Title of Invention

"A PUMPING DEVICE FOR LUBRICATION OF A BEARING SUMP"

Abstract A pumping device for lubrication of a bearing sump, said device comprising: a cup-like rotatable member (30) defining a substantially vertical axis, and having longitudinally directed oppositely handed helical grooves (33, 36) on inner and outer surfaces thereof: a smooth walled bore (39) in a stationary member closely surrounding without contacting the inner surface of said cup-like rotatable member (30); and a smooth-walled stationary cylindrical member (31) closely surrounded without contact by the outer surface of said cup-like member (30); such that rotation of said cup like member (30) causes the fluid to be pumped upwardly on one said surface and downwardly on the other said surface of the cup-like member (30) in order to lubricate a sump (40) to a level sufficient to cover a lower portion of said rotatable cup-like member (30), said smooth-walled bore (39), and said smooth-walled cylindrical member (31).
Full Text The present invention relates to a pumping device for lubrication of a bearing sump.
This invention relates generally to lubrication of bearings on a rotatable shaft and more particularly to supplying a lubricating fluid to bearings, within a vertical wet-sump bearing housing, at a constant flow rata which is independent of operating spaed.
Present bearing lubrication systems for vertical wet sump bearing housings are typically designed to supply lubricant at a flow rate specific to a design operating speed. They pump lubricant from a sump at the bottom of the housing to bearings at the top of the housing. The lubricant flows down through the bearings and returns to the sump. The amount and flow rate of lubricant supplied to the bearings is limited by the operating speed of the pump mechanism, the viscosity of the lubricant, and the size of the passages through which the lubricant is pumped to the bearings. While such systems, assuming constant viscosity, perform adequately at the design speed, they may become ineffective at low operating speed, or thsy may provide excess lubricant at high operating speed, as would be encountered with a variable speed drive input. Thus, at low speed lubrication may be inadequate, while at high speed excessive lubricant flow may cause over pressure which leads to seal failure and leakage of lubricant to the surroundings.
In addition, lubricants are viscous liquids which are subject to viscosity changes which are inversely related to temperature variations. Thus temperature increases cause viscosity decreases, and. temperature decreases causa viscosity increases. Even when operating at design speed, the lubricant becomes hot due to mechanical heat generation and loses viscosity. This causes decreased pumping action and results in inadequate lubrication of the bearings.Such inadequacies result in costly damage to equipment and the environment.
GB-A-444 496 discloses an apparatus for lubricating bearings in accordance with the preamble of claim 1.
According to one aspect of the present invention, thora is provided an apparatus for lubricating bearings on a vertical rotatable shaft within a bearing housing, comprising a lower lubricant sump at a lower portion of, said bearing housing; an upper lubricant reservoir at an upper portion of said bearing housing; a conduit providing fluid communication between eaid lower- lubricant sump and said upper lubricant reservoir; means for metering a flow of lubricant from said upper lubricant reservoir into upper bearings; means for pumping lubricant from said lower lubricant sump, through aaid conduit, to said upper lubricant reservoir at a rate exceeding a rate of said metered flow into said upper bearings; and means in said upper lubricant reservoir, for maintaining a constant head of lubricant above said metering means and for shunting excess lubricant back to aaid lower lubricant sump; characterised by means for feeding a portion of said excess lubricant to said lower bearings before said excess lubricant is returned to said lower lubricant sump.
According to another aspect of the present invention, there is provided a pumping device comprising a cup-like rotatable member, with an axis that is, in use, vertical, and having longitudinally directed oppositely handed helical grooves on inner and outer surfaces; a smooth-walled bore in a stationary member closely surrounding without contacting the outer surface of said cup-like rotatable member; a smooth-walled stationary cylindrical member closely surrounded without contact by the inner surface of said cup-like member; and a sump which contains fluid at a level sufficient to cover a lower portion of said rotatable cup-like member, said smooth-walled bore, and said smooth-wallad cylindrical member, such that rotation of said cup-lika member causes the fluid to be pumped upwardly on one said surface and downwardly on the other said surface of the-cup-like member.
Accordingly, the present invention relates to a pumping device for lubrication of a bearing sump, said device comprising:
a cup-like rotatable member (30) defining a substantially vertical axis, and having longitudinally directed oppositely handed helical grooves (33, 36) on inner and outer surfaces thereof:
a smooth walled bore (39) in a stationary member closely surrounding without contacting the inner surface of said cup-like rotatable member (30); and
a smooth-walled stationary cylindrical member (31) closely surrounded without contact by the outer surface of said cup-like member (30); such that rotation of said cup like member (30) causes the fluid to be pumped upwardly on one said surface and downwardly on the other said surface of the cuplike member (30) in order to lubricate a sump (40) to a level sufficient to cover a lower portion of said rotatable cup-like member (30), said smooth-walled bore (39), and said smooth-walled cylindrical member (31).
Fig. 1 is a vertical schematic: partially sectional view of a pump equipped with a vertical wet sump lubrication system;
Fig. 2 is-a fragmentary bottom perspective view of the pumping device; and
Fig. 3 is a fragmentary, sectional elevation view of the lubricant metering and shunt features of an upper lubricant reservoir.
All the main features can be seen by referring to Pig. 1; however, it is also helpful to rafer to Figs. 2 and 3, as appropriate, to further appreciate details of pumping, metering and shunting provisions. In Fig. 1, the invention is shown aa applied to a vertical pump unit 60. A bearing housing assembly 50 has upper bearings 14 and lower bearings 18 supporting a. rotatable shafts which is mounted within a bearing housing 10. -A lower annular lubricant sump 4 0 in a lower end cover 11 of the housing 10 and an upper, annular lubricant reservoir 2 0 in an upper end cover 12 are connected by a conduit 35, which is preferably bored in the wall of the housing 10. A cup-like pumping or lifting device 30, which is fixsd to the rotatable shaft 5, pumps lubricant by means of at least one helical groove 33 in the outer surface thereof, which groove co-operates with the inner wall 31 of a bore through whiah the cup-like pumping device 30 extends downward into the lower lubricant sump 40. Note that there is no contact between the cup-like pumping device 30 and the inner wall 31 of the bore. The groove 33 is sized" such that it pumps an excess quantity of lubricant to the upper bearings 14 at all operating speeds. These features are seen in Pigs. 1 and 2 .
The upper lubricant reservoir 20, seen in Figs. 1 and 3, has a spillway or overflow .barrier 26 which maintains a constant pressure head above a metering orifice 25, The metering orifice 25 is sized to provide full lubrication, as required by the upper bearings 14, at all operating speeds and viscosity ranges. The metering orifice 25 has its mouth located slightly above the bottom of the upper reservoir 20 to retain a small amount of lubricant in the reservoir 20 upon shut-down. This assures a minimal response time for supplying JLubrioant to the upper bearings 14 when re-starting the unit after such shut-down. Any excess lubricant reaching upper reservoir 20 passes over the overflow barrier 26 and is shunted back to the lower sump 40 through shunt passage 19. This overflow and shunt feature allows fchs .pumping device to operate with no throttling or other constriction without regard to operating speed; because the full lubricant requirements are always met/ and any excess lubricant is merely returned. to the lower sump 40. A portion o.f the excess lubricant is directed, by the bowl (Shaped lower surface of the housing 10, through the lower bearings 18 before draining to the lower sump 40.
Lubricant which passes through the upper bearings 14 falls onto a alinger ring 4'5 attached to the shaft 5 below the bearings 14. The alingar ring 45 throws the lubricant against the wall of the bearing housing 10 where it gives up heat collected by contacting various parts of the

