JP2687294B2 - Guide roller - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide roller suitable for controlling the position of a magnetic tape that is transferred by being attached thereto in a video tape recorder or the like.

[Conventional technology]

A conventional example of this type of guide roller will be described with reference to the partial sectional view of FIG.

In FIG. 2, reference numeral 1 denotes a shaft, which is coaxially fitted with a guide roller rotating mechanism 2 and a ring 4 having a male screw 3 formed on the outer periphery thereof. Installed after Reference numeral 5 is a cylindrical rotating roller that serves the tape guide surface of the guide roller, and is formed of resin. When assembling the rotation mechanism 2 of the guide roller, the flange 7 having the slit 6 is inserted into one end of the shaft 1 and fixed, and the flange 7 side faces down. Then, the rotary roller 5 is inserted into the shaft 1 to be loosely fitted thereto, and the hollow flange 8 is press-fitted thereon, and the rotary roller 5 is fixed at a position where the rotation is smooth to form the guide roller rotary mechanism 2. After that, using the jig,
Press-fit. Although not shown, the guide roller is used by being erected at a predetermined angle on a metal base of a video tape recorder, for example. In this case, the metal base is provided with a female screw hole to be screwed into the male screw 3 provided on the ring 4, and a slotted screwdriver provided on the flange 7 is used to insert a flat-blade screwdriver into the entire guide roller. The height of the guide roller with respect to the metal base is adjusted by rotating and tightening the male screw 3 provided on the thumbwheel 4.

[Problems to be solved by the invention]

When the magnetic tape is attached to the tape guide surface of the guide roller and transferred, the rotary roller rotates at a substantially constant speed. This constant velocity motion of the rotating roller has a function of absorbing the vibration generated in the magnetic tape being transferred, and is more effective as the inertia moment of the rotating roller is larger.

In the conventional guide roller, since the rotating roller is formed only of resin, there is a problem that the diameter becomes thicker when the inertia moment of the rotating roller is increased and the guide roller becomes larger.

[Means for solving the problem]

According to the present invention, both end surfaces and an inner surface of a metal cylinder to which a tape is attached and transferred to a peripheral surface are formed of resin, and a brim-shaped end portion having a diameter smaller than an outer diameter of the metal cylinder is provided at both ends of the metal cylinder. A rotating roller having an inner cylinder formed on a surface thereof and formed coaxially with the metal cylinder is inserted into a single shaft by sandwiching it between hollow first and second flanges, and is brought into contact with both the flanges and the shaft. The resin forming the inner cylinder is interposed on the contact surface of the rotating roller so that the metal cylinder does not contact the flanges and the shaft, and the tape does not contact the resin forming the inner cylinder. It is characterized in that it is configured in.

[Action]

In the guide roller of the present invention, since the rotating roller in which both end surfaces and the inner surface of the metal cylinder are formed of resin is adopted, the rotating roller having a diameter sufficiently smaller than that in the case of using the rotating roller of only resin. The vibration of the magnetic tape that is transferred while being attached to the tape guide surface is sufficiently absorbed. Further, a resin forming an inner cylinder is interposed on a surface of the rotating roller that contacts the flange and the shaft, and a gap is formed between the metal cylinder and the both flanges. Since the rotating roller rotates smoothly without making contact with the shaft, the advantage of the conventional one formed only of resin is not impaired. Moreover, the magnetic tape running while contacting the outer peripheral surface of the metal cylinder does not contact the resin forming the inner cylinder. Therefore, if the outer periphery of the single-material metal cylinder forming the contact surface of the magnetic tape is precisely processed, the vibration of the magnetic tape transferred along with the outer peripheral surface of the metal cylinder is sufficiently absorbed.

[Embodiment] FIG. 1 is a partial sectional view showing an embodiment of the present invention. The present invention will be described below with reference to the embodiment shown in FIG. In FIG. 1, the same reference numerals as those in FIG. 2 indicate the same parts.

