PURPOSE: To produce a pulse gear having a high output characteristic with good production efficiency by subjecting a sintered molding obtd. by powder molding and sintering of magnetic material powder to size setting, then annealing the molding to restore magnetic permeability.
CONSTITUTION: The raw material powder consisting of the magnetic material is made into a pulse gear molding by a powder molding press. The above- mentioned molding is sintered to yield the sintered molding. The sintered molding 18 is housed into a packing space 16 delineated of a die 12 of a size setting device 10 and a central core 14 and is pushed down from above by an upper punch 20; in addition, the molding is compressed by a lower punch 22, by which the molding is subjected to the size setting. The sintered pulse gear molding after the size setting obtd. in the above-mentioned manner is annealed in a vacuum heating furnace (not shown). The annular pulse gear made of the sintered material provided with the tooth parts consisting of the magnetic material having the serration arrangement to generate a prescribed magnetic flux change in a rotating speed detecting sensor according to the revolutions of a shaft member such as axle hub when mounted to said member is thus obtd.
IMAHASHI KUNIHIKO
NAGAREI ICHIRO
OGINO KEIJI
ITO NORIO