bearings and shaft 5. By design, lubricant which is not actually lubricating the bearings is exposed as much as possible to cooler surfaces within the bearing housing 10, This helps to dissipate heat and to maintain a steady state operating temperature.
The cup-like pumping device 30 also acts aa a heat sink to extract hsat from the shaft 5 adjacent to the lower bearing 18. The intimate mixing- contact between, the lubricant and the pumping device 30 assures maximum heat transfer to the lubricant, which then serves to carry the heat to the housing walls 1Q, 11, 12 and to thus dissipate it to the surroundings of the hotising assembly 50. This feature is important especially if the shaft 5 is exposed to an external heat source such as hot pumpage or hot air. Thus, under any operating conditions, the bearing housing assembly 50 quickly achieves a steady-state operating temperature.
A seal is provided to prevent escape of lubricant from the lower sump 40. This is accomplished without contact between stationary and rotating parts. The lower sump 40 has an inner wall 39 which extends above the top of. the stationary lubricant level and, without contacting it, surrounds the shaft 5 and effectively provides a static seal. No further sealing would be needed except for induced turbulence in the lubricant within the lower sump 40. To counteract turbulence induced lubricant loss, a non-contacting dynamic axial counterflow sealing device is provided using the cup-lika pumping device 30, A helical groove 36 on the inner surface of the pumping device 39, having an opposite handing from the pumping grove 33, pumps Itibricant downward during operation. The groove 36 cooperates with the oxitar surface of... tha inner wall 30 without contact, in the same manner as groove 33 cooperates with wall 31 of the bore without contact.

