Hermetic motor compressor unit having a hermetic terminal with electrically insulating anti-tracking cap

In a hermetic motor compressor unit having a housing with an opening therein, a hermetic terminal mounted in the housing opening and adapted for carrying electric current from the exterior of the housing to the interior thereof, comprising:

• a metallic cup-shaped body member including an open end facing the interior of the housing, a closed end having an inner surface facing the interior of the housing, and a generally cylindrical sidewall therebetween, said closed end having a plurality of openings providing communication therethrough;
• a plurality of current-conducting pins corresponding to said plurality of openings in said body member, each pin being received within and extending through a respective opening;
• an electrically insulating cap member including a bottom surface and a plurality of through passages corresponding to said plurality of current-conducting pins, each of said through passages being defined by a respective inner passage wall, said bottom surface of said cap member being secured to said inner surface of said closed end with each one of said pins extending through a respective one of said through passages, said cap member defining an oversurface distance between said metallic body member and each of said current-conducting pins;
• and
• means for protecting a portion of said oversurface distance from contaminants within said housing, said means including an annular gap defined between each said pin and said inner passage wall of a corresponding said through passage, said annular gap extending axially along said pin and having an open gap end and a closed gap end, and said inner passage wall and corresponding said pin being closely spaced from one another at an axial location toward said open gap end, whereby said annular gap inhibits the deposit of contaminants on said protected portion of said oversurface distance.

In a hermetic motor compressor unit having a housing with an opening therein, a hermetic terminal mounted in the housing opening and adapted for carrying electric current from the exterior of the housing to the interior thereof, comprising:

• a metallic cup-shaped body member including an open end facing the interior of the housing, a closed end having an inner surface facing the interior of the housing, and a generally cylindrical sidewall therebetween, said closed end including a plurality of collar portions defining respective pin openings providing communication through said closed end;
• a plurality of current-conducting pins corresponding to said plurality of openings in said body member, each pin being received within and extending through a respective opening;
• means hermetically sealing each of said pin openings with a corresponding pin received therein, said means including an electrically insulating seal material disposed intermediate each of said pins and a corresponding said collar portion, said inner surface and said collar portions defining an inwardly facing contoured surface;
• an electrically insulating cap member having a contacting surface corresponding substantially in shape to said inwardly facing contoured surface, said cap member including a plurality of apertures therein corresponding to said plurality of current-conducting pins, said cap member being positioned relative to said body member such that said contacting surface is adjacent said contoured surface and said pins extend through corresponding said apertures;
• and
• electrically insulating bonding means, intermediate said contacting surface of said cap member and said contoured surface, securing said cap member to said body member, said bonding means comprising a substantially uniform layer of electrically insulating bonding material, said substantially uniform layer of bonding material both bonding the cap member to the body member and filling in any irregular spaces between the substantially corresponding contours thereof.