Offset-drive magnetically driven gear-pump heads and gear pumps comprising same

A magnetically driven gear-pump head, comprising:

• a pump housing comprising a first plate and a second plate that define therebetween a pump cavity extending along a pump axis, the pump housing defining a pump inlet for delivering liquid into the pump housing and a pump outlet for delivering fluid from the pump housing;
• a magnet cup extending from the second plate and containing a driven magnet that is rotatable inside the magnet cup about the pump axis, the driven magnet comprising a first driving gear;
• a pump driving gear having a first gear axis and a pump driven gear having a second gear axis, the gear axes being parallel to but laterally offset from the pump axis on first and second sides, respectively, of the pump axis, the pump gears being contained in the pump cavity, being journaled in respective bearings in the first and second plates, and being configured to interdigitate with each other such that rotation of the pump driving gear causes a corresponding contrarotation of the pump driven gear in the pump cavity, the pump driving gear comprising a second driving gear configured to interdigitate with the first driving gear such that rotation of the driven magnet causes, via the first and second driving gears, corresponding rotations of the pump driving gear and pump driven gear in a manner by which liquid is pumped through the pump housing from the pump inlet to the pump outlet;
• and
• a bearing-flush circuit configured to flush the bearings of the pump gears with the liquid whenever the pump gears are rotating and pumping the liquid.

A magnetically driven gear-pump head, comprising:

• a pump housing comprising a first plate and a second plate that define therebetween a pump cavity extending along a pump axis, the pump housing defining a pump inlet for delivering liquid into the pump housing and a pump outlet for delivering fluid from the pump housing;
• a magnet cup extending from the second plate and containing a driven magnet that is rotatable inside the magnet cup about the pump axis;
• a pump driving gear having a first gear axis and a pump driven gear having a second gear axis, the gear axes being parallel to but laterally offset a distance from the pump axis on first and second sides, respectively, of the pump axis, the pump gears being contained in the pump cavity, being journaled in respective bearings in the first and second plates, and being configured to interdigitate with each other such that rotation of the pump driving gear causes a corresponding contrarotation of the pump driven gear in the pump cavity;
• and
• a rotational coupling connecting the driven magnet to the pump driving gear in a manner such that rotation of the driven magnet about the pump axis causes corresponding rotation of the pump driving gear about the first gear axis, which causes corresponding contrarotation of the pump driven gear about the second gear axis in a manner by which liquid is pumped through the pump housing from the pump inlet to the pump outlet.

A gear pump, comprising:

• a magnetically driven gear-pump head comprising a pump housing having a pump axis and defining a pump cavity containing a pump driving gear and a pump driven gear;
• a pump inlet;
• a pump outlet;
• and a magnet cup extending along the pump axis and containing a driven magnet that is rotatable inside the magnet cup about the pump axis, the driven magnet comprising a first driving gear;
• the pump driving gear having a first gear axis and the pump driven gear having a second gear axis, the first gear axis being parallel to but laterally offset a distance from the pump axis on a first side of the pump axis, and the second gear axis being parallel to but laterally offset the distance from the pump axis on a second side of the pump axis, the pump gears being interdigitated with each other in the pump cavity such that rotation of the pump driving gear causes a corresponding contrarotation of the pump driven gear in the pump cavity;
• the pump driving gear comprising a second driving gear configured to interdigitate with the first driving gear such that rotation of the driven magnet causes, via the first and second driving gears, corresponding rotation of the pump driving gear and contrarotation of the pump driven gear in a manner by which liquid is pumped through the pump housing from the pump inlet to the pump outlet;
• and
• a prime mover situated and configured to cause rotation of the driven magnet.

A gear-pump head, comprising:

• pump-housing means having a pump axis and defining a pump cavity, a pump inlet, a pump outlet, and a magnet-enveloping means containing a driven magnet that is rotatable inside the magnet-enveloping means about the pump axis, the driven magnet comprising a rotational-coupling means;
• a pump driving gear having a first gear axis and a pump driven gear having a second gear axis, the first gear axis being parallel to but laterally offset from the pump axis on a first side of the pump axis, and the second gear axis being parallel to but laterally offset from the pump axis on a second side of the pump axis, the pump gears being situated in the pump cavity and being configured to interdigitate with each other such that rotation of the pump driving gear causes a corresponding contrarotation of the pump driven gear in the pump cavity;
• and
• offset-drive means coupling the driven magnet to the pump driving gear, such that rotation of the driven magnet about the pump axis causes corresponding rotation of the pump driving gear about the first gear axis, which causes a corresponding contrarotation of the pump driven gear about the second gear axis in a manner by which liquid is pumped through the pump-housing means from the pump inlet to the pump outlet.

In a gear-pump head comprising a pump housing having a pump axis and defining a pump cavity, a pump driving gear having a respective gear axis that is parallel to the pump axis, and a pump driven gear having a respective gear axis that is parallel to the pump axis, a method for driving the pump gears so as to cause liquid to flow through the pump cavity from an inlet to an outlet, the method comprising:

• disposing the pump gears in the pump cavity such that each of the respective gear axes is laterally offset from the pump axis on first and second sides, respectively, of the pump axis;
• disposing a driven magnet on the pump axis in a manner allowing the driven magnet to rotate about the pump axis;
• rotationally coupling the driven magnet to the pump driving gear such that rotation of the driven magnet about the pump axis causes corresponding rotation of the pump driving gear about its respective gear axis, which in turn causes contrarotation of the pump driven gear;
• and
• causing rotation of the driven magnet.