JPH04259946A - Guide roller - Google Patents

Abstract

PURPOSE:To prevent worn particles from being generated due to wearing between the members of an upper flange and a sleeve and to prevent the worn particles or dust such as cut particles or the like from falling down to a roller main body side and entering a space between the sliding faces of the roller main body and the sleeve. CONSTITUTION:The position of a roller main body (12) on a supporting axis (2) can be adjusted according to the movement of a sleeve (10) caused by the screwing of an upper flange (26) and by fixing an annular body (resin cap 28) composed of synthetic resin to the upper flange (26) and interposing this annular body between the upper flange and the sleeve, direct friction between the upper flange and the sleeve is avoided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to guide rollers used for transporting magnetic tapes in magnetic recording devices and playback devices such as video tape recorders, video cameras, and DATs.

0002

2. Description of the Related Art Conventionally, in video tape recorders, video cameras, DATs, etc., pivot type guide rollers have been used to transport magnetic tapes. This guide roller, for example, elastically supports a lower flange and a metal sleeve on a support shaft via a coiled spring, and then attaches the roller body to the outside of the sleeve, and then attaches it to the top of the support shaft. It has a structure in which a nut-shaped upper flange is attached to the threaded part on the side. In this type of guide roller, by screwing in the upper flange, the span between the upper and lower flanges is set, and the sleeve on the support shaft moves in accordance with the rotation of the upper flange, allowing the position of the roller body to be set as desired. It can be adjusted and set.

0003

By the way, in this guide roller, since the upper flange and the sleeve, which are both made of metal, are in contact with each other, it is difficult to rotate the upper flange when assembling the guide roller or adjusting the position of the roller body. , Chips formed and remaining on the threaded part of the support shaft during cutting move from the threaded part, and abrasion powder is generated due to friction between the upper flange and the sleeve, and the chips and abrasion powder are If it gets between the sliding surfaces of the sleeve and the roller body or adheres to the circumferential surface of the roller body, it will cause problems such as degrading the performance of the guide roller. If dust such as chips or abrasion powder gets into the space between the sliding surface of the sleeve and the roller body, it will cause uneven rotation of the roller body, jitter defects, and roller squeal. If it adheres to the circumferential surface, it will be necessary to remove it, and if it is left unattended, there is a risk that the running of the magnetic tape to be guided may be hindered.

Therefore, the present invention prevents the generation of abrasion powder due to abrasion between the members of the upper flange and the sleeve, and also prevents the abrasion powder and dust such as chips from falling to the roller body side and causing the roller body and sleeve to disintegrate. The purpose is to realize a guide roller that prevents the guide roller from entering between the sliding surfaces of the roller.

[0005]

[Means for Solving the Problems] That is, the guide roller of the present invention has a sleeve (2) formed of metal on the support shaft (2).
10) and a lower flange (16) are elastically supported by a spring (14), and a roller body (12) is rotatably placed on the outside of the sleeve and formed at the end of the support shaft. An upper flange (26) formed of metal is attached to the threaded portion (34), and the position of the roller main body on the support shaft can be adjusted by movement of the sleeve in response to screwing of the upper flange. The present invention is characterized in that an annular body (resin cap 28) made of synthetic resin is fixed to the lower surface of the upper flange, and the annular body is interposed between the upper flange and the sleeve.

[0006]

In the guide roller of the present invention, the annular body fixed to the lower surface of the upper flange is interposed between the upper flange and the sleeve, so that the upper flange and the sleeve are separated by this annular body. Therefore, the upper flange and the sleeve do not come into direct contact with each other, and even when the upper flange is screwed in, it is possible to prevent the generation of abrasion powder due to wear, and to prevent the chips on the threaded part side from falling to the roller body side. This prevents dust from entering the sliding surface between the roller body and the sleeve, thereby avoiding the influence of dust.

[0007]

Embodiment FIGS. 1A and 1B and FIG. 2 show an embodiment of the guide roller of the present invention. This guide roller is provided with a support shaft 2 having a cylindrical shape at the center of rotation, and this support shaft 2 has a stepped part 4 in the middle, a large diameter part 6 on the lower side, and a small diameter part on the upper side. A portion 8 is formed. On the side of the small diameter portion 8, there is provided a sleeve 10 made of metal as well as an elastic support means that elastically supports the roller body 12 made of synthetic resin or non-magnetized metal, and the outer diameter is approximately the same as that of the large diameter portion 8. A coil-shaped spring 14 whose diameter and inner diameter are larger than that of the small diameter portion 8 is fitted into the spring 14.
A sleeve 10 is attached to the upper side of the sleeve 10 via a lower flange 16 formed of metal.

The lower flange 16 has a cylindrical protrusion 18 into which the spring 14 is inserted and supports the sleeve 10, and has an annular flange portion 20 formed at its lower end. A through hole 22 slightly larger than the small diameter portion 8 of the support shaft 2 is formed in the center of the cylindrical protrusion 18 .

