Foam encased pump

Abstract

A compact pump has a uni-body, or alternately a two-part, housing of self-skinning foam construction for superior noise and vibration reduction, such as needed for medical nebulizer applications. The uni-body foam housing is formed by molding the housing around a pump assembly having special features designed to shield and space apart moving or sensitive internal components of the pump assembly from the foam during the insert molding process. The alternate two-part foam housing is assembled using a union ring having multiple barbed pins that fit into openings in mating faces of the two housing sections.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims benefit to U.S. Provisional Patent Application No. 60 / 583,424, filed on Jun. 28, 2004.STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] Not applicable. BACKGROUND OF THE INVENTION [0003] The present invention relates to pumps and compressors and in particular to pumps and compressors with low noise characteristics, especially suited for use in medical nebulizer applications. [0004] Nebulizers are commonly used to deliver medication to persons with respiratory ailments. For example, bronchodialators, which are used to open airway passages, are commonly administered with nebulizers. A nebulizer changes liquid medication into a fine, atomized mist or vapor. The medicinal vapor is inhaled through a mouthpiece or mask and the atomized medication is able to penetrate deeply into one's airways because of its fine particle size. The liquid medicine is atomized by mixing it with compressed air or oxygen. [000...

AI Technical Summary

Benefits of technology

[0008] The present invention provides a pump, particularly designed for use with a medical nebulizer having improved noise, vibration and manufacturing characteristics.

[0012] The present invention thus provides a compact piston pump having a foam housing providing very low operating vibration and noise such that it is particularly suitable for use in a medical nebulizer device. The pump can have a uni-body construction in which the pump components are pre-assembled and insert molded with the foam forming the housing. Or, the pump can have a split housing in which the parts are assembled with a special ring providing a simple pin and socket connection. Further, the reciprocating drive components of the pump assembly can be suspended in the housing by individual springs or spring stacks to further isolate the housing from vibration caused by the reciprocating elements of the assembly, and thereby reduce noise. The integral air inlet and outlet ports simplify assembly and cost by eliminating the need for separate air lines or tubing.

Problems solved by technology

Persons with significant respiratory problems often require multiple nebulizer treatments every day, each taking several minutes to administer.

Quiet operation of the compressor can be obtained by insulating the housing, however, this adds bulk and can cause cooling problems.

Mufflers can be added at the compressor exhaust, however, this adds hardware and cost.

Conventional metal housings are prone to vibrate in response to the reciprocating components during operation of the pump at an audible frequency that may be too loud for suitable for hospital and home use.

However, this adds parts and complicates assembly, thereby increasing unit costs.

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