JPS6345694B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for manufacturing a porous sintered synthetic resin bearing with excellent heat resistance and high speed. [Prior Art] Conventionally, as synthetic resin porous sintered bearings, those mainly made of polyamide resin and lead, or those mainly made of polyacetal resin and thermosetting resin are known. [Problems to be Solved by the Invention] However, these materials are not fully satisfactory in terms of heat resistance and high speed performance, and also have the disadvantage that manufacturing is complicated and dimensional accuracy as a bearing is difficult to obtain. Furthermore, in recent years, the conditions under which bearings are used have become more severe, and there is a problem in that these bearings cannot be used particularly in high-speed, high-temperature environments. In view of the above-mentioned problems, the present invention aims to provide a synthetic resin porous sintered bearing that has excellent heat resistance and high speed performance, is easy to manufacture, and has good dimensional accuracy. [Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention adopts the following technical means, that is, the configuration. That is, 50 to 95 wt% of one or more thermoplastic resins selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, and polyethersulfone resin are mixed with 5 to 50 wt% of a thermosetting resin. base resin,
Alternatively, a mixed powder formed by mixing 5 to 30 parts by weight of a solid lubricant to 100 parts by weight of the base resin, a mixed powder formed by mixing 10 to 50 parts by weight of a reinforcing material to 100 parts by weight of the base resin, the base 5-30% by weight of solid lubricant and 10% by weight of reinforcing material per 100 parts by weight of resin
A mixed powder made by mixing ~50 parts by weight of both in a range where the total amount does not exceed 70 parts by weight is filled into a mold and molded at a molding pressure of 900 to 1600 kg/cm ² to form the desired molded product. After forming, the molded article is heated and sintered in a furnace to a temperature exceeding the melting point of the thermoplastic resin by 0 to 50 degrees Celsius under conditions of continuous or stepwise cumulative temperature increase of 1 to 8 degrees Celsius. This is a method for manufacturing a porous sintered synthetic resin bearing. In the above configuration, the thermoplastic resin that is the main component of the base resin is selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, and polyether sulfone resin, and these resins have excellent heat resistance and can be used individually. These resins can be used alone or as a blend of two or more of these, and the blend can improve the heat resistance, mechanical strength, and self-lubricating properties of the resin itself. The thermosetting resin that is mixed with the thermoplastic resin to form the base resin plays the role of a binder,
The thermoplastic resin used in the present invention has good miscibility with the thermoplastic resin, and the melting point of the thermoplastic resin (here, the melting point of the thermoplastic resin refers to the softening point of a crystalline resin; An example of the melting point of a resin is polyphenylene sulfide resin:
290℃, oxybenzoyl resin: 320℃, polysulfone resin: 200℃, polyethersulfone resin:
The temperature is 230℃. ) Any material that softens at a temperature in the vicinity of ) may be used. In the present invention, good results have been obtained using polyimide resins, phenolic resins, epoxy resins, silicone resins, melamine resins, and the like. The mixing ratio of thermoplastic resin and thermosetting resin is 50 to 95 wt% of thermoplastic resin to 5 to 50 wt% of thermosetting resin, preferably 70 to 90:10 to 30 (wt%).
%) is appropriate. Thermoplastic resin is 95wt% or more and thermosetting resin is
Base resins with a blending ratio of 5wt% or less tend to undergo flow deformation during sintering, and thermoplastic resins
A base resin having a blending ratio of 50 wt% or less and a thermoplastic resin of 50 wt% or more is not preferable because the mechanical strength of the bearing decreases. The mixing ratio of the thermoplastic resin and thermosetting resin described above was confirmed from the results of the following test on the radial crushing strength constant of a porous sintered synthetic resin bearing. That is, polyphenylene sulfide resin powder is used as the thermoplastic resin, polyimide resin powder is used as the thermosetting resin, and the mixing ratio of the thermoplastic resin and the thermosetting resin (thermoplastic resin/thermosetting resin) is 100. :0 (weight ratio) to 5 weight ratios 45:55
After filling the base resin into a mold and molding at a molding pressure of 1300 kg/cm ² to obtain a cylindrical molded product, the molded product is sintered in a furnace as described below. A cylindrical synthetic resin porous sintered bearing (bush) was obtained by heating and sintering under the following conditions. The sintered bearing thus obtained was compressed in the radial direction and the radial crushing strength constant was measured, and the results are shown in FIG. Generally, it is preferable for a synthetic resin porous sintered bearing to have a radial crushing strength constant of 4 Kg/ ^cm2 or more, and from this experimental result, the mixing ratio of thermoplastic resin/thermosetting resin is 95-50:5-50 ( weight ratio), preferably
A suitable weight ratio is 90-70:10-30. The solid lubricant blended into the base resin is mixed to improve bearing performance, especially dry lubricity, and includes fluororesin, graphite, molybdenum disulfide, and soft metal powders such as lead and indium. is used. One or more of these solid lubricants can be selected and used, and the mixing ratio of the solid lubricant is 5 parts by weight per 100 parts by weight of the base resin.
~30 parts by weight is suitable. If the mixing ratio of the solid lubricant is less than 5 parts by weight, no improvement in bearing performance will be observed, and if it is more than 30 parts by weight, the mechanical strength of the sintered product will be reduced. The reinforcing material blended into the base resin is mixed for the purpose of improving the heat deformability, thermal conductivity, surface hardness, mechanical properties, etc. of the base resin, and includes glass fiber, carbon fiber, titanate cauliver, etc. Fibrous substances, metal powders made of copper, tin, zinc or their alloys, metal oxides such as titanium oxide and zinc oxide, and inorganic materials such as barium sulfate, calcium carbonate, silica, mica, talc, and clay are used. Ru. One or more of these reinforcing materials can be selected and used, and the appropriate blending ratio of the reinforcing materials is 10 to 50 parts by weight per 100 parts by weight of the base resin. If the proportion of the reinforcing material is less than 10 parts by weight, no reinforcing effect will be observed, and if it is more than 50 parts by weight, the strength will be improved, but bearing performance will deteriorate. Furthermore, both the solid lubricant and reinforcing material described above can be blended into the base resin. In this case, the blending ratio in the base resin is preferably such that the total amount of the two does not exceed 15 to 70 parts by weight per 100 parts by weight of the base resin. If the total amount of both is less than 15 parts by weight, no improvement in bearing performance or reinforcing effect will be observed, and if it is more than 70 parts by weight, there will be problems such as deterioration of bearing performance and making the sintered product brittle. The appropriate composition range of the solid lubricant and/or reinforcing material blended into the above-mentioned base resin was confirmed by the following test. (Sample) A base resin was formed using 90 wt% polyphenylene sulfide resin powder as a thermoplastic resin and 10 wt% polyimide resin as a thermosetting resin.
After forming a mixture by mixing 3 to 35 parts by weight of fluororesin powder as a solid lubricant and 3 to 35 parts by weight of copper powder as a reinforcing material to 100 parts by weight of the base resin, the mixture is placed in a mold. Filling and molding pressure
Molded with 1300Kg/cm ² to make a cylindrical molded product (butsu)
I got it. This cylindrical molded product was then heated and sintered to obtain a synthetic resin porous sintered bearing, which was then subjected to oil impregnation treatment. The synthetic resin porous sintered bearing thus obtained was tested for load resistance and radial crushing strength constant. The results are shown in the table below. The test conditions for the load-bearing test are as follows. (Test conditions) Speed: 10m/min Load: Cumulative load of 10Kg/ ^cm2 every 10 minutes Compatible material: Carbon steel for mechanical structure (S45C) Test method: Thrust test In the table, the symbol A refers to the base resin The mixing ratio (parts by weight) of the solid lubricant with respect to 100 parts by weight, and the symbol B represents the mixing ratio (parts by weight) of the reinforcing material with respect to 100 parts by weight of the base resin.

