Patents by Inventor Akio Kato

Akio Kato 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).

  • Patent number: 9562593
    Abstract: An object of the present invention is to provide a chain guide superior in silence, which includes: a guide base extending in a traveling direction of a chain; a plurality of roller shafts attached to the guide base at an interval along the traveling direction of the chain; and rollers each rotatably supported by one of the roller shafts. The roller has a cylindrical outer circumferential surface for guiding the chain. The outer circumferential surface of the roller has a cylindricity not greater than 20 ?m.
    Type: Grant
    Filed: June 8, 2012
    Date of Patent: February 7, 2017
    Assignee: NTN CORPORATION
    Inventors: Shinji Oishi, Akio Kato, Takahiro Yamashita, Katsufumi Abe
  • Publication number: 20160348764
    Abstract: A chain transmission device for driving camshafts is provided, the device including a chain including a loose side chain portion, and trained around the crank sprocket and the cam sprockets, and a chain guide mounted on the outer side of the loose side chain portion so as to be pivotable about one of the two end portions of the chain guide, and provided with a plurality of rotatable rollers. An adjustment force is applied to the other of the two end portions of the chain guide by a chain tensioner such that the chain guide is biased toward the chain, so that the rollers of the chain guide can guide the chain by rolling. The winding angle of the portion of the chain located on the outer periphery of the roller located closest to the crank sprocket is set to be 170 degrees or over so as to reduce noise.
    Type: Application
    Filed: February 3, 2015
    Publication date: December 1, 2016
    Inventors: Akio KATO, Takahiro YAMASHITA, Hisataka HASEGAWA
  • Patent number: 9464699
    Abstract: A chain guide includes a guide base (21) disposed to face one side of a timing chain (5) that transmits torque, the chain guide having an opposed pair of side plates (22) each formed with a plurality of shaft engaging portions (25) arranged along a circular arc. Roller shafts (31) have their ends supported by the respective shaft engaging portions (25). Rollers (41) for guiding the chain are rotatably supported by the respective roller shafts (31). Noncylidrical surface engaging portions are formed on the ends of the roller shafts (31) and on closed ends of the shaft engaging portions (50) to rotationally fix the roller shafts (31), thereby preventing the roller shafts (31) from rotating under drag torque applied from the rollers (41).
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: October 11, 2016
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi, Goro Nakao
  • Patent number: 9429216
    Abstract: A chain guide and a chain tensioner device using the chain guide. A roller, brought into contact with a chain, comprises a support shaft supported by an opposing guide base provided along the running direction of the chain, and roller bearings each having a steel outer ring on the outer peripheral surface of the support shaft so as to be brought into contact with the chain. The roller is also configured to be assembled by inserting opposite ends of the support shaft into support recesses on facing wall surfaces of the guide base. The roller has a vibration damping material between the support shaft and the support recess of each of the plate members.
    Type: Grant
    Filed: February 15, 2012
    Date of Patent: August 30, 2016
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Takahiro Yamashita, Katsufumi Abe
  • Publication number: 20160215861
    Abstract: It is an object of the present invention to provide a chain transmission device including rolling-type chain guides capable of guiding a chain quietly. In the chain transmission deice including the chain guides in which a plurality of spaced apart rollers for guiding the chain are arranged, distance L (m) between the contact points of a trained portion of the chain is set to satisfy the following inequality: L < 1 2 ? ? ? MAX ? T ? ( 1 ) where ?MAX is the maximum excitation frequency (Hz) from a crank shaft, ? is the mass of the chain per unit length (kg/m), and T is the time-average tension of the chain (N).
    Type: Application
    Filed: September 11, 2014
    Publication date: July 28, 2016
    Inventors: Akio KATO, Takahiro YAMASHITA, Hisataka HASEGAWA
  • Patent number: 9400046
    Abstract: A chain guide includes roller element bearings adapted to guide, while rolling, a timing chain through which torque is transmitted. The chain guide further includes a guide base arranged along one side of the timing chain and having an opposed pair of side plates. Each side plate is formed with plural shaft engaging portions arranged so as to lie on a circular arc. The chain guide further includes roller shafts having their ends supported by the respective shaft engaging portions, and rotatably supporting the roller element bearings. An oil guide hole is formed in a wall surface of each shaft engaging portion facing the end surface of the roller shaft so as to extend through the side plate to its outer side surface.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: July 26, 2016
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi, Goro Nakao, Makoto Okasaka, Takashi Tsujimoto
  • Patent number: 9285019
    Abstract: A timing chain is looped over a driving sprocket attached to a crankshaft and driven sprockets attached to camshafts. A pivotable chain guide having a plurality of rotatable rollers for guiding movements of a timing chain is provided on one side of a slack side of the timing chain. Adjustment force of a chain tensioner is applied to a remote end of the pivotable chain guide remote from a center of pivoting movement of the pivotable chain guide, thereby pressing the plurality of rotatable rollers against the timing chain. The ratio (D1/D2) between a pitch circle diameter D1 of the driving sprocket and an outer diameter D2 of the plurality of rotatable rollers is determined within a range of 5/3 to 5/1.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: March 15, 2016
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi
  • Patent number: 9273759
    Abstract: A chain guide having excellent durability is provided. The chain guide includes a guide base arranged along a portion of an outer periphery of a chain for transmitting torque and elongated in the direction in which the chain travels; a plurality of roller shafts attached to the guide base so as to be spaced apart from each other along the direction in which the chain travels; and rollers rotatably supported by the respective roller shafts. The distance between the centers of each adjacent pair of the rollers is set to be shorter in the area where a larger load is applied to the rollers.