Reference numeral 1 denotes a shaft, which is coaxially fitted with a rotation mechanism of the guide roller and a ring member 4 having a male screw 3 formed on the outer periphery thereof as described in FIG. It is installed after the mechanism is assembled. Reference numeral 10 denotes a rotating roller, which is composed of a metal cylinder 11 which is in charge of the tape guide surface of the guide roller, and the inner cylinder of which is a resin 14 having self-lubricating property.
(In the embodiment, the central portion and the inner surface of both end surfaces of the metal cylinder 11 are covered with a polyacetal resin.) The end surface of this inner cylinder is the outer diameter of the metal cylinder 11 at both ends of the metal cylinder 11. The diameter of the metal cylinder 11 is smaller than that of the metal cylinder 11. This metal tube 11
The ends of the inner cylinder, which are coaxial with the metal cylinder 11, have flange-shaped ends 12 and 13 having a diameter smaller than the outer diameter of the metal cylinder 11 at both ends of the inner cylinder. As for the assembly of the guide roller rotation mechanism, the flange 7 having the slits 6 is inserted into one end of the shaft 1 and fixed, and the flange 7 side faces down, as in the case described with reference to FIG. Then, the rotary roller 10 is inserted through the shaft 1 and loosely fitted, and the hollow flange 8 is press-fit onto the rotary roller 10 to
The rotation of 10 is fixed at a smooth position to form a guide roller rotation mechanism. In this guide roller rotating mechanism, the flange-shaped end portions 1 on both ends of the resin 14 forming the inner cylinder of the rotating roller are used.
2 and 13 come into contact with the flanges 7 and 8 fixed to the shaft 1, and a gap is formed between both ends of the metal cylinder 11 and the flanges 7 and 8 fixed to the shaft 11. ,
It is configured so as not to contact the flanges 7 and 8. In this case as well, a jig is used in the same manner as described with reference to FIG.
Are pressed into the shaft 1. In the same way as described with reference to FIG. 2, insert a flat-blade screwdriver into the slot 6 to rotate the entire guide roller, and tighten the male screw 3 provided on the thumbwheel 4 to tighten the height of the guide roller relative to the metal base. Is adjusted.

〔The invention's effect〕

As explained above, in the guide roller of the present invention,
Since a metal cylinder having a specific gravity sufficiently larger than that of resin is used and a rotating roller in which both end surfaces and an inner surface of the metal cylinder are formed of resin is adopted, compared to a case where a rotating roller formed of only resin is adopted. Even though the rotating roller has a sufficiently small diameter, the moment of inertia can be increased, and the vibration of the magnetic tape transferred while being in contact with the tape guide surface is sufficiently absorbed. Further, a resin forming an inner cylinder is interposed on a surface of the rotating roller that contacts the flange and the shaft, and a gap is formed between the metal cylinder and the both flanges. Since the rotating roller rotates smoothly without making contact with the shaft, the advantage of the conventional one formed only of resin is not impaired. Moreover, the magnetic tape running while contacting the outer peripheral surface of the metal cylinder does not contact the resin forming the inner cylinder. Therefore, the magnetic tape is transferred only in contact with the outer peripheral surface of the metal cylinder, but is not in contact with the resin, so that it is not affected by the difference in thermal expansion between the metal and the resin due to the temperature change. Furthermore, since the tape guide surface (contact surface) of the magnetic tape is formed on the outer circumference of a single piece of metal cylinder, the tape guide surface (contact surface) of the magnetic tape can be properly adjusted by precisely processing the outer peripheral surface of the metal cylinder. It has an excellent effect such as being able to be formed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional view of a guide roller showing an embodiment of the present invention, and FIG. 2 is a partial sectional view showing a conventional example. 1 …… Shaft 7,8 …… Flange 10 …… Rotating roller 11 …… Metal cylinder 14 …… Resin

Claims (1)

(57) [Claims] 1. A metal cylinder, to which a tape is attached while being attached to a peripheral surface thereof, is formed of resin on both end surfaces and an inner surface, and a flange-shaped end portion having a diameter smaller than an outer diameter of the metal cylinder is formed on the metal cylinder. A rotary roller having inner cylinders formed on both end surfaces coaxial with the metal cylinder is sandwiched between hollow first and second flanges and sequentially inserted into a single shaft to contact both flanges and the shaft. A resin forming the inner cylinder is interposed on the contact surface of the rotating roller, the metal cylinder does not contact the flanges and the shaft, and the tape does not contact the resin forming the inner cylinder. A guide roller having the above structure.