Float actuated evaporator heater

Claim 2

A float actuated heater apparatus for regulating the level of defrost water in a condensation collecting receiver pan of a domestic refrigerator comprising an immersion electric heater body having resistance heaters embedded therein including an electrical heating circuit for energizing said resistance heaters, a pair of spaced flat support arms pivotally mounted on said heater body about a horizontal axis, a float on said float arms responsive to a rise or fall of water level in the collecting pan, said heat body including a normally open reed switch located thereon operative to open and close the circuit of said resistance heaters, said reed switch having a pair of reeds sealed in a glass tube each having a mounting portion and a contacting portion spaced longitudinally on the reed, said reeds having their contacting portions in overlying relationship with one another, the longitudinal axis of said reed switch located parallel to the horizontal pivotal axis of said float arms, a magnet incorporated with said float so as to be movable in an arcuate path in accordance with the float elevation toward and away from said reed switch, the path of said magnet defining a vertical plane substantially bisecting said reed switch contacting portions whereby said reed switch is sensitive to a relatively small rise of the water level in the pan to cause said magnet to close said reed switch contacts and energize said heater elements, and whereby a relatively small decrease in the water level pivots said magnet away from said reed switch contacts allowing them to open thereby deenergizing said resistance heaters and maintaining in said pan a minimum volume of water at a level sufficient to maintain said heating assembly partially submerged in the water.

Claim 3

A float actuated heater apparatus for regulating the level of defrost water in a condensation collecting receiver pan of a domestic refrigerator comprising a rectangular shape in plan immersion electric heater body having resistance heaters embedded therein including an electrical heating circuit for energizing said resistance heaters, a pair of spaced float arms pivotally mounted on a horizontal axis at points on said heater body side walls adjacent the forward lower edge of said heater body, a float on said float arms and extending therebetween substantially coextensive with the front wall of said heater body, said heater body including a normally open reed switch embedded therein at a point adjacent the front wall upper edge of said heater bOdy operative to open and close the circuit of said resistance heaters, said reed switch having its longitudinal axis parallel to said float arm pivotal axis and including a pair of reeds sealed in a glass tube each reed having a mounting portion and a contacting portion spaced longitudinally thereon, said reeds having their contacting portions in overlying relationship with one another, the longitudinal axis of said reed switch located parallel to the horizontal pivotal axis of said float arms, a magnet incorporated with said float so as to be movable in an arcuate path in accordance with the float movement toward and away from said reed switch, said float operative to swing in an upward direction from a substantially horizontal plane to contact said heater body adjacent said front wall upper edge to limit the uppermost extent of its pivotal rising motion when said magnet is disposed adjacent the upper edge of said heater body, the path of said magnet defining a vertical plane substantially bisecting said reed switch contacting portions whereby said reed switch is sensitive to a relatively small rise of the water level in the pan to cause said magnet to close said reed switch contacts and energize said heater element, and whereby a relatively small decrease in the water level pivots said magnet away from said reed switch contacts allowing them to open thereby deenergizing said resistance elements and maintaining in said pan a minimum volume of water at a level sufficient to maintain said heater body partially submerged in the water.

Claim 4

A float actuated heater apparatus for regulating the level of defrost water in a condensation collecting receiver pan of a domestic refrigerator comprising a rectangular shape in plan immersion electric heater body having resistance heaters embedded therein including an electrical heating circuit for energizing said resistance heaters, a pair of spaced float arms pivotally mounted on a horizontal axis at points on said heater body side walls adjacent the forward lower edge of said heater body, a float on said float arms and extending therebetween substantially coextensive with the front wall of said heater body, said heater body including a normally open reed switch embedded therein at a point adjacent the front wall upper edge of said heater bOdy operative to open and close the circuit of said resistance heaters, said reed switch having its longitudinal axis parallel to said float arm pivotal axis and including a pair of reeds sealed in a glass tube each reed having a mounting portion and a contacting portion spaced longitudinally thereon, said reeds having their contacting portions in overlying relationship with one another, the longitudinal axis of said reed switch located parallel to the horizontal pivotal axis of said float arms, a magnet incorporated with said float so as to be movable in an arcuate path in accordance with the float movement toward and away from said reed switch, said float operative to swing in an upward direction from a substantially horizontal plane to contact said heater body adjacent said front wall upper edge to limit the uppermost extent of its pivotal rising motion when said magnet is disposed adjacent the upper edge of said heater body, the path of said magnet defining a vertical plane substantially bisecting said reed switch contacting portions whereby said reed switch is sensitive to a relatively small rise of the water level in the pan to cause said magnet to close said reed switch contacts and energize said heater element, and whereby a relatively small decrease in the water level pivots said magnet away from said reed switch contacts allowing them to open thereby deenergizing said resistance elements and maintaining in said pan a minimum volume of water at a level sufficient to maintain said heater body partially submerged in the water.

Claim 5

The float actuated heater apparatus as defined in claim 2 wherein said float is rectangular in cross section and said magnet is in the form of a disc embedded in said float such that an arcuate section of said disc extends outwardly from a side wall of said float towards said heater body front wall, said arcuate section operative to contact said heater body front wall to limit the uppermost extent of the pivotal rising motion of said float.