Wet motor gerotor fuel pump with vapor vent valve and improved flow through the armature

A wet motor gerotor pump for pumping a liquid of low electrical conductivity from a liquid source, said pump comprising:

• a pump case having one end, an opposite end and a flow axis therethrough, said pump case further comprising an inlet end bore at said one end adapted to communicate with said liquid source and means for sealing said pump case;
• an inlet chamber adjacent said inlet end bore;
• a motor chamber located in said opposite end of said pump case;
• a pump chamber interposed said motor chamber and said inlet chamber:
• inlet housing means mouned in said pump chamber, said inlet housing means comprising an annular hub protruding into said inlet chamber, said inlet housing means further comprising a gerotor cavity having a gerotor outlet port, said gerotor cavity disposed about a gerotor axis located parallel to and displaced a predetermined distance in an eccentric radial direction from said flow axis;
• outlet housing means having pump outlet means adapted to communicate liquid from said pump and further comprising a second means for sealing coupled to said means for sealing said pump case to said outlet housing means, said outlet housing means further comprising vapor vent means;
• electric motor means comprising:
• armature means comprising an armature shaft with a first and a second end rotatably supported, respectively, at said inlet housing means and said outlet housing means, said armature means further comprising drive hub means having an axially extending portion;
• and
• first and second magnet means, each of said first and second magnet means further comprising an inner and an outer axial surface extending in a direction along said flow axis about said armature means, a first and a second side surface extending in a direction along said flow axis, and a first and a second end surface;
• gerotor pump means located in said gerotor cavity, said gerotor pump means comprising an inner pump gear, an outer pump gear, and means for driving said inner and outer pump gears, said gerotor pump means further comprising a locating hole spaced from said gerotor axis;
• means for separating said liquid from said armature means as said liquid flows from said gerotor cavity to said outlet housing means, said means for separating said liquid from said armature means comprising keeper means separating one of said first and second side surfaces of said first magnet means from one of said first and second side surfaces of said second magnet means to define a first axial flow passage between said gerotor cavity and said outlet housing means and between said first and second magnet means substantially along said flow axis, said keeper means comprising first and second spaced apart protrusions extending axially therefrom, said first and second spaced apart protrusions defining a fluid entrance therebetween, one of said first and second spaced apart protrusions abutting against said pump chamber, the other of said first and second spaced apart protrusions having an end with a first step and a second step, one of said first step and said second step abutting against said pump chamber, the other of said first step and said second step extending into said locating hole in said gerotor pump means, such that said keeper means establishes said first axial flow passage past said armature means substantially free of turbulence and flow restrictions to thereby allow liquid to be pumped at substantially higher flow rates at armature currents substantially lower than without said means for separating, whereby said first axial flow passage allows liquid to be pumped about said armature means and to thereby improve pumping efficiency and performance;
• and
• magnet spacing means positioned between said first and second magnet means for spacing said first and second side surfaces of said first magnetmeans circumferentially with respect to said first and second side surfaces of said second magnet means;
• whereby said gerotor pump means pumps liquid from said source through said inlet chamber, past said gerotor cavity through said gerotor outlet port into said motor chamber, then along said means for separating said liquid from said armature means into said outlet housing means, said vapor vent means permitting vapor to vent from said gerotor pump means for a predetermined period, said vapor vent means further terminating the venting of vapor upon the pumped liquid being communicated to said vapor vent means.

A wet motor gerotor pump for pumping a liquid of low electrical conductivity from a liquid source, said pump comprising:

• a pump case having one end, an opposite end and a flow axis therethrough, said pump case further comprising an inlet end bore at said one end adapted to communicate with said liquid source and means for sealing said pump case;
• an inlet chamber adjacent said inlet end bore;
• a motor chamber located in said opposite end of said pump case;
• a pump chamber interposed said motor chamber and said inlet chamber;
• inlet housing means mounted in said pump chamber, said inlet housing means comprising an annular hub protruding into said inlet chamber, said inlet housing means further comprising a gerotor cavity having a gerotor outlet port, said gerotor cavity disposed about a gerotor axis located parallel to and displaced a predetermined distance in an eccentric radial direction from said flow axis;
• outlet housing means having pump outlet means adapted to communicate liquid from said pump and further comprising a second means for sealing coupled to said means for sealing said pump case to said outlet housing means, said outlet housing means further comprising vapor vent means;
• electric motor means comprising:
• armature means having an axial length and comprising an armature shaft with a first and a second end rotatably supported, respectively, at said inlet housing means and said outlet housing means, said armature means further comprising drive hub means having an axially extending portion;
• and
• first and second magnet means, each of said first and second magnet means further comprising an inner and an outer axial surface extending in a direction along said flow axis about said armature means, a first and a second side surface extending in a direction along said flow axis, and a first and a second end surface;
• magnet spacing means positioned between said first and second magnet means for spacing said first and second side surfaces of said first magnet means circumferentially with respect to said first and second side surfaces of said second magnet means;
• gerotor pump means located in said gerotor cavity, said gerotor pump means comprising an inner pump gear, an outer pump gear, and means for driving said inner and outer pump gears, said gerotor pump means further comprising a locating hole spaced from said gerotor axis;
• means for separating said liquid from said armature means as said liquid flows from said gerotor cavity to said outlet housing means, said means for separating said liquid from said armature means comprising keeper means, said keeper means comprising tunnel means having a central bridge portion defining a first axial flow passage and extending axially along said armature length, said central bridge portion further being bounded by a first leg portion and a second leg portion, and first and second spaced apart protrusions extending axially therefrom, said first and second spaced apart protrusions defining a fluid entrance therebetween, said central bridge portion of said tunnel means radially separating said first axial flow passage from said armature means, each said leg portion extending radially outwards from said central bridge portion and separating said one of said first and second side surfaces of said first magnet means from said one of said first and second side surfaces of said second magnet means, said tunnel means further comprising an extension portion extending axially towards said gerotor pump means and adapted to abut thereagainst, said first and second leg portions each comprising tab means interposed said gerotor pump means and one of said first and second end surfaces of each of said first and second magnet means, whereby said tab means cooperate with said extension portion to axially space said first and second magnet means a predetermined axial distance from said gerotor pump means so as to allow liquid to flow into said first axial flow passage, such that said keeper means establishes said first axial flow passage past said armature means substantially free of turbulence and flow restrictions and to thereby allow liquid to be pumped at substantially higher flow rates at armature currents substantially lower than without said means for separating, whereby said first axial flow passage allows liquid to be pumped about said armature means and to thereby improve pumping efficiency and performance;
• and
• said means for separating said liquid from said armature means further coprising spring means circumferentially biasing the other of said first and second side surfaces of said first magnet means from the other of said first and second side surfaces of said second magnet means to establish a second axial flow passage extending along said flow axis between said first and second magnet means;
• whereby said gerotor pump means pumps liquid from said source through said inlet chamber, past said gerotor cavity through said gerotor outlet port into said motor chamber, then along said means for separating said liquid from said armature means into said outlet housing means, said vapor vent means permitting vapor to vent from said gerotor pump means for a predetermined period, said vapor vent means further terminating the venting of vapor upon the pumped liquid being communicated to said vapor vent means.