JP2008128403A - Plastic molded product and rolling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plastic molded product usable as a component of a rolling device with excellent wear resistance and lubricity, and also provide a rolling device excellent in wear resistance and lubricity. <P>SOLUTION: An angular ball bearing comprises an inner ring 1, an outer ring 2, a plurality of rolling elements 3 disposed between both raceway surfaces thereof to freely roll, and a retainer 4 for retaining the rolling elements 3 between both the raceway surfaces. The retainer 4 is formed of a polyether ether ketone resin, and subjected to impregnation treatment by bringing it into contact with a solved matter of supercritical carbon dioxide and an extreme pressure agent and removing only supercritical carbon dioxide of the penetrated extreme pressure agent and supercritical carbon dioxide. By such impregnation treatment, the extreme pressure agent is impregnated in a part 100 μm deep from the surface of the retainer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plastic molded product and a rolling device used as components of a rolling device such as a rolling bearing, a linear guide device, a ball screw, a linear motion bearing, and an XY stage.

  As a method for modifying a plastic molded product using supercritical carbon dioxide, for example, there is one disclosed in Patent Document 1. This method for modifying a plastic molded article includes a step of immersing the plastic molded article in supercritical carbon dioxide containing a lubricating oil to allow the lubricant and carbon dioxide to penetrate into the plastic molded article, And a step of removing only carbon dioxide from the lubricating oil and carbon dioxide that have permeated the water.

Thus, when the surface layer portion of the plastic molded product is impregnated with the lubricating oil, excellent lubricity is imparted to the plastic molded product. Therefore, if a plastic molded product impregnated with lubricating oil is used as a component of a rolling device such as a rolling bearing, the rolling device has excellent lubricity and durability (see Patent Document 2).
JP 2005-60473 A JP 2005-299923 A

However, since rolling bearings used for machine tools and the like are used under high-speed rotation conditions such that the dmn value exceeds 1.4 million, it is desired that the rolling bearings have excellent lubricity and wear resistance.
SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a plastic molded article that solves the problems of the prior art as described above and that is excellent in wear resistance and lubricity and can be used as a component of a rolling device. Another object of the present invention is to provide a rolling device that is excellent in wear resistance and lubricity.

  In order to solve the above problems, the present invention has the following configuration. That is, the plastic molded product according to claim 1 of the present invention has an inner member having a raceway surface on the outer surface and a raceway surface opposite to the raceway surface of the inner member, and is disposed on the outer side of the inner member. A plastic molded product used as a component part of a rolling device comprising: an outer member that is formed, and a plurality of rolling elements that are arranged so as to be capable of rolling between the raceway surfaces, the supercritical fluid and the pole The supercritical fluid and the extreme pressure additive are infiltrated by contacting the compatibilizer with the pressure additive, and the supercritical fluid is removed by removing only the supercritical fluid from the permeated supercritical fluid and extreme pressure additive. It is impregnated, and an extreme pressure additive is impregnated in a portion from the surface to a depth of 100 μm.

  According to a second aspect of the present invention, there is provided a plastic molded product comprising an inner member having a raceway surface on an outer surface and a raceway surface facing the raceway surface of the inner member, and is disposed outward of the inner member. A plastic molded product used as a component part of a rolling device comprising: an outer member that is formed, and a plurality of rolling elements that are arranged so as to be capable of rolling between the raceway surfaces, the supercritical fluid and the pole The supercritical fluid and the extreme pressure additive are infiltrated by contacting the compatibilizer with the pressure additive, and the supercritical fluid is removed by removing only the supercritical fluid from the permeated supercritical fluid and extreme pressure additive. It is impregnated, and an extreme pressure additive is impregnated in a portion from the surface to a depth of 20 μm.

Furthermore, the plastic molded article of claim 3 according to the present invention is characterized in that, in the plastic molded article of claim 1 or claim 2, the supercritical fluid is supercritical carbon dioxide.
Furthermore, the plastic molded product of Claim 4 which concerns on this invention is comprised with the crystalline polymer in the plastic molded product as described in any one of Claims 1-3.

