Lubricating systems for regenerative vacuum pumps

Abstract

In a vacuum pump of the regenerative type or including a regenerative section in which a rotatable substantially vertical shaft is supported by upper and lower bearings, a lubricating system for lubricating the bearings comprising an axial bore extending along the shaft and in communication with radial holes aligned respectively with the lower bearing and the upper bearing, the lower open end of the axial bore extending in to a shaft reservoir containing lubricating fluid, and in which the radial holes in alignment with the lower bearing are formed in a tapered surface of the axial bore.

1 . In a vacuum pump of the regenerative type or including a regenerative section in which a rotatable substantially vertical shaft is supported by upper and lower bearings, a lubricating system for lubricating the bearings comprising an axial bore extending along the shaft and in communication with radial holes aligned respectively with the lower bearing and the upper bearing, the lower open end of the axial bore extending in to a shaft reservoir containing the lubricating fluid, and in which the radial holes in alignment with the lower bearing are formed in a conically tapered surface of the axial bore.  
     
     
         2 . In a vacuum pump of the regenerative type or including a regenerative section in which a rotatable substantially vertical shaft is supported by upper and lower bearings, a lubricating system for lubricating the bearings comprising an axial bore extending along the shaft and in communication with radial holes aligned respectively with the lower bearing and the upper bearing, the lower open end of the axial bore extending in to a shaft reservoir containing lubricating fluid, and in which the radial holes in alignment with the lower bearing are formed in a conically tapered surface of the axial bore and the lower bearings.  
     
     
         3 . A bearing lubrication system in a vacuum pump comprising: 
 a shaft having a bore along a longitudinal axis of the shaft, wherein a first length of the bore has a constant diameter and a second length of the bore has a decreasing diameter;    an oil reservoir wherein the second length of the shaft is adapted to contact the oil reservoir;    a lower radial hole in the second length of the shaft, the lower radial hole forming a lower fluid passage between the bore and the lower bearing; and    an upper radial hole in the first length of the shaft, the upper radial hole forming an upper fluid passage between the bore and the upper bearing.    
     
     
         4 . The bearing lubrication system of  claim 3  wherein the vacuum pump comprises a rotor mounted on the shaft.  
     
     
         5 . The bearing lubrication system of  claim 3  wherein the vacuum pump comprises a motor.  
     
     
         6 . The bearing lubrication system of  claim 5  wherein the motor is adapted to simultaneously rotate the rotor and the shaft.  
     
     
         7 . The bearing lubrication system of  claim 3  wherein the vacuum pump is of a regenerative type.  
     
     
         8 . A bearing lubrication system in a vacuum pump comprising: 
 a shaft having a longitudinal axis and a bore, wherein the bore extends along a length of the shaft and forms a conical taper at a lower end of the shaft;    a motor for rotating the shaft about the longitudinal axis;    a plurality of upper bearings and a plurality of lower bearings wherein the upper bearings and the lower bearings support the shaft;    an oil reservoir, wherein the lower end of the shaft is adapted to contact the oil reservoir so that when the shaft rotates oil flows up through the bore;    a lower radial hole formed in the shaft and in the conical taper, wherein the lower radial hole is located proximate to at least one of the lower bearings; and    an upper radial hole formed in the shaft and the bore, wherein the upper radial hole is located proximate to at least one of the upper bearings.    
     
     
         9 . The bearing lubrication system as claimed in  claim 8  further comprising a rotor mounted on the shaft.  
     
     
         10 . The bearing lubrication system as claimed in  claim 9  further comprising a stator surrounding the rotor and the shaft.  
     
     
         11 . The bearing lubrication system as claimed in  claim 8  wherein the vacuum pump is of a regenerative type.  
     
     
         12 . A bearing lubrication system in a vacuum pump, the bearing lubrication system comprising: 
 a shaft comprising a bore having a constant diameter along a first length of the shaft and a decreasing diameter along a second length of the shaft;    an oil reservoir, wherein a portion of the second length of the shaft is adapted to contact the oil reservoir;    a plurality of lower bearings and a plurality of upper bearings wherein the lower bearings and the upper bearings support the shaft;    a plurality of lower radial holes in the shaft and the bore, wherein the lower radial holes are located proximate to the lower bearings; and a plurality of upper radial holes in the shaft and the bore, wherein the upper radial holes are located proximate to the upper bearings.    
     
     
         13 . The bearing lubrication system as claimed in  claim 12  wherein the vacuum pump comprises a motor for rotating the shaft about a longitudinal axis of the shaft.  
     
     
         14 . The bearing lubrication system as claimed in  claim 13  wherein the vacuum pump further comprises a rotor mounted on the shaft for rotation therewith.  
     
     
         15 . The vacuum pump as claimed in  claim 14  wherein the vacuum pump further comprises a stator surrounding the rotor and the shaft.  
     
     
         16 . The bearing lubrication system as claimed in  claim 14  wherein the vacuum pump is of a regenerative type.