Patents by Inventor Kazumasa SEKO
Kazumasa SEKO has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20240003338Abstract: A roller bearing includes: inner and outer rings; rollers interposed between raceway surfaces of the inner and outer rings and having a roller outer circumferential surface; a cage retaining the rollers; and a DLC film on the roller outer circumferential surface. The DLC film includes a superficial layer having cavities provided therein to hold a lubricating agent. The rollers have a ratio of surface area occupied by the cavities of 40% or less, and the cavities have a size of 10 to 100 ?m when viewed in a plan view thereof. The DLC film can have a multilayered structure in which the superficial layer is layered on an additional layer, and the cavities can include a void of soft DLC present in the superficial layer and having a film hardness lower than that of the additional layer.Type: ApplicationFiled: September 19, 2023Publication date: January 4, 2024Applicant: NTN CORPORATIONInventors: Yuusaku KIBA, Kazumasa SEKO, Michio HORI, Koji MIYAKE, Yoshikazu TANAKA
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Publication number: 20240003386Abstract: Provided is a roller bearing which includes rollers (4, 5) interposed between raceway surfaces of inner and outer rings (2, 3) and having a roller outer circumferential surface, and a DLC film on the roller outer circumferential surface. The DLC film includes a metal layer, an intermediate layer containing the metal and DLC, and a superficial layer containing DLC, in the stated order starting from a side adjacent to a substrate of the rollers (4, 5). The intermediate layer has a bilayered structure of a top layer and a bottom layer. The top layer is a DLC-enriched layer having a greater content of DLC than the bottom layer. The bottom layer is a metal-enriched layer having a greater content of the metal than the top layer. The metal-enriched layer has a layer thickness of between at least 100 nm and no more than 300 nm.Type: ApplicationFiled: September 19, 2023Publication date: January 4, 2024Applicant: NTN CORPORATIONInventors: Yuusaku KIBA, Kazumasa SEKO, Michio HORI, Koji MIYAKE, Yoshikazu TANAKA
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Patent number: 11773901Abstract: Provided is a self-aligning roller bearing for supporting a main shaft of a wind power generator, the self-aligning roller bearing including an inner ring, an outer ring, two rows of rollers, and retainers. Each of the rollers has an outer peripheral surface formed with a DLC coating having a multilayer structure. The DLC coating has a film thickness of 2.0 ?m or larger. A base material of each of the rollers has an external surface having a surface roughness of Ra?0.3 and R?q?0.05. The DLC coating having the multilayer structure includes layers having stepwisely increasing film hardnesses such that a layer situated closer to outside has a higher hardness.Type: GrantFiled: September 27, 2021Date of Patent: October 3, 2023Assignee: NTN CORPORATIONInventors: Kazumasa Seko, Masaki Nakanishi, Takashi Yamamoto
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Patent number: 11306776Abstract: Provided is a double-row self-aligning roller bearing including: an inner ring; an outer ring having a spherical raceway surface; and rollers arranged in two rows and interposed between the inner ring and the outer ring, wherein a ratio of a contact angle ?1 in one row to a contact angle ?2 in the other row falls within a range of 0.25??1/?2?0.5, and a ratio of distance B1 in a bearing width direction from an end face of the bearing on a side of the one of the rows to an intersection of two lines of action defining the contact angles of the two rows, relative to a distance B2 in the bearing width direction from an end face of the bearing on a side of the other of the rows to the intersection falls within a range of 0.5?B1/B2?0.6.Type: GrantFiled: October 15, 2020Date of Patent: April 19, 2022Assignee: NTN CORPORATIONInventors: Kazumasa Seko, Michio Hori, Yasuyuki Inoue, Takashi Yamamoto, Masaki Nakanishi
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Publication number: 20220010836Abstract: Provided is a self-aligning roller bearing for supporting a main shaft of a wind power generator, the self-aligning roller bearing including an inner ring, an outer ring, two rows of rollers, and retainers. Each of the rollers has an outer peripheral surface formed with a DLC coating having a multilayer structure. The DLC coating has a film thickness of 2.0 ?m or larger. A base material of each of the rollers has an external surface having a surface roughness of Ra?0.3 and R?q?0.05. The DLC coating having the multilayer structure includes layers having stepwisely increasing film hardnesses such that a layer situated closer to outside has a higher hardness.Type: ApplicationFiled: September 27, 2021Publication date: January 13, 2022Applicant: NTN CORPORATIONInventors: Kazumasa SEKO, Masaki NAKANISHI, Takashi YAMAMOTO