Furthermore, the plastic molded product according to claim 5 of the present invention is the plastic molded product according to claim 4, wherein the crystalline polymer is polyethylene, polyoxymethylene, polyvinylidene fluoride, polyamide 6, polyamide 46, polyamide. 66, at least one of polyphenylene sulfide and polyetheretherketone.
Furthermore, the plastic molded article according to claim 6 of the present invention is the plastic molded article according to any one of claims 1 to 5, wherein the extreme pressure additive is a metal dialkyldithiophosphate or a metal dialkyldithiocarbamate. , And at least one of naphthenates.

Furthermore, the rolling device according to claim 7 of the present invention includes an inner member having a raceway surface on the outer surface, and a raceway surface facing the raceway surface of the inner member, and is disposed outward of the inner member. A rolling device comprising: an outer member that is formed, and a plurality of rolling elements that are arranged to freely roll between the both raceway surfaces. At least one of the components is any one of claims 1 to 6. It is comprised with the plastic molded product of description.
Furthermore, the rolling device according to an eighth aspect of the present invention is the rolling device according to the seventh aspect, wherein the rolling device is an angular ball bearing or a cylindrical roller bearing.

Such a plastic molded article has excellent wear resistance and lubricity because the extreme pressure additive is impregnated in a portion from the surface to a predetermined depth. Even if the extreme pressure additive is impregnated beyond a predetermined depth, the wear resistance and lubricity are not improved, and the cost is increased and the plastic molded product is easily deformed and the strength is reduced.
The present invention can be applied to various rolling devices. For example, a rolling bearing, a linear guide device, a ball screw, a linear motion bearing, an XY table, and the like.

Further, the inner member in the present invention means an inner ring when the rolling device is a rolling bearing, a screw shaft when the ball screw is also used, a guide rail when the linear guide device is used, and a linear motion bearing. Means each axis. The outer member is the outer ring when the rolling device is a rolling bearing, the nut when it is a ball screw, the slider when it is a linear guide device, and the outer cylinder when it is also a linear bearing. Each means.
Furthermore, the component in this invention means the component which comprises a rolling device, for example, an inner member, an outer member, a rolling element, a separator, a holder | retainer, and a sealing device are mention | raise | lifted.

  The plastic molded product of the present invention is excellent in wear resistance and lubricity, and can be used as a component of a rolling device. The rolling device of the present invention is excellent in wear resistance and lubricity.

DESCRIPTION OF EMBODIMENTS Embodiments of a plastic molded product and a rolling device according to the present invention will be described in detail with reference to the drawings.
[About impregnation with extreme pressure additive]
The impregnation treatment with the extreme pressure additive for the plastic molded product used as a component of the rolling device includes an immersion treatment process and an evaporation removal process. The immersion treatment step is a step of immersing the plastic molded article in supercritical carbon dioxide containing an extreme pressure additive. Carbon dioxide in the supercritical state becomes compatible with the extreme pressure additive and penetrates from the surface of the plastic molded product to the inside.

  To explain with a specific example, a dried plastic molded product and an extreme pressure additive are placed in a pressure vessel, and carbon dioxide is further filled until the internal pressure becomes 4.5 to 6.5 MPa. And the temperature in a pressure vessel is raised more than a critical temperature, maintaining an internal pressure more than a critical pressure with a pressure reducing valve. Supercritical carbon dioxide is carbon dioxide in a region having a temperature higher than the critical temperature and a pressure higher than the critical pressure. Incidentally, the critical temperature of carbon dioxide is 31 ° C., and the critical pressure is 72.8 atm (7.38 MPa).

  The immersion temperature in the immersion treatment step is not less than the critical temperature of carbon dioxide, more preferably not less than the critical temperature of carbon dioxide and less than the melting point of the resin constituting the plastic molded product. Further, when the temperature of the resin exceeds the glass transition temperature, the free volume increases until the micro-brown motion of the molecular main chain becomes possible, and the carbon dioxide in the supercritical state becomes more easily penetrated into the plastic molded product. Therefore, it is preferable that the immersion temperature in the immersion treatment process is equal to or higher than the glass transition point of the resin constituting the plastic molded product.

