On an inner peripheral surface of a bearing hole into which a shaft is inserted, concave oil supply surfaces arranged dispersively like separated islands and a sliding surface continuous around the oil supply surfaces to hold an outer peripheral surface of the shaft are formed: a maximum height difference between the sliding surface and the oil supply surfaces is not less than 0.01% and not more than 0.5% of an inner diameter Di of the sliding surface; a surface aperture area ratio of pores at the sliding surface is not more than 10%; a surface aperture area ratio of pores at the oil supply surfaces is more than 10% and less than 40%; and an area of each of the oil supply surfaces is not less than 0.03 mm.sup.2 and not more than 0.2×Di.sup.2 (mm.sup.2).

A powder metallurgically produced, wear-resistant, and highly thermally conductive copper-based sintered alloy as matrix is disclosed. The sintered alloy includes a powder mixture of a copper-base powder, of a hard phase with a total share of 8 to 40% by weight, of a solid lubricant with a total share of 0.4 to 3.8% by weight, of a pressing additive with a total share of 0.3 to 1.5% by weight, and production-related impurities. The powder mixture includes at least 55% by weight of the copper-base powder.

A method and system for manufacturing a cast iron crankshaft for a vehicle are provided. The system comprises a molding unit arranged to form a negative sand cast mold of the cast iron crankshaft. The mold comprising at least one molded cavity having a pattern with dimensions of the cast iron crankshaft. The system further comprises a feeding mechanism comprising a riser having a connector through which molten metallic material flows to the cast mold. The feeding mechanism feeds the molten metallic material at a riser connection angle in the at least one mold cavity. The riser connection angle corresponds to a connector modulus. The connector modulus is 20% greater than a cast modulus. The riser geometry corresponds to a riser modulus. The riser modulus is 20% greater than the connector modulus. The system further comprises a furnace, a cooling area, a separation unit, a controller and a power source.

Linear motion mechanism sealants capable of operating at low torque when engaging in linear motion which are capable of carrying out sealing with respect to fine particulate several μm in diameter, and which are side seal units for sealing gaps at a shaft provided at a front end portion and a back end portion of a slider of a linear motion mechanism equipped with said shaft and said slider which carries out reciprocating linear motion on said shaft, the linear motion mechanism side seal units 4 being characterized in that fibrous surfaces of seal members comprising fibrous material are arranged so as to be directed toward said shaft in such fashion as to abut and conform to the cross-sectional shape of said shaft at the front end portion and the back end portion of the slider.

A sliding bearing may include an uncoated shaft and a bearing bush. The uncoated shaft may include a shaft material. The bearing bush may include a sintered bearing bush material. The shaft may be slidingly and moveably guided, relative to the bearing bush, within the bearing bush. The bearing bush material may have a residual porosity of 8 percent or more. A volume of the residual porosity may be filled with an oil up to 80 percent or more.

Provided is a bearing for a motor-type fuel injection pump. This bearing is composed of a Cu—Ni-based sintered alloy, inexpensive and has a superior corrosion resistance and abrasion resistance. The bearing contains 10 to 20% by mass of Ni, 2 to 4.5% by mass of Sn, 0.05 to 0.4% by mass of P, 2 to 7% by mass of C, and a remainder consisting of Cu and inevitable impurities. The bearing has a metal structure where Sn is uniformly dispersed and distributed in a metal matrix, and has a porosity of 7 to 17% where a free graphite is dispersed and distributed in pores.

An object of the present invention is to provide a rolling bearing which makes use of a porous rolling element and a selected kind of lubricant to impregnate with; is usable in various conditions; does not discharge foreign objects; and features low dust generation and long life. A rolling bearing includes an outer ring 2; an inner ring 1; and a plurality of rolling elements 3 assembled between mutually opposed outer ring track surface 2a and inner ring track surface 1a. The plurality of rolling elements 3 is provided by a combination of a porous rolling element 3a impregnated with a lubricant and a non-porous rolling element 3b.

An oil-impregnated sintered bearing comprises a bearing hole. In the bearing, sliding surfaces supporting an outer circumferential surface of a shaft and an oil supply surface whose diameter is larger than that of the sliding surfaces are formed on an inner circumferential surface of the bearing hole into which the shaft is inserted. The sliding surfaces and the oil supply surfaces are adjacent to each other in the axial direction of the bearing hole. A height gap “d1” between the sliding surfaces and the oil supply surface is not less than 0.01% and not more than 15% of an inner diameter of the sliding surfaces. A surface opening percentage of the sliding surfaces is not higher than 10%. A surface opening percentage of the oil supply surface is higher than 10%. An average circle-equivalent diameter of opening parts of pores on the sliding surfaces is not larger than 20 μm.

Systems and methods of making a cast steel alloy crankshaft for an internal combustion engine are provided. The method comprises providing a mold of the crankshaft. The mold has cavities to form the crankshaft. The method further comprises melting a first metallic material at between 1400 degrees Celsius (° C.) and 1600° C. to define a molten metallic material. In addition, the method further comprises feeding the molten metallic material at a riser connection angle of between 30° and 75° in the cavities of the negative sand cast mold. The method further comprises cooling the molten metallic material at a solidification time of between 5 seconds (sec) and 20 sec in the negative sand cast mold with at least one chill member to define a solidified metallic material having dimensions of the cast steel alloy crankshaft. Furthermore, the method comprises separating the solidified metallic material from the negative sand cast mold to define the cast steel alloy crankshaft.

A sliding bearing may include an uncoated shaft and a bearing bush. The uncoated shaft may include a shaft material. The bearing bush may include a sintered bearing bush material. The shaft may be slidingly and moveably guided, relative to the bearing bush, within the bearing bush. The bearing bush material may have a residual porosity of 8 percent or more. A volume of the residual porosity may be filled with an oil up to 80 percent or more.