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AssigneeToyoda Koki Kabushiki Kaisha
InventorsMasaya Segi, Mikio Suzuki, Koichi Takanishi, Masaru Suzuki, Yoshinori Kaneda
Estimating the term…
An electromagnetic drive device for lineally reciprocatilvely moving an operating member like a spool of a spool valve is reduced in the manufacturing cost without being degraded in its operational performance. In the electromagnetic drive device, a stator body is excited by an electromagnetic coil to axially move a plunger guided in an inner bore of the stator body, against the resilient force of a spring. The stator body is constituted by arranging a plurality of core portion annular plate elements made of a magnetic material, a plurality of yoke portion annular plate elements made of a magnetic material and a plurality of non-magnetic portion annular plate elements made of a non-magnetic material and placed between the core portion annular plate elements and the yoke portion annular plate elements and by piling up and bodily joining these annular plate elements in axial alignment with one another. Each of the annular plate elements is provided with plural embossed portions each of which is half-blanked to be prominent at one surface side and hollow at the other surface side. The embossed portions formed on each annular plate element are fit at the prominent surface sides thereof respectively in the hollow surface sides of the embossed portions formed on another annular plate element, so that all the annular plate elements can be bodily joined in axial alignment with one another.
An electromagnetic drive device having a stator body composed of a core portion and a yoke portion serially arranged in axial alignment with a non-magnetic portion placed therebetween, a plunger slidably received in an inner bore formed in at least one of said yoke portion and said core portion in said stator body and resiliently urged in one direction, and an electromagnetic coil for exciting said stator body to move said plunger in the axial direction thereof against the resilient force, wherein said stator body is constituted by piling up in axial alignment and bodily joining a plurality of core portion annular plate elements made of a magnetic material to form said core portion, a plurality of yoke portion annular plate elements made of a magnetic material to form said yoke portion, and a plurality of non-magnetic portion annular plate elements made of a non-magnetic material to form said non-magnetic portion.
Dependencies are inferred from the claim text.