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Patent number: 11187266Abstract: The double-row self-aligning roller bearing includes an outer ring having a spherical raceway surface, and each of rollers in two rows has an outer peripheral surface whose cross-sectional shape corresponds to the raceway surface of the outer ring. The rollers in the two rows have different lengths from each other, and the length of the longer rollers is equal to or greater than 36% of a bearing width. A ratio of a contact angle of the shorter rollers relative to a contact angle of the longer rollers is within a range of 1:4 to 1:2. The contact angle of the shorter rollers has a range of 3° to 5°, and the contact angle of the longer rollers has a range of 11° to 14°.Type: GrantFiled: January 23, 2020Date of Patent: November 30, 2021Assignee: NTN CORPORATIONInventors: Kazumasa Seko, Yasuyuki Inoue, Takashi Yamamoto, Michio Hori
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Publication number: 20210025448Abstract: Provided is a double-row self-aligning roller bearing including: an inner ring; an outer ring having a spherical raceway surface; and rollers arranged in two rows and interposed between the inner ring and the outer ring, wherein a ratio of a contact angle ?1 in one row to a contact angle ?2 in the other row falls within a range of 0.25??1/?2?0.5, and a ratio of distance B1 in a bearing width direction from an end face of the bearing on a side of the one of the rows to an intersection of two lines of action defining the contact angles of the two rows, relative to a distance B2 in the bearing width direction from an end face of the bearing on a side of the other of the rows to the intersection falls within a range of 0.5?B1/B2?0.6.Type: ApplicationFiled: October 15, 2020Publication date: January 28, 2021Applicant: NTN CORPORATIONInventors: Kazumasa SEKO, Michio HORI, Yasuyuki INOUE, Takashi YAMAMOTO, Masaki NAKANISHI
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Patent number: 10883544Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. Either or both of shapes and contact angles of the rollers are different from each other. An attachment hole to which a protrusion prevention jig is attachable is provided in an end surface of at least either one of the inner ring and the outer ring. The protrusion prevention jig prevents protrusion of the end surface of the inner ring in the bearing width direction with respect to the end surface of the outer ring.Type: GrantFiled: July 10, 2019Date of Patent: January 5, 2021Assignee: NTN CORPORATIONInventors: Kazumasa Seko, Takashi Yamamoto, Yasuyuki Inoue, Michio Hori
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Patent number: 10808761Abstract: A rolling bearing includes an inner ring, an outer ring, and rolling elements interposed between the inner ring and the outer ring. A surface layer portion, beneath a raceway surface (10a), of a base material of a raceway ring (10) which is the inner ring or the outer ring, is a wear-resistant layer (13) which has a higher hardness than a residual portion (12), beneath the surface layer portion, of the base material, and includes a minute-recess-and-projection surface. An oxide film (14) is provided which has such a film thickness (t) as to fill recesses of the minute-recess-and-projection surface of the wear-resistant layer (13), and includes recesses and projections existing along the minute-recess-and-projection surface, and the oxide film (14) coats the surface of the wear-resistant layer (13). The oxide film (14) is made from a material more fragile than the wear-resistant layer (13) of the base material.Type: GrantFiled: March 22, 2017Date of Patent: October 20, 2020Assignee: NTN CORPORATIONInventors: Weida Yan, Kazumasa Seko, Michio Hori, Takashi Yamamoto, Naoya Hasegawa
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Patent number: 10697492Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. The rollers have lengths equal to each other and maximum diameters equal to each other, and have different distances from centers of the roller lengths to positions at which the maximum diameters are obtained.Type: GrantFiled: July 10, 2019Date of Patent: June 30, 2020Assignee: NTN CORPORATIONInventors: Takashi Yamamoto, Yasuyuki Inoue, Kazumasa Seko, Michio Hori
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Publication number: 20200158168Abstract: The double-row self-aligning roller bearing includes an outer ring having a spherical raceway surface, and each of rollers in two rows has an outer peripheral surface whose cross-sectional shape corresponds to the raceway surface of the outer ring. The rollers in the two rows have different lengths from each other, and the length of the longer rollers is equal to or greater than 36% of a bearing width. A ratio of a contact angle of the shorter rollers relative to a contact angle of the longer rollers is within a range of 1:4 to 1:2. The contact angle of the shorter rollers has a range of 3° to 5°, and the contact angle of the longer rollers has a range of 11° to 14°.Type: ApplicationFiled: January 23, 2020Publication date: May 21, 2020Applicant: NTN CORPORATIONInventors: Kazumasa SEKO, Yasuyuki INOUE, Takashi YAMAMOTO, Michio HORI