    Type: Grant
    Filed: September 6, 2012
    Date of Patent: March 1, 2016
    Assignee: NTN Corporation
    Inventors: Akio Kato, Shinji Oishi
  • Patent number: 9261170
    Abstract: A chain guide is provided by which a chain can be guided silently. The chain guide includes: a guide base arranged along a portion of the outer periphery of a chain for transmitting torque and elongated in the direction in which the chain travels; a plurality of roller shafts spaced apart from each other in the longitudinal direction of the guide base; and a plurality of rollers for guiding the chain. The rollers are rotatably supported by the respective roller shafts. The rollers guide the chain by rolling. An arrangement interval between each adjacent pair of the rollers is set such that any two of the pins by which pieces of the chain are joined together do not pass any two of the rollers at the same time.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: February 16, 2016
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi
  • Patent number: 9206887
    Abstract: The present invention is to suppress wear of outer diameter surfaces of chain guiding rollers (41) in a chain guide and extend the life. Respective shaft ends of a plurality of roller shafts (31) are supported by pairs of facing side plate portions (22) of guide bases (21) arranged to face each other in a one-side part of a timing chain (5) for transmitting torque. Each of the rollers (41) formed by a plurality of chain guiding roller bearings is rotatably supported by each of the plurality of roller shafts (31). Rollers whose surface hardness is greater than surface hardness of the timing chain (5) by 4 points or more of Rockwell hardness are used as the rollers (41), so as to prevent earlier wear of the outer diameter surfaces of the rollers (41) due to contact with the timing chain (5).
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: December 8, 2015
    Assignee: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi
  • Publication number: 20150323047
    Abstract: Disclosed is a lightweight and inexpensive chain guide that has little mechanical loss. The chain guide comprises: a plurality of rollers (2) which make contact with a chain; a chain guide base (10) which supports the plurality of the rollers (2) disposed along a direction of travel of the chain, and a plurality of shafts (3) attached to the chain guide base (10) at predetermined intervals along the direction of travel of the chain. Each of the rollers (2) includes a rolling-element bearing portion constituted of a cylindrical outer ring main body (20) encompassing an outer circumferential face of the shaft (3), and a plurality of rolling elements (21) disposed between the outer circumferential face of the shaft and an inner circumferential face of the outer ring main body (20). The outer ring main body (20) is supported on the chain guide base (10) via the shaft (3) so as to be in rolling contact with the chain.
    Type: Application
    Filed: July 17, 2015
    Publication date: November 12, 2015
    Inventor: Akio KATO
  • Patent number: 9115787
    Abstract: Disclosed is a lightweight and inexpensive chain guide that has little mechanical loss. The chain guide comprises: a plurality of rollers (2) which make contact with a chain; a chain guide base (10) which supports the plurality of the rollers (2) disposed along a direction of travel of the chain, and a plurality of shafts (3) attached to the chain guide base (10) at predetermined intervals along the direction of travel of the chain. Each of the rollers (2) includes a rolling-element bearing portion constituted of a cylindrical outer ring main body (20) encompassing an outer circumferential face of the shaft (3), and a plurality of rolling elements (21) disposed between the outer circumferential face of the shaft and an inner circumferential face of the outer ring main body (20). The outer ring main body (20) is supported on the chain guide base (10) via the shaft (3) so as to be in rolling contact with the chain.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: August 25, 2015
    Assignee: NTN Corporation
    Inventor: Akio Kato
  • Patent number: 9032926
    Abstract: The present invention provides a timing chain drive device which has high mechanical strength of the timing chain contact surface and small sliding resistance, and which, even when being brought into contact with a timing chain running at high speed, is difficult to wear. A first chain guide and a second chain guide, which give tension to a timing chain so as to prevent the timing chain from being slackened, are arranged, and a plurality of rollers, each of which is supported by a rolling element, are arrayed in each of the first chain guide and the second chain guide so as to be brought into contact with the timing chain.
    Type: Grant
    Filed: February 22, 2012
    Date of Patent: May 19, 2015
    Assignee: NTN Corporation
    Inventors: Akio Kato, Takahiro Yamashita, Katsufumi Abe
  • Publication number: 20150105197
    Abstract: A chain guide includes roller element bearings adapted to guide, while rolling, a timing chain through which torque is transmitted. The chain guide further includes a guide base arranged along one side of the timing chain and having an opposed pair of side plates. Each side plate is formed with plural shaft engaging portions arranged so as to lie on a circular arc. The chain guide further includes roller shafts having their ends supported by the respective shaft engaging portions, and rotatably supporting the roller element bearings. An oil guide hole is formed in a wall surface of each shaft engaging portion facing the end surface of the roller shaft so as to extend through the side plate to its outer side surface.
