Abstract: A nuclear fusion reactor system includes a reactor core containing nuclear fusionable material and a plurality of conducting spheres arranged adjacent each other with at least two of said conducting spheres adjacent the reactor core. The reactor core and the conducting spheres form a electro/magnetic circuit such that fusion of fusionable material in the reactor core establishes an electro/magnetic flow around the electro/magnetic circuit. Preferably, a spherical electromagnetic confinement field is initiated around the reactor core such that fusion of the nuclear fusionable material generates a plasma which interacts with the spherical electromagnetic confinement field in a magnethydrodynamic manner. Preferably, electrical energy is inductively extracted in response to the electro/magnetic flow through a coil arrangement located around at least one of the conducting spheres.

Abstract: A system and method for increasing force density of a valve actuator particularly suited for use in actuation of intake and/or exhaust valves of an internal combustion engine include at least one electromagnet having a coil wound about a core, and an armature fixed to an armature shaft extending axially through the coil and the core, and axially movable relative thereto. The actuator includes a flux generator, such as at least one permanent magnet positioned between the coil and the armature, oriented so that magnetic flux of the generator travels in a direction opposite to magnetic flux produced by the coil through the core during coil energization to reduce saturation of the core, but in the same direction as the magnetic flux produced by the coil through the armature, to increase an attractive force between the armature and the electromagnet, resulting in an actuator with an increased force density.

Abstract: A pneumatically actuated magnetic workpiece holder comprising a housing having a contact surface for contacting a workpiece to be held, and a magnet assembly translationally disposed in the housing, the magnet assembly comprising a plurality of permanent magnets arranged so that adjacent magnets are of opposite polarities. The housing is adapted for fluid communication with a pneumatic supply. The magnet assembly is biased towards an operative position, according to which the magnet assembly is sufficiently near the contact surface to exert on a workpiece an attractive force sufficient for holding the workpiece in contact with the workpiece holder, and is translationally positionable by pneumatic pressure towards an inoperative position, according to which the magnet assembly is sufficiently distant from the contact surface so as to be unable to exert on the workpiece an attractive force sufficient for holding the workpiece in contact with the workpiece holder.

Abstract: A magnetic device includes a cylindrical outer pole having a central axis and formed of a ferromagnetic material including a circular base and a cylindrical sleeve defining an outwardly opening cylindrical cavity. A reversible magnetic unit located in said cavity includes a cylindrical core having a magnetic axis aligned with the central axis and a normal magnetic polarity in an inactive state. A cylindrical inner pole formed of a ferromagnetic material is operatively coupled to the core and inwardly radially spaced from said sleeve. An annular band between said sleeve and said inner pole formed of a permanent magnetic material has a magnetic polarity transverse to said central axis and magnetically aligned with said normal magnetic polarity of the core whereby an internal magnetic circuit is established in the inactive state through the poles, the core and the permanent magnet to the exclusion of said workpiece.

Abstract: The invention relates to a means for separating magnetic particles from a composition. The means comprises an elongated protective cover (1) that comprises a recess (2) extending from the upper end towards the lower end thereof, the recess comprising a movable magnetic rod (4), the proportion of the length of the rod to its thickness being at least about 2:1. The invention can be used in different applications especially in the fields of biotechnology, biochemistry, and biomedicine. Collecting particles by using the means is easy and fast.

Abstract: A magnetic lifting apparatus by using neodymium magnets, incorporating a plurality of polarity plates (10) disposed with a predetermined interval and having non-magnetic medium (11) in the longitudinal center; a plurality of interval members (20) disposed between the polarity plates (10); a top cover (30) covering the interval members (20) and the polarity plates (10), having a hook (31) on the upper side; a plurality of neodymium magnets (40) having S/N polarity in opposite and disposed between the polarity plates (10); a plurality of rotors (50) rotated with the neodymium magnets (40) being inserted therein; a switch handle (60) for switching polarity position of the rotor (50) and the neodymium magnets (40) engaged therewith to switchably generate magnetic attraction. The oxidation prevention means (70) includes a hollow space around the neodymium magnets (40) either vacuum or filled with an oxidation prevention liquid in order to prevent the neodymium magnets (40) from being in contact with oxygen.