The sleeve 10 is a flat cylindrical body made of metal such as brass or stainless steel, and serves as a substantial bearing for the cylindrical roller body 12 to be installed on the outer peripheral surface of the sleeve 10. It is. A roller body 12 is rotatably attached to the outer peripheral surface of the sleeve 10.

The roller body 12 is formed into a cylindrical shape of synthetic resin or metal that does not cause magnetic influence in order to avoid magnetic influence on the magnetic tape to be guided. A large-diameter portion 24 is formed, and a cylindrical protrusion 18 is inserted into the large-diameter portion 24 to prevent contact between the roller body 12 and the lower flange 16.

A nut-shaped upper flange 26 is attached to the threaded portion 34 formed at the top of the support shaft 2, and a resin annular body formed of synthetic resin is attached to the lower surface side of the upper flange 26. A cap 28 is formed integrally with the upper flange 26, and an adjustment groove 30 for inserting an adjustment driver is formed in the upper surface of the cap 28.

As shown in FIG. 1B, the resin cap 28 is formed to be slightly smaller than the inner diameter of the recess 32 formed in the roller body 12 in order to avoid contact with the roller body 12. The lower surface of the upper flange 26 is formed, for example, by insert molding of synthetic resin, and a through hole 36 through which the support shaft 2 passes is formed in the center thereof. Further, a large-diameter portion 38 for enclosing the sleeve 10 is formed on the lower surface side of the resin cap 28, and the upper end portion of the sleeve 10 is inserted into the large-diameter portion 38. Therefore, the resin cap 28 fixed to the upper flange 26 is sandwiched between the upper flange 26 and the sleeve 10 without contacting the roller main body 12.

According to this configuration, as shown in FIG. 2, the spring 14 is attached to the support shaft 2, and then the lower flange 16 and the sleeve 10 are fitted, and then the sleeve 1
0, and the upper flange 26 is attached to the threaded portion 34 of the support shaft 2. By rotating the upper flange 26 and moving the sleeve 10 against the spring 14, the roller body 12 can be adjusted and set at a desired position.

When the upper flange 26 is rotated when assembling the guide roller and setting the position of the roller main body 12, the upper flange 26 is integrated with the flange-shaped resin cap 28 fixed to the lower surface of the upper flange 26. Since the upper flange 26 and the sleeve 10 rotate, there is no direct contact between the upper flange 26 and the sleeve 10. Therefore, the two do not come into contact and wear out, and generation of abrasion powder as in the conventional case can be reliably prevented.

Furthermore, the upper flange 26 and the resin cap 28
Even if there is friction, the resin cap 28 is sticky, so it does not generate powder dust due to wear, and the influence of metal powder and dust can be reliably avoided, increasing the reliability of the guide roller. It is possible to reliably prevent the occurrence of uneven rotation as in the conventional case. Further, since the resin cap 28 is formed to have a larger diameter than the sleeve 10, the gap between the sleeve 10 and the roller body 12 is covered with the resin cap 28, and the threaded portion 3
It is possible to prevent the chips generated during the cutting process in step 4 from falling to the end surface side of the roller body 12.

[0016]

As explained above, according to the present invention, the annular body made of synthetic resin is fixed to the upper flange and interposed between the upper flange and the sleeve, so that the upper flange and the sleeve can be separated. It is possible to avoid direct metal-to-metal contact between the parts, reliably prevent the generation of abrasion powder due to the rotation of the upper flange, and also prevent dust such as chips generated during cutting of the threaded part from being transferred to the roller body side. This prevents dust from falling or entering between the sliding surface between the roller body and the sleeve, and ensures that dust does not cause uneven rotation of the roller body, jitter defects, roller squeal, or influence on the magnetic tape, etc. that should be guided. This can be prevented and driving performance can be improved. Further, since the annular body made of synthetic resin is integrated with the upper flange, the number of assembly steps does not increase due to an increase in the number of parts, and a highly reliable guide roller can be realized.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the guide roller of the present invention;
A) is a longitudinal cross-sectional view of the guide roller, and (B) is a partial cross-sectional view of the guide roller.

FIG. 2 is a partially exploded sectional view of the upper flange side of the guide roller shown in FIG. 1;

[Explanation of symbols]

2...Support shaft 10...Sleeve 12...Roller body 14...Spring 16...Lower flange 26...Top flange 28...Resin cap (annular body) 34...Threaded part

Claims (1)

[Claims] Claim 1: A sleeve and a lower flange formed of metal are elastically supported on a support shaft by a spring, and a roller body is rotatably placed on the outside of the sleeve, and the roller body is rotatably mounted on an end of the support shaft. An upper flange made of metal is attached to the formed threaded portion, and the position of the roller main body on the support shaft can be adjusted by movement of the sleeve in response to screwing of the upper flange,
A guide roller characterized in that an annular body made of synthetic resin is fixed to the lower surface of the upper flange, and the annular body is interposed between the upper flange and the sleeve.