【table】

〔Example〕

Examples of the present invention will be described below. <Example> 90 wt% polyphenylene sulfide resin powder (manufactured by Philips Corporation, product name: Ryton P-4) with a mesh under of 100 as a thermoplastic resin and polyimide resin powder with a mesh under of 350 as a thermosetting resin ( A base resin (mixed powder) was obtained by mixing 10 wt% of Kerimide 601 (manufactured by Rhone-Poulenc). This base resin is filled into the mold,
Molding pressure 700Kg/cm ² , 900Kg/cm ² , 1100Kg/cm ² ,
1300Kg/cm ² , 1300Kg/cm ² , 1500Kg/cm ² , 1700Kg/
cm ² to obtain a molded product with an inner diameter of 20 mm, an outer diameter of 25.6 mm, and a length of 20 mm. The molded product obtained in this way is placed in a heating furnace, the temperature is raised from room temperature (25°C) at a rate of 3°C/min for about 16 minutes, and the operation is then held at that temperature for about 15 minutes, which is repeated. After increasing the temperature cumulatively in stages to 330°C, it was cooled to room temperature in the furnace and taken out from the furnace to obtain a synthetic resin porous sintered bearing. Then, apply SAE#30 as a lubricant to the sintered bearing.
Vacuum impregnated with engine oil. FIG. 1 shows the results of measuring the dimensional change (based on mold dimensions), lubricant impregnation rate, and compressive strength of the synthetic resin porous sintered bearing thus obtained with respect to molding pressure. Furthermore, FIG. 2 shows the results of testing the bearing performance (load resistance) of a synthetic resin porous sintered bearing obtained by molding and sintering at a molding pressure of 1300 kg/cm ² . The test conditions were the same as those described above. In FIG. 2, the graph marked with x shows the results of a similar test conducted on a conventional porous sintered polyamide resin bearing. As is clear from these test results, when combining the results of dimensional change, impregnation rate, and compressive strength, the appropriate molding pressure is 900 to 1600 Kg/ ^cm2 .
In addition, the load capacity as a bearing performance was 100Kg/cm ² or more (the test was stopped at 100Kg/cm ² due to the capacity of the testing machine). <Example> The thermoplastic resin and thermosetting resin used in the example were used as the base resin, and fluororesin (manufactured by Mitsui Fluorochemical Co., Ltd., product name: Teflon 7AJ) was used as a solid lubricant for 100 parts by weight of the base resin. A mixed powder was obtained by mixing 10 parts by weight. The mixed powder was filled into a mold and molded at a molding pressure of 1300 kg/cm ² to obtain a molded product. Next, this molded product was sintered under the same conditions as in the previous example to obtain a synthetic resin porous sintered bearing, and then impregnated in the same manner as in the example. The lubricant impregnation rate of this synthetic resin porous sintered bearing was 13 vol%. The load bearing performance of the porous sintered synthetic resin bearing was examined. The test results are shown in Figure 2. The test results show that the synthetic resin porous sintered bearings obtained in Examples tend to have a slightly lower coefficient of friction than the synthetic resin porous sintered bearings in Examples. This seems to be an effect of the fluororesin in the sintered bearing. <Example> A base resin having the same composition as the base resin used in the above example was prepared, and copper powder (manufactured by Fukuda Metal Foil & Powder Industries Co., Ltd., CE-15) was added as a reinforcing material to 100 parts by weight of the base resin. ) and 15 parts by weight of zinc oxide powder (manufactured by Kanto Chemical Co., Ltd.) were mixed to obtain a mixed powder. This mixed powder was molded and sintered under the same molding and sintering conditions as in the previous example to obtain a synthetic resin porous sintered bearing, which was then subjected to an impregnation treatment. The lubricant impregnation rate of this product was 12.4 vol%. Next, we conducted a load-bearing test on this synthetic resin porous sintered bearing and found that the load-bearing capacity was 100Kg/cm ²
As described above, the friction coefficient was in the range of 0.09 to 0.12, and the performance was almost the same as that of the synthetic resin porous sintered bearing of the example, but the friction surface was better than that of the bearing of the example. <Example> A base resin having the same component composition as the base resin used in the above example was prepared, and fluororesin powder (same product as in the above example) was added as a solid lubricant to 100 parts by weight of the base resin. A mixed powder was obtained by mixing 25 parts by weight of copper powder (same product as in the above example) and 20 parts by weight of zinc oxide powder (same product as in the above example) as a reinforcing material. This mixed powder was molded and sintered under the same molding and sintering conditions as in the previous example to obtain a synthetic resin porous sintered bearing.