The bearing lubrication system has been, shown, in Fig. 1 as applied to a pump. It is clear that any vertical bearing housing which is lubricated by a wet sump lubrication system can benefit from the features disclosed here.





WE CLAIM:
1. A pumping device for lubrication of a bearing sump, said device comprising:
a cup-like rotatable member (30) defining a substantially vertical axis, and having longitudinally directed oppositely handed helical grooves (33, 36) on inner and outer surfaces thereof:
a smooth walled bore (39) in a stationary member closely surrounding without contacting the inner surface of said cup-like rotatable member (30); and
a smooth-walled stationary cylindrical member (31) closely surrounded without contact by the outer surface of said cup-like member (30); such that rotation of said cup like member (30) causes the fluid to be pumped upwardly on one said surface and downwardly on the other said surface of the cup-like member (30) in order to lubricate a sump (40) to a level sufficient to cover a lower portion of said rotatable cup-like member (30), said smooth-walled bore (39), and said smooth-walled cylindrical member (31).
2. A pumping device as claimed in claim 1, wherein fluid is pumped upwardly on the outer surface of said cup-like member (30) and downwardly on the inner surface thereof.

Documents:

2110-DEL-2005-Abstract (15-01-2010).pdf

2110-del-2005-abstract.pdf

2110-del-2005-assignment.pdf

2110-DEL-2005-Claims (15-01-2010).pdf

2110-DEL-2005-Claims-(30-06-2011).pdf

2110-del-2005-claims.pdf

2110-DEL-2005-Correspondence Others-(30-06-2011).pdf

2110-DEL-2005-Correspondence-Others (15-01-2010).pdf

2110-del-2005-correspondence-others.pdf

2110-DEL-2005-Description (Complete) (15-01-2010).pdf

2110-del-2005-discription (complete).pdf

2110-DEL-2005-Drawings (15-01-2010).pdf

2110-del-2005-drawings.pdf

2110-DEL-2005-Form-1 (15-01-2010).pdf

2110-del-2005-form-1.pdf

2110-del-2005-form-18.pdf

2110-DEL-2005-Form-2 (15-01-2010).pdf

2110-del-2005-form-2.pdf

2110-DEL-2005-Form-3 (15-01-2010).pdf

2110-del-2005-form-3.pdf

2110-del-2005-form-5.pdf

2110-DEL-2005-GPA (15-01-2010).pdf

2110-del-2005-gpa.pdf

2110-DEL-2005-Petition-137 (15-01-2010).pdf


Patent Number 249145
Indian Patent Application Number 2110/DEL/2005
PG Journal Number 40/2011
Publication Date 07-Oct-2011
Grant Date 04-Oct-2011
Date of Filing 09-Aug-2005
Name of Patentee FLOWSERVE MANAGEMENT COMPANY
Applicant Address 222 W. LAS COLINAS BOULEVARD, SUITE 1500 IRVING, TEXAS 70539, U.S.A.
Inventors:
# Inventor's Name Inventor's Address
1 WILLIAM B. JONES, JR. 14963 LASHBURN STREET, WHITTIER, CA 90604
2 MARK L. HALL 13096 BLACKBURN STREET #175, GARDEN GROVE, CA 92843
3 VAHE HAYRAPETIAN 1535 THOMPSON AVENUE, GLENDALE, CA 91201
4 KHAJAK JACK MINASSIAN 1256 RUBERTA AVENUE, GLENDALE, CA 91201
PCT International Classification Number F04B 63/12
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 08/807,311 1997-02-27 U.S.A.