Further, the pressure in the immersion treatment step is equal to or higher than the critical pressure of carbon dioxide, and a higher pressure is preferable because the penetration degree of supercritical carbon dioxide into the resin is improved and the efficiency of reforming is improved. However, since it is necessary to make it possible to withstand the high pressure of an apparatus used in the immersion treatment process (hereinafter referred to as an immersion treatment apparatus), the immersion treatment apparatus becomes large and expensive. Therefore, in consideration of the operability and equipment costs of the immersion treatment apparatus, the pressure is suitably in the range of 100 to 300 atmospheres (10.13 to 30.4 MPa).
Furthermore, the immersion time in the immersion treatment process is not particularly limited, and is appropriately set in consideration of the thickness and size of the plastic molded product.

  Next, the evaporation removal process will be described. The apparatus used for the evaporation removal process (hereinafter referred to as the evaporation removal apparatus) is set to a temperature lower than the critical temperature of carbon dioxide (for example, 30 ° C.) and lower than the critical pressure, and then gradually removed to remove the carbon dioxide. Slowly lower the pressure inside to return to atmospheric pressure. As a result, only the carbon dioxide of the extreme pressure additive and carbon dioxide that has penetrated into the plastic molded product is evaporated and removed, and the extreme pressure additive remains in the plastic molded product.

  When almost all of the carbon dioxide in the evaporative removal apparatus is evaporated, only the extreme pressure additive remains in the evaporative removal apparatus, and the plastic molded product is taken out. At this time, if necessary, the extreme pressure additive adhering to the surface of the plastic molded product may be removed by washing. Thereafter, the carbon dioxide can be removed more completely by holding it in a vacuum desiccator or the like for a certain period (for example, 10 days).

  By the two steps as described above, the molecules of the extreme pressure additive penetrate into the plastic molded product, and exist stably in the free volume between the molecules of the resin. As a result, unlike the so-called simple impregnation treatment, in which the plastic molded product is immersed in an extreme pressure additive under conditions such as high temperature and high pressure, it is not limited to the vicinity of the surface of the plastic molded product, but is relatively far into the interior. Pressure additive penetrates. Since the extreme pressure additive is present in the original free volume, the extreme pressure additive hardly oozes out to the outside, and the reforming effect lasts semipermanently and at the same time the mechanical strength decreases. There is almost no possibility of causing.

  The impregnation amount of the extreme pressure additive varies depending on conditions such as the immersion temperature, pressure, and immersion time, but the influence of the extreme pressure additive on the impregnation amount is the largest in the above three conditions. Then, the order of immersion time and pressure. If these conditions are set according to the thickness and size of the plastic molded product, the depth of impregnation with the extreme pressure additive can be controlled.

  The depth impregnated with the extreme pressure additive can also be controlled by changing the operation procedure of the impregnation treatment with the extreme pressure additive. For example, in the above-described example, after evaporating and removing the inside of the evaporation removing apparatus below the critical temperature of carbon dioxide and below the critical pressure in the evaporation removing step, the carbon dioxide is gradually discharged to slowly return the pressure in the evaporation removing apparatus to atmospheric pressure. The operation procedure was, but the pressure inside the evaporative removal device was suddenly lowered to atmospheric pressure in a short time of about 30 seconds, so that the temperature inside the evaporative removal device was drastically lowered and the inside of the evaporative removal device was in a supercritical state. If the operating procedure is changed from normal to normal, the depth impregnated with the extreme pressure additive can be changed. Moreover, the depth which an extreme-pressure additive impregnates can further be changed by further combining the method of impregnating an extreme-pressure additive to the inside of a plastic molded product.

[About supercritical fluids]
In the present invention, various supercritical fluids can be used. For example, carbon dioxide, nitrogen dioxide, ammonia, ethane, propane, ethylene, methanol, ethanol and the like can be mentioned. However, carbon dioxide is most preferred because it becomes a supercritical fluid under relatively mild conditions, and is non-toxic and non-flammable.

