Patents by Inventor Yuji Shimomura

Yuji Shimomura 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).

  • Publication number: 20230349453
    Abstract: A linear motion actuator has a ball screw device having a screw shaft, a nut, and a plurality of balls, a piston mounted on one end of the screw shaft, and a stroke limiting mechanism setting an operation starting point in time of the screw shaft toward a first direction pointed by the one end. The nut has one end face directed to the first direction and a protruding part protruding from the one end face.
    Type: Application
    Filed: October 20, 2021
    Publication date: November 2, 2023
    Applicant: NSK LTD.
    Inventors: Reona UMEI, Yasumi WATANABE, Yuji SHIMOMURA
  • Patent number: 11680628
    Abstract: In the ball screw device, the circulation path that returns balls from the end point to the start point of the load path includes a return path, scooping paths, and connecting paths. The scooping path has an arc-shaped center line that is curved outward in the radial direction as going toward the reference imaginary flat plane including the center axis of the screw shaft and the center line of the return path in the circumferential direction. The connecting path is arranged on the reference imaginary flat plane and includes a straight path having a linear center line extending in a direction orthogonal to the center axis of the screw shaft. When the radius of curvature of the center line of the scooping path is R1, the scooping angle is ?, and the entire length of the straight path is S, R1 cos(90°??)+S is made larger than the diameter of the balls.
    Type: Grant
    Filed: March 10, 2021
    Date of Patent: June 20, 2023
    Assignee: NSK LTD.
    Inventors: Kazuya Yamada, Yuji Shimomura, Kanta Sato, Yasuaki Abe
  • Patent number: 11662003
    Abstract: A ball screw device has a screw shaft; a nut; a circulation part; and balls; a housing concave groove provided on the outer circumferential surface of the nut and linearly extending in the axial direction and opening to end surfaces on both outer sides in the axial direction of the nut, a circulation part arranged inside the housing concave groove, and the circulation part being prevented from displacing toward the outer side in the radial direction and displacing in the circumferential direction with respect to the nut by engaging an engaging convex portion of a fixing portion provided in the end portion on each of both outer sides in the axial direction of the circulation part with an engaging recess portion provided in the end portion of each of both outer sides in the axial direction of the housing concave groove.
    Type: Grant
    Filed: March 12, 2021
    Date of Patent: May 30, 2023
    Assignee: NSK LTD.
    Inventors: Kazuya Yamada, Yuji Shimomura, Yasuaki Abe, Kanta Sato
  • Publication number: 20230087898
    Abstract: In the ball screw device, the circulation path that returns balls from the end point to the start point of the load path includes a return path, scooping paths, and connecting paths. The scooping path has an arc-shaped center line that is curved outward in the radial direction as going toward the reference imaginary flat plane including the center axis of the screw shaft and the center line of the return path in the circumferential direction. The connecting path is arranged on the reference imaginary flat plane and includes a straight path having a linear center line extending in a direction orthogonal to the center axis of the screw shaft. When the radius of curvature of the center line of the scooping path is R1, the scooping angle is ?, and the entire length of the straight path is S, R1 cos(90°??)+S is made larger than the diameter of the balls.
    Type: Application
    Filed: March 10, 2021
    Publication date: March 23, 2023
    Applicant: NSK LTD.
    Inventors: Kazuya YAMADA, Yuji SHIMOMURA, Kanta SATO, Yasuaki ABE
  • Publication number: 20230015290
    Abstract: A ball screw device has a screw shaft; a nut; a circulation part; and balls; a housing concave groove provided on the outer circumferential surface of the nut and linearly extending in the axial direction and opening to end surfaces on both outer sides in the axial direction of the nut, a circulation part arranged inside the housing concave groove, and the circulation part being prevented from displacing toward the outer side in the radial direction and displacing in the circumferential direction with respect to the nut by engaging an engaging convex portion of a fixing portion provided in the end portion on each of both outer sides in the axial direction of the circulation part with an engaging recess portion provided in the end portion of each of both outer sides in the axial direction of the housing concave groove.
