Jtekt Corporation

Nippon Grease Co., Ltd.

Kensuke Suzuki

Wataru Yoshida

Toshiyuki Saito

Tsuyoshi Mikami

Kota Nanri

Nicolas Vincent Barbi

Hiroki Iwamatsu

Koji Yoshizaki

Masashi Mitsuoka

In a heat treatment method for obtaining a bearing ring for an annular roller bearing whose thickness changes in an axial direction, the heat treatment method includes (A) applying a quenching process to a work which is annular, made of high carbon chromium bearing steel, and having a thickness changing in an axial direction, (B) applying a tempering process to the work which is quenched to entirely soak the work in cooling liquid and inductively heat the work in a state that the work is soaked in the cooling liquid, and (C) applying a finishing process to the work which is tempered.

Heat treatment method and heat treatment device

An optical tweezers device includes: an acquisition unit which acquires basic movement information indicating a movement of a stage; a conversion unit which converts the movement of the stage indicated by the basic movement information into a movement of a particle being trapped and generates converted movement information indicating the movement of the particle; and a distance calculation unit which determines a distance between the particle being trapped by the laser beam and a focal point of the lens. The conversion unit generates the converted movement information by correcting the movement of the particle using the distance determined by the distance calculation unit.

Optical tweezers device

A bearing ring for a roller bearing includes: an inner layer part that is formed of tempering martensite or sorbite; and a surface layer part that surrounds the entire periphery of the inner layer part, in which Vickers hardness of a surface thereof is larger than that of the inner layer, and which is formed of tempering martensite. A raceway portion of the surface layer part a portion that is in contact with at least one end of the rolling contact surface of the roller in an axial direction, and includes a first raceway portion at which compressive residual stress of the raceway surface is relatively high.

Bearing ring for roller bearing, method for manufacturing the same, and roller bearing

An optical tweezers device determines trapping force data indicating a trapping force for a particle on the basis of a distance between the particle trapped by focusing laser beam with a lens and a focal point of the lens. The optical tweezers device determines a difference between a trapping force theoretical value that is estimated according to a linear relationship between the distance between the trapped particle and the focal point of the lens and the trapping force for the particle and the trapping force indicated by the trapping force data. The optical tweezers device controls a laser power of the light source on the basis of the difference of the trapping force.

A raceway of a roller bearing includes a first raceway whose raceway surface is under a relatively high compressive residual stress, and a second raceway whose raceway surface is under a compressive residual stress lower than the compressive residual stress applied to the raceway surface of the first raceway. The raceway surface of the second raceway has a Vickers hardness of 700 HV or more but less than 800 HV. The raceway surface of the first raceway includes a portion that is harder than the raceway surface of the second raceway and that is to be in contact with at least one of axial ends of a rolling contact surface of a roller. A rib includes a rib surface having a Vickers hardness of 450 HV or more but less than 550 HV.

Bearing ring for roller bearing, manufacturing method of bearing ring for roller bearing, and needle roller bearing

A grease composition which is excellent in seizure resistance can be provided without deteriorating resistance to stirring in the rolling device, and a rolling device in which the grease composition intervenes to a predetermined portion can be also provided by use of a grease composition comprising a base oil and a thickener, the thickener being a diurea compound obtained by allowing an amine mixture comprising alkylphenylamine, an alkyl group of which has 8 to 16 carbon atoms, and cyclohexylamine, to react with a diisocyanate compound, the amount of cyclohexylamine in the amine mixture being 80% by mole or more and less than 91% by mole, and a worked penetration being 300 to 330.

Growing community of inventors

Kashiwara, Japan

Kensuke Suzuki