Magnetic specimen-transport system for automated clinical instrument

A magnetic transport system for transporting magnetically-attractive racks of specimen-containers along selected mutually perpendicular linear paths atop a non-magnetic support plate in a specimen-transport instrument, each of said magnetically-attractive specimen-container racks supporting a U-shaped ferromagnetic member having a pair of spaced leg portions, said magnetic transport system comprising:

• first and second independent, bi-directional, linear drive mechanisms, said first linear drive mechanism serving to support said second linear drive mechanism for movement along a first linear path and for selectively advancing said second linear drive mechanism along said first linear path in either direction, said second linear drive mechanism serving to support a magnetic field-producing device for movement along a second linear path extending perpendicular to said first linear path, said second linear path being closely spaced from a bottom side of said non-magnetic support plate, said second linear drive mechanism further serving to selectively advance said magnetic field-producing device in either direction along said second linear path, said magnetic field-producing device being effective to produce a magnetic field atop said non-magnetic support plate that is sufficiently strong to engage a magnetically-attractive specimen-container rack positioned atop said non-magnetic support plate and to advance said rack along said mutually perpendicular paths atop said non-magnetic support plate as said magnetic field-producing device is advanced along said second linear path, and as said second linear drive mechanism is advanced along said first linear path, said magnetic field-producing device comprising a permanent magnet supported by a platform, said permanent magnet having opposing poles that are spaced apart to magnetically engage said leg portions of said U-shaped ferromagnetic members.