Abstract: A manual magnetic anchoring device includes a monolithic ferromagnetic block, whereon a housing for stator magnets, a housing for a rotor core, a ferromagnetic crown for short circuiting of the magnetic flux during deactivation of the anchoring device, and at least a first and a second collector pole defining a working surface for anchoring a ferrous part are formed in one single piece.

Abstract: A holder device for workpieces in the form of even or flat metal sheets of a magnetically attractable material, which are to be welded together along a connecting path at edges thereof. The holder device forms a support face for the sheets to rest on. The support face is divided up into a plurality of face parts, which are respectively formed by a separate pole plate of magnetizable material. Each pole plate is provided with an independently magnetically activatable and de-activatable magnet apparatus, which is located underneath the respective pole plate on a support plate arrangement.

Abstract: An electromagnetic lock and status detection system and method therefor includes an armature, an electromagnet, and a status detection unit. The electromagnet is magnetically attracted to the armature into a mating relationship. A relatively high inductance is established in the electromagnet when the electromagnet is properly mated with the armature, and a relatively low inductance is established in the electromagnet when the electromagnet is not properly mated with armature. The status detection unit is coupled to the electromagnet to monitor the locking strength between the electromagnet and the armature. The unit monitors the locking strength by altering voltage level provided to the electromagnet and measuring the counter EMF induced in the electromagnet.

Abstract: The invention relates to a means for separating magnetic particles from a composition. The means comprises an elongated protective cover (1) that comprises a recess (2) extending from the upper end towards the lower end thereof, the recess comprising a movable magnetic rod (4), the proportion of the length of the rod to its thickness being at least about 2:1. The invention can be used in different applications especially in the fields of biotechnology, biochemistry, and biomedicine. Collecting particles by using the means is easy and fast.

Abstract: A magnetic lifting apparatus includes a plurality of magnetic substances, a plurality of rotor seat members, magnetic rotors, and permanent magnets alternately aligned with the plurality of magnetic substances. The apparatus includes stopping members for stopping rotation of magnetic rotors in a one way direction whereby upon lifting the operating member, the magnetic lifting apparatus either has a magnetic activity or no magnetic activity so as to attach to or release from an object, respectively.

Abstract: The invention relates to a method for separating magnetic particles from a composition in a vessel. In the method, particles are first concentrated on the wall of the vessel and collected from this area by using a separation means (1) to which the magnetic particles adhere. In this way, particles can be collected efficiently. The invention can be used in different applications especially in the fields of biotechnology, biochemistry, and biomedicine.

Abstract: Magnetic flux trapping clamps are provided that trap or pin the magnetic flux of ring shaped superconductive magnets in a high permeability metallic core located in the bore of the ring. Preferably, the superconductive magnets comprise a single crystal cut into a ring shape. Multiples of the flux-pinned magnets, having high magnetic strength, can be arranged in a variety of arrays for a range of applications. The devices offer several advantages over permanent or electromagnets. The devices easily activated by charging with a cryogenic fluid, to induce the superconductive effect, and deactivated by draining the fluid.

Abstract: The invention relates to a magnetic clamping device with a clamping body (1) comprising a cylinder plate (2) of non-magnetizable material provided with cylinders (5), a clamping plate (3) of non-magnetizable material situated at one side of the cylinder plate, a closing plate (4) situated at the other side of the cylinder plate, and pistons (9) made at least partly from magnetic material which are movable in the respective cylinders, which clamping body is further provided with channels (13, 14) to which a fluidic pressure source can be connected for the simultaneous movement of the pistons in the cylinders towards and away from the clamping plate. To improve the magnetic clamping action, all magnetic pistons (9) are fastened to a common piston plate (8). This ensures that all magnetic pistons, when energized, will exert their magnetic influence on the object to be clamped.

