JPH05337815A - Method of ultra-finishing thin wall ring and device therefore, and thin wall ring used in the method - Google Patents

Abstract

PURPOSE:To simply and precisely polish the outer peripheral surface of a ring having a slit. CONSTITUTION:A split ring 11 is rotated while axially conveyed. Meanwhile, a grind wheel 7 which is arranged being inclined so as to cross slits 11a is oscillated in a direction in which the ring 11 is conveyed, and is made into press-contact with the outer peripheral surface of the ring. Accordingly, the polishing surface of the grind wheel 7 is successively made into contact with the slits 11a of the ring 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of superfinishing a thin-walled half ring, an apparatus therefor, and a thin-walled half ring used in the method.

[0002]

2. Description of the Related Art In recent years, for example, as a ring used for a magnetic tape guide roller of a video cassette, a thin plate-like body is formed into a cylindrical shape in order to reduce costs.
So-called half rings have been used. Since the magnetic tape of this ring is in direct sliding contact with the outer peripheral surface, it is necessary to reduce the surface roughness and finish the roundness with high accuracy. Conventionally, this type of ring has been superfinished as shown in FIG.
As shown in FIG.
It is carried out while being rotated by 21 while being conveyed in the axial direction, and a grindstone 22 slightly vibrated in this conveying direction is pressed against the ring 20 from above.

The ring 20 has a slit 20a in the axial direction, and the slit 20a is parallel to the longitudinal direction of the grindstone 22. Therefore, the grindstone 22
However, when the ring 20 is located at the edge portion 20b that is weakest against bending stress due to the rotation, the load concentrates on the edge portion 20b and the ring is deformed. As a result, the circularity of the ring becomes poor. Further, as the roundness deteriorates, it becomes difficult to convey the ring 20 by the hourglass-shaped rollers 21 and 21, and in some cases, the step generated in the slit 20a may damage the grindstone, which makes continuous processing impossible. .. Therefore, conventionally, superfinishing has been performed with the core rod passed through the ring 20.

[0004]

However, in the method of using such a core rod, the number of parts is increased, the attaching / detaching process is required, and the inner diameter of the ring is required to have high precision. , Various problems occurred. In view of the above problems, the present invention provides a method of superfinishing a thin half-divided ring capable of polishing the outer peripheral surface easily and with high accuracy, an apparatus thereof, and a thin-walled half-divided ring used in the processing method. To aim.

[0005]

In order to achieve the above object, a superfinishing method according to the present invention comprises forming a slit between opposing edges by bending a thin plate member into a cylindrical shape. A superfinishing method for a thin-walled half-divided ring in which the ring is conveyed in the axial direction while rotating in the circumferential direction, and a substantially rectangular parallelepiped grindstone is pressed against the outer peripheral surface of the ring while vibrating in the ring conveying direction. At
The grindstone is obliquely arranged so as to intersect with the slit of the ring, and its polishing surface has a shape along the outer peripheral surface of the half ring.

Further, the superfinishing apparatus according to the present invention rotates a ring formed by bending a thin plate member into a cylindrical shape so as to form slits between opposed edges in the circumferential direction. While in the super-finishing apparatus comprising a transporting means for transporting in the axial direction and a polishing means for press-contacting the outer peripheral surface of the ring while vibrating a substantially rectangular parallelepiped grindstone in the transport direction of the ring, the grindstone of the ring The polishing surface is inclined so as to intersect with the slit, and the polishing surface is formed along the outer peripheral surface of the ring. Further, the half ring according to the present invention is one in which the slit of the thin plate member is inclined with respect to the axial direction.

[0007]

In the above superfinishing method or apparatus, since the grindstone slidably contacts the slit of the ring, the load of the grindstone is dispersed without concentrating on the edge portion forming the slit. As a result, the ring is processed with high roundness and high accuracy without deformation. Further, in the thin-walled half ring used in the superfinishing method, even if the grindstones are arranged along the transport direction, the load by the grindstones is not concentrated and dispersed at the edge portion, so that it does not deform. It is processed with high precision.

[0008]

Embodiments of the present invention will now be described with reference to FIGS. Fig. 1 shows a super finishing machine,
Reference numeral 1 is a vibrating body. Rough, medium, and finishing ones are sequentially arranged at three locations in the conveying direction of the ring 11 described below.
These vibrate slightly at high speed in the carrying direction. Reference numeral 2 is a pressurizing cylinder, which is fixed to each of the vibrating bodies 1 and has a shaft portion 3 by hydraulic pressure or the like.
Move up and down. A mounting base 4 is fixed to the tip of the shaft portion 3 so that its longitudinal direction is along the vibration direction of the vibrating body 1. The upper surface of the mounting base 4 is formed in a stepped shape, a through hole 5 is formed in the central portion of the lower stage, and arcuate screwing holes 6 and 6 centered on the through hole 5 are formed at both ends. ..

Reference numeral 7 denotes a grindstone, which has a substantially rectangular parallelepiped shape and whose grain size is successively finer in the carrying direction. The upper end of the grindstone 7 is fixed to a groove 9 formed on the lower end surface of the holder 8. A protrusion 10 is rotatably fitted in the through hole 5 of the mount 4 at the center of the upper end surface of the holder 8. Further, screw holes (not shown) are formed at both ends of the holder 8 so as to correspond to the screw holes 6 and 6.

