JP2002349589A - Method of manufacturing bearing filled with polymer lubricant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a polymer lubricant-filled bearing capable of making a stress hardly act from a rolling element onto a polymer lubricant when rotated, capable of preventing damage of the polymer lubricant even in high-speed rotation, and capable of preventing slide from being generated between the rolling element and raceway surfaces of inner.outer rings. SOLUTION: Double-row self-aligning roller bearing 1 is assembled, a raw material 150 of the polymer lubricant is injected thereafter between the inner ring 11 and the outer ring 12 to be solidified under the condition where respective cages 14a, 14b and the respective rolling elements 13 are positioned in a specified position to get symmetric with respect to the axial-directional center C of the bearing 1, using a pair of jigs 2a, 2b abutting to the respective cages 14a, 14b and the respective rolling elements 13 of respective rolling element trains 13a, 13b via a side face opening of the bearing 1, the polymer lubricant 15 after solidified is thereby formed into a symmetrical shape sandwiching the axial-directional center C of the bearing 1, and unnecessary force is made not to act between bearing-constituting members each other in the rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polymer-lubricated bearing, and more particularly, to a polymer-lubricated bearing comprising a double-row self-aligning roller bearing and a polymer lubricant filled between the inner and outer rings. The present invention relates to a method for manufacturing a bearing.

[0002]

2. Description of the Related Art In a rolling bearing, generally, an annular space formed between an inner ring and an outer ring is formed in order to improve a lubricating joint between an inner ring raceway surface and a rolling element or between an outer ring raceway surface and a rolling element. Lubricating oil is supplied or grease is filled. In order to supply or enclose such lubricating oil or grease in the space between the inner and outer rings,
Or, in order to prevent water or foreign matter from entering the space from the outside, a contact-type seal or a labyrinth seal is usually provided in an annular shape to seal or partition the space between the inner ring and the outer ring from the outside. Attached to both ends of the space in the axial direction.

However, in a double-row self-aligning roller bearing in which two rows of raceways are formed on the outer periphery of the inner ring and one raceway is formed on the inner periphery of the outer race in an arc-parallel cross section, When used under certain conditions, the rolling elements may protrude from the outer ring raceway surface and rotate, and in such a self-aligning roller bearing, lubricating oil or Grease may flow out of the bearing.

As one measure against such a case, conventionally, a mixture of a polymer, a lubricating oil or grease is heated and melted in a space formed between an inner ring and an outer ring, and then cooled and solidified. A method of enclosing a so-called polymer lubricant is known (for example, Japanese Patent Application Laid-Open No. 6-50330).
issue). According to this polymer lubricant-enclosed bearing, the rotation of the bearing gradually releases the lubricating oil or grease contained in the polymer and spreads between the raceway surfaces of the inner and outer rings and the rolling elements, thereby providing a good over a long period of time. A lubricated state can be maintained.

[0005] The polymer lubricant used here is usually
A mixture of ultra-high-molecular-weight polyethylene resin and lubricating oil or grease is solidified.When sealed between the inner and outer rings of the bearing, the double-row spherical roller bearing after assembly is oriented horizontally In other words, the above-mentioned mixture is heated and melted in the space between the inner and outer rings, filled and then cooled and solidified in a state where the bearing is laid so that the center axis of the bearing is oriented vertically. Have been.

[0006]

By the way, in order for the rolling bearing to rotate, a gap in the axial direction, that is, an axial gap is required between the inner ring, the rolling element row, and the outer ring, and a double-row self-aligning roller is required. An axial gap is also set in the bearing. A predetermined gap is also set between the pocket of the retainer and the rolling element.

