Transmission component, method of manufacturing the same, and tapered roller bearing
AssigneeNtn Corporation
InventorsKouichi Okugami, Yoshinori Muramatsu, Chikara Ohki, Michio Hori
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Abstract
A transmission component is incorporated into a transmission in which an input shaft, an output shaft, or a gear is rotatably supported by a rolling bearing. The component has a nitriding layer at a surface layer and an austenite grain with a grain size number falling within a range exceeding 10. This provides a transmission component having an increased anti-crack strength, enhanced dimensional stability, and a long fatigue life. A method of manufacturing such a transmission component and a tapered roller bearing are also provided.
Claims15
A transmission component incorporated into a transmission capable of changing a rotational speed of an output shaft relative to a rotational speed of an input shaft by means of mesh of toothed wheels, said component having a nitriding layer at a surface layer, and an austenite grain with a grain size number falling within a range exceeding 10.
A transmission component incorporated into a transmission capable of changing a rotational speed of an output shaft relative to a rotational speed of an input shaft by means of mesh of toothed wheels, said component having a nitriding layer at a surface layer, and a fracture stress value of at least 2650 MPa.
A transmission component incorporated into a transmission capable of changing a rotational speed of an output shaft relative to a rotational speed of an input shaft by means of mesh of toothed wheels, said component having a nitriding layer at a surface layer, and a hydrogen content of at most 0.5 ppm.
A method of manufacturing a transmission component incorporated into a transmission capable of changing a rotational speed of an output shaft relative to a rotational speed of an input shaft by means of mesh of toothed wheels, wherein
- said component is formed at least by carbonitriding steel for a bearing's component at a temperature higher than an Al transformation point and then cooling the steel to a temperature lower than the Al transformation point and subsequently reheating the steel to a range of temperature of no less than the Al transformation point and less than said temperature applied to carbo-nitride the steel, and quenching the steel.
A tapered roller bearing having an inner ring, an outer ring, and a tapered roller, wherein at least any one of said inner ring, said outer ring and said tapered roller has a nitriding layer and an austenite grain with a grain size number falling within a range exceeding 10.
Dependencies are inferred from the claim text.