Abstract: A magnetic gripping apparatus, of the permanent magnet type, comprising a base plate and peripheral walls, at least a first and a second pole units, each pole unit comprising a main pole piece having an outer face defining a gripping surface, main permanent magnets arranged between said main pole pieces and said base plate, an intermediate pole member between said first and second pole units, said intermediate pole member extending from the base plate to the gripping surface and secondary magnets between the pole members and the pole pieces; a first electrical windings encircles each main magnet, said electrical winding being operatively conected to a control unit, and a residual flux eliminating circuit comprising a second electrical winding encircling said intermediate pole member, said second winding being operatively connected to a demagnetizing control unit.

Abstract: A magnetic gripping apparatus for gripping metal parts on machine tools, conveyor systems and the like. The apparatus comprises an external ferromagnetic yoke having a base plate and lateral walls; a first and at least a second pole unit, each unit comprising a main pole piece having an outer face defining a work-gripping surface parallel to said base plate; and an intermediate pole member between said first and second pole units, said pole member extending from the base plate to the gripping surface, and permanent magnets arranged at least between the main pole pieces, the base plate and an electric winding encirling the magnets between the main pole pieces and the base plate, said permanent magnets, in an activated condition of the apparatus, providing a pole distribution on the gripping surface in which said first and second pole units exhibit poles of opposite polarity on their outer faces.

Abstract: A magnetic anchoring apparatus, comprising in combination: an external ferromagnetic crown provided with a base plate and lateral walls; at least one group of four pole pieces defining pairs of corresponding poles of an anchoring surface, said pole pieces presenting their longitudinal axes at right angles to the base plate and in correspondence with the apexes of a square. The apparatus comprising moreover a plurality of permanent magnets for feeding the aforesaid poles, interposed between the pole pieces and, respectively, between the latter and said ferromagnetic crown.

Abstract: A magnetic work-holding device with at least two pole shoes defining a work surface, and a main magnetic core interposed between the two aforementioned shoes; the other sides of the pole shoes are fed by secondary magnetic elements whose poles facing the same pole shoe, have the same sign as the pole corresponding to the main magnetic core. A ferromagnetic yoke encircles the base and the sides of the equipment, short-circuiting the remaining poles of the secondary magnetic elements.

Abstract: The lifting device consists of an outer magnetic yoke and internal pole pieces forming an anchoring or working surface, with secondary permanent magnetic elements located between the yoke and the aforementioned pole pieces. There is also a reversible permanent magnetic element which may be rotated manually on a parallel axis to the said pole pieces, between an operative position in which its magnetic field is parallel to that of said secondary magnetic elements, and an inoperative position in which the magnetic field is short-circuited.

Abstract: Magnetic apparatus for securing ferromagnetic pieces to lifting equipment, conveying devices and machine tools. The apparatus comprises a first nonreversible magnetopermanent core; a second reversible magnetopermanent core coacting with the former on a same magnetic yoke defining part of the work securing surface, and a solenoid wound about said reversible core and supplied with direct current in either direction for a period of time sufficient to cause said reversible core to follow a portion of the hysterisis loop thereof to generate an electromagnetic field for inverting the polarization of said core, thus enabling respective activation or deactivation of the work securing surface.