[Extreme pressure additive]
The kind of extreme pressure additive that can be used in the present invention is not particularly limited, and examples thereof include metal dithiophosphate, metal dithiocarbamate, and naphthenate.
When the metal dithiophosphate is a metal dialkyldithiophosphate, the alkyl group preferably has 4 to 20 carbon atoms. Examples of metal dithiophosphates include zinc dimethyldithiophosphate, zinc butylisooctyl dithiophosphate, zinc di (4-methyl-2-pentyl) dithiophosphate, zinc di (tetrapropenylphenyl) dithiophosphate, zinc (2-Ethyl-1-hexyl) dithiophosphate, zinc isooctyl dithiophosphate, zinc ethylphenyl dithiophosphate, zinc amyl dithiophosphate, zinc dihexyl dithiophosphate. The type of metal is not limited to zinc (Zn), and lead (Pb), cadmium (Cd), antimony (Sb), molybdenum (Mo), and the like are also preferable.

  When the metal dithiocarbamate is a metal dialkyldithiocarbamate, the alkyl group preferably has 4 to 20 carbon atoms. Examples of metal dithiocarbamate include zinc dimethyldithiocarbamate, zinc butylisooctyl dithiocarbamate, zinc di (4-methyl-2-pentyl) dithiocarbamate, zinc di (tetrapropenylphenyl) dithiocarbamate, zinc (2-ethyl- 1-hexyl) dithiocarbamate, zinc isooctyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc amyldithiocarbamate, zinc dihexyldithiocarbamate. The type of metal is not limited to zinc (Zn), and lead (Pb), cadmium (Cd), antimony (Sb), molybdenum (Mo), and the like are also preferable.

Furthermore, the naphthenic acid salt is preferably a metal salt of naphthenic acid, and an example thereof is lead naphthenate.
The type of extreme pressure additive to be used may be selected according to the type of extreme pressure additive in the lubricant used when lubricating the resin component.

[Resin]
In the present invention, the type of resin constituting the component is not particularly limited, but as a resin to which the impregnation treatment with an extreme pressure additive can be suitably applied, the glass transition temperature (Tg) is a criticality of a supercritical fluid. Those higher than the temperature are preferred. Examples thereof include polyethylene, polyoxymethylene, polyvinylidene fluoride, polyamide 6, polyamide 66, polyamide 46, aromatic polyamide, polyphenylene sulfide, polyether ether ketone, and the like.

  These resins may contain fibrous fillers such as glass fibers, carbon fibers, and aramid fibers, and whiskers such as potassium titanate whiskers and aluminum borate whiskers. Moreover, you may contain additives, such as a heat stabilizer and antioxidant. However, among the above-mentioned resins, general-purpose resins often contain the above-mentioned additives, and it is expected that the additives will be extracted depending on the conditions of the impregnation treatment of the extreme pressure additive. And be careful with pressure.

Next, an example will be described in which a plastic molded article that has been impregnated with an extreme pressure additive as described above is used as a component of an angular ball bearing or a cylindrical roller bearing.
[First embodiment]
FIG. 1 is a cross-sectional view showing a structure of an angular ball bearing which is an embodiment of a rolling device according to the present invention.

The angular ball bearing shown in FIG. 1 includes an inner ring (inner member) 1 having a raceway surface on an outer peripheral surface, and an outer ring (outer side) having a raceway surface opposite to the raceway surface of the inner ring 1 and disposed outside the inner ring 1. Member) 2, a plurality of rolling elements (balls) 3 arranged so as to be able to roll between both raceway surfaces, and a cage 4 that holds the rolling element 3 between both raceway surfaces.
The cage 4 is an outer ring guide type. Both end portions in the axial direction of the inner peripheral surface of the outer ring 2 other than the raceway surface serve as guide surfaces 6 of the cage 4, and the radial movement of the cage 4 is restricted by the outer ring 2.

  Among the components of the angular ball bearing, the inner ring 1, the outer ring 2, and the rolling element 3 are made of steel such as martensitic stainless steel SUS440C. The angular ball bearing retainer 4 is manufactured by injection molding a polyetheretherketone resin (PEEK450G manufactured by Victrex Co., Ltd.) and subjected to the following impregnation treatment with an extreme pressure additive. Yes. In other words, this is a treatment in which a compatibilized product of supercritical carbon dioxide and an extreme pressure additive is brought into contact and only supercritical carbon dioxide is removed from the permeated extreme pressure additive and supercritical carbon dioxide.