Abstract: A magnetic plate cylinder for a printing press includes an outer cylinder member having circumferentially and axially spaced plugs of magnetic material or axially spaced apart rings of magnetic material for directing a magnetic field in such a way as to hold a magnetic printing plate on the outer surface of the outer cylinder member. An inner cylinder member includes circumferentially and axially spaced permanent magnet members supported on a cylinder of nonmagnetic material or stacked circular ring magnets interposed between rings of magnetic or nonmagnetic material for generating a magnetic field passing through the plugs or rings of magnetic material on the outer cylinder member. The inner cylinder member is disposed to form a radial air gap between the outer cylinder member and an outer surface of the inner cylinder member.

Abstract: A magnetic lifting apparatus includes a plurality of magnetic substances, a plurality of pairs of first permanent magnets, a plurality of rotors having a pair of second permanent magnets, respectively, and an on/off switch handle connected to the rotors whereby upon rotating the on/off switch handle, the magnetic apparatus has a magnetic activity or not so as to attach to or release from the object.

Abstract: A magnetic grab has a pair of vertically elongated magnetic pole pieces each having an upper end and a lower end. The pole pieces diverge downward symmetrically with respect to a vertical symmetry plane with the upper ends substantially more closely spaced than the lower ends. A plurality of nonmagnetic elements fixed to the pole pieces secure same together and a generally cylindrical rotor engaged between the pole pieces and centered on and rotatable about a rotor axis extending horizontally parallel to and between the pole pieces is formed by a pair of soft-iron bodies one of which is substantially thicker in a direction transverse to the axis than the other. One or more permanent magnets are sandwiched between the bodies and polarized generally diametrically of the rotor axis.

Abstract: In the magnetic chuck disclosed herein, a pair of elongate pole members are arranged to provide magnetic contact with a workpiece along parallel lines and thus are somewhat in the nature of rails. Preferably, the ends of the poles are segmented and provide for height adjustment to accommodate workpieces which are not entirely flat. The pole members extend along the sides of an elongate base plate with a space therebetween. Interposed between each pole member and the base member is a relatively thin layer of permanent magnetic material which resists de-magnetation. A switchable permeable magnet is provided between the pole members above the base plate and this latter permanent magnet is surrounded by a coil which allows the polarity of its magnetism to be switched so that it either aids or opposes the thin magnetic layer in polarizing the pole ends.

Abstract: A magnetic chuck assembly comprises top and bottom plates separated by a layer of non-magnetizable material, each plate having magnetizable sections separated by strips of non-magnetic material. A rotor mounted between the top and bottom plates carries a plurality of permanent magnets substantially symmetrically disposed therein. The magnets in each half of the rotor are of the same polarity but those in one half are of opposite polarity to those in the other. When the rotor is turned to a position in which all the magnets of like polarity in one half thereof lie between the magnetizable sections of the plates on the same side of the non-magnetizable strips, the sections become magnetized and hold a magnetizable workpiece in place on the edges of the plate. Switching the rotor to a position in which equal numbers of magnets of opposite polarity lie between the magnetizable sections serves to de-energize the latter and release the workpiece.

Abstract: A magnetic grab has a pair of pole pieces each forming a downwardly directed pole and formed adjacent the respective poles with horizontally extending semicylindrical seats having approximately the same center of curvature and open concavely inward toward each other. One of the pieces has an upwardly directed upper surface to one side of the seats and the other piece has a lower surface directed downward at the upper surface and also to the one side of the seats. A rotor fitting in the seats is provided with a plurality of high-flux rotor magnets polarized about respective axes extending generally diametrically of the rotor axis. At least one low-flux permanent magnet having a vertical polarization axis between the upper and lower surfaces has its north pole engaging one of the surfaces and its south pole engaging the other surface.

Abstract: A new structure of permanent magnetic sucker comprising a base, a magnet conductive disk, a sucker, a support plate spring, an operating lever and a cam, in which the base is made of light-weight aluminum alloy to minimize its weight and load to working bench, the base is designed with two pads to facilitate use of large electromagnetic sucker, the operative lever is fixed through a sleeve to prevent from being seized, and characterized by the application of fusion weld at high temperature for assembly of the magnetic conductive disk and the sucker without any fixing pin or frame.

