JP2000094306A - Machining method for cylindrical body-outside diametric surface, and cylindrical body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a machining method for producing high precision rollers in large quantities inexpensively. SOLUTION: A holding member 3 provided with guide grooves 4 radially penetrating the holding member is provided between upper and lower disks 1, 2 having flat opposite surfaces. Cylindrical bodies 5 are supplied to the guide grooves 4, and a load P is applied to the outside diametric surface of each of the cylindrical bodies. The holding member 3 is fixed, and rotation in the opposite direction is given to the upper and lower disks 1, 2 to polish the outside diametric surfaces of the cylindrical bodies 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller for a roller bearing (a cylindrical roller, a rod roller, a needle roller) and a cylindrical body such as a microshaft used for a small precision motor, which has a required outer diameter surface. The present invention relates to a novel processing method capable of forming a high precision and inexpensively.

[0002]

2. Description of the Related Art When manufacturing a cylindrical body as described above, generally, a cut or drawn wire is cut into a predetermined length, heat-treated, and then subjected to centerless polishing on an outer diameter surface. Grinding by machine. If higher accuracy is required, after grinding, super finishing or tumbling is performed, and if necessary, the outer diameter is measured and selected, and accuracy such as surface roughness and dimensional variation of the outer diameter surface is determined. Is secured.

[0003]

However, the performance required of the roller bearings has been improving year by year, and in order to satisfy this demand, it is essential to improve the accuracy of the rollers which greatly affects the performance of the roller bearings. It is a condition. Specifically, there is a strong demand for producing a large number of high-precision rollers having a difference in outer diameter dimension within one lot of 0.001 mm or less and an outer diameter surface roughness of 0.05 μmRz or less at a large amount and at low cost. The present invention has been made in view of the above circumstances, and has as its object to provide a processing method capable of making a large amount of high-precision rollers at a low cost and a cylindrical body subjected to such processing. .

[0004]

In order to achieve the above object, according to the present invention, a holding member having a guide groove penetrating in a radial direction is provided between upper and lower disks having flat opposing surfaces. Along with supplying the cylindrical body to the groove, a load is applied between the upper and lower disks and the outer diameter surface of the cylindrical body, and the holding member is fixed, while the upper and lower disks are rotated in opposite directions. The outer diameter surface of the cylindrical body is machined.

In the present invention, since the cylindrical body rotates in response to the rotation of the upper and lower disks, the outer peripheral surface of the cylindrical body can be ground by this rotational movement. In the present invention,
The material of the upper and lower disks and the holding member may be appropriately selected according to the object to be processed, but in addition to metal, a grindstone, a synthetic resin,
Synthetic rubber or the like is used. In the present invention, since the opposing surfaces of the upper and lower disks are flat, among the plurality of cylinders sandwiched between the upper and lower disks, the one having a larger outer diameter dimension receives a larger load than the smaller one during processing, and The amount of cutting increases,
The external dimensions are automatically made uniform. The surface roughness is closely related to the cutting amount, and the smaller the cutting amount of the cylindrical body to be processed is, the smaller the surface roughness becomes, and a better surface can be obtained.

Further, in the present invention, it is preferable that a difference be provided between the rotational speeds of the upper and lower disks, and that the guide groove be inclined by a predetermined angle with respect to the radius line of the holding member. According to the second aspect of the present invention, slippage occurs between the disk and the cylindrical body to be processed, and the slippage amount increases as the rotation speed difference increases, and as the slippage amount increases, the cutting amount also increases. Therefore, the amount of cutting can be changed by adjusting the rotational speed difference between the upper and lower disks. Also,
Since the cylindrical body is pressed against the side wall of the guide groove by this sliding force, the cylindrical body slides on the side wall of the guide groove while being processed, and a special mechanism for moving the cylindrical body is not required. In addition, adjustment of the material of the upper and lower disks and the rotation speed difference,
By selecting the processing fluid to be supplied, adding fine abrasive powder, etc., it is possible to set the conditions for the amount of cutting to obtain the target surface roughness. A cylindrical body having a difference or an outer diameter surface roughness can be obtained.

Further, according to the present invention, the same processing is repeated a plurality of times so that the difference between the outer diameters in the lot or the outer surface of the outer diameter surface reaches a target value. Is also good. In the case where the difference between the outer diameters is large, the required accuracy cannot be obtained by processing in one pass, so that this method according to claim 3 is effective. In other words, the cylinder discharged from the guide groove is circulated an appropriate number of times and the processing is repeated, thereby making it possible to produce a cylinder having a target high-precision outer diameter dimensional difference. Also, if the surface roughness before processing is rough, the target surface roughness may not be achieved by one-pass processing. However, even in such a case, the target surface roughness is obtained by repeating the processing a plurality of times. be able to.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating the principle of a processing apparatus according to the present invention, and a dashed line O-
An upper disk 1 and a lower disk 2 rotating in opposite directions on a horizontal plane with O as a rotation center, and a holding plate 3 fixedly arranged between the upper disk 1 and the lower disk 2 are illustrated. FIG.
As shown in FIG. 2, the holding plate 3 is substantially annular in plan view, and has a plurality of guide grooves 4 formed in the radial direction.
The guide groove 4 is a portion through which the cylindrical body 5 to be processed passes, and has a groove width h slightly larger than the diameter d of the cylindrical body 5.
Are formed at a predetermined angle a with respect to the radius line r. Also, of the holding plate 3, the upper disk 1
The thickness t of the thin portion sandwiched between the lower disk 2 and the lower disk 2 is formed to be thinner than the diameter d of the cylindrical body 5 so as not to contact the upper and lower disks 1 and 2 (FIG. 3A).