  Here, the detailed procedure of the impregnation process will be described. First, molybdenum dithiocarbamate MoDTC (Sakura Denki Kogyo Co., Ltd. Sakura Lube 515), which is an extreme pressure additive, and a cage were placed in a pressure vessel of a supercritical carbon dioxide test apparatus manufactured by Pressure Glass Industrial Co., Ltd. . Furthermore, carbon dioxide was filled into the pressure vessel from the liquefied carbon dioxide cylinder using a pump until the internal pressure of the pressure vessel reached 6.5 MPa.

  Next, the internal temperature of the pressure vessel was raised to 150 ° C. while maintaining the internal pressure of the pressure vessel at 20 MPa using a pressure reducing valve. After holding at 150 ° C. for 1 hour, it was allowed to cool to 30 ° C., the internal pressure was returned to atmospheric pressure, and the cage was taken out from the pressure vessel. By such impregnation treatment, the extreme pressure additive penetrates into the surface layer portion of the cage, and wear resistance and lubricity are imparted, so that the wear resistance and lubricity of the angular ball bearing are improved.

[Second Embodiment]
FIG. 2 is a sectional view showing the structure of an angular ball bearing which is a second embodiment of the rolling device according to the present invention. In FIG. 2, the same reference numerals as those in FIG. 1 are assigned to the same or corresponding parts as in FIG.
The structure of the angular ball bearing in FIG. 2 is substantially the same as that of the angular ball bearing of the first embodiment, and the cage 4 is an outer ring guide type. One end of the direction is a guide surface 6 of the cage 4, and the radial movement of the cage 4 is restricted by the outer ring 2.

  This cage 4 is manufactured by injection molding a polyphenylene sulfide resin (Fortron 2130A1 manufactured by Polyplastics Co., Ltd.) containing 30% by mass of carbon fiber, and the same impregnation treatment as that in the first embodiment is performed. Has been. Therefore, the same effect as that of the angular ball bearing of the first embodiment can be obtained.

[Third embodiment]
FIG. 3 is a sectional view showing the structure of an angular ball bearing which is a third embodiment of the rolling device according to the present invention. In FIG. 3, the same or corresponding parts as those in FIG. 1 are denoted by the same reference numerals as those in FIG.
The structure of the angular ball bearing of FIG. 3 is substantially the same as that of the angular ball bearing of the first embodiment, but the cage 4 is an inner ring guide type. Both ends in the axial direction of the outer circumferential surface of the inner ring 1 other than the raceway surface serve as guide surfaces 6 of the cage 4, and the radial movement of the cage 4 is restricted by the inner ring 1.

  This cage 4 is manufactured by injection molding polyamide 66 (UBE Nylon 2020GU6 manufactured by Ube Industries, Ltd.) containing 30% by mass of glass fiber, and the internal temperature of the pressure vessel is 100 ° C. Except for this, the same impregnation treatment as in the first embodiment is performed. Therefore, the same effect as that of the angular ball bearing of the first embodiment can be obtained.

[Fourth embodiment]
FIG. 4 is a sectional view showing the structure of a single row cylindrical roller bearing which is a fourth embodiment of the rolling device according to the present invention.
The single-row cylindrical roller bearing shown in FIG. 4 has an inner ring (inner member) 1 having a raceway surface on the outer peripheral surface, and an outer ring having a raceway surface opposite to the raceway surface of the inner ring 1 and disposed outside the inner ring 1 ( (Outer member) 2, a plurality of rolling elements (cylindrical rollers) 3 arranged so as to be able to roll between both raceway surfaces, and a cage 4 that holds the rolling element 3 between both raceway surfaces. .

The cage 4 is an outer ring guide type. Both end portions in the axial direction of the inner peripheral surface of the outer ring 2 other than the raceway surface serve as guide surfaces 6 of the cage 4, and the radial movement of the cage 4 is restricted by the outer ring 2.
Of the components of the single row cylindrical roller bearing, the inner ring 1, the outer ring 2, and the rolling element 3 are made of steel such as martensitic stainless steel SUS440C. Further, the cage 4 of this single row cylindrical roller bearing is manufactured by injection molding of a thermoplastic polyimide resin (AURUM JCN3030 manufactured by Mitsui Chemicals) containing 30% by mass of carbon fiber. Except for the internal temperature being 100 ° C., the same impregnation treatment as in the first embodiment is performed. Therefore, the same effect as the angular ball bearing of the first embodiment can be obtained.

