An electromagnetic device is disclosed, the electromagnetic device comprising a core support having an exterior surface comprising at least one radial protrusion, a tubular magnetic core positioned around a portion of the length of the core support, the tubular magnetic core having an interior surface, at least one indent located in the interior surface of the tubular magnetic core, wherein the at least one protrusion is located within the at least one indent to prevent relative longitudinal movement between the core support and tubular magnetic core, and a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the tubular magnetic core.

Embodiments generally relate to linear variable displacement transformer (LVDT) position sensors. The position sensor comprises a bobbin, a moveable core, a primary coil of wire wound around the bobbin, and two secondary coils of wire wound around the bobbin about the primary coil using a fractional winding technique. For example, the winding length of the bobbin may be separated into three consecutive parts. Generally, the primary coil may be wound around the entire winding length of the bobbin. The first secondary coil may be wound around the first and second parts of the winding length. The second secondary coil may be wound around the second and third parts of the winding length. Additionally, the first secondary coil and the second secondary coil may overlap over the second part of the winding length.

In an embodiment, a coil component 10 has a drum core 20 housed in a through hole 32 of a ring core 30, and two types of securing parts are provided in a gap G between an outer circumference of one flange part 24 of the drum core 20 and an inner circumference of the through hole 32. Terminal electrodes 50A, 50B connecting to ends 46A, 46B pulled out from a winding wire 40 wound around the drum core 20 are assembled to the ring core 30. Second securing parts 60A, 60B are arranged to opposite to each other with respect to a center C of the flange part 24, and first securing parts 62A, 62B are provided to cover an outer side of the second securing parts 60A, 60B. A hardness of the second securing part is higher than that of the first securing part.

An arrangement comprising a linear variable differential transformer including a core displaceable in a bore surrounded by a coil arrangement including a primary coil and secondary coils in a displacement range including a linear response range of the linear variable differential transformer, wherein the bore at least extends between a first position at a first end of the coil arrangement and a second end at a second end of the coil arrangement, and wherein the arrangement comprises a control unit configured to produce output signals corresponding to a plurality of positions of the core in the bore when an excitation current is supplied to the primary coil.

An arrangement comprising a linear variable differential transformer including a core displaceable in a bore surrounded by a coil arrangement including a primary coil and secondary coils in a displacement range including a linear response range of the linear variable differential transformer, wherein the bore at least extends between a first position at a first end of the coil arrangement and a second end at a second end of the coil arrangement, and wherein the arrangement comprises a control unit configured to produce output signals corresponding to a plurality of positions of the core in the bore when an excitation current is supplied to the primary coil.

Apparatus and associated methods relate to a linear variable differential transformer (LVDT) probe including a plunger rod and a metal sheet formed into a cylinder with a C-shaped cross-section, configured to couple to the plunger rod. In an illustrative example, the coupling may be an interference fit aided by spring retention forces of the metal sheet. The metal sheet may be stamped, formed and applied to the plunger rod without annealing. One or more longitudinal metal sheet edges may be rounded. The C-shaped metal sheet may be welded to the plunger rod at a distal and/or proximal end. In some examples, the longitudinal edges of the metal sheet may be welded together and/or to the plunger rod. The ratio of relative electromagnetic permeability of the metal sheet to the plunger rod may be greater than 10. Various implementations may advantageously reduce lot-to-lot variability and reduce the cost of producing LVDTs.

Apparatus and associated methods relate to a linear variable differential transformer (LVDT) probe including a plunger rod and a metal sheet formed into a cylinder with a C-shaped cross-section, configured to couple to the plunger rod. In an illustrative example, the coupling may be an interference fit aided by spring retention forces of the metal sheet. The metal sheet may be stamped, formed and applied to the plunger rod without annealing. One or more longitudinal metal sheet edges may be rounded. The C-shaped metal sheet may be welded to the plunger rod at a distal and/or proximal end. In some examples, the longitudinal edges of the metal sheet may be welded together and/or to the plunger rod. The ratio of relative electromagnetic permeability of the metal sheet to the plunger rod may be greater than 10. Various implementations may advantageously reduce lot-to-lot variability and reduce the cost of producing LVDTs.

A linear variable differential transducer is disclosed comprising a tubular magnetic core formed from a sheet, a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the magnetic core.

A linear variable differential transducer is disclosed comprising a tubular magnetic core formed from a sheet, a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the magnetic core.

A coil arrangement for an inductive power transfer system comprising a core (32, 33) having a region of decreased permeability (34), a coil (45) associated with the core, and a tuning slug (35) which is moveable along an axis adjacent the region of decreased permeability in order to adjust the inductance of the coil arrangement, the tuning slug (35) having an effective permeability which varies along said axis.