Impeller for coolant pumps

Abstract

A cooling water pump for internal combustion engine includes a base and an outer cover forming a water input chamber, an impeller supported on a shaft within said chamber, fed shaft includes a bearing / seal unit mounted within the base and the shaft extended outwardly for connection to the engine. A one-piece, fully enclosed and double shrouded impeller is secured to the shaft. Impeller has a central hub with an outer peripheral concave surface, a bottom convex end wall, vanes are secured to the central portion of the concave wall in the bottom wall and project outwardly therefrom with an outer top shroud. The base has a recess within which the bearing / seal unit is mounted. The recess extends outwardly beyond the outer edge convex wall of the hub from a cooling chamber. The vanes direct a portion of the water flowing through the passageway into the recess for cooling purposes and then back into the radially outer portion of the passageway for discharge with the flowing water into the outlet passageway. The radially inner end of the shroud and outer convex wall overlap each other to form a controlled entrance into the outlet passageway to divert part of the flow into the recess.The invention pertains to a cooling water pump for an internal combustion engine. The pump has a base and a cover that form a water chamber. The chamber includes a one-piece, shrouded impeller secured to a drive shaft driven by the engine. The impeller has a central hub with vanes that project outwardly along with its integral shroud to form a flow passageway to a discharge opening. The base has a recess within which a bearing / seal unit is mounted. The recess extends outwardly beyond the hub to form a cooling passageway to the recess. A portion of the water flowing through the flow passageway is directed into the recess to cool the seal unit, and then back to the flow passageway for discharge. The shroud and hub can overlap to help control the flow to the recess.<?insert-end id="INS-S-00001" ?>

Description

BACKGROUND OF THE INVENTION[0001]This invention relates to a pump impeller for pumping a coolant and particularly for a water pump for cooling an internal combustion engine.[0002]Water pumps for internal combustion engines are well known and are present in the larger internal combustion engines. A widely used water pump generally includes an impeller mounted within a housing. The impeller includes a plurality of spaced vanes secured on a round base. The impeller is secured to a drive shaft and is rotatably mounted within the walls of a pump housing. The housing includes an outer closure wall and a shroud over the outer ends of the impeller vanes. A one-piece fully enclosed and double shrouded impeller has been disclosed. However, the system of manufacture is expensive and involves a complex procedure requiring a special high maintenance die unit with a timed and multiple pull action such as found in a camera shutter. An alternative common impeller is a two-piece assembly in which a ...

AI Technical Summary

Benefits of technology

[0005]The present invention provides a one-piece impeller design including an in-place molded shroud, which may be formed with known injection molding apparatus, thereby permitting a particularly cost-effective impeller. The molded impeller is readily constructed with a proper height and vane curvature to produce a specified flow, in combination with a shroud and flow control constructed to create proper cooling of a pump seal. The single piece impeller provides a more optimum flow of the coolant around the mechanical seat of the impeller. The result is a reduction in the operating temperature of the pump seals, with an increased operating life of the seal and the pump.

[0008]The impeller of the present invention is readily injection molded with well known injection molding equipment and with conventional plastic presently used in coolant pump impellers. The impeller of the present invention produces a highly cost-effective structure with both manufacturing and assembly costs, as well as an improved and long life pump assembly.

Problems solved by technology

However, the system of manufacture is expensive and involves a complex procedure requiring a special high maintenance die unit with a timed and multiple pull action such as found in a camera shutter.

In summary, the prior art plastic impellers involve costly manufacturing procedures which involve costly equipment and various procedures or the case of forming separate components with separate bonding of the separately bonded areas present areas of possible failure and should provide seal cooling means.

The present systems do not therefore provide a structure which permits the manufacture of a relatively simple structure for controlling the volume of water flow and efficient seal cooling.

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