Impregnation treatment was performed. The lubricant impregnation rate of this product is
It was 12.5vol%. Then, a load test was conducted on the porous sintered synthetic resin bearing. The results are shown in FIG. The test results showed that this synthetic resin porous sintered bearing had a lower coefficient of friction and a better friction surface than the bearings of the above examples. <Example> 90wt% of paraoxybenzoyl resin powder (manufactured by Nippon Econol Co., Ltd., trade name: ECONOL E100) with a mesh under 100 as a thermoplastic resin and polyimide resin powder with a mesh under 350 as a thermosetting resin (as in the above example) The same product) was used as a base resin, and for 100 parts by weight of the base resin, 15 parts by weight of fluororesin powder (same product as in the above example) was used as a solid lubricant, and copper powder (same as in the above example) was used as a reinforcing material. A mixed powder was obtained by mixing 25 parts by weight of zinc oxide powder (product) and 20 parts by weight of zinc oxide powder (same product as in the above example). This mixed powder was molded and sintered under the same molding and sintering conditions as in the previous example to obtain a synthetic resin porous sintered bearing, which was then subjected to an impregnation treatment. The lubricant impregnation rate of this product was 12.8 vol%. Then, a load test was conducted on the porous sintered synthetic resin bearing. As a result, the load capacity is 100
Kg/cm ² or more and a friction coefficient in the range of 0.06 to 0.08, which showed performance equivalent to that of the synthetic resin porous sintered bearing of the above example. <Example> 90 wt% polyethersulfone resin powder (manufactured by ICI, UK, product name: VICTREX200P) with a mesh under of 100 as a thermoplastic resin and polyimide resin powder with a mesh under of 350 as a thermosetting resin (the above example) (same product as in the above example) 10 wt% as a base resin, and fluororesin powder as a solid lubricant (same product as in the above example) for 100 parts by weight of the base resin.
A mixed powder was obtained by mixing 10 parts by weight. This mixed powder was filled into a mold and molded at a molding pressure of 1300 kg/cm ² to obtain a molded product.
After increasing the temperature from room temperature for about 16 minutes at a rate of 3℃/min, the temperature is held at that temperature for about 15 minutes, which is repeated to cumulatively increase the temperature step by step. The synthetic resin is heated to 270℃ and sintered. A porous sintered bearing was obtained. This sintered bearing was subjected to impregnation treatment in the same manner as in the previous example. The lubricant impregnation rate of this product was 12.4 vol%. Next, we conducted a load-bearing test on this synthetic resin porous sintered bearing, and found that the load-bearing capacity was 100Kg/cm ² .
The friction coefficient showed a range of 0.05-0.08. <Example> As a thermoplastic resin, 100 mesh under polyether sulfone resin powder (same product as in the above example) 45 wt% and 100 mesh under polysulfone resin powder (manufactured by Nissan Chemical Industries, Ltd., product name: Udel) were used. The base resin is 45 wt% of polysulfon P-1700) and 10 wt% of 350 mesh under polyimide resin powder (same product as in the above example) as a thermosetting resin, and a solid lubricant is added to 100 parts by weight of the base resin. Then, 10 parts by weight of fluororesin powder (the same product as in the above example) was mixed to obtain a mixture. This mixture was filled into a mold and molded at a molding pressure of 1300 kg/cm ² to obtain a molded product.Then, the temperature was raised from room temperature for about 16 minutes at a rate of 3°C/min as in the example. After that, the temperature was repeatedly held at the temperature for about 15 minutes, and the temperature was raised cumulatively to 250°C,
A synthetic resin porous sintered bearing was obtained by sintering. The sintered bearing thus obtained was subjected to the same impregnation treatment as in the example. The lubricant impregnation rate of this product is
It was 12.3vol%. Next, we conducted a load-bearing test on this synthetic resin porous sintered bearing, and the results showed that the load-bearing capacity was 100 kg/ ^cm2 or more, and the coefficient of friction was 0.07 to 0.09.
