Electric pump for use in filtering system of a tropical fish tank or the like

An electrically driven pump for circulating liquid in a fish tank or the like comprising:

• a stator housing including a hollow boss having a cylindrical cavity in one wall of said housing and a hollow connecting portion extending from said cylindrical cavity to a slot formed in a side wall of said housing;
• a motor stator contained in said housing and being disposed about said boss;
• a rotor separably secured to said stator housing and including a first cylindrical chamber separably registering with said stator housing cylindrical cavity, a second chamber offset from said first chamber and disposed proximate said stator housing side wall and a channel extending between said first and second chambers and separably registering with said stator housing hollow connecting portion;
• and
• an impeller-rotor assembly located in said rotor housing and including a shaft, a magnetic rotor mounted on said shaft and disposed in said first cylindrical chamber and rotatable in response to the magnetic field produced by said stator and an impeller rotatable with said rotor, said second chamber having a liquid outlet opening formed therein and said rotor housing having formed within a liquid inlet opening in the vicinity of the lower end of said impeller-rotor assembly whereby water entering said inlet opening bathes said lower end of said assembly.

A electrically driven pump for circulating liquid in a fish tank or the like, comprising:

• a stator;
• a housing for said stator;
• an impeller-rotor assembly comprising a shaft, a magnetic rotor mounted on said shaft for rotation in response to the electromagnetic field produced by said stator, and an impeller rotatable with said rotor;
• a housing defining a chamber for supporting said impeller-rotor assembly, said impeller-rotor housing having inlet and outlet openings defining a flow path for said liquid through said chamber;
• said stator housing having a hollow boss defining a generally cylindrical cavity in one wall of said stator housing and a connecting portion extending from said cylindrical cavity to one sidewall of said stator housing, said one sidewall having a slot therein communicating with the cavity defined by said connecting portion;
• said impeller-rotor housing including a cylindrical member defining a cylindrical chamber for the upper end of said impeller-rotor assembly and being complementary to the cylindrical cavity defined by said boss for seating therein and said impeller-rotor housing including another cylindrical member defining another cylindrical chamber, said outlet opening being formed in said other cylindrical member, said impeller-rotor housing also including a connecting member defining a connecting channel providing liquid communication between said cylindrical chamber in said impeller-rotor housing, said connecting member being dimensioned for seating in the cavity defined by said connecting portion of said boss when said stator and impeller-rotor housings are interengaged, said rotor being mounted on said shaft at the upper end of said impeller-rotor assembly and said stator including a lamination stack disposed about said boss in said stator housing;
• and
• means for releasably securing said housings together with said rotor in the vicinity of said stator when said housings are interengaged.