Abstract: The invention is directed to an electromagnetic holding device which includes one or more permanent magnets and an electromagnet. The holding device releases and pulls in units which are held thereon. During an exchange operation, the field of the electromagnet is superposable on the field of the permanent magnet either in the same direction or in the opposing direction and thereby intensifies or neutralizes the holding force. In order to provide the smallest possible assembly volume and lowest weight with the highest possible holding force, the permanent magnet is disposed ahead of the electromagnet when viewed with respect to the exchange face. When the exchange part is pulled in, the field lines of the electromagnet run in a completely closed flux-conducting part which is not interrupted at any location by an air gap.

Abstract: The invention is directed to a magazine for an apparatus such as a coordinate measuring apparatus. Measuring probes are held in their magazine locations by magnetic forces. Each magazine location is provided with one or more permanent magnets. The holding force of the permanent magnets is neutralized by an individual electromagnet on that magazine location which is involved in an exchange operation. In this way, the measuring probe being held can be easily removed. The magazine can also be for an apparatus such as a machine tool in which case work tools are held at the magazine locations.

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 holding device, comprising magnetically activable holding surface having pole members of different polarities, and at least a first and a second single-pole extension members for said pole members of opposite polarities. Each pole-extension member comprises a base portion fastened to a pole member and a movable portion sliding on said base portion along an inclined surface the sliding surfaces of said first and second pole-extension members are slanted in opposite angular directions in respect to said holding surface of the device.

Abstract: A rotatably adjustable two magnet door latch system is presented. Ferro magnetic latching means are normally coupled to the edge of a door stop. A multi-part door latch assembly is coupled to the edge of the door adjacent the stop when the door is closed.The assembly comprises a first thin magnet having a straight edge and an opposite concave edge. A second generally planar thin magnet has a first convex edge of radius equal to and fitting into the concave edge of the first magnet. Rotating means rotate the second magnet. Magnetic flux is a function of the length of arcs of the magnets that are adjacent. One or more flux plates transmit flux from the magnets to the stop and a housing modularizes the assembly for easy installation and protection against dirt.

Abstract: A method and apparatus for assembling magnetic serpentine coils on a magnetic sheet includes a carriage movable vertically and horizontally and supporting on its lower side a plurality of elongated electromagnets. Permanent magnets are arranged to have an upper surface engageable with the electromagnet and a lower surface having indentations to conform with the tubing. The movement of the carriage and the energization of the electromagnet are controlled so that the electromagnet is energized with a first polarity to attract the permanent magnet members and the serpentine tubing to lift the tubing from a predetermined position and, by movement of the carriage, pick up the tubing, transfer it horizontally to the sheet, and vertically deposit it on the sheet. The electromagnets are then reversed in polarity to cause the permanent magnets to separate from the electromagnets and clamp the tubing on the sheet so that the tubing can be fastened by other methods.

Abstract: Longitudinal and transverse rows of pole pieces are flanked by pairs of rows of fixed permanent magnets in one direction and by movable permanent magnets in another direction and are mounted on a magnetic or nonmagnetic base plate. An actuating mechanism for the movable permanent magnets enables the displacement thereof by one pole pitch so that in one position all four sides of each pole piece are flanked by magnetic poles of the same polarity so that the flux lines close through the active face of the magnetic retention plate. In the other position, pairs of permanent magnets confronting the opposite sides of the pole pieces are of opposite polarity so that flux line closure is entirely within the body of the plate.

Abstract: The magnetic chuck disclosed herein is of the permanent magnet type in which both a top plate and a shiftable pack comprise alternating major pole pieces and magnets, the pack being shiftable so that its magnets either aid or oppose the magnets in the top plate, thereby to change between holding and release states. Improved holding for thin workpieces is obtained by providing a central region in the top plate in which the major pole pieces are thinner than the magnets and in which a plurality of floating minor pole pieces are positioned in the gaps between the major poles. While less flux is available through the thinner major pole pieces, the floating pole pieces provide an increased number of transitions for flux between top plate and workpiece so the total holding force for thin workpieces is improved.