A flexible supply pipe 6 is connected to the guide groove 4 of the holding plate 3, and the cylindrical body 5 is continuously supplied through the supply pipe 6. Further, the cylindrical body 5 is continuously supplied from the parts feeder 7. In FIG. 1, the supply pipe 6 is provided on the inner diameter side of the holding plate 3, and the cylindrical body 5 is moved from the inner circumference side to the outer diameter side of the holding plate 3. If the rotation direction of the cylinder 5 is reversed, the cylindrical body 5
Can also be moved from the outer peripheral side toward the inner peripheral side.

When operating the processing apparatus having the above structure, a uniform load P is applied on the circumference of the upper disk 1 so that a uniform load acts on the cylindrical body 5 filled in the guide groove 4. Then, the upper and lower disks 1 and 2 are rotated at different rotational speeds in opposite directions while supplying the machining liquid between the upper and lower disks 1 and 2. As described above, in the present apparatus, it is necessary to rotate the upper and lower disks 1 and 2 in opposite directions, and to provide a difference in the rotation speed. Alternatively, a rotational force may be applied to only one of the upper and lower disks 1 and 2 and the other may be driven. Since the guide groove 4 is inclined with respect to the radius line r, when the moving amount of the disk on the driving side is L1, the rotation distance of the cylindrical body 5 corresponding thereto is L5, and the moving amount L2 on the driven side is L2.
Is shorter than L5, a difference corresponding to the inclination angle a of the guide groove occurs in the rotational speed of the upper and lower disks 1 and 2 (see FIG. 5).

In any case, since the rotational speeds of the upper and lower disks 1 and 2 are not the same, for example, as shown in FIG.
In a state where the upper disk 1 rotates in the left direction M1 and the lower disk 3 rotates in the right direction M2, and the rotation speed of the lower disk 2 is higher than the rotation speed of the upper disk 1, the cylindrical body 5 rotates to the right of the guide groove 4 while rotating. It will be pressed against the wall surface 41 by the force of F1. And
Since the guide groove 4 is inclined by a predetermined angle a with respect to the radius line r, as shown in FIG.
One component force F2 is generated, and a sliding motion that moves in the guide groove 4 occurs. By this sliding movement, the cylindrical body 5
Moves in the guide groove 4 in the radial direction, and the cylindrical body 5 is automatically and continuously processed and discharged from the guide groove 4. That is, when the cylindrical body 5 is supplied from the parts feeder 7 to the guide groove 4 via the supply pipe 6, fine cutting is continuously performed.

The opposing surfaces 1a and 2a of the upper and lower disks 1 and 2 are
If it is formed with good flatness accuracy, among the plurality of cylindrical bodies 5 sandwiched between the upper and lower disks 1 and 2, those having a larger outer diameter receive a larger load than those having a smaller outer diameter during machining. The amount of cutting increases, and the external dimensions are automatically made uniform.
When the difference between the outer diameters is large, the required accuracy cannot be obtained by one-pass machining. Therefore, as shown by a dotted line in FIG. By returning to the feeder 7 and processing by circulating a plurality of times, it is possible to produce a cylindrical body having a target high-precision outer diameter dimensional difference.

As for the surface roughness, the relationship between the surface roughness and the cut amount is deeply related, and the smaller the cut amount of the cylindrical body to be processed, the smaller the surface roughness, and a good surface can be obtained. It is also possible to set the conditions for the amount of cutting to achieve the target surface roughness by adjusting the material of the upper and lower disks 1 and 2 and the difference in rotational speed, selecting the processing fluid to be supplied, and adding fine abrasive powder. By setting appropriate conditions, a cylindrical body having a target outer surface roughness can be obtained. If the target surface roughness cannot be obtained by one-pass processing because the surface roughness before processing is rough, a circular body having the target surface roughness is produced by performing circulation processing a plurality of times as in the case of the difference in outer diameter dimensions. be able to. In addition, when there is crowning,
By selecting and using both or one of the two materials having a certain degree of elasticity, it is possible to obtain a target surface roughness up to the crowning portion.

