Rotary kinetic fluid motors or pumps – With lubricating – sealing – packing or bearing means having... – For shaft sealing – packing – lubricating or bearing means
Reexamination Certificate
2000-04-25
2001-12-11
Verdier, Christopher (Department: 3745)
Rotary kinetic fluid motors or pumps
With lubricating, sealing, packing or bearing means having...
For shaft sealing, packing, lubricating or bearing means
C415S111000, C415S141000, C415S174200, C415S174300, C277S370000, C277S376000, C277S390000, C277S423000
Reexamination Certificate
active
06328528
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention generally relates to pumps with impellers and in particular to an elastomeric water pump impeller used in appliances.
Dishwashers and washing machines use water pumps with impellers to move liquid through and out of the appliance in a series of wash, rinse, and drain cycles. Such pumps include a housing, a rigid cover, an elastomeric impeller molded around a rigid impeller insert for slip fitting onto a rotatable drive shaft or motor shaft, a mechanical face seal consisting of a seal head assembly and a seal seat for preventing liquid leakage between the fixed housing and the rotating impeller, and a two-piece thrust bearing, one half mounted in the impeller for running against the other half mounted in the rigid cover. This thrust bearing resists the axial force of the mechanical face seal and also establishes the axial running clearances of the impeller with both the housing and the rigid cover as well as determining the axial operating height of the mechanical face seal assembly.
Conventional water pumps rely on a controlled cross-sectional squeeze of a fixed integral elastomeric radial rind molded into the inner diameter of the rigid impeller insert to provide retaining, static sealing, and positive rotational drive functions between the inner diameter of the impeller insert and the seal seat outer diameter. Additionally, this cross-sectional squeeze requirement is very precise which often necessitates centerless grinding of the seal seat's outer diameter. However, this system is complex and costly. Thus, there is a need for a simpler, more cost effective and reliable water pump for appliances that is easier to fabricate and faster to assemble.
SUMMARY OF THE INVENTION
The present invention provides an impeller with a seal seat retainer for a water pump having a rigid insert. The elastomeric impeller is attached to the rigid insert which has a tubular extension. The elastomeric impeller has a radial elastomeric retaining lip on its inner diameter and a portion forming a receiving cavity between the lip and the tubular extension. The seal seat is disposed in the receiving cavity. The elastomeric lip is stretched radially to permit receiving the seal seat in the receiving cavity and subsequently, as the lip contracts radially to its original condition, the lip grips the seal seat in the receiving cavity. This results in a simpler, more cost effective water pump impeller and seal seat assembly.
The object of the present invention is to provide a water pump with an elastomeric impeller with an integral, axially extending and radial retaining elastomeric lip which initially stretches radially outward to receive a seal seat with a wide range of outer diameter tolerances therein and which subsequently attempts to return to an unstretched condition, providing a compressive force on the outer diameter of the seal seat to hold it in a receiving cavity with respect to the impeller.
Another object of the present invention is to provide a radial retaining lip to capture the seal seat outer diameter during assembly and to provide for a static sealing shoulder between the seal seat and the rigid insert of the elastomeric impeller.
Still another object is to provide an elastomeric impeller with a rigid insert that includes flats located on an outer diameter of the rigid insert to engage flats located on the inside diameter of the seal seat in order to provide a positive rotational drive member between the impeller and the seal seat.
A still further object of the invention is to provide an elastomeric bladed pump impeller with a positive drive to the seal seat and which optionally can be provided with a formed open channel in the axially extending and radial retaining elastomeric lip to permit detection of any leakage between the integral elastomeric annular sealing shoulder surface and the rear surface of the seal seat.
Yet another object of the invention is to provide an elastomeric radial retaining lip on an inner diameter of the impeller which captures the seal seat therein and which forms a static seal between the seal seat outer diameter and an inner diameter of the impeller and which provides a secondary rotational drive with the seal seat.
These and other objects and features of the present invention will become apparent from the description and especially taken in conjunction with the accompanying drawings illustrating the invention and the preferred embodiment.
REFERENCES:
patent: 3663026 (1972-05-01), Mincuzzi
patent: 3846045 (1974-11-01), Mincuzzi
patent: 3914072 (1975-10-01), Rowley et al.
patent: 4411593 (1983-10-01), Taguchi
patent: 4502697 (1985-03-01), Heinl
patent: 4925366 (1990-05-01), Dorski
patent: 4944653 (1990-07-01), Wilkes
patent: 6062815 (2000-05-01), Holt et al.
patent: 6113106 (2000-09-01), Dahlheimer
patent: 3636165-C1 (1987-06-01), None
Freudenberg-NOK General Partnership
Kiczek Casimir R.
Tucker A. Michael
Verdier Christopher
LandOfFree
Elastomeric pump impeller does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Elastomeric pump impeller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Elastomeric pump impeller will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2562191