Abstract: A magnetic holding device to be mounted to a magnetizable surface. It includes a body and a magnet having a pair of poles. A first and a second pole piece are mounted to the body adjacent to the magnet, each forming a continuation of a respective one of the poles. Each pole piece is a plurality of elongated magnetizable members in side to side sliding relationship to one another. They project from the body, and their projection is adjustable and selectable by sliding them. Releasable compression means allows for their relative movement when released, and holds them in an adjusted position when set. As optional features, the pole pieces can be magnetized or not, such as by the use an electromagnet or rotatable magnet, and the compression means may be a cam.

Abstract: The invention concerns a receiver (1) in the probe head of a multiple-coordinate measuring machine in which probe-pin combinations (21) can be replaceably chucked with high precision with respect to their position in space. The receiver contains an isostatic three-point support (14) against which the base (15, 16, 17, 18, 19) of the probe-pin combination is drawn by an electrically operated clamping device. The clamping device is coupled with the control computer of the measuring machine so that a probe change can be effected automatically.In a preferred embodiment, the clamping device consists of a permanent magnet (11) and of an electromagnet (10) by which the field of the permanent magnet (11) can be selectively counteracted or increased to achieve pick-up and release functions. In another embodiment, a motor-driven screw thread performs the pick-up and release functions, and assures that the picked-up probe will unambiguously be drawn into correct isostatic engagement with the three-point support.

Abstract: Magnetic device for withdrawing magnetic gel beads or the like from a biological fluid and transferring them to an immunoenzymatic assay medium. This device includes a housing of insulating material, particularly of plastic material, into which is inserted a magnet and over the height of which is formed a traversing orifice in which is housed a rod formed of a lower portion of magnetizable material and an upper portion of non-magnetizable material on which is mounted a return spring, between a stop washer fixed in the vicinity of the upper end of the rod and the upper surface of the housing. The device can advantageously be included in a ready-for-use kit for carrying out immunoenzymatic assays.

Abstract: The invention concerns a receiver (1) in the probe head of a multiple-coordinate measuring machine in which probe-pin combinations (21) can be replaceably chucked with high precision with respect to their position in space. The receiver contains an isostatic three-point support (14) against which the base (15, 16, 17, 18, 19) of the probe-pin combination is drawn by an electrically operated clamping device. The clamping device is coupled with the control computer of the measuring machine so that a probe change can be effected automatically.In a preferred embodiment, the clamping device consists of a permanent magnet (11) and of an electromagnet (10) by which the field of the permanent magnet (11) can be selectively counteracted or increased to achieve pick-up and release functions. In another embodiment, a motor-driven screw thread performs the pick-up and release functions, and assures that the picked-up probe will unambiguously be drawn into correct isostatic engagement with the three-point support.

Abstract: According to the present invention there is provided a magnetic retainer assembly adapted for selective attachment to and detachment from a magnetic object, which assembly comprises: a plurality of permanent magnet members of a uniform shape and size arranged regularly in a predetermined set of positions in the assembly for individually producing magnetic fields of a uniform field strength; support means in the assembly for holding the permanent magnet members securely therein and positioning said members spaced apart from one another in an essentially magnetically insulating relationship; and magnetic path-forming means in the support member for providing a magnetic path for each of the permanent magnet members to be magnetically conducted with the magnetizable object, thereby magnetically securing the assembly to the object.

Abstract: A plastic hollow body contains a resilient spring plate. The spring plate is attached to the body at one end and, at another end, has an iron core. A hole in the body is slightly offset from a hole in the spring plate such that a pin extending through the hole in the body cannot pass through the hole in the spring plate until the spring plate is bent by a force from the spring. The pin then extends through the hole in the spring plate and the spring plate is locked onto a reduced diameter portion of the pin. The release of the pin is possible only by applying a magnet adjacent the iron core so as to move the spring plate from the locked position.

