Ngk Insulators, Inc.

Hiroyuki Kawase

Takeyuki Mizuno

Koji Kato

Kiyonori Kawasaki

Seiichi Asami

Kenji Adachi

Masahiro Fujiyama

A ceramic-metal composite joint body wherein a projection of a ceramic member is connected to a metal member, having a construction such that a ratio D between a circularity c of an outer portion of the projection and an outer diameter d of the projection: i.e., D=(c/d).times.100(%), is set to less than 0.03%. In this invention, since the ratio D=(c/d).times.100(%) is set to less than 0.03%, a stress concentration generated at a connection edge of the projection of the ceramic member can be reduced, and thus a ceramic-metal composite joint body having good reliability and durability can be obtained.

Ceramic-metal composite joint body

A machining method of a ceramic turbine rotor having a hub portion integrally formed with a plurality of radial blades, the hub portion having a front end to be centered during a finishing process of the radial blades and a rear end coaxially connected to a metallic support shaft, which machining method includes the steps of grinding the front distal end of said hub portion to form a tapered surface thereon; engaging the tapered surface of said hub portion with a corresponding tapered surface of an attachment mounted on a spindle of a headstock or a tailstock; and finishing the radial blades of said rotor in a desired form.

Machining method of ceramic turbine rotor

A ceramic turbo charger rotor having a blade portion including a shroud tip portion and a top portion, a back plate portion arranged rear of the blade portion, and a shaft portion arranged to the back plate portion is manufactured by working only a part of a back plate portion as a standard surface or by working only a top surface of the tip portion as a standard surface while no working is applied for the back plate portion, so as to reduce a total manufacturing cost.

Ceramic turbo charger rotor and method of manufacturing the same

A ceramic turbo charger rotor having a bearing structure in which an inner race of an angular ball bearing and a spacer are assembled to a journal shaft as one unit in such a manner that one end of the spacer is assembled to a turbine-side connecting portion of the journal shaft by a pressure inserting manner and the other end of the spacer is assembled to a compressor-side connecting portion of the journal shaft by a clearance fitting manner. Therefore, the deviation between a center axis and a rotational axis of the rotor caused by the pressure insertion of the spacer is released at the compressor side and the amount of the unbalance before correcting of the rotor is remarkably reduced.

Ceramic turbo charger rotor

In a method of manufacturing a ceramic turbo charger rotor, wherein an inner race of an angular ball bearing and a spacer are integrally secured to a journal portion of a metal shaft for connecting a ceramic turbine rotor and a metal compressor rotor, the inner race and the spacer are inserted to the journal portion of the metal shaft under a condition such that a tensile load is applied to the metal shaft.

Method of manufacturing ceramic turbo charger rotor

A ceramic-metal joined composite body including a ceramic member having a projection formed thereon, and a metallic member having a recess formed therein. The projection of the ceramic member is fitted into the recess of the metallic member, and a corner of a bottom of the recess has a rounded dimension such that R/D.gtoreq.0.04, in which R and D are the rounded dimension of the corner of the bottom of the recess and an outer diameter of the projection, respectively. The ceramic-metal joined composite body particularly is useful in a rotary shaft for a turbocharger rotor or a gas turbine rotor.

Growing community of inventors

Nagoya, Japan

Hiroyuki Kawase