Magnetic stirring system
First Claim
1. A magnetic stirrer comprising a bottle unit constituted by a closed culture bottle containing liquid and a gaseous headspace above the liquid, the bottle having a base and a stirrer bar of relatively low power magnetisation establishing opposite poles at opposite ends of the bar and extending parallel to the bottle base within the bottle, and a permanent magnet means of relatively high power providing spaced opposite poles in a plane parallel to the length of the stirrer bar located beneath the bottle base in close proximity thereto, and driving means for continuously rotating the permanent magnet means about an axis substantially normal to the bottle base so that its rotating strong magnetic field aligns with that of the stirrer bar and entrains the stirrer bar in continuous rotation in a plane parallel to and above the bottle base within the liquid in the container, thereby to disturb the liquid surface in order to promote gas exchange with the bottle headspace.
4 Assignments
0 Petitions
Accused Products
Abstract
A magnetic stirrer wherein a relatively weakly magnetised disposable stirrer bar inside a closed container, for example a stirrer bar moulded wholly of non-isotropic ferrite, is moved with a stirring action from outside the container by a relatively powerful magnetic driver, preferably consisting of a pair of permanent magnets of neodymium boron driven in rotation as an assembly.
45 Citations
9 Claims
- 1. A magnetic stirrer comprising a bottle unit constituted by a closed culture bottle containing liquid and a gaseous headspace above the liquid, the bottle having a base and a stirrer bar of relatively low power magnetisation establishing opposite poles at opposite ends of the bar and extending parallel to the bottle base within the bottle, and a permanent magnet means of relatively high power providing spaced opposite poles in a plane parallel to the length of the stirrer bar located beneath the bottle base in close proximity thereto, and driving means for continuously rotating the permanent magnet means about an axis substantially normal to the bottle base so that its rotating strong magnetic field aligns with that of the stirrer bar and entrains the stirrer bar in continuous rotation in a plane parallel to and above the bottle base within the liquid in the container, thereby to disturb the liquid surface in order to promote gas exchange with the bottle headspace.
- 8. A method of magnetically stirring a liquid within a closed culture bottle which contains a gaseous headspace above the liquid, wherein a stirrer bar of relatively low power magnetisation establishing opposite poles at opposite ends of the bar is inserted into the bottle to extend parallel to the bottle base, a permanent magnet means of relatively high power providing spaced opposite poles in a plane parallel to the length of the stirrer bar is continuously driven in rotation beneath the bottle base in close proximity thereto and about an axis substantially normal to the bottle base, causing its rotating strong magnetic field to align with that of the stirrer bar and thereby entrain the stirrer bar in continuous rotation in a plane parallel to and above the bottle base within the liquid in the container, thereby to disturb the liquid surface in order to promote gas exchange with the bottle head space.
Specification