    Type: Application
    Filed: March 12, 2021
    Publication date: January 19, 2023
    Applicant: NSK Ltd.
    Inventors: Kazuya YAMADA, Yuji SHIMOMURA, Yasuaki ABE, Kanta SATO
  • Patent number: 10359102
    Abstract: A friction roller-type reduction gear includes a sun roller concentric with an input shaft, a ring roller having a stationary ring roller element and a moveable ring roller element, intermediate rollers in rolling contact with an outer peripheral surface of the sun roller and an inner peripheral surface of the ring roller, a coupling part coupling the ring roller and the output shaft, and a loading cam mechanism having a cam ring for changing contact surface pressure of each rolling contact surface. The outer surface of the sun roller is a concave curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped concave curve, and an outer surface of the intermediate roller is a convex curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped convex curve.
    Type: Grant
    Filed: February 24, 2016
    Date of Patent: July 23, 2019
    Assignee: NSK LTD.
    Inventors: Hiroshi Kawahara, Hiroyasu Yoshioka, Tetsu Takehara, Yuji Shimomura
  • Patent number: 10214671
    Abstract: The working fluid composition for a refrigerating machine of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant. The refrigerating machine oil of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and by being used together with a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: February 26, 2019
    Assignee: JX NIPPON OIL & ENERGY CORPORATION
    Inventors: Yuji Shimomura, Katsuya Takigawa
  • Publication number: 20180347675
    Abstract: A friction roller-type reduction gear includes a sun roller arranged concentrically with an input shaft, a ring roller having a stationary ring roller element and a moveable ring roller element, a plurality of intermediate rollers configured to be in rolling contact with an outer peripheral surface of the sun roller and an inner peripheral surface of the ring roller, a coupling part configured to couple the ring roller and the output shaft, and a loading cam mechanism having a cam ring and configured to change a contact surface pressure of each rolling contact surface. The outer peripheral surface of the sun roller is a concave curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped concave curve, and an outer peripheral surface of the intermediate roller is a convex curved surface of which a shape of an outer edge in an axial cross-section is a single circular arc-shaped convex curve.
    Type: Application
    Filed: February 24, 2016
    Publication date: December 6, 2018
    Applicant: NSK LTD.
    Inventors: Hiroshi KAWAHARA, Hiroyasu YOSHIOKA, Tetsu TAKEHARA, Yuji SHIMOMURA
  • Publication number: 20160208154
    Abstract: The working fluid composition for a refrigerating machine of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant. The refrigerating machine oil of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and by being used together with a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant.
    Type: Application
    Filed: March 18, 2016
    Publication date: July 21, 2016
    Applicant: Nippon Oil Corporation
    Inventors: Yuji Shimomura, Katsuya Takigawa
  • Patent number: 9321948
    Abstract: The working fluid composition for a refrigerating machine of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant. The refrigerating machine oil of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and by being used together with a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: April 26, 2016
    Assignee: Nippon Oil Corporation
    Inventors: Yuji Shimomura, Katsuya Takigawa
  • Patent number: 9090806
    Abstract: The working fluid composition for a refrigerating machine of this invention comprises a base oil containing an ether-based compound, an amine salt of an acidic phosphoric acid ester, at least one compound selected from the group consisting of amine-based antioxidants, metal inactivating agents and alicyclic epoxy compounds, and an unsaturated fluorinated hydrocarbon refrigerant. The refrigerating machine oil of the invention comprises a base oil containing an ether-based compound, an amine salt of an acidic phosphoric acid ester, and at least one compound selected from the group consisting of amine-based antioxidants, metal inactivating agents and alicyclic epoxy compounds, and it is to be used together with an unsaturated fluorinated hydrocarbon refrigerant.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: July 28, 2015
    Assignee: JX NIPPON OIL & ENERGY CORPORATION
    Inventors: Katsuya Takigawa, Yuji Shimomura, Masanori Saito, Ken Sawada, Takeshi Okido
  • Patent number: 8876654
    Abstract: A toroidal continuously variable transmission of the present invention comprises: input side disks (1a, 1b) and output side disks (6) being supported concentric with each other such that the disks can rotate freely; a trunnion (9) that comprises end sections (36) on both ends on which tilt shafts (13) that are concentric with each other are provided, and a support beam section (15) that extends between both end sections (36), the trunnion (9) being capable of pivotally displacing around the tilt shafts (13); a thrust rolling bearing (17); and a power roller (8) that is supported to the inside surface of the trunnion (9) by way of the thrust rolling bearing (17) such that it rotates freely; wherein the support beam section (15) comprises an inside surface having a cylindrical convex surface (14); the thrust rolling bearing (17) comprises an outer race (18a) having an outside surface with a concave section (19a) that fits with the cylindrical convex surface (14) of the support beam section (15), and a plurality
    Type: Grant
    Filed: November 24, 2010
    Date of Patent: November 4, 2014
    Assignee: NSK Ltd.