Abstract: A permanent magnetic chuck in which a workpiece holding plate comprises a plurality of permanent magnets each with a magnetic isolator which are alternatively laminated, said magnetic pole pieces and said magnetic isolator are respectively constructed as layers of a plurality of thin magnetic layers and a plurality of thin non-magnetic layers each of which is disposed alternately with each of said magnetic layers; and a sliding magnet member which comprises a plurality of disk-shaped permanent magnets disposed in round holes provided in said member at the same pitch as the lamination pitch of the workpiece holding plate is disposed. The permanent magnets of the workpiece holding plate are so disposed that the same magnetic poles of the adjacent magnets are opposed to each other. The permanent magnets of the sliding magnet member are so disposed that the magnetic lines of flux pass vertically and that the opposite magnetic poles of the adjacent permanent magnets are opposed to each other.

Abstract: A permanent magnet with a split magnetic flux conductor between the pole shoes serves to attract a magnetizable load to the pole shoes of an electromagnet whose pole shoes constitute extensions of the pole shoes of the permanent magnet and whose split magnetic flux conductor extends between the respective pole shoes in parallel with the other conductor. An armature is movable into the gap between the parts of the magnetic flux conductor of the permanent magnet or between the parts of the magnetic conductor of the electromagnet by a fluid-operated motor or by the application of d-c current of proper polarity to the exciting coils of the electromagnet. The permanent magnet ceases to attract the load to the pole shoes of the electromagnet when the armature is moved into the gap between the portions of the magnetic flux conductor of the electromagnet.

Abstract: A magnetic chuck designed as a releasable holder for ferromagnetic workpieces comprises an orthogonal matrix of flat permeable pole pieces rising above a ferromagnetic base plate, the pole pieces forming rows parallel to their major faces and columns perpendicular thereto; the pole pieces of the two outermost rows contact the base while the other pole pieces are separated from the base by a nonpermeable layer. The rows of pole pieces alternate with rows of flat permanent magnets which follow one another with the same pitch as the pole pieces and are magnetized in the transverse direction with alternating polarity in each row. The magnets of every other row are fixedly aligned with the pole pieces of their columns while those of the remaining rows are longitudinally shiftable by one pitch to establish either a working position, with like magnet poles confronting each other across an intervening pole piece, or an inoperative position in which the magnet poles alternate within each column.

Abstract: Described is a novel method and associated fixture for magnetically attracting and holding back-bar means to respective magnetic core-leg portions of a typical magnetic slider assembly.

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 chuck for use in grinding optical lenses consisting of a means for increasing or decreasing the magnetic force exerted by a magnetic attachment surface contained in a housing sized for use in a lens grinding machine, wherein the means for increasing or decreasing the magnetic force exerted by the magnetic attachment surface is operated by means of manually operating a control to rotate a permanent magnet 90 degrees from a first position to a second position, where in the first position the magnetic force exerted by the magnetic attachment surface is minimal and in the second position, a substantial increase of magnetic force is exerted by the magnetic attachment surface for secured attachment of the lens piece during grinding of a raw glass lens blank into an optical lens.

Abstract: A switchable permanent magnetic chuck including a housing which has one open end and a face plate which covers the open end of the housing. The face plate comprises a plurality of elongated magnetic pole members and a plurality of elongated non-magnetic members, both members being arranged in an alternately juxtaposed manner. The permanent magnetic chuck further included a plurality of first permanent magnets each disposed between adjacent magnetic pole members of the face plate so as to give alternately inverted magnetized directions in the transverse direction of the magnetic pole members. In the housing is enclosed a movable member which is movable in the transverse direction of the magnetic pole members, and on the movable member are disposed a plurality of second permanent magnets in a corresponding relation to the magnetic pole members.

