Showing papers on "Fluid bearing published in 1979"

Radial and thrust-type hydrodynamic bearing capable of accommodating misalignment

Abstract: A hydrodynamic bearing capable of transmitting thrust and radial loads and able to accommodate angular misalignment between an inner load applying or supporting member rotatably connected to the bearing utilizes an outer cylindrical array of bearing pads disposed about a longitudinal axis, the pads having movable face portions with spherically curved bearing surfaces having a common center of curvature located on the longitudinal axis, the curved surfaces mating with a spherically curved periphery on the load supporting member. The face portions of the bearing pads are supported by curved laminated elastomer-inelastic material so that they are restricted to swinging motion about "swing points" located between the axis of rotation of the bearing and the face portions thereof under the combined influences of friction and load forces exerted thereagainst by the load applying or supporting member, so that wedge-shaped hydrodynamic gaps are created between the relatively moving bearing surfaces that are filled by the lubricant to maintain the surfaces apart while the motion is occurring through hydrodynamic action. Radial and thrust loads, as well as angular misalignment between the load supporting member and the bearing pads, are all accommodated by reason of the particular ball and socket relationship between the bearing members, without adversely affecting the hydrodynamic action of the bearing.

Precision spinning drop interfacial tensiometer

Abstract: An improved instrument for the precise measurement of interfacial tension between two fluid phases by means of a drop of the less dense fluid surrounded by the more dense fluid, both fluids spinning together in gyrostatic equilibrium. Elements of the invention eliminate departures from gyrostatic equilibrium which went unrecognized in the prior art. These elements are based on hydrodynamic principles unknown in the prior art. The instrument is characterized by the combined use of air bearings and sample-holder mountings which reduce vibrations and eccentricities, eliminate temperature gradients within the sample, and assure that interfering hydrodynamic flows are suppressed. Other improvements include biprecision sample tube, full visual access to the spinning drop, leveling provisions, timing belt transmission, avoidance of bearing heating and wear problems, and convenient control of sample temperature.

Steady State Performance of a Hydrodynamic Journal Bearing With a Pseudoplastic Lubricant

Abstract: Starting from the general shear stress-shear strain relation of the odd cubic polynomial type considering correlation effect for pseudoplastic (shear thinning) lubricant, a modified form of Reynolds’ equation (nonlinear) is derived under conventional hydrodynamic lubrication approximations. The finite difference technique with successive over relaxation is used adopting the solution of the associated linear equation as a first approximation to obtain the pressure distribution of a finite cylindrical journal bearing incorporating Reynolds’ boundary conditions. Steady state performance characteristics such as load capacity, attitude, friction and flow rate are obtained for various values of nonlinear parameter and bearing slenderness ratio. The results presented in nondimensional form are compared with established results for Newtonian lubricants. The investigation shows a significant effect of correlation on the bearing load capacity and flow rate.

Hydrostatic transmission lubrication

Abstract: A hydrostatic transmission having a pump and a motor of the radial piston type with each cylinder slipper bearing rotatably supported by a hybrid or combination hydrostatic and hydrodynamic bearing on an internal bearing. The hydrostatic bearing component has a restricted port connecting hydrostatic pressure fluid from the cylinder to supply a distribution recess in the slipper bearing surface for hydrostatic pressure feed of the fluid film providing hydrostatic balancing pressure gradient between the slipper and internal bearing to balance a high percentage of the hydrostatic pressure load and to meet flow requirements for low speed operation. The hydrodynamic bearing component has a low pressure source to spray fluid on the internal bearing, annular dams on each side retaining fluid on the internal bearing, and a taper at the leading edge of the slipper bearing to force fluid into the bearing clearance and provide a hydrodynamic balancing pressure component and fluid flow increasing with speed to balance the centrifugal load and effect balancing of the remaining hydrostatic load and to meet flow requirements which increase with speed. The total hydrostatic and hydrodynamic balancing pressure balances the total load.

Operating characteristics of a cantilever-mounted resilient-pad gas-lubricated thrust bearing

Abstract: A resilient-pad gas thrust bearing consisting of pads mounted on cantilever beams was tested to determine its operating characteristic. The bearing was run at a thrust load of 74 newtons to a speed of 17000 rpm. The pad film thickness and bearing friction torque were measured and compared with theory. The measured film thickness was less than that predicted by theory. The bearing friction torque was greater than that predicted by theory.

Hybrid type fluid bearing

Abstract: PURPOSE: To reduce the size and facilitate the processing of a hybrid fluid bearing by providing dynamic pressure generating grooves on the bearing surface and coating the bearing surface with a film of a material optionally selected except the surface of the grooves to allow the introduction of a pressure fluid through the grooves to form a static pressure bearing. CONSTITUTION: The bearing surface 11 and the other surfaces stopping the ejection of the pressure fluid are coated with a ceramic film. The surface of dynamic pressure generating grooves is not coated with the ceramic film. The depth of the grooves is the same with the thickness of the ceramic film. The fluid pressure generated by the grooves 2 as the bearing or a member placed opposite to the bearing is turned provides dynamic bearing effect and the external pressure fluid introduced through the grooves 2 provides static bearing effect, thus providing a single bearing with both dynamic and static bearing effects. COPYRIGHT: (C)1980,JPO&Japio

A radialltype* oil* air pressure* pumppmotor

Abstract: PURPOSE:To prevent a pressure fluid leakage from a fluid bearing in a piston by receiving the pushing force of the piston by the fluid bearing. CONSTITUTION:When piston 18 on the suction side of a pump tends to move away from slide bearing plate 12, ring-shaped plate 19 is pushed against slide bearing plate 12 by means of another piaton 18 on the discharge side of the pump, 10 so that ring-shaped plate 19 is prevented from moving away from slide bearing plate 12 all time. Thus, a fluid bearing is formed in the sliding surface between ring- shaped plate 19 and slide bearing plate 12. Rotor 3 is pushed against changeover valve plate 6 by the counter force of piston 18.