US 6,442,955 B1Granted

Condensate overflow safety switch

OwnerStuart Peter Oakner, Mark Thomas Brannick +1inventors

InventorsStuart Peter Oakner, Mark Thomas Brannick, Donna Ellen Oakner Brannick

Life of this patent

Estimating the term…

Loading patent…

Abstract

A safety switch that can be used with an air handling system is disclosed. The air-cooling system includes a drain pan for collecting liquid condensed on the evaporator coils. The pan is fluidwise connected to a T- or L-shaped tubular structure, installable at any slope from horizontal to vertical, in which the switch is mounted and the switch is electrically connected to a circuit of the system, a power circuit or an alarm circuit. The switch has an annular float containing an annular magnet mounted about a tube in which is sealed a reed switch. The float ascends or descends based on the level of liquid within the tubular structure. Dependent upon a predetermined level of liquid within the tubular structure the float will move along the tube to open or close the reed switch to either disrupt operation of the air handling system or operate an alarm circuit.

Claims30

Dependent claims

An air-cooling system comprising:

means for cooling air;
at least one of a first circuit connected to means for controlling supply of power to said means for cooling air or a second circuit connected to an alarm circuit;
air handling means for cooling warm air, said air handling means having heat exchanger coils for containing a cold material for cooling the warm air;
a drain pan for receiving condensate liquid formed on said exchanger coils, said drain pan having at least one outlet;
and
tube means fluidwise connected to said at least one outlet for conveying liquid away from said drain pan, said tube means including:
a safety switch device having a tubular structure, said tubular structure having a plurality of open ends, a first open end of said plurality of open ends being fluidwise connected to one of said at least one outlet, and an overflow switch assembly mounted within a second open end of said plurality of open ends, said overflow switch assembly including:
a magnetically driven reed switch, said reed switch having sealed contacts, each of said contacts being electrically connected by at least one electrical connection to one of said first circuit and said second circuit;
a mounting cap for mounting said reed switch within said second open end, said mounting cap having an outer face, and inner face, and an aperture therebetween;
a hollow tube having a closed end portion, an open end portion, and an outer surface extending therebetween, said hollow tube being disposed through said aperture, a stop means affixed to said closed end portion, and sealing means for sealingly closing said open end portion with said reed switch therein and said electrical connections extending through said sealing means;
and
attachment means for adjustably attaching said open end portion adjacent to said outer face.

9 more elements

An overflow safety switch device comprising:

a tubular structure for receiving and monitoring liquid draining from a drain pan, said structure having a plurality of open ends, a first open end of said plurality of open ends being fluidwise connected to the drain pan;
an overflow switch assembly mounted in a second open end of said plurality of open ends, said overflow switch assembly including:
a magnetically driven reed switch, said reed switch having sealed contacts, each of said contacts having at least one electrical connection to one of a first circuit for de-activating production of the liquid and a second circuit for activating an alarm;
a mounting cap for mounting said reed switch within said second open end, said mounting cap having an outer face, an inner face and an aperture therebetween;
a hollow tube having a closed end portion, an open end portion, and an outer surface extending therebetween, said hollow tube being disposed through said aperture, a stop means affixed to said closed end portion, and sealing means for sealingly closing said open end portion with said reed switch within said hollow tube and said electrical connections extending through said sealing means;
and
attachment means for adjustably attaching said open end portion adjacent to said outer face.

4 more elements

A method for preventing condensate liquid overflow from a drain pan receiving condensate liquid from an air handling unit comprising the steps of:

installing a tube means fluidwise connected to an outlet for conveying condensate liquid away from the drain pan, said tube means including:
a safety switch device having a tubular structure, said tubular having a plurality of open ends, a first open end of said plurality of open ends being fluidwise connected to the outlet;
and
an overflow switch assembly mounted within a second open end of said plurality of open ends;
said assembly including:
a magnetically driven reed switch, said reed switch including sealed contacts biased to closed, each of said contacts having at least one electrical connection to a circuit connected to means for controlling supply of power to the air handling unit;
a mounting cap for mounting said reed switch within said second open end, said mounting cap having an outer face, an inner face and an aperture therebetween;
a hollow tube having a closed end portion, an open end portion, an outer surface extending therebetween, and a stop means affixed to said closed end portion, said hollow tube being disposed through said aperture, and sealing means for sealingly closing said open end portion with said reed switch within said hollow tube and said electrical connections extending therethrough;
attachment means for adjustably attaching said open end portion adjacent to said outer face;
and
a buoyant annular float body moveable along said outer surface between said stop means and a predetermined level toward said inner face, said float body having a first face end and a second face end and an annular magnet disposed therebetween for magnetically driving said contacts, said annular magnet being disposed closer to said first face end than said second face end, and
electrically connecting said electrical connection into said circuit.

9 more elements

A method for alarming of potential condensate liquid overflow from a drain pan receiving condensate liquid from an air handling unit comprising the steps of:

installing a tube means fluidwise connected to an outlet for conveying condensate liquid away from the drain pan, said tube means including:
a safety switch device having a tubular structure, said tubular having a plurality of open ends, a first open end of said plurality of open ends being fluidwise connected to the outlet, and an overflow switch assembly mounted within a second open end of said plurality of open ends;
said assembly including:
a magnetically driven reed switch, said reed switch including sealed contacts biased to closed, each of said contacts having at least one electrical connection to a circuit connected to means for signaling an alarm;
a mounting cap for mounting said reed switch within said second open end, said mounting cap having an outer face, an inner face and an aperture therebetween;
a hollow tube having a closed end portion, an open end portion, an outer surface extending therebetween, and a stop means affixed to said closed end portion, said hollow tube being disposed through said aperture, and sealing means for sealingly closing said open end portion with said reed switch within said hollow tube and said electrical connections extending therethrough;
attachment means for adjustably attaching said open end portion adjacent to said outer face;
and
a buoyant annular float body moveable along said outer surface between said stop means and a predetermined level toward said inner face, said float body having a first face end and a second face end and an annular magnet disposed therebetween for magnetically driving said contacts, said annular magnet being disposed closer to said first face end than said second face end, and
electrically connecting said electrical connections into said circuit.

7 more elements

A method for preventing condensate liquid overflow from a drain pan receiving condensate liquid from an air handling unit comprising the steps of:

installing a tube means fluidwise connected to an outlet for conveying condensate liquid away from the drain pan, said tube means including:
a safety switch device having a T-shaped tubular structure formed from one of the group of plastic and metal, said tubular structure having a first open end, a second open end and a third open end, said first open end and said second open end being opposite one another;
and an overflow switch assembly mounted within one of said first open end and said third open end;
said assembly including:
an electrical switch having electrical contacts, each of said contacts having at least one electrical connection to at least one circuit of the group of a circuit for controlling supply of power to the air handling unit and an alarm circuit;
a mounting cap for mounting said switch within one of said first open end and said third open end, said mounting cap having an outer face, an inner face and an aperture therebetween;
a rod having a first end portion and a second end portion, said rod being disposed through said aperture such that said first end portion extends beyond said outer face;
attachment means for attaching said first end portion adjacent to said outer face;
and
a buoyant float body suspended at said second end portion, said float body being moveable to a predetermined level from said inner face;
and
electrically connecting said at least one electrical connections of each of said contacts to at least one of said circuits.

9 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/861,551Filed 22 May 2001 · continuation in part
Priority: 6 Mar 2001
Published: US 2002/0124582 A112 Sep 2002
Granted: 3 Sep 2002
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

F24F 13/222
Means for preventing condensation or evacuating condensate: for evacuating condensate
F25D 21/14
Defrosting; Preventing frosting; Removing condensed or defrost water: collecting or removing condensed and defrost water; Drip trays
G01F 23/74
Using magnetically actuated indicating means: for sensing changes in level only at discrete points
H01H 36/02
Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding:…