Abstract: A switchable permanent magnetic chuck of the type capable of detachably hold a magnetic work piece. The chuck comprises a frame structure with its top and bottom being open, a work supporting faceplate and a bottom plate to cover the top and bottom openings, respectively, of the frame structure, a plurality of stationary permanent magnets supported on the frame structure and a plurality of movable permanent magnets supported on a shiftable plate which is movably accomodated in the frame structure, and adapted to be operable in association with the stationary permanent magnets to bring the work supporting faceplate into a magnetized or demagnetized condition. In order to reduce the height of the chuck without reducing the magnetic power, permanent magnets having a high coercive force are used as the above-mentioned stationary and movable permanent magnets.

Abstract: A magnetic holder has a permanent magnet stator and a permanent magnet rotor, the magnetic mass of the latter being greater than that of the form and a play defining an air gap being provided between them so that the losses in the air gap compensate for the magnetic mass by which the rotor permanent magnet exceeds the stator permanent magnet.

Abstract: A permanent magnet energized holding device for holding of, or onto, ferromagnetic objects and readily switchable between "on" and "off" positions, has outer and inner cup-shaped pole shoe members of good magnetically conductive material concentrically nested in spaced apart relation one inside the other with their rim edges or pole faces lying in a common plane. A ring-shaped stationary permanent magnet is fixed in the space between the peripheral side walls of the cup members, and the cup members and stationary magnet are correspondingly divided magnetically into two portions at the same points therearound by non-magnetic mediums. A rotatable permanent magnet sandwiched between the base end walls of the cup members is rotatable therebetween by an operating shaft or other actuating means to switch the holding device between its "on" and "off" positions. The two magnets are magnetized in the direction of their smallest dimension or thickness, with portions of each having opposite magnetic polarity.

Abstract: A switchable magnetic chuck has a magnet assembly slidably arranged in a casing to magnetize and demagnetize a top plate disposed in an open side of the casing. The top plate is provided with main pole members and auxiliary pole members which are arranged alternatively in the sliding direction of the magnet assembly, separated respectively by a non-magnetic separator disposed between them. To smoothen the change-over operation, enhance magnetic force under the magnetized condition and reduce residual attraction under the demagnetized condition, each main pole member is formed on the side facing the magnet assembly with an extension extending between the auxiliary pole member adjacent thereto and the magnet assembly.

Abstract: A magnetic chuck or holder for workpieces adapted to be mounted on a worktable of a machine tool comprises a stack of alternating permanent magnets and magnetically conducting plates having a central passage through the stack in which a second stack of magnets and magnetically conductive plates is received for longitudinal movement, e.g. by a crank or an eccentric drive cooperating with one end of the second step. The two stacks are so arranged that they magnetically cancel the magnetic field lines on the upper, lateral and bottom surfaces of the chuck in one position of the second stack but create such field lines in a second position that all surfaces of the upper, lower and lateral surfaces are magnetically effective. This allows switching of the chuck to an effective state so that a workpiece is affixed magnetically to the upper surface of either or both lateral surfaces, and at the same time the chuck is magnetically fixed on the worktable of the machine tool.

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: A magnetic decoupler for use with an antitheft device is disclosed. In one preferred embodiment, the decoupler includes a composite permanent magnet comprising an annular permanent magnet that may be of ceramic and a second, preferably disc-shaped permanent magnet, which is preferably more strongly magnetized than the annular magnet and which preferably comprises a rare earth element. The two magnets are coaxially aligned with but axially displaced from each other and are oriented with the opposite polarity so as to create a region of especially great magnetic flux in the bore of the annular magnet. A cover plate, preferably of cold-rolled steel, may be provided adjacent the face of the annular magnet that is remote from the second magnet to further concentrate the flux in the bore.

Abstract: A permanent magnet-type lifting device for lifting heavy steel articles or the like in which a magnetic assembly of ferrite magnets stacked to form a single unit between pole pieces of a magnetically permeable material is rotatably disposed between plural magnetic member magnetically isolated from one another. In a preferred embodiment, plural rotated assemblies are provided and are mechanically linked through a common rotation mechanism. The magnetic member have an attracting surface and an inclined portion extending toward the attracting portion.