    Type: Application
    Filed: May 24, 2013
    Publication date: April 16, 2015
    Applicant: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi, Goro Nakao, Makoto Okasaka, Takashi Tsujimoto
  • Publication number: 20150018149
    Abstract: A chain guide includes a guide base (21) disposed to face one side of a timing chain (5) for transmitting torque, and having an opposed pair of side plates (22) each formed with a plurality of shaft engaging portions (25) arranged along a circular arc. Roller shafts (31) have their ends supported by the respective shaft engaging portions (25) Rollers (41) for guiding the chain are rotatably supported by the respective roller shafts (31). Noncylidrical surface engaging portions are formed on the ends of the roller shafts (31) and on closed ends of the shaft engaging portions (50) to rotationally fix the roller shafts (31), thereby preventing the roller shafts (31) from rotating under drag torque applied from the rollers (41).
    Type: Application
    Filed: February 25, 2013
    Publication date: January 15, 2015
    Applicant: NTN CORPORATION
    Inventors: Akio Kato, Shinji Oishi, Goro Nakao
  • Publication number: 20140378254
    Abstract: A chain guide is provided which reduces moving resistance of a camshaft-driving, torque-transmitting timing chain. The chain guide includes a guide base (21) provided on one side of the timing chain (5) to face the timing chain and having an opposed pair of side plates (22). The side plates support the respective ends of roller shafts (31) each rotatably supporting a chain-guiding needle roller bearing (41). Each needle roller bearing includes a retainer (43) guided by the needle roller elements (45). With this arrangement, the outer races (42) of the bearings, which guide the movement of the timing chain (5) while kept in rolling contact with the timing chain, encounter less rotational resistance. This in turn reduces moving resistance of the timing chain (5) and thus fuel consumption.
    Type: Application
    Filed: December 27, 2012
    Publication date: December 25, 2014
    Inventors: Akio Kato, Shinji Oishi
  • Publication number: 20140287861
    Abstract: A chain guide having excellent durability is provided. The chain guide includes a guide base arranged along a portion of an outer periphery of a chain for transmitting torque and elongated in the direction in which the chain travels; a plurality of roller shafts attached to the guide base so as to be spaced apart from each other along the direction in which the chain travels; and rollers rotatably supported by the respective roller shafts. The distance between the centers of each adjacent pair of the rollers is set to be shorter in the area where a larger load is applied to the rollers.
    Type: Application
    Filed: September 6, 2012
    Publication date: September 25, 2014
    Inventors: Akio Kato, Shinji Oishi
  • Publication number: 20140274512
    Abstract: An object of the present invention is to provide a chain guide superior in silence, which includes: a guide base extending in a traveling direction of a chain; a plurality of roller shafts attached to the guide base at an interval along the traveling direction of the chain; and rollers each rotatably supported by one of the roller shafts. The roller has a cylindrical outer circumferential surface for guiding the chain. The outer circumferential surface of the roller has a cylindricity not greater than 20 ?m.
    Type: Application
    Filed: June 8, 2012
    Publication date: September 18, 2014
    Inventors: Shinji Oishi, Akio Kato, Takahiro Yamashita, Katsufumi Abe
  • Publication number: 20140179472
    Abstract: A chain guide is provided by which a chain can be guided silently. The chain guide includes: a guide base arranged along a portion of the outer periphery of a chain for transmitting torque and elongated in the direction in which the chain travels; a plurality of roller shafts spaced apart from each other in the longitudinal direction of the guide base; and a plurality of rollers for guiding the chain. The rollers are rotatably supported by the respective roller shafts. The rollers guide the chain by rolling. An arrangement interval between each adjacent pair of the rollers is set such that any two of the pins by which pieces of the chain are joined together do not pass any two of the rollers at the same time.
    Type: Application
    Filed: July 30, 2012
    Publication date: June 26, 2014
    Inventors: Akio Kato, Shinji Oishi
  • Publication number: 20140162820
    Abstract: The present invention is to suppress wear of outer diameter surfaces of chain guiding rollers (41) in a chain guide and extend the life. Respective shaft ends of a plurality of roller shafts (31) are supported by pairs of facing side plate portions (22) of guide bases (21) arranged to face each other in a one-side part of a timing chain (5) for transmitting torque. Each of the rollers (41) formed by a plurality of chain guiding roller bearings is rotatably supported by each of the plurality of roller shafts (31). Rollers whose surface hardness is greater than surface hardness of the timing chain (5) by 4 points or more of Rockwell hardness are used as the rollers (41), so as to prevent earlier wear of the outer diameter surfaces of the rollers (41) due to contact with the timing chain (5).
    Type: Application
    Filed: July 12, 2012
    Publication date: June 12, 2014
    Inventors: Akio Kato, Shinji Oishi