[Fifth embodiment]
FIG. 5 is a sectional view showing the structure of a double row cylindrical roller bearing which is a fifth embodiment of the rolling device according to the present invention.
The structure of the double row cylindrical roller bearing of FIG. 5 is substantially the same as the cylindrical roller bearing of the fourth embodiment except that double row cylindrical rollers are provided, but the cage 4 is a rolling element guide type. The outer peripheral surface of the cylindrical roller 3 is a guide surface 6 of the cage 4, and the radial movement of the cage 4 is restricted by the cylindrical roller 3.

  Among the components of the double row cylindrical roller bearing, the inner ring 1, the outer ring 2, and the rolling element 3 are made of steel such as martensitic stainless steel SUS440C. The cage 4 of this double row cylindrical roller bearing is manufactured by injection molding a polyphenylene sulfide resin (Fortron 2130A1 manufactured by Polyplastics Co., Ltd.) containing 30% by mass of carbon fiber. The impregnation treatment similar to the form is performed. Therefore, the same effect as that of the angular ball bearing of the first embodiment can be obtained.

  This double row cylindrical roller bearing has a structure in which the cage 4 does not contact the inner ring 1 and the outer ring 2. In such a case, since the weight of the cage 4 is applied between the pocket of the cage 4 and the cylindrical roller 3, the lubricating oil film in that portion tends to be cut easily and wear tends to increase. Therefore, by using the cage 4 subjected to the impregnation treatment as described above, wear resistance and lubricity are further improved.

  In the first to fifth embodiments, angular ball bearings and cylindrical roller bearings have been described as examples of rolling devices. However, the present invention is applicable to various types of rolling bearings. Can do. For example, radial type rolling bearings such as deep groove ball bearings, self-aligning ball bearings, tapered roller bearings, needle roller bearings, self-aligning roller bearings, and thrust type rolling bearings such as thrust ball bearings and thrust roller bearings. is there. The present invention can be applied not only to rolling bearings but also to various other types of rolling devices. For example, a ball screw, a linear guide device, a linear motion bearing, or the like.

〔Example〕
Hereinafter, the present invention will be described more specifically with reference to examples.
A polyphenylene sulfide resin (Fortron 2130A1 manufactured by Polyplastics Co., Ltd.) was injection-molded to produce a disc having a diameter of 30 mm and a thickness of 3 mm. In addition, since there exists a possibility of obstructing the observation of the impregnation state inside a disc, polyphenylene sulfide resin which does not contain fillers, such as carbon fiber, was used. Then, the same impregnation treatment as in the third embodiment was applied to the disc, and impregnated with molybdenum dithiocarbamate (Sakura Denki Kogyo Co., Ltd. Sakura Lube 515) as an extreme pressure additive.

Next, the impregnated disc was cut and a cross section having a thickness of 1.5 mm was produced by a microtome. And the distribution situation of the depth direction of the molybdenum impregnated in the disk was investigated by analyzing the section with a scanning analytical electron microscope (SEM-EDX). The analysis results are shown in FIG.
From this figure, it can be seen that molybdenum exists in a portion from the surface to a depth of 100 μm. And it turns out that molybdenum exists in high concentration in the part from the surface to a depth of 20 μm.

  Next, the evaluation result of wear resistance will be described. A polyphenylene sulfide resin (Fortron 2130A1 manufactured by Polyplastics Co., Ltd.) containing 30% by mass of carbon fiber was injection-molded to produce a disc having a diameter of 30 mm and a thickness of 3 mm. Then, the same impregnation treatment as that in the first embodiment was performed on the disc, and impregnated with molybdenum dithiocarbamate (Sakura Rube 515 manufactured by Asahi Denka Kogyo Co., Ltd.) which is an extreme pressure additive.

  On this disk, 1 μL of poly α-olefin oil was dropped, and a SUJ2 columnar member having a diameter of 6 mm was placed thereon such that the cylindrical surface was in contact with the plate surface of the disk. Then, while applying a load of 20 N from above, the cylindrical member was rotated for 1.5 hours at a rotational speed of 6000 to 12000 rpm (sliding speed of 1.26 to 3.77 mm / s), and then the amount of wear of the disk Was measured. The results are shown in the graph of FIG.

  As can be seen from this graph, the disc subjected to the impregnation treatment had less wear than the untreated product. In particular, at the highest sliding speed of 3.77 mm / s, the test was stopped because the untreated product reached the limit wear amount of 1000 μm, whereas the impregnated disk had a wear amount of 70 μm. There were few. As described above, since the impregnation treatment exhibits good wear resistance and lubricity under high-speed rotation conditions, it is suitable for a rolling bearing that supports the main shaft of a machine tool.

It is sectional drawing which shows the structure of the angular ball bearing which is 1st embodiment of the rolling device which concerns on this invention. It is sectional drawing which shows the structure of the angular ball bearing which is 2nd embodiment of the rolling device which concerns on this invention. It is sectional drawing which shows the structure of the angular ball bearing which is 3rd embodiment of the rolling device which concerns on this invention. It is sectional drawing which shows the structure of the single row cylindrical roller bearing which is 4th embodiment of the rolling device which concerns on this invention. It is sectional drawing which shows the structure of the double row cylindrical roller bearing which is 5th embodiment of the rolling device which concerns on this invention. It is a schematic diagram which shows the distribution condition of the impregnated molybdenum. It is a graph which shows the relationship between the sliding speed and wear amount in an abrasion test.

Explanation of symbols

1 Inner ring 2 Outer ring 3 Rolling element 4 Cage

Claims (8)

An inner member having a raceway surface on the outer surface, an outer member having a raceway surface opposite to the raceway surface of the inner member, and arranged on the outer side of the inner member, and rolling between the both raceway surfaces A plastic molded product used as a component of a rolling device comprising a plurality of freely arranged rolling elements,
By contacting the compatibilized material of the supercritical fluid and the extreme pressure additive to infiltrate the supercritical fluid and the extreme pressure additive, and removing only the supercritical fluid from the infiltrated supercritical fluid and extreme pressure additive. A plastic molded article impregnated with an extreme pressure additive and impregnated with an extreme pressure additive in a portion from the surface to a depth of 100 μm. An inner member having a raceway surface on the outer surface, an outer member having a raceway surface opposite to the raceway surface of the inner member, and arranged on the outer side of the inner member, and rolling between the both raceway surfaces A plastic molded product used as a component of a rolling device comprising a plurality of freely arranged rolling elements,
By contacting the compatibilized material of the supercritical fluid and the extreme pressure additive to infiltrate the supercritical fluid and the extreme pressure additive, and removing only the supercritical fluid from the infiltrated supercritical fluid and extreme pressure additive. A plastic molded article characterized by being impregnated with an extreme pressure additive and impregnated with an extreme pressure additive in a portion from the surface to a depth of 20 μm.   The plastic molded article according to claim 1 or 2, wherein the supercritical fluid is supercritical carbon dioxide.   The plastic molded article according to any one of claims 1 to 3, wherein the plastic molded article is made of a crystalline polymer.   5. The crystalline polymer is at least one of polyethylene, polyoxymethylene, polyvinylidene fluoride, polyamide 6, polyamide 46, polyamide 66, polyphenylene sulfide, and polyether ether ketone. Plastic molded product as described in 1.   The plastic molding according to any one of claims 1 to 5, wherein the extreme pressure additive is at least one of a metal dialkyldithiophosphate, a metal dialkyldithiocarbamate, and a naphthenate. Goods. An inner member having a raceway surface on the outer surface, an outer member having a raceway surface opposite to the raceway surface of the inner member, and arranged on the outer side of the inner member, and rolling between the both raceway surfaces In a rolling device comprising a plurality of freely arranged rolling elements,
A rolling device characterized in that at least one of the components is made of the plastic molded product according to any one of claims 1 to 6.   The rolling device according to claim 7, wherein the rolling device is an angular ball bearing or a cylindrical roller bearing.

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