The present invention intends to run one induction heating apparatus using a three-phase AC power supply without use of a Scott connection transformer while preventing an occurrence of a phase where no current flows. An induction heating system uses the three-phase AC power supply to run the induction heating apparatus including an induction heating coil, and has an intermediate apparatus including a coil that is wound on an iron core with an even number of turns, forming a closed magnetic circuit. Additionally, a winding start point of the induction heating coil is connected to the U phase of the three-phase AC power supply and a winding end point of the same is connected to a midpoint of the intermediate coil. The winding start point and end point of the intermediate coil are connected to the V and W phases of the three-phase AC power supply, respectively.

A deposition print head including a non-susceptive or low susceptive sleeve, a susceptive element having a filament channel, the susceptive element arranged inside the sleeve, wherein the susceptive element is susceptive for at least one of a magnetic field and an electrical field, wherein the filament channel is for feeding a thermoplastic filament in a feed direction. The deposition print head further includes an exciter arranged around the susceptive element, wherein the exciter is arranged for generating a field compatible with the susceptivity of the susceptive element, and a nozzle attached to one end of the susceptive element.

A deposition print head including a non-susceptive or low susceptive sleeve, a susceptive element having a filament channel, the susceptive element arranged inside the sleeve, wherein the susceptive element is susceptive for at least one of a magnetic field and an electrical field, wherein the filament channel is for feeding a thermoplastic filament in a feed direction. The deposition print head further includes an exciter arranged around the susceptive element, wherein the exciter is arranged for generating a field compatible with the susceptivity of the susceptive element, and a nozzle attached to one end of the susceptive element.

Fixtures and methods for induction heating of bored parts are described. The fixtures and methods may be used to counter the effects of convective heat transfer and thereby promote a more uniform temperature distribution around a bore of a bored part being heated. The fixture includes a base including one or more locators engaged with the part and locating the base relative to the part, and an induction heating coil supported by the base. The induction heating coil is disposed inside the bore of the part and is inductively coupled to the part. The induction heating coil is wound about a coil axis which is non-coaxial with a bore axis of the bore of the part during heating of the part.

Fixtures and methods for induction heating of bored parts are described. The fixtures and methods may be used to counter the effects of convective heat transfer and thereby promote a more uniform temperature distribution around a bore of a bored part being heated. The fixture includes a base including one or more locators engaged with the part and locating the base relative to the part, and an induction heating coil supported by the base. The induction heating coil is disposed inside the bore of the part and is inductively coupled to the part. The induction heating coil is wound about a coil axis which is non-coaxial with a bore axis of the bore of the part during heating of the part.

A portable heater for an annular bearing component includes an induction heater having a heating clamp connector and a main cable for the alimentation of the induction heater, a housing inside which is located the induction heater, the housing providing openings for the heating clamp connector and the main cable, a handle in order for an operator to grab the portable heater, and at least one pocket, a heating clamp intended to be stored into the pocket and intended to be connected to the heating clamp connector when in use.

The induction coil unit for heating a component that is rotationally symmetrical relative to an axis (7), in particular a tool holder (5), comprises a plurality of coils (19) arranged about the axis (7) of the tool holder (5) with pole elements, which are movable radially with respect to the axis (7), which are connected to one another by a common yoke ring (17). Upon excitation of the coils (19) with alternating current, the latter produce a magnetic flux running in the peripheral direction in the tool holder (5) for the inductive heating of the tool holder (5). The induction coil unit (1) can be moved in an oscillating manner by means of a drive (87) in the direction of the axis (7), the pole elements (21) moving in an oscillating manner along the tool holder (5). An induction coil unit of this type is in a position to heat a comparatively large region of the tool holder (5) despite a comparatively small energy requirement and comparatively small dimensions.

The induction coil unit for heating a component that is rotationally symmetrical relative to an axis (7), in particular a tool holder (5), comprises a plurality of coils (19) arranged about the axis (7) of the tool holder (5) with pole elements, which are movable radially with respect to the axis (7), which are connected to one another by a common yoke ring (17). Upon excitation of the coils (19) with alternating current, the latter produce a magnetic flux running in the peripheral direction in the tool holder (5) for the inductive heating of the tool holder (5). The induction coil unit (1) can be moved in an oscillating manner by means of a drive (87) in the direction of the axis (7), the pole elements (21) moving in an oscillating manner along the tool holder (5). An induction coil unit of this type is in a position to heat a comparatively large region of the tool holder (5) despite a comparatively small energy requirement and comparatively small dimensions.

A three-dimensional (3D) metal object manufacturing apparatus is equipped with a magnetic field generator to form a magnetic field selectively about a nozzle from which melted metal drops are ejected. The drops ejected in the presence of the magnetic field have their velocities reduced from the initial velocity at which they are ejected. The reduced velocity increases the time in flight of the drops before they impact their landing areas. The increased travel time enables the melted metal drops to oxidize sufficiently that they bond less tightly than the drops ejected without passing through the magnetic field. Thus, the apparatus can form metal support structures that adhere less tightly to the part portions of the object so they can be more easily removed after printing of the object.

An extruder for a metal material includes a cylinder having a receiving space in which a solid metal material is provided, a nozzle extending from a lower end of the cylinder, an upper coil provided on an outer surface of the cylinder and melting the solid metal material to form a liquid metal material, and a first lower coil provided on an outer surface of the nozzle to control an extruded shape of the liquid metal material.