Hermetic motor protector

Claim 2

A motor protector comprising an electrically conductive header plate, a pair of terminal posts extending through said plate in spaced, electrically insulated relation to the plate and to each other, a rigid electrically conductive contact arm secured in electrically conductive relation to one of said posts to extend in cantilever relation therefrom, said arm carrying fixed contact means at the distal end of said arm, a first, rigid, electrical resistance heater secured in electrically conductive relation to the other of said posts to extend in cantilever relation therefrom in generally parallel relation to said arm, an electrically conductive thermally responsive snapacting member having a movable contact secured to one end thereof and having a support secured to an opposite end of said member, said support having a portion extending out of the general plane of said member secured to a portion of said first heater for disposing said member in selected heat transfer relation to said first heater so that said movable contact engages and disengages said fixed contact to close and open a circuit in response to snap-acting movement of said member, and a relatively wide and thin striplike electrical resistance element defining a second heater of generally U-shaped configuration having one end thereof secured to said plate and having its opposite end secured to said portion of said first heater for supporting said second heater in selected heat transfer relation to said thermally responsive member.

Claim 3

A motor protector as set forth in claim 1 wherein said U-shaped heater has bottom and leg portions disposed in a plane and wherein said relatively wide dimension of said striplike element extends in said plane, said U-shaped heater being disposed with said plane thereof generally parallel to the plane of said thermally responsive member.

Claim 4

A motor protector as set forth in claim 2 having portions of said striplike heater element embossed to provide said portions with a channellike cross-sectional configuration.

Claim 5

A motor protector as set forth in claim 2 wherein one of said legs of said U-shaped heater is substantially straight and has an embossed portion extending therealong providing said heater with selected rigidity, the other of said legs defining a tortuous path having a general direction parallel to said one leg providing said heater with a substantial effective length.

Claim 6

A hermetically sealed motor protector comprising an electrically conductive header plate, a pair of terminal posts extending through said plate in sealed relation to said plate and in spaced, electrically insulated relation to said plate and to each other, a rigid electrically conductive contact arm having two angularly disposed flanges and having one of said flanges welded to one of said terminal posts so that said other flange extends away from said plate in cantilever relation from said terminal post, said arm carrying a fixed contact in a first selected plane at the distal end of said arm, a first rigid electrical resistance heater element having two angularly diSposed flanges and having one of said flanges welded to the other of said posts so that a flange of said heater element extends in cantilever relation from said other post in generally parallel relation to said arm for disposing a distal portion of said extending flange in a second selected plane, an electrically conductive thermally responsive snap-acting member having a movable contact secured to one end thereof, a support having two angularly disposed flanges and having one of said flanges secured in electrically conductive relation to an opposite end of said member so that the other of said support flanges extends out of the general plane of said member, said other support flange being welded to a second portion of said extending flange of said first heater for disposing said thermally responsive member in selected heat transfer relation to said first heater and for disposing said one end of said member so that said movable contact engages and disengages said fixed contact and so that said one member end disengages and engages said distal portion of said first heater to close and open a circuit in response to snap-acting movement of said member, a relatively wide and thin striplike electrical resistance element defining a second heater of generally U-shaped configuration having a bottom portion and two leg portions disposed in a plane and having said relatively wide dimension of said striplike element extending in said heater plane, said U-shaped heater having flanges at said leg ends welded to said plate and to said second portion of said first heater respectively for supporting said second heater in selected heat transfer relation to said member, said welds being arranged so that a line normal to the plane of each of said welds lies substantially parallel to said first and second selected planes, and a cup-shaped body having its rim secured in sealed relation to said plate for enclosing said heaters, arm, contacts, support and member.

Claim 7

A hermetically sealed motor protector comprising an electrically conductive header plate, a pair of terminal posts extending through said plate in sealed relation to said plate and in spaced, electrically insulated relation to said plate and to each other, a rigid electrically conductive contact arm having two angularly disposed flanges and having one of said flanges welded to one of said terminal posts so that said other flange extends away from said plate in cantilever relation from said terminal post, said arm carrying a fixed contact in a first selected plane at the distal end of said arm, a first rigid electrical resistance heater element having two angularly diSposed flanges and having one of said flanges welded to the other of said posts so that a flange of said heater element extends in cantilever relation from said other post in generally parallel relation to said arm for disposing a distal portion of said extending flange in a second selected plane, an electrically conductive thermally responsive snap-acting member having a movable contact secured to one end thereof, a support having two angularly disposed flanges and having one of said flanges secured in electrically conductive relation to an opposite end of said member so that the other of said support flanges extends out of the general plane of said member, said other support flange being welded to a second portion of said extending flange of said first heater for disposing said thermally responsive member in selected heat transfer relation to said first heater and for disposing said one end of said member so that said movable contact engages and disengages said fixed contact and so that said one member end disengages and engages said distal portion of said first heater to close and open a circuit in response to snap-acting movement of said member, a relatively wide and thin striplike electrical resistance element defining a second heater of generally U-shaped configuration having a bottom portion and two leg portions disposed in a plane and having said relatively wide dimension of said striplike element extending in said heater plane, said U-shaped heater having flanges at said leg ends welded to said plate and to said second portion of said first heater respectively for supporting said second heater in selected heat transfer relation to said member, said welds being arranged so that a line normal to the plane of each of said welds lies substantially parallel to said first and second selected planes, and a cup-shaped body having its rim secured in sealed relation to said plate for enclosing said heaters, arm, contacts, support and member.