    Inventors: Hiroki Nishii, Toshihiko Sato, Eiji Inoue, Toshiro Toyoda, Hiroyasu Yoshioka, Yuji Shimomura, Shin Yamamoto
  • Patent number: 8796193
    Abstract: The first refrigerating machine oil composition of the invention comprises a predetermined base oil, and at least one ester additive selected from esters of a monobasic fatty acid having 12 or more carbon atoms and a monohydric alcohol having 1-24 carbon atoms, and an ester of a chain-like dibasic acid and a monohydric alcohol. The second refrigerating machine oil composition of the invention comprises a predetermined base oil, and at least one oxygen-containing compound selected from the following (A1)-(A6). The third refrigerating machine oil composition of the invention comprises a predetermined base oil, and at least one oxygen-containing compound selected from the following (A1), (A2), (A4), (A7) and (A8).
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: August 5, 2014
    Assignee: Nippon Oil Corporation
    Inventors: Kazuo Tagawa, Yuji Shimomura, Toshiyuki Obata, Katsuya Takigawa
  • Publication number: 20140209830
    Abstract: The refrigerator oil of the invention comprises an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 fatty acid of 50-100% by mole, a content of a C5-C9 branched fatty acid of at least 30% by mole and a content of a C5 or lower straight-chain fatty acid of not greater than 40% by mole, and it is used with a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant. The working fluid composition for a refrigerating machine according to the invention comprises the ester and a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant.
    Type: Application
    Filed: March 31, 2014
    Publication date: July 31, 2014
    Applicant: NIPPON OIL CORPORATION
    Inventors: Yuji SHIMOMURA, Katsuya TAKIGAWA
  • Patent number: 8318040
    Abstract: The refrigerating machine oil of the invention is characterized by comprising an ester of a polyhydric alcohol and fatty acids with a content of a C10-C13 branched fatty acid of 50% by mole or greater. The working fluid composition for a refrigerating machine of the invention is characterized in that the working fluid composition comprises an ester of a polyhydric alcohol and fatty acids with a content of a C10-C13 branched fatty acid of 50% by mole or greater, and a refrigerant.
