Pump impeller improvement
AssigneeBorg-Warner Corporation
InventorLawrence G. Eagle
Life of this patent
Estimating the term…
Abstract
To retain thrust washers and to prevent them from spinning or rotating at speeds less than the pump impeller with which they are associated, the thrust washers are slotted or split. The slotted or split washers expand due to centrifugal force and due to the difference in velocity across the face of the washer when the impeller spins; expansion of the thrust washer causes a braking force against the retaining ring on the impeller, so that the washer rotates with and at the same speed as the impeller.
Claims3
In combination with a rotatable element mounted on an axially extending shaft and having an axially open-ended annular cavity defined in part by a substantially circular and axially extending outside rim, and a fixed member arranged adjacent to said rotatable element in junxtaposition to said cavity;
- a generally annular thrust washer with a radial split and separation therethrough so as to be substantially C-shaped in plan view positioned in said cavity to be retained by said rim and being rotatable with said rotatable element;
- said thrust washer also being in junxtaposition to and contacting said fixed member;
- said thrust washer expanding radially upon rotation of said rotatable element due to centrifugal force exerted thereon and thus exerting a retaining force on said rim which retains said washer in said cavity and insures the rotation thereof at substantially the same speed as that of said rotatable elements.
In combination with a rotatable pump impeller mounted on an axially extending shaft and rotatable with said shaft,
- said impeller having an axially open-ended annular cavity defined in part by a substantially circular and axially extending outside rim;
- and a fixed diffuser member arranged adjacent to said rotatable impeller in junxtaposition to said cavity,
- a generally annular thrust washer with a radial split and separation therethrough so as to be substantially C-shaped in plan view positioned in said catity to be retained by said rim and being rotatable with said rotatable impeller;
- said thrust washer also being in juxtaposition to and contacting said diffuser;
- said thrust washer expending radially upon rotation of said rotatable impeller due to centrifugal force exerted thereon and thus exerting a retaining force on said rim which retains said washer in said cavity and insures the rotation thereof at substantially the same speed as that of said rotatable pump impeller.
In a multi-stage pump having a plurality of rotatable impellers mounted on an axially extending shaft for rotation therewith, and a plurality of stationary diffusers intermediate the impellers each of which is in juxtapositioned to at least one impeller,
- at least one axially open-ended annular cavity on each said impellers defined in part by an outside, substantially circular and axially extending rim, each cavity being closely adjacent to an adjacent diffuser;
- the improvement comprising;
- a generally annular thrust washer with a radial split and separation therethrough so as to be substantially C-shaped in plan view positioned in each said cavity to be retained by said rim and being rotatable with said rotatable impeller and in contact with the adjacent diffuser;
- each said thrust washer expanding radially upon rotation of said impellers due to centrifugal force exerted thereon and thus exerting a retaining force on said rim which retains each said washer in its cavity and insures the rotation thereof of substantially the same speed as that of said impellers.
Dependencies are inferred from the claim text.