Centrifugal oil pump flow proportioning and cooling system
AssigneeBeckman Instruments, Inc.
InventorRobert H. Giebeler, Jr.
Life of this patent
Estimating the term…
Abstract
A system for cooling and lubricating the drive motor of a centrifuge. The shaft of the motor includes an internal passage with an inlet having a size and taper sufficient to provide the desired rate of cooling oil flow through the motor. A lower bearing proportioning arrangement applies a high percentage of a small proportion of the total oil flow to the lower bearing. An upper bearing proportioning arrangement applies a low percentage of a large proportion of the total oil flow to the upper bearing. Together these features assure a high degree of motor cooling without overlubricating the bearings.
Claims21
In a lubricating and cooling system for a centrifuge motor of the type having a vertical shaft journalled in upper and lower bearings and an oil sump, said shaft defining an internal passage for the flow of oil from the sump and upper and lower holes through which oil on the surface of the passage may flow into the vicinity of the bearings, the improvement comprising:
- (a) a tapered inlet at the lower end of the shaft for forcing oil from the sump upwardly into the passage, the size and taper of said inlet being selected to produce through the passage a flow of oil that is substantially greater than that necessary to lubricate the bearings,
- (b) a lower nebulizing member for breaking a relatively high percentage of the oil emerging from the lower hole into a lubricating spray fine enough to enter the lower bearing,
- (c) an upper nebulizing member for breaking a relatively low percentage of the oil emerging from the upper hole into a lubricating spray fine enough to enter the upper bearing, and for permitting the remaining oil to return to the sump,
- (d) said passage including a radial step between the upper and lower holes, near the lower hole, for limiting the rate of oil flow through the lower hole to a small fraction of the total oil flow through the passage.
In a lubricating and cooling system for a centrifuge motor of the type having a vertical shaft journalled in upper and lower bearings and an oil sump, said shaft defining an internal passage for the flow of oil from the sump and upper and lower holes through which oil on the surface of the passage may flow into the vicinity of the bearings, the improvement comprising:
- (a) a tapered inlet at the lower end of the shaft for forcing oil from the sump upwardly into the passage, the size and taper of said inlet being selected to produce through the passage a flow of oil that is substantially greater than that necessary to lubricate the bearings,
- (b) lower proportioning means including a radial discontinuity in the passage for directing a first predetermined fraction of said flow of oil through the lower hole, and
- (c) upper proportioning means for diverting a predetermined fraction of the oil emerging from the upper hole into the vicinity of the upper bearing.
In a lubricating and cooling system for a centrifuge motor of the type having a vertical shaft journalled in upper and lower bearings and an oil sump, said shaft defining an internal passage for the flow of oil from the sump and upper and lower holes through which oil on the surface of the passage may flow into the vicinity of the bearings, the improvement comprising:
- (a) a tapered inlet at the lower end of the shaft for forcing oil from the sump upwardly into the passage,
- (b) a radial step for partitioning the surface of the passage into a lower surface region having a relatively small radius and an upper surface region having a relatively large radius, said step being located between the upper and lower holes,
- (c) a lower nebulizing member for receiving oil from the lower hole and for converting the same into a lubricating spray fine enough to enter the lower bearing,
- (d) an upper nebulizing member for receiving oil from the upper hole and for converting the same into a lubricating spray fine enough to enter the upper bearing, said upper nebulizing member including at least one gap through which oil may return to the sump without being converted into said spray,
- (e) whereby the upper and lower bearings are provided with predetermined respective proportions of the oil entering said inlet, and the shaft is provided with a flow of oil sufficient to prevent the same from overheating.
Dependencies are inferred from the claim text.