little over a wide temperature range. The outer peripheral surface portion is made of metal or inorganic material that has a small coefficient of friction with the magnetic tape. As a result, the guide roller of the present invention guarantees reliable and stable tape running even when the tape feeding speed increases, and can maintain highly accurate tape running even in high-temperature environments.
For these reasons, no damage is caused to the magnetic tape.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a magnetic tape guide roller according to an embodiment of the present invention, and FIG. 2 is a perspective view of a magnetic tape recording apparatus equipped with the magnetic tape guide roller of FIG. 1. 10... Magnetic tape guide roller, 11... Shaft, 1
2... Guide roller member, 14... Inner diameter surface portion, 15
. . . Outer peripheral surface portion, 30 . . . Rotating head, 40 . . . Magnetic tape. Applicant's agent Patent attorney Takehiko Suzue

Claims (2)

[Claims] (1) A roller member located between the tape supply reel stand and the tape take-up reel stand of a magnetic tape recording device and placed on both sides of the rotating head, and comprising a metal shaft and a roller member located on the outer periphery of the shaft and supported by the shaft. In the magnetic tape guide roller, the inner surface of the roller member that contacts the metal shaft is made of a wear-resistant resin material, and the outer surface of the roller member that contacts the magnetic tape is made of metal or inorganic material. A magnetic tape guide roller characterized by the following configuration. (2) The magnetic tape guide roller according to claim 1, wherein the wear-resistant resin material constituting the inner circumferential surface of the roller member is a polyimide resin, and the outer circumferential surface of the roller member is made of a metal material.