    Type: Grant
    Filed: March 11, 2008
    Date of Patent: November 27, 2012
    Assignee: Nippon Oil Corporation
    Inventors: Ken Sawada, Yuji Shimomura, Katsuya Takigawa
  • Patent number: 8299006
    Abstract: The present invention provides a refrigerating machine oil, a compressor oil composition, a hydraulic oil composition, a metalworking oil composition, a heat treating oil composition, a lubricating oil composition for machine tools and a lubricating oil composition which comprise a lubricating oil base oil having % CA of not more than 2, % CP/% CN of not less than 6 and an iodine value of not more than 2.5.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: October 30, 2012
    Assignee: Nippon Oil Corporation
    Inventors: Kazuo Tagawa, Yuji Shimomura, Ken Sawada, Katsuya Takigawa, Toshio Yoshida, Shinichi Mitsumoto, Eiji Akiyama, Junichi Shibata, Satoshi Suda, Hideo Yokota, Masahiro Hata, Hiroyuki Hoshino, Hajime Nakao, Shozaburo Konishi
  • Publication number: 20120228541
    Abstract: The working fluid composition for a refrigerating machine of this invention comprises a base oil containing an ether-based compound, an amine salt of an acidic phosphoric acid ester, at least one compound selected from the group consisting of amine-based antioxidants, metal inactivating agents and alicyclic epoxy compounds, and an unsaturated fluorinated hydrocarbon refrigerant. The refrigerating machine oil of the invention comprises a base oil containing an ether-based compound, an amine salt of an acidic phosphoric acid ester, and at least one compound selected from the group consisting of amine-based antioxidants, metal inactivating agents and alicyclic epoxy compounds, and it is to be used together with an unsaturated fluorinated hydrocarbon refrigerant.
    Type: Application
    Filed: August 16, 2010
    Publication date: September 13, 2012
    Applicant: JX NIPPON OIL & ENERGY CORPORATION
    Inventors: Katsuya Takigawa, Yuji Shimomura, Masanori Saito, Ken Sawada, Takeshi Okido
  • Patent number: 8247360
    Abstract: The present invention provides a refrigerating machine oil, a compressor oil composition, a hydraulic oil composition, a metalworking oil composition, a heat treating oil composition, a lubricating oil composition for machine tools and a lubricating oil composition which comprise a lubricating oil base oil having % CA of not more than 2, % CP/% CN of not less than 6 and an iodine value of not more than 2.5.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: August 21, 2012
    Assignee: Nippon Oil Corporation
    Inventors: Kazuo Tagawa, Yuji Shimomura, Ken Sawada, Katsuya Takigawa, Toshio Yoshida, Shinichi Mitsumoto, Eiji Akiyama, Junichi Shibata, Satoshi Suda, Hideo Yokota, Masahiro Hata, Hiroyuki Hoshino, Hajime Nakao, Shozaburo Konishi
  • Patent number: 8236740
    Abstract: The present invention provides a refrigerating machine oil, a compressor oil composition, a hydraulic oil composition, a metalworking oil composition, a heat treating oil composition, a lubricating oil composition for machine tools and a lubricating oil composition which comprise a lubricating oil base oil having % CA of not more than 2, % CP/% CN of not less than 6 and an iodine value of not more than 2.5.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: August 7, 2012
    Assignee: Nippon Oil Corporation
    Inventors: Kazuo Tagawa, Yuji Shimomura, Ken Sawada, Katsuya Takigawa, Toshio Yoshida, Shinichi Mitsumoto, Eiji Akiyama, Junichi Shibata, Satoshi Suda, Hideo Yokota, Masahiro Hata, Hiroyuki Hoshino, Hajime Nakao, Shozaburo Konishi
  • Patent number: 8232233
    Abstract: The present invention provides a refrigerating machine oil, a compressor oil composition, a hydraulic oil composition, a metalworking oil composition, a heat treating oil composition, a lubricating oil composition for machine tools and a lubricating oil composition which comprise a lubricating oil base oil having % CA of not more than 2, % CP/% CN of not less than 6 and an iodine value of not more than 2.5.
    Type: Grant
    Filed: November 1, 2011
    Date of Patent: July 31, 2012
    Assignee: Nippon Oil Corporation
    Inventors: Kazuo Tagawa, Yuji Shimomura, Ken Sawada, Katsuya Takigawa, Toshio Yoshida, Shinichi Mitsumoto, Eiji Akiyama, Junichi Shibata, Satoshi Suda, Hideo Yokota, Masahiro Hata, Hiroyuki Hoshino, Hajime Nakao, Shozaburo Konishi