Therefore, as described above, in order to manufacture a polymer lubricant-filled bearing in which a polymer lubricant is accommodated inside a double-row self-aligning roller bearing, the side face of the bearing after assembly is made horizontal in a conventional manner. When the polymer lubricant raw material is injected and solidified between the inner ring and the outer ring in a state along the inner ring and the outer ring, the retainer and the rolling element between the inner ring and the outer ring have their own weights, the lower side surfaces by the respective gaps described above. In this state, the polymer lubricant is molded. In particular, in a self-aligning roller bearing in which the gaps are set large, the drop is large.

When the thus-obtained polymer lubricant-filled bearing is rotated in a normal use state, the polymer lubricant, the rolling elements and the cage are positioned asymmetrically with respect to the axial center of the bearing. Therefore, unnecessary unnecessary force is applied between the bearing components to smoothly rotate the bearing. This unnecessary force hinders the smooth movement of the rolling elements, and easily causes slippage between the rolling elements and the raceway surface. Seizure caused by the slippage and, particularly during high-speed rotation, polymer lubrication There was a problem that the agent was easily damaged.

The present invention has been made in view of such circumstances, and it is difficult for unnecessary force to act between bearing components during rotation, thereby preventing damage to the polymer lubricant during high-speed rotation, It is an object of the present invention to provide a manufacturing method capable of stably obtaining a polymer lubricant-enclosed bearing capable of preventing occurrence of slip between a moving body and a raceway surface.

[0010]

In order to achieve the above-mentioned object, a polymer lubricant-filled bearing of the present invention has two rows of raceways formed on the outer periphery of an inner ring, and has an axially parallel section on the inner periphery of an outer ring. Are formed, and a plurality of rolling elements are held on each of the two rows of raceways of the inner ring by retainers for each row, and the inner raceway surface and the outer raceway are formed. A method of manufacturing a polymer lubricant-enclosed bearing in which a polymer lubricant is contained in a space between the inner ring and the outer ring, of a self-aligning roller bearing arranged to be rotatable with respect to both surfaces, After assembling the bearing including the inner ring, the outer ring, the two cages, and the two rows of rolling elements held by the respective cages, the bearings are applied to the respective cages and the rolling elements via the side openings of the bearings. Using the contacting jig, the axis of each cage and the rolling elements in each row The position in the axial direction in a state of being positioned in prescribed positions symmetrical with respect to the axial center of the bearing, characterized by solidifying by injecting polymer lubricant material between the inner and outer rings.

According to the present invention, when a raw material of a polymer lubricant is injected between an inner ring and an outer ring, a retainer and each rolling element are restrained by a jig. The purpose of the present invention is to eliminate the uneven distribution of the cage and the rolling elements in the bearing due to the existence of the gap and the gravity, thereby achieving the intended purpose.

That is, in a state where double row self-aligning roller bearings are assembled, each retainer and each row of rolling elements face the outside from the opening on both side surfaces thereof, and each retainer and each rolling element from the opening are opened. A jig can be brought into contact with each rolling element, and by using such a jig, each retainer and each row of rolling elements can be positioned at symmetrical positions with respect to the axial center of the bearing. Can be positioned. In the positioning state of each cage and each rolling element, the polymer lubricant material is injected between the inner ring and the outer ring and solidified, so that the solidified polymer lubricant becomes symmetrical with respect to the axial center of the bearing. Unnecessary force does not act between the bearing components during rotation in normal use conditions as in the past, and the occurrence of slippage between the rolling elements and the raceway and the occurrence of breakage of the polymer lubricant, etc. It can be reliably prevented.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are explanatory views of an example of a procedure for manufacturing a polymer lubricant-enclosed bearing by employing the method of the present invention.