FIG. 4 shows an apparatus according to an embodiment of the present invention, in which a sectional structure on one side from a rotation center line OO is schematically shown. As shown, the device of this embodiment has three bearings 1
0, 11, 12 are provided, the inner ring side of each of the bearings 10, 11, 12 is fixed, and the outer ring side is rotated. That is, in the device shown in FIG. 4, the upper and lower pulleys 13 and 14 that rotate in the opposite direction by a drive belt (not shown), the upper and lower disks 15 and 16 that rotate in the opposite direction corresponding to the pulleys 13 and 14, and the pulleys 13 and The transmission members 17 and 18 for transmitting the rotation of 14 to the disks 15 and 16, the rotation holding member 19 and the positioning members 20 and 21 rotate. As is apparent from the dimensional difference between the upper and lower pulleys 13, 14, the upper and lower disks 15, 16 are rotating at different speeds.

On the other hand, the inner ring side of each of the bearings 10, 11, 12 will be described.
Is fitted, and a substantially cylindrical central guide member 23 is screwed around the upper periphery of the shaft member 22. The center guide member 23 is securely held on the upper portion of the shaft member 22 by screwing the fixing screw 24 onto the inner periphery of the upper portion of the shaft member 22. The central guide member 23 is provided with a plurality of communication holes 23a, 23b.
Is formed radially outward, and the supply pipe 24 is fitted into the communication hole 23a through the communication hole 23b. Then, the cylindrical body is supplied by moving in the supply pipe 24. In this embodiment, the supply pipe 24 is formed by winding a metal wire in a coil shape, has flexibility, and allows the workpiece to move smoothly in the axial direction.

A substantially annular holding plate 26 is fitted on the outer side of the central guide member 23 in the circumferential direction together with the auxiliary member 25.
In the substantially annular holding plate 26, the communication hole 23 of the central guide member 23 is provided.
A plurality of guide grooves 27 are formed in the radial direction corresponding to a, and the cylindrical body supplied from the supply pipe 24 moves while being processed. The shape and structure of the guide groove 27 are as described with reference to FIGS.
A receiving tray 31 is provided on the outside.

An inner ring of the bearing 10 is loosely mounted on the upper portion of the central guide member 23 in the axial direction so as to be movable in the axial direction. Further, the pressing member 30 is loosely fitted so as to be movable, and a tightening screw 29 is screwed therein. The conical disk spring 28 is compressed by the tightening screw 29. Disc spring
28 is for applying an appropriate load to the upper disk 15, and by changing the screwing amount of the tightening screw 29, the (pressing member
30, the load on the upper disk 15 is adjusted from the inner ring to the outer ring of the bearing 10 and further via the transmission member 17).
The apparatus of the present embodiment has the above configuration,
15,16 rotate at different speeds in opposite directions, guide grooves
Since the cylinder 27 is inclined by a predetermined angle a with respect to the radius line, the cylindrical body can be automatically discharged while being ground without using a special transport mechanism.

Although the preferred embodiments of the present invention have been specifically described above, they are merely illustrative examples and do not limit the present invention. That is, the gist of the present invention is to provide a holding member provided with a guide groove penetrating in the radial direction between upper and lower disks having flat opposed surfaces, and to supply a cylindrical body to the guide groove, and to provide the upper and lower disks with the upper and lower disks. While applying a load between the outer diameter surface of the cylindrical body and fixing the holding member,
Since the upper and lower disks are rotated in opposite directions, for example, the cylindrical body may be moved by tilting the upper and lower disks 15, 16 and the holding plate 26 downward.

[0019]

As described above, according to the present invention,
High-precision rollers can be made in large quantities and at low cost.

[Brief description of the drawings]

FIG. 1 is a principle diagram for explaining the present invention.

FIG. 2 illustrates a planar shape of a holding plate.

FIG. 3 is a diagram illustrating a relationship between a cylindrical body and a holding plate.

FIG. 4 is a schematic sectional view illustrating an embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating the operation of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper disk 2 Lower disk 1a, 2a Opposing surface 4 Guide groove 3 Holding member (holding plate)

Claims (4)

[Claims] Claims: 1. An upper and lower disk having flat opposing surfaces,
A holding member having a guide groove penetrating in the radial direction is provided, and a cylindrical body is supplied to the guide groove, and a load is applied between the upper and lower disks and an outer diameter surface of the cylindrical body to fix the holding member. On the other hand, a method of processing an outer diameter surface of a cylindrical body, in which the upper and lower disks are rotated in opposite directions. 2. The processing method according to claim 1, wherein a difference is provided between the rotation speeds of the upper and lower disks, and the guide groove is inclined at a predetermined angle with respect to a radius line of the holding member. 3. The processing method according to claim 2, wherein the same processing is repeated a plurality of times so that a difference between outer diameters in a lot or a surface roughness of an outer diameter surface reaches a target value. 4. Between upper and lower disks having flat opposing surfaces,
A holding member having a guide groove penetrating in the radial direction is provided, and a cylindrical body before processing is supplied to the guide groove, and a load is applied between the upper and lower disks and an outer diameter surface of the cylindrical body, and the holding is performed. A cylindrical body formed by grinding an outer diameter surface of the upper and lower disks so as to rotate in opposite directions while fixing the member.