The range of [Effects] The present invention having the above-described configuration has the following effects. A porous sintered synthetic resin made by molding, heating and sintering a base resin consisting of a thermoplastic resin and a thermosetting resin with excellent heat resistance, or a mixture of the base resin and a certain proportion of a solid lubricant and/or reinforcing material. Since the bearing is a porous material, it has a high lubricant impregnation rate and has excellent bearing performance, that is, high speed, load capacity, and low friction, and has excellent mechanical strength and heat resistance. It can be used in high temperature atmosphere. Manufacturing is simple because a molded product molded at room temperature is sintered under conditions of cumulative temperature rise. A synthetic resin porous sintered bearing with little dimensional change can be obtained.

[Brief explanation of drawings]

Fig. 1 is a graph showing the relationship between molding pressure, dimensional change, lubricant impregnation rate, and compressive strength of a synthetic resin porous sintered bearing obtained by the manufacturing method of the present invention;
The figure is a graph showing the load resistance test results of a synthetic resin porous sintered bearing obtained by the manufacturing method of the present invention and a conventional product. Figure 3 is a graph showing the synthetic resin porous sintered bearing obtained by the manufacturing method of the present invention. 2 is a graph showing the results of measuring the radial crushing strength constant when the blending ratio of thermoplastic resin and thermosetting resin was changed.

Claims (1)

[Claims] 1. 50 to 95 wt% of one or more thermoplastic resins selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, and polyethersulfone resin, and 5 to 95 wt% of thermosetting resin. 50wt% to form a base resin, and after filling the base resin into a mold, the molding pressure is 900 ~
A molded product is formed by molding at 1600Kg/cm ² , and then the molded product is heated to a melting point of the thermoplastic resin of 0 to 50°C in a furnace.
1. A method for producing a porous sintered synthetic resin bearing, which comprises heating and sintering the bearing under conditions of continuous or stepwise cumulative temperature increase of 1 to 8° C./min to a temperature exceeding 1° C./min. 2 50 to 95 wt% of one or more thermoplastic resins selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, polyether sulfone resin and 5 to 50 wt% of thermosetting resin are mixed. After forming a base resin and mixing 100 parts by weight of the base resin with 5 to 30 parts by weight of a solid lubricant to obtain a mixed powder, the mixed powder was filled into a mold and the molding pressure was 900 to 1600 kg/cm. ² to form a molded product, and then the molded product is continuously or stepwise cumulatively heated at 1 to 8°C/min to a temperature exceeding the melting point of the thermoplastic resin by 0 to 50°C in a furnace. A method for producing a porous sintered synthetic resin bearing characterized by heating and sintering it under certain conditions. 3 50 to 95 wt% of one or more thermoplastic resins selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, and polyethersulfone resin and 5 to 50 wt% of thermosetting resin are mixed. After forming a base resin and mixing 10 to 50 parts by weight of a reinforcing material to 100 parts by weight of the base resin to obtain a mixed powder, the mixed powder is filled into a mold and a molding pressure of 900 to 1600 Kg/cm ² is obtained. to form a molded product, and then heat the molded product in a furnace to a temperature of 0 to 50°C higher than the melting point of the thermoplastic resin.
A method for producing a porous sintered synthetic resin bearing characterized by heating and sintering under conditions of continuous or stepwise cumulative temperature increase at ℃/min. 4 50 to 95 wt% of one or more thermoplastic resins selected from polyphenylene sulfide resin, paraoxybenzoyl resin, polysulfone resin, and polyethersulfone resin and 5 to 50 wt% of thermosetting resin are mixed. A base resin is formed, and 100 parts by weight of the base resin is mixed with 5 to 30 parts by weight of a solid lubricant and 10 to 50 parts by weight of a reinforcing material in such a range that the total amount of both does not exceed 70 parts by weight to form a mixed powder. After obtaining, the mixed powder is filled into a mold and the molding pressure is 900 to 1600.
Kg/cm ² to form a molded product, and then the molded product is heated in a furnace to a temperature that exceeds the melting point of the thermoplastic resin by 0 to 50°C, with continuous or stepwise cumulative heating of 1 to 8°C/min. A method for producing a porous sintered synthetic resin bearing characterized by heating and sintering it under warm conditions.