First, as shown in FIG.
As well as assembling the double row spherical roller bearing 1, a pair of jigs 2a and 2b also shown in the same sectional view in FIG. 1 and bolts for fastening them (not shown in FIG. 1, see FIG. 3) Prepare The spherical roller bearing 1 has two rows of raceway surfaces 11 on both sides of a bearing center C on the outer periphery.
a and 11b are formed between the inner race 11 and the outer race 12 having one raceway surface 12a that forms an arc shape on the inner periphery in an axially parallel cross section, corresponding to each raceway surface 11a and 11b of the inner race 11. Thus, two rows of rolling element rows 13a and 13b each including a plurality of rolling elements 13
a, 14b, each rolling element 13 has a raceway surface 11a or 11b of the inner race 11 and a raceway surface 1 of the outer race 12
2a so as to roll freely. Each of the retainers 14a and 14b is formed with a plurality of pockets P for retaining the rolling elements 13 at a constant pitch in the circumferential direction. In the figure, reference numeral 16 denotes a guide wheel.

The jigs 2a and 2b have one jig 2a
Female screw 21a at a constant pitch in the circumferential direction near the outer edge
Whereas the other jig 2b has a through hole 21b at a position corresponding to each female screw 21a, and the injection hole 26b of the polymer lubricant raw material is formed only in this jig 2b. Are formed in the same manner as described below, except that is formed.

That is, each of the jigs 2a and 2b has a shape in which holes 22a and 22b are formed in the center of the disk as a whole, and self-centering around the holes 22a and 22b is provided on one end surface side. Cage 1 in a state mounted on roller bearing 1
Annular projections 23a abutting the side surfaces of 4a or 14b,
23b, projections 24a, 24b are formed on the outer peripheral side of the rolling element 13 in a state of being mounted on the self-aligning roller bearing 1 in the same manner. The other end faces are flat faces 25a, 25
b. In each jig 2a, 2b, the projection 23
a and 23b have the same amount of protrusion, and the protrusions 24a and 24b have the same amount of protrusion. Therefore, each rolling element row and each cage positioned by these respective jigs are positioned symmetrically in the axial direction with respect to the axial center C of the bearing.

In pouring the polymer lubricant material into the bearing 1, first, as shown in FIG. 2, one jig 2a is used.
The flat surface 25a is placed on the horizontal surface H with the jig 2a facing down while the abutment is in contact with the side surface of the bearing 1. In this state, one side surface (end surface) of the inner ring 11 and the outer ring 12 of the bearing 1 abuts on the jig 2a, and at the same time, the projection 23a is on the side surface of the one retainer 14a, and the projection 24a is on the retainer 14a. Abuts against the end face of each rolling element 13 of one rolling element row 13a held in the first row. In this state, the polymer lubricant raw material 150 is injected into the gap between the inner ring 11 and the outer ring 12 in a molten state from the side opening of the bearing 1 facing upward.
At this time, the polymer lubricant raw material is injected near the center C of the bearing in the axial direction so as not to enter the raceway surface 11b, and then cooled and solidified, and the rolling elements 13 and the cage 14a on the raceway surface 11a side are cooled. Fix axial position. The reason that the polymer lubricant raw material is prevented from entering the raceway surface 11b is that the polymer lubricant solidified here uses the cage 14 on the raceway surface 11b side.
This is because the positions of b and the rolling elements 13 are not fixed.

Next, as shown in FIG. 3, the other jig 2b is put on the bearing 1 from above, and each through-hole 21b of the jig 2b is placed.
The bolt 2c is connected to the female screw 21a of the jig 2a through
Into the jigs 2a and 2b with the bearing 1 in between.
Are fixed and placed with the jig 2b side down. In this state, the rolling elements 13 of each rolling element row 13a, 13b
And the jigs 2 on both sides of the cages 14a and 14b, respectively.
a and 2b are positioned in contact with the projections 23a and 23b and 24a and 24b, so that the rolling element rows 13a and 13b
b, and the cages 14a and 14b
Is positioned at a position symmetrical with respect to the center C in the axial direction. Next, in this state, the gap between the inner ring 11 and the outer ring 12 is densely filled with the polymer lubricant raw material 150 via the injection hole 26b of the jig 2b, and then cooled to cool the polymer lubricant raw material 150. It is solidified, and the axial position of the rolling element 13 and the retainer 14b on the raceway surface 11b side is fixed.
Thereafter, by removing the jigs 2a and 2b, a polymer lubricant-filled bearing in which the polymer lubricant 15 is accommodated in the space between the inner ring 11 and the outer ring 12 is obtained as shown in FIG.

