Showing papers by "Scott Bair published in 1981"
TL;DR: In this paper, the results of tribological studies carried out on hardened steel test bodies coated with solid lubricants are reported, which show that sputtered solid lubricant films are satisfactory for heavily loaded rolling contact applications as long as the slide-roll ratio is not very much larger than 0.02.
10 citations
01 Oct 1981
TL;DR: In this article, the authors present experimental evidence for the existence of three regimes of traction in concentrated contacts, i.e., mixed regime, asperity interaction, and high film thickness.
Abstract: Experimental evidence is presented for the existence of three regimes of traction in concentrated contacts. Data are obtained in a rolling contact simulator by varying the lubricant, temperature, rolling speed, load and surface roughness at a fixed slide-to-roll ratio. At lower thicknesses the mixed regime is encountered, and traction is increased due to asperity interaction, while at higher film thicknesses, the lubricant pressure is distributed over a greater area than the Hertzian region, resulting in a lower average pressure and reduced traction.
1 citations
01 Oct 1981
TL;DR: In this article, the authors presented experimental data on viscosity, elastic shear modulus, and limiting shear stress of 12 liquid lubricants, and they found that transition histories do affect the limiting stress of the materials in the form of isothermal compression resulting in a lower density and lower limiting stress than isobaric cooling.
Abstract: Experimental data are presented on viscosity, elastic shear modulus, and limiting shear stress of 12 liquid lubricants. It is shown that transition histories do affect the limiting shear stress of the materials in the form of isothermal compression resulting in a lower density and lower limiting stress than isobaric cooling. The measured limiting shear stress agrees with EHD traction data at slide-to-roll ratios of 0.1 or more. In pressure viscosity measurements of the polymer solutions, it is found that for some temperatures, the pressure viscosity coefficient of the blend is slightly less than that of the base, which results in the crossing of the viscosity-pressure isotherms at high pressures.
1 citations
Patent•
23 Jan 1981
TL;DR: In this paper, an upright suction carpet cleaner is provided with a solid rear axle having wheels mounted on either end thereof and a power assist transmission generally medially mounted therewith.
Abstract: An upright suction carpet cleaner is provided with a solid rear axle having wheels mounted on either end thereof and a power assist transmission generally medially mounted therewith. The transmission comprises a housing carrying an input pinion gear driven from the suction fan motor shaft in constant mesh with a pair of contra-rotating face gears freely rotatable upon the axle shaft. A pair of clutch assemblies selectively engage one or the other of the contra rotating face gears in timing relationship with the axle shaft, with the clutch assembly being selectively operable through a bowden cable connection to a shiftable hand grip on the cleaner handle so that slight forward pressure on the hand grip by an operator is effective to engage the forward clutch and provide power assist drive to the cleaner in a forward direction while a slight rearward pressure on the handle grip by the operator provided a power assist in reverse drive. Further, means are provided to lock the transmission in a neutral configuration when the handle is in an upright position.