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Patent number: 10655674Abstract: A double-row self-aligning roller bearing, which is suitable for receiving an axial load and a radial load, and loads having different magnitudes acting on rollers in two rows, and achieves sufficient load capacity for the rollers that receive axial load within the constraint of dimensional standards, is provided. The double-row self-aligning roller bearing includes inner and outer rings; and rollers in two rows arranged in a bearing width direction interposed between the inner and outer rings and having lengths different from each other. The roller has an outer peripheral surface of a cross-sectional shape along a raceway surface of the outer ring having a spherical shape. Length of the longer rollers is equal to or greater than 39% of the bearing width. A ratio of contact angle of the shorter rollers and contact angle of the longer rollers is within a range of 1:4 to 1:2.Type: GrantFiled: September 21, 2018Date of Patent: May 19, 2020Assignee: NTN CORPORATIONInventors: Takashi Yamamoto, Kazumasa Seko, Yasuyuki Inoue, Michio Hori
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Publication number: 20190331164Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. The rollers have lengths equal to each other and maximum diameters equal to each other, and have different distances from centers of the roller lengths to positions at which the maximum diameters are obtained.Type: ApplicationFiled: July 10, 2019Publication date: October 31, 2019Applicant: NTN CORPORATIONInventors: Takashi YAMAMOTO, Yasuyuki Inoue, Kazumasa Seko, Michio Hori
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Publication number: 20190331165Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. Either or both of shapes and contact angles of the rollers are different from each other. An attachment hole to which a protrusion prevention jig is attachable is provided in an end surface of at least either one of the inner ring and the outer ring. The protrusion prevention jig prevents protrusion of the end surface of the inner ring in the bearing width direction with respect to the end surface of the outer ring.Type: ApplicationFiled: July 10, 2019Publication date: October 31, 2019Applicant: NTN CORPORATIONInventors: Kazumasa SEKO, Takashi Yamamoto, Yasuyuki Inoue, Michio Hori
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Publication number: 20190113078Abstract: A rolling bearing includes an inner ring, an outer ring, and rolling elements interposed between the inner ring and the outer ring. A surface layer portion, beneath a raceway surface (10a), of a base material of a raceway ring (10) which is the inner ring or the outer ring, is a wear-resistant layer (13) which has a higher hardness than a residual portion (12), beneath the surface layer portion, of the base material, and includes a minute-recess-and-projection surface. An oxide film (14) is provided which has such a film thickness (t) as to fill recesses of the minute-recess-and-projection surface of the wear-resistant layer (13), and includes recesses and projections existing along the minute-recess-and-projection surface, and the oxide film (14) coats the surface of the wear-resistant layer (13). The oxide film (14) is made from a material more fragile than the wear-resistant layer (13) of the base material.Type: ApplicationFiled: March 22, 2017Publication date: April 18, 2019Applicant: NTN CORPORATIONInventors: Weida YAN, Kazumasa SEKO, Michio HORI, Takashi YAMAMOTO, Naoya HASEGAWA
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Publication number: 20190024712Abstract: A double-row self-aligning roller bearing, which is suitable for receiving an axial load and a radial load, and loads having different magnitudes acting on rollers in two rows, and achieves sufficient load capacity for the rollers that receive axial load within the constraint of dimensional standards, is provided. The double-row self-aligning roller bearing includes inner and outer rings; and rollers in two rows arranged in a bearing width direction interposed between the inner and outer rings and having lengths different from each other. The roller has an outer peripheral surface of a cross-sectional shape along a raceway surface of the outer ring having a spherical shape. Length of the longer rollers is equal to or greater than 39% of the bearing width. A ratio of contact angle of the shorter rollers and contact angle of the longer rollers is within a range of 1:4 to 1:2.Type: ApplicationFiled: September 21, 2018Publication date: January 24, 2019Applicant: NTN CORPORATIONInventors: Takashi YAMAMOTO, Kazumasa SEKO, Yasuyuki INOUE, Michio HORI
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Publication number: 20180202489Abstract: A double-row self-aligning roller bearing includes an inner ring, an outer ring having a spherical raceway surface, and rollers in a left row and rollers in a right row interposed between the inner ring and the outer ring, the rollers in the left row and the rollers in the right row each having an outer peripheral surface having a cross-sectional shape along the raceway surface of the outer ring. The length of each roller in the left row and the length of each roller in the right row are different from each other, and the number of the rollers in the left row and the number of the rollers in the right row are different from each other.Type: ApplicationFiled: March 14, 2018Publication date: July 19, 2018Applicant: NTN CORPORATIONInventors: Michio HORI, Yasuyuki INOUE, Kazumasa SEKO