The holder 8 has the protrusion 10 on the mount 4.
It is attached by fitting it into the through hole 5 of FIG. 1, tilting it at an arbitrary angle with respect to the slit 11a of the ring 11, and screwing the mounting bolt 6a through the screw holes 6 and 6. As shown in FIG. 3, the polishing surface of the grindstone 7 is formed as a three-dimensional curved surface so as to be uniformly pressed against the outer peripheral surface of the ring 11 described below when it is lowered as it is in an inclined state. The ring 11 is formed by bending a thin plate-shaped body into a cylindrical shape, and has opposing edges 11b and 11b.
Slit 11 formed by (indicated by diagonal lines in the figure)
a is parallel to the axial direction.

In the superfinishing apparatus having the above-described structure, the ring 11 is rotated by the conventionally known drum-shaped rollers 12 and 12 and conveyed in the arrow direction. Then, the vibrating body 1 vibrates the grindstone 7 in the conveying direction of the ring 11 to drive the pressure cylinder 2 to lower the grindstone 7, and the polishing surface thereof is brought into pressure contact with the outer peripheral surface of the ring 11. In this state, the grindstone 7 obliquely abuts the slit 11a of the ring 11 as indicated by the chain double-dashed line in FIG. Therefore,
As shown in FIG. 3, the grindstone 7 is brought into sliding contact with the both end edge portions 11b sequentially from one end side by the rotation of the ring 11. As a result, since the load applied from the grindstone 7 to the outer peripheral surface of the ring 11 is dispersed in the circumferential direction, the load is concentratedly applied to the edge portion of the ring having the smallest bending rigidity as in the conventional example shown in FIG. Never. Therefore, ring 1
No. 1 is processed with high roundness and high precision without deformation.

In the above embodiment, the grindstone 7 is attached to the ring 1.
Although the slit 11a and the grindstone 7 are not parallel to each other by inclining with respect to the slit 11a of No. 1, the slit 13a is formed obliquely with respect to the axial direction of the ring 11 as shown in FIG. May be. in this case,
The grindstone 7 can be provided along the transport direction of the ring 11, and existing equipment can be used. Also, grindstone 7
May be attached so as to intersect with the slit 11a of the ring 11 by inclining to the side opposite to the above-mentioned embodiment. However, the grinding surface of the grindstone 7 has a ring 11 depending on the mounting direction.
It is necessary to replace it with one that follows the outer peripheral surface of.

[0013]

As is apparent from the above description, according to the method and apparatus for superfinishing a thin half ring according to claims 1 and 2, the positional relationship between the slit of the ring and the grindstone is always oblique. Since the outer circumferential surface of the ring is polished by intersecting so that the large load of the entire grindstone is not concentrated on one edge near the slit, the load divided into two is applied to both edges. This prevents the ring from being deformed. Therefore, the ring can be continuously machined, and its roundness can be finished with high accuracy without using a core rod as in the conventional case, the working efficiency is improved, and the production cost can be reduced. Further, according to the thin-walled half ring according to claim 3, even if the existing equipment is used,
The outer peripheral surface of the ring can be superfinished without being deformed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a polishing mechanism of a super-finishing device according to this embodiment.

FIG. 2 is a plan view showing a conveyed state of a ring according to the present embodiment.

FIG. 3 is a perspective view showing a polished state of the ring according to the present embodiment.

FIG. 4 is a plan view of a ring according to another embodiment.

FIG. 5 is a side view showing a polished state of a ring according to a conventional example.

[Explanation of symbols]

1 ... Vibrating body, 2 ... Pressure cylinder, 7 ... Grinding stone, 11, 13
... Rings, 11b, 13a ... Edges, 12 ... Hourglass rollers.

Claims (3)

[Claims] 1. A ring formed by bending a thin-walled plate into a cylindrical shape to form slits between opposed edges is conveyed in the axial direction while being rotated in the circumferential direction, and at the same time, the ring. In the superfinishing method of a thin half-divided ring that press-contacts while vibrating a substantially rectangular parallelepiped-shaped grindstone on the outer peripheral surface of the ring, the grindstone is obliquely arranged so as to intersect the ring slit, A method for superfinishing a thin-walled half-ring, characterized in that its polished surface is shaped along the outer peripheral surface of the half-ring. 2. A conveying means for conveying a ring formed by bending a thin plate body into a cylindrical shape to form a slit between opposed edge portions in an axial direction while rotating the ring in a circumferential direction thereof. In a super-finishing apparatus including a polishing means that presses a substantially rectangular grindstone on the outer peripheral surface of the ring while vibrating in the transport direction of the ring, the grindstone is tilted so as to intersect the slit of the ring. At the same time, a superfinishing device for a thin-walled half-ring is characterized in that its polishing surface is shaped along the outer peripheral surface of the ring. 3. The thin-walled half-ring used in the processing method according to claim 1, wherein the slit of the thin-walled plate-like body is inclined with respect to the axial direction.