In the polymer lubricant-filled bearing obtained by the above procedure, the polymer lubricant 15 is applied to each of the cages 14a, 14b and each rolling element 13 of each rolling element row 13a, 13b in the axial direction of the bearing 1. Since it is solidified and molded while being positioned at a symmetrical position with respect to the center C, it is symmetrical on both sides of the axial center C. As a result, when the bearing 1 rotates, no unnecessary force acts between the respective bearing components, the breakage of the polymer lubricant 15 is prevented, and the raceway surfaces 11a, 11b and 1 of the rolling elements 13, the inner ring 11 and the outer ring 12 are prevented.
2a can be prevented from slipping.

[0020]

As described above, according to the present invention, when a polymer lubricant raw material is injected between the inner and outer rings of a double-row self-aligning roller bearing and solidified and molded, a pair of cages and In order to position the rolling elements in each row at positions symmetrical with respect to the axial center of the bearing using jigs, the polymer lubricant solidified and molded between the inner and outer rings is applied to the center of the bearing in the axial direction. The bearings are symmetrical with respect to each other, so that no unnecessary force acts between the bearing components when the bearing rotates. As a result, according to the polymer lubricant-filled bearing obtained by the method of the present invention, it is possible to prevent the polymer lubricant from being damaged even during high-speed rotation, thereby improving the limit rotational speed of the bearing. Since the occurrence of slippage between the rolling elements and the raceways of the inner and outer races can be prevented, seizure resistance can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view of an example of a procedure for manufacturing a polymer lubricant-enclosed bearing by employing the method of the present invention, in which a double row self-aligning roller bearing 1 is assembled and jigs 2a and 2b to be prepared. FIG.

FIG. 2 is an explanatory diagram of an example of a procedure for manufacturing a polymer lubricant-enclosed bearing by employing the method of the present invention, showing a state in which one jig 2a is in contact with one side surface of the bearing 1. .

FIG. 3 is an explanatory view of a state in which the other jig 2b is brought into contact with the other side surface of the bearing from the state of FIG. 2 to be integrally fastened to the jig 2a.

4 is an axially parallel sectional view of the polymer lubricant-enclosed bearing obtained by removing the jigs 2a and 2b after solidifying the polymer lubricant raw material from the state of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Double row self-aligning roller bearing 11 Inner ring 12 Outer ring 13 Rolling element 13a, 13b Rolling element row 14a, 14b Cage 15 Polymer lubricant 2a, 2b Jig 23a, 23b Projection (for contact with retainer) 24a, 24b Projection (For rolling element abutment) C Center of axial direction of bearing 1

Claims (1)

[Claims] 1. A raceway surface having two rows formed on the outer periphery of an inner ring, a raceway surface forming an arc shape on an axially parallel cross section is formed on an inner periphery of the outer ring, and two raceways on the inner ring. A plurality of rolling elements are respectively held by retainers of each row, and the inner ring of the self-aligning roller bearing is arranged so as to roll freely on both the inner ring raceway surface and the outer ring raceway surface. A polymer lubricant-filled bearing in which a polymer lubricant is contained in a space between the inner ring and the outer ring, comprising: the inner ring, the outer ring, two cages, and two rows of rollers held by the cages. After assembling the bearing consisting of the moving body row,
Using a jig that abuts each retainer and each rolling element through the side opening of the bearing, the position of each retainer and each row of rolling elements in the bearing axial direction with respect to the axial center of the bearing is determined. A method for producing a polymer-lubricated encapsulated bearing, characterized in that a polymer-lubricated raw material is injected and solidified between an inner ring and an outer ring in a state where the bearings are positioned at predetermined symmetrical positions.