Air filtering and distribution for laminar flow clean room

Claim 2

An air filtering and distribution structure for use in an environmentally controlled enclosure, said structure comprising: a first planar section spaced a predetermined distance from one surface of said enclosure, means for diffusing air through the first planar section such that the air is filtered thereby; and a second planar section spaced a predetermined distance from and generally parallel to said first section, the second planar section comprising a plurality of membrane diffusion panels, each membrane diffusion panel comprising a frame having an open area, and a porous membrane sheet having a predetermined porosity mounted onto and extending over the frame and the open area therein with the porosity providing a predetermined resistance to flow of the air whereby during operation a slight pressure is developed between the first planar section and second planar section causing any leakage of air through the first section to be away from the controlled enclosure so that the membrane diffusion panels cooperate to provide uniform air flow through the second planar section such that the environmentally controlled enclosure achieves higher cleanliness levels for a given filtered air exchange rate than would be obtained without the membrane diffusion panels.

Claim 3

The air filtering and distribution structure as defined in claim 1 wherein the first section comprises a mixed array of panels having air filter panels and other panels, and wherein a clean air plenum is defined between the first planar section and the second planar section.

Claim 4

The air filtering and distribution structure as defined in claim 2 wherein the membrane diffusion panel is translucent.

Claim 5

The air filtering and distribution structure as defined in claim 3 wherein the membrane sheet comprises a structure of continuous filament fibers.

Claim 6

The air filtering and distribution structure as defined in claim 4 wherein the membrane sheet further comprises a spunbound structure of polyester fibers.

Claim 7

The air filtering and distribution structure as defined in claim 3 wherein the mixed array of panels of the first planar section further comprises at least one light module mounted therein to provide lighting for the enclosure.

Claim 8

The air filtering and distribution structure as defined in claim 4 wherein the membrane sheet is mounted on the ceiling panel and the ceiling panel comprises a plastic panel having a multiplicity of apertures extending therethrough.

Claim 9

The air filtering and distribution structure as defined in claim 7 wherein the ceiling panel has the form of a grid having substantially parallel longitudinal and lateral bars defining apertures therebetween.

Claim 10

The air filtering and distribution structure as defined in claim 8 wherein the membrane diffusion panel further comprises retainer clips to secure the fiber sheet to the ceiling panel.

Claim 11

The air filtering and distribution structure as defined in claim 1 further comprising an air filter located at an air inlet to the enclosure wherein all air entering the enclosure passes through the air filter and wherein a clean air plenum is defined between the first planar section and a surface of the enclosure.

Claim 12

The air filtering and distribution structure as defined in claim 10 further comprising: a return unit located on a side of the enclosure at floor level into which air passes from the enclosure; a vertical duct located on the side of the enclosure which houses the return unit in a lower portion thereof; a fan for increasing the flow pressure of the air located in a central portion of the duct; the air filter, located in an upper portion of the duct and adapted to filter air blown by the fan into a clean air plenum area.

Claim 13

An environmentally controlled enclosure having an air filtering and distributing structure as defined in claim 11 wherein the first planar section housing light modules and air filtering means, and the second planar section, disposed below the first planar section, houses translucent membrane diffusion panels for uniformly distributing air through the enclosure.

Claim 14

An environmentally controlled enclosure having an air filtering and distributing structure as defined in claim 10 wherein the membrane diffusion panels comprise a fibrous panel mounted on a grid shaped ceiling panel.

Claim 15

A membrane diffusion panel for distributing air in a filtered environmentally controlled enclosure, said panel comprising: a translucent support panel having a plurality of apertures extending therethrough wherein the panel comprises at least 50 percent open area for allowing air passage therethrough; a translucent porous membrane sheet mounted on the support panel comprises a structure of continuous filament fibers, the membrane sheet having porosity and extending over the open area with the porosity providing a predetermined resistance to flow of the air so that the membrane diffision panel cooperates to provide uniform air flow through the environmentally controlled enclosure such that the environmentally controlled enclosure achieves higher cleanliness levels for a given filtered air exchange rate than would be obtained without the membrane diffusion panel.

Claim 16

A membrane diffusion panel for distributing air in a filtered environmentally controlled enclosure, said panel comprising: a translucent support panel having a plurality of apertures extending therethrough wherein the panel comprises at least 50 percent open area for allowing air passage therethrough; a translucent porous membrane sheet mounted on the support panel comprises a structure of continuous filament fibers, the membrane sheet having porosity and extending over the open area with the porosity providing a predetermined resistance to flow of the air so that the membrane diffision panel cooperates to provide uniform air flow through the environmentally controlled enclosure such that the environmentally controlled enclosure achieves higher cleanliness levels for a given filtered air exchange rate than would be obtained without the membrane diffusion panel.

Claim 17

An air filtering and distribution structure of use in an environmentally controlled enclosure, said structure comprising: a first planar section spaced a predetermined distance from one surface of said enclosure thereby defining a supply air plenum therebetween, said first section comprising a mixed array panels having air filter panels, blank panels and light modules; and a second planar section spaced a predetermined distance from and generally parallel to said first section defining a clean air plenum between the first planar section and the second planar section, the second planar section comprising a plurality of membrane diffusion panels wherein each membrane diffusion panel comprises a translucent plastic ceiling panel having the form of a grid having substantially parallel longitudinal and lateral bars defining apertures therebetween, and a fiber sheet comprising a structure of continuous filament spunbound polyester fibers having a predetermined porosity mounted onto and extending over the ceiling panels and the apertures therein with the porosity providing a predetermined resistance to flow of the air whereby during operation a slight pressure is developed between the first planar section and second planar section causing any leakage of air through the first section to be away from the controlled enclosure so that the membrane diffusion panels cooperate to provide uniform air flow through the second planar section.

Claim 18

An air filtering and distribution structure of use in an environmentally controlled enclosure, said structure comprising: a first planar section spaced a predetermined distance from one surface of said enclosure thereby defining a supply air plenum therebetween, said first section comprising a mixed array panels having air filter panels, blank panels and light modules; and a second planar section spaced a predetermined distance from and generally parallel to said first section defining a clean air plenum between the first planar section and the second planar section, the second planar section comprising a plurality of membrane diffusion panels wherein each membrane diffusion panel comprises a translucent plastic ceiling panel having the form of a grid having substantially parallel longitudinal and lateral bars defining apertures therebetween, and a fiber sheet comprising a structure of continuous filament spunbound polyester fibers having a predetermined porosity mounted onto and extending over the ceiling panels and the apertures therein with the porosity providing a predetermined resistance to flow of the air whereby during operation a slight pressure is developed between the first planar section and second planar section causing any leakage of air through the first section to be away from the controlled enclosure so that the membrane diffusion panels cooperate to provide uniform air flow through the second planar section.