Patents by Inventor Toshimasa Kotani

Toshimasa Kotani 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: 11655770
    Abstract: An engine is provided, which includes an engine body including a cylinder provided with intake and exhaust ports and intake and exhaust valves, intake and exhaust passages, a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage, and a variable phase mechanism configured to change open/close timings of the intake valve while maintaining an open period of the intake valve at a 270° C.A or larger. A geometric compression ratio of the cylinder is 11:1 or higher. In a high-load range, the variable phase mechanism sets the intake valve close timing to be after an intake BDC and to make a ratio of a retarded amount of the intake closing to the geometric compression ratio be 4.58 or above and 6.67 or below, and sets the intake valve open timing to be before a close timing of the exhaust valve.
    Type: Grant
    Filed: January 31, 2022
    Date of Patent: May 23, 2023
    Assignee: Mazda Motor Corporation
    Inventors: Naohiro Yamaguchi, Mitsunori Wasada, Satoshi Imamura, Toshimasa Kotani
  • Patent number: 11635041
    Abstract: An engine is provided, which includes an engine body including a plurality of cylinders, each of the cylinders being provided with an intake port, an exhaust port, an intake valve, and an exhaust valve, an intake passage and an exhaust passage connected to the engine body, and a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage. A geometric compression ratio of the cylinder is 11:1 or higher. An open period of the intake valve is a range of 270° or larger by a crank angle. The exhaust passage includes a plurality of independent exhaust passages, each communicating with the exhaust port of one cylinder or with the exhaust ports of two or more cylinders of which timings of exhaust strokes are discontinuous from each other, and connecting the engine body to the turbine.
    Type: Grant
    Filed: January 31, 2022
    Date of Patent: April 25, 2023
    Assignee: Mazda Motor Corporation
    Inventors: Naohiro Yamaguchi, Mitsunori Wasada, Satoshi Imamura, Toshimasa Kotani
  • Publication number: 20220282674
    Abstract: An engine is provided, which includes an engine body including a cylinder provided with intake and exhaust ports and intake and exhaust valves, intake and exhaust passages, a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage, and a variable phase mechanism configured to change open/close timings of the intake valve while maintaining an open period of the intake valve at a 270° C.A or larger. A geometric compression ratio of the cylinder is 11:1 or higher. In a high-load range, the variable phase mechanism sets the intake valve close timing to be after an intake BDC and to make a ratio of a retarded amount of the intake closing to the geometric compression ratio be 4.58 or above and 6.67 or below, and sets the intake valve open timing to be before a close timing of the exhaust valve.
    Type: Application
    Filed: January 31, 2022
    Publication date: September 8, 2022
    Inventors: Naohiro Yamaguchi, Mitsunori Wasada, Satoshi Imamura, Toshimasa Kotani
  • Publication number: 20220282686
    Abstract: An engine is provided, which includes an engine body including a plurality of cylinders, each of the cylinders being provided with an intake port, an exhaust port, an intake valve, and an exhaust valve, an intake passage and an exhaust passage connected to the engine body, and a turbocharger including a turbine provided to the exhaust passage and a compressor provided to the intake passage. A geometric compression ratio of the cylinder is 11:1 or higher. An open period of the intake valve is a range of 270° or larger by a crank angle. The exhaust passage includes a plurality of independent exhaust passages, each communicating with the exhaust port of one cylinder or with the exhaust ports of two or more cylinders of which timings of exhaust strokes are discontinuous from each other, and connecting the engine body to the turbine.
    Type: Application
    Filed: January 31, 2022
    Publication date: September 8, 2022
    Inventors: Naohiro Yamaguchi, Mitsunori Wasada, Satoshi Imamura, Toshimasa Kotani
  • Patent number: 10047645
    Abstract: A valve train device for an engine includes: a shaft portion; a cam element portion which is mounted on the shaft portion; and an operation member. The cam element portion includes a first end surface cam and a second end surface cam. Each of the first end surface cam and the second end surface cam includes a lift portion. The operation member includes a first operation member and a second operation member. The first operation member causes the cam element portion to move in a first direction, and the second operation member causes the cam element portion to move in a second direction. The first end surface cam includes a first slope portion, and guides the first operation member radially outwardly; and a displacement allowing portion which is formed adjacent to the first slope portion, and allows relative displacement between the first operation member, and the cam element portion.
    Type: Grant
    Filed: May 27, 2015
    Date of Patent: August 14, 2018
    Assignee: MAZDA MOTOR CORPORATION
    Inventors: Akitomo Takagi, Toshimasa Kotani
  • Publication number: 20170191387
    Abstract: A valve train device for an engine includes: a shaft portion; a cam element portion which is mounted on the shaft portion; and an operation member. The cam element portion includes a first end surface cam and a second end surface cam. Each of the first end surface cam and the second end surface cam includes a lift portion. The operation member includes a first operation member and a second operation member. The first operation member causes the cam element portion to move in a first direction, and the second operation member causes the cam element portion to move in a second direction. The first end surface cam includes a first slope portion, and guides the first operation member radially outwardly; and a displacement allowing portion which is formed adjacent to the first slope portion, and allows relative displacement between the first operation member, and the cam element portion.
    Type: Application
    Filed: May 27, 2015
    Publication date: July 6, 2017
    Applicant: MAZDA MOTOR CORPORATION
    Inventors: Akitomo TAKAGI, Toshimasa KOTANI
  • Patent number: 9574465
    Abstract: A cam element portions is configured such that respective maximum lift portions (lift ending points) of both-side end-face cams thereof are provided at respective phases which are different from each other in a rotational direction and that a maximum value of a length, in an axial direction, between respective cam faces of the both-side end-face cams which are provided at the same phase is set to be a distance, in the axial direction, between a first operational member and a second operational member or smaller. Accordingly, in a valve gear of an engine in which cams operative to control opening/closing of a valve are switchable, it can be properly prevented that a camshaft locks and stop rotating because of an operational malfunction of an operational member or the like.
    Type: Grant
    Filed: August 14, 2014
    Date of Patent: February 21, 2017
    Assignee: Mazda Motor Corporation
    Inventors: Akitomo Takagi, Toshimasa Kotani, Shunsuke Habara, Takashi Kashiwabara
  • Patent number: 9546578
    Abstract: A valve operating system for an engine is provided. The system includes first and second detent mechanisms for holding a cam element at a first position when the cam element is shifted to one side in camshaft directions, and at a second position when the cam element is shifted to the other side. The detent mechanisms include first and second detent cams and first and second pushing members, respectively. The first detent cam includes first and second grooves and a first top portion. The second detent cam includes third and fourth grooves and a second top portion. The first and second grooves have inclining portions extending from the first top portion toward bottoms thereof, inclining with respect to the camshaft directions, respectively. The third and fourth grooves have inclining portions extending from the second top portion toward bottoms thereof, inclining with respect to the camshaft directions, respectively.
    Type: Grant
    Filed: January 15, 2015
    Date of Patent: January 17, 2017
    Assignee: Mazda Motor Corporation
    Inventors: Akitomo Takagi, Toshimasa Kotani
  • Patent number: 9347342
    Abstract: A cam element portion comprises a slant portion (reverse-rotation return slope portion), which is positioned on a rotary-delay side from a maximum-lift portion (lift ending point) of an end-face cam and slants inward toward the rotary-delay side from an outer peripheral face of the end-face cam. Accordingly, in a valve gear of an engine in which cams operative to control opening/closing of a valve are switchable, it can be properly prevented that the cam element portion is switched unexpectedly and improperly or an operational member breaks down which are possibly caused by an engine's reverse rotation.
    Type: Grant
    Filed: August 14, 2014
    Date of Patent: May 24, 2016
    Assignee: MAZDA MOTOR CORPORATION
    Inventors: Toshimasa Kotani, Akitomo Takagi, Shunsuke Habara, Takashi Kashiwabara
  • Publication number: 20150204219
    Abstract: A valve operating system for an engine is provided. The system includes first and second detent mechanisms for holding a cam element at a first position when the cam element is shifted to one side in camshaft directions, and at a second position when the cam element is shifted to the other side. The detent mechanisms include first and second detent cams and first and second pushing members, respectively. The first detent cam includes first and second grooves and a first top portion. The second detent cam includes third and fourth grooves and a second top portion. The first and second grooves have inclining portions extending from the first top portion toward bottoms thereof, inclining with respect to the camshaft directions, respectively. The third and fourth grooves have inclining portions extending from the second top portion toward bottoms thereof, inclining with respect to the camshaft directions, respectively.
    Type: Application
    Filed: January 15, 2015
    Publication date: July 23, 2015
    Inventors: Akitomo Takagi, Toshimasa Kotani
  • Publication number: 20150075468
    Abstract: A cam element portions is configured such that respective maximum lift portions (lift ending points) of both-side end-face cams thereof are provided at respective phases which are different from each other in a rotational direction and that a maximum value of a length, in an axial direction, between respective cam faces of the both-side end-face cams which are provided at the same phase is set to be a distance, in the axial direction, between a first operational member and a second operational member or smaller. Accordingly, in a valve gear of an engine in which cams operative to control opening/closing of a valve are switchable, it can be properly prevented that a camshaft locks and stop rotating because of an operational malfunction of an operational member or the like.
    Type: Application
    Filed: August 14, 2014
    Publication date: March 19, 2015
    Applicant: MAZDA MOTOR CORPORATION
    Inventors: Akitomo TAKAGI, Toshimasa KOTANI, Shunsuke HABARA, Takashi KASHIWABARA
  • Publication number: 20150075467
    Abstract: A cam element portion comprises a slant portion (reverse-rotation return slope portion), which is positioned on a rotary-delay side from a maximum-lift portion (lift ending point) of an end-face cam and slants inward toward the rotary-delay side from an outer peripheral face of the end-face cam. Accordingly, in a valve gear of an engine in which cams operative to control opening/closing of a valve are switchable, it can be properly prevented that the cam element portion is switched unexpectedly and improperly or an operational member breaks down which are possibly caused by an engine's reverse rotation.
    Type: Application
    Filed: August 14, 2014
    Publication date: March 19, 2015
    Applicant: MAZDA MOTOR CORPORATION
    Inventors: Toshimasa KOTANI, Akitomo TAKAGI, Shunsuke HABARA, Takashi KASHIWABARA
  • Patent number: 8511263
    Abstract: A pump attaching portion is formed at a specified outside portion of an engine body beside a boss portion of a cylinder-head fastening bolt in such a manner that the pump attaching portion is continuous from the boss portion. The pump attaching portion has an attachment face, which contains a cooling-water introducing port, which is located on the outside of the flange wall and faces toward an engine front side in such a manner that the position of the attachment face is retreated from the flange wall. Accordingly, the sufficient pump-support rigidity can be ensured, restraining the pump attaching portion from projecting greatly toward the side of the engine body.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: August 20, 2013
    Assignee: Mazda Motor Corporation
    Inventors: Yuichi Ayukawa, Ryotaro Nishida, Toshimasa Kotani
  • Publication number: 20100313829
    Abstract: A pump attaching portion is formed at a specified outside portion of an engine body beside a boss portion of a cylinder-head fastening bolt in such a manner that the pump attaching portion is continuous from the boss portion. The pump attaching portion has an attachment face, which contains a cooling-water introducing port, which is located on the outside of the flange wall and faces toward an engine front side in such a manner that the position of the attachment face is retreated from the flange wall. Accordingly, the sufficient pump-support rigidity can be ensured, restraining the pump attaching portion from projecting greatly toward the side of the engine body.
    Type: Application
    Filed: April 30, 2010
    Publication date: December 16, 2010
    Applicant: MAZDA MOTOR CORPORATION
    Inventors: Yuichi AYUKAWA, Ryotaro NISHIDA, Toshimasa KOTANI
  • Patent number: 7739991
    Abstract: A rocker cam is comprised of a first split body and a second split body, which are joined with a joint split face that contains an axial line of a cam shaft. The first split body has a first pin support portion that supports one end portion of the connection pin, and the second split body has a second pin support portion that is located so as to face the first pin support portion and supports the other end portion of the connection pin. The connection pin is supported at the first and second pin support portions at its both end portions. Accordingly, a separation force that acts on the first and second split bodies of the rocker cam during its repeated rocking movement can be reduced without improperly increasing its rigidity.
    Type: Grant
    Filed: January 14, 2008
    Date of Patent: June 22, 2010
    Assignee: Mazda Motor Corporation
    Inventors: Toshimasa Kotani, Hirokazu Matsuura, Shinichi Sugihara
  • Publication number: 20080184946
    Abstract: A rocker cam is comprised of a first split body and a second split body, which are joined with a joint split face that contains an axial line of a cam shaft. The first split body has a first pin support portion that supports one end portion of the connection pin, and the second split body has a second pin support portion that is located so as to face the first pin support portion and supports the other end portion of the connection pin. The connection pin is supported at the first and second pin support portions at its both end portions. Accordingly, a separation force that acts on the first and second split bodies of the rocker cam during its repeated rocking movement can be reduced without improperly increasing its rigidity.
    Type: Application
    Filed: January 14, 2008
    Publication date: August 7, 2008
    Applicant: MAZDA MOTOR CORPORATION
    Inventors: Toshimasa KOTANI, Hirokazu MATSUURA, Shinichi SUGIHARA