A plurality of chip evacuating grooves (16, 26, 36, 46a, 46b) in a vertical direction in parallel with a rotational axis of a core main body (14) are formed at an outer peripheral face of the core main body (14) in a circumferential direction from a lower end portion to an upper end portion of the core main body (14) in a cylindrical shape provided with a drilling blade (15) at a lower end edge thereof. Further, a sectional area of the chip evacuating groove (16) is formed to gradually increase ...

A magnetic core obtained by laminating or winding a magnetic material ribbon and an electrical insulating material wherein the magnetic core has the relationship of 0.5 a.ltoreq.b<a in which the width of the magnetic material ribbon is "a", and the width of the electrical insulating material is "b".

A tire cord which is improved in rubber penetration. The cord has at least four filaments twisted together so as to form a core and a sheath surrounding the core. The filaments change place repeatedly along the longitudinal direction of the cord such that one of the filaments forms the core in a portion, but in a different portion of the cord, the same filament forms part of the sheath.

An expandable mandrel including a threaded spindle with a drive for rotating the spindle, wedge pieces supported on the spindle with core chuck lugs facing outwardly for engaging the inner surface of a core, the wedge pieces having outwardly facing inclined cam surfaces, matching cam surfaces on the core chuck lugs to expand the core chuck lugs when the wedge pieces are moved relatively axially by the spindle, the wedge pieces and core chuck lugs being free to rotate with the spindle until locke...

A tubular core for carrying yarn wound therearound to define a bobbin for a textile machine, and method of making such core are provided, wherein the core has a load-carrying structure and an inside portion which is adapted to be engaged by a carrier shaft to provide substantially frictional holding of the core and bobbin on the shaft and wherein such inside portion comprises a sleeve made of a yieldable resilient polymeric material which is adapted to be yieldingly compressed between the struct...

The new structure of a ferrite core for the use of a power transformer and/or a choke coil has been found. The core is assembled by a pair of identical core halves, and each of core half comprises (a) a circular center boss(12), (b) a pair of outer walls(14,16) positioned at both the sides of said boss(12) so that a fan-shaped empty space is provided between the circular boss(12) and a pair of outer walls(14,16) for mounting a coil, (c) a pair of base plates(18,20) coupling said boss(12) with sa...

The new structure of a ferrite core for the use of a power transformer and/or a choke coil has been found. The core is assembled by a pair of identical core halves, and each core half comprises (a) a circular center boss (6), (b) a pair of outer walls (7, 8) positioned at both the sides of said boss for mounting a coil, (c) a pair of base plates (9, 10) coupling said center boss and said outer walls, (d) each of the outer walls being substantially rectangular with an external linear wall and an ...

A rolled core is formed by winding a thin body of an amorphous magnetic alloy having positive magnetostriction characteristics so that, of the two surfaces the surface of smaller surface coarseness faces inward. This rolled core is improved in iron loss over a rolled core obtained by winding the thin body so that the surface of greater surface coarseness faces inward. Breakage of the thin body tends to occur less frequently when it is wound so that the surface faces inward.

A hydrostatic working device for taking samples from the bottom of the sea. The working device has an outer tube (1), the cylinder tube (1), the cylinder tube with lead-through (5 and 7), and an inner tube (2), the sampling tube with a piston, whereby the space between the outer tube (1) and the inner tube (2), with the piston at the upper end, constitutes a low pressure chamber (29) filled by air under a moderate pressure, in order to keep the sampling tube (2) in an upper position until the va...

A core chuck has a generally spool-shaped mandrel with an outer surface configured to define three longitudinally extending lobes. A set of three or more arcuate friction plates surround the lobular outer surface of the mandrel and are movably held in place with elastic bands. Each friction plate has an inner surface contoured to conform to the shape of a corresponding lobe of the mandrel and an outer surface for frictionally engaging the inside surface of a core. The outer surfaces of the frict...