Patents by Inventor Keqin Chen

Keqin Chen 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: 11255347
    Abstract: Vibration damping devices and methods utilizing the same for damping vibrations in a fan. A vibration damping device for a fan, the fan having an inlet side of a frame and an exhaust side of the frame and the frame retains a fan mechanism. The vibration damping device includes a mass mT which may include either: a block with a total mass mT; or a finger guard and at least one resilient attachment member having a first spring characteristic, wherein resilient attachment member is configured to be connected to and retain the mass mT. The vibration damping device may be tunable to damp the vibration of fan by (a) varying the total mass mT of the block, or replacing the finger guard, and/or (b) replacing the at least one resilient attachment member with a second resilient attachment member having a second spring characteristic.
    Type: Grant
    Filed: September 19, 2016
    Date of Patent: February 22, 2022
    Assignee: Fortinet, Inc.
    Inventors: Zhi Hon Yang, Shenghua Jiang, Keqin Chen
  • Patent number: 10888018
    Abstract: A cooling system for electrical and electronic devices for hot swapping of a fan module without affecting cooling efficiency due to air backflow, preventing stalling of newly installed exhaust device due to reverse rotation. A check valve assembly having an inlet side frame member, an outlet side frame member, and one or more non-symmetrical valve flaps, each flap having a movable part and a fixed part. The outlet side frame allows the flaps to open under suction pressure on side of the outlet side frame, the inlet side frame disallows the flaps to open under suction pressure on side of the inlet side frame, allowing air to flow in one direction from inlet side frame side to outlet side frame side only. The check valve assembly can be independent of the exhaust device. The check valve assembly can prevent backflow of air during hot swapping of the exhaust device.
    Type: Grant
    Filed: September 19, 2016
    Date of Patent: January 5, 2021
    Assignee: Fortinet, Inc.
    Inventors: Qian Yu, Chenghua Hong, Keqin Chen
  • Publication number: 20180080571
    Abstract: A cooling system for electrical and electronic devices for hot swapping of a fan module without affecting cooling efficiency due to air backflow, preventing stalling of newly installed exhaust device due to reverse rotation. A check valve assembly having an inlet side frame member, an outlet side frame member, and one or more non-symmetrical valve flaps, each flap having a movable part and a fixed part. The outlet side frame allows the flaps to open under suction pressure on side of the outlet side frame, the inlet side frame disallows the flaps to open under suction pressure on side of the inlet side frame, allowing air to flow in one direction from inlet side frame side to outlet side frame side only. The check valve assembly can be independent of the exhaust device. The check valve assembly can prevent backflow of air during hot swapping of the exhaust device.
    Type: Application
    Filed: September 19, 2016
    Publication date: March 22, 2018
    Applicant: Fortinet, Inc.
    Inventors: Qian Yu, Chenghua Hong, Keqin Chen
  • Publication number: 20180080479
    Abstract: Vibration damping devices and methods utilizing the same for damping vibrations in a fan. A vibration damping device for a fan, the fan having an inlet side of a frame and an exhaust side of the frame and the frame retains a fan mechanism. The vibration damping device includes a mass mT which may include either: a block with a total mass mT; or a finger guard and at least one resilient attachment member having a first spring characteristic, wherein resilient attachment member is configured to be connected to and retain the mass mT. The vibration damping device may be tunable to damp the vibration of fan by (a) varying the total mass mT of the block, or replacing the finger guard, and/or (b) replacing the at least one resilient attachment member with a second resilient attachment member having a second spring characteristic.
    Type: Application
    Filed: September 19, 2016
    Publication date: March 22, 2018
    Applicant: Fortinet, Inc.
    Inventors: Zhi Hon Yang, Shenghua Jiang, Keqin Chen
  • Patent number: 9675252
    Abstract: Scanning mechanisms that have application in confocal imaging use electromagnetic actuation to move elements in an optical system. An objective lens mounted to a flexure comprising a magnetic material is actuated in the axial direction by an electromagnet coil. An optical path may pass through the coil. Scanning in transverse directions may be provided using magnetically actuated flexible beams which move the tip of an optical fiber or other pinhole in one or more transverse directions. Actuators may be actuated using driving currents that include an AC component and a DC bias component. The scanning mechanisms may be miniaturized and may be constructed to provide real-time imaging.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: June 13, 2017
    Assignees: British Columbia Cancer Agency Branch, The University of British Colombia
    Inventors: Hadi Mansoor, Haishan Zeng, Mu Chiao, Keqin Chen
  • Publication number: 20140236022
    Abstract: Scanning mechanisms that have application in confocal imaging use electromagnetic actuation to move elements in an optical system. An objective lens mounted to a flexure comprising a magnetic material is actuated in the axial direction by an electromagnet coil. An optical path may pass through the coil. Scanning in transverse directions may be provided using magnetically actuated flexible beams which move the tip of an optical fiber or other pinhole in one or more transverse directions. Actuators may be actuated using driving currents that include an AC component and a DC bias component. The scanning mechanisms may be miniaturized and may be constructed to provide real-time imaging.
    Type: Application
    Filed: September 27, 2012
    Publication date: August 21, 2014
    Applicants: BRITISH COLUMBIA CANCER AGENCY BRANCH, THE UNIVERSITY OF BRITISH COLUMBIA
    Inventors: Haishan Zeng, Hadi Mansoor, Mu Chiao, Keqin Chen
  • Patent number: 6410265
    Abstract: This invention relates to the isolation of a novel putative efflux gene from Pseudomonas mendocina. The putative efflux gene is useful for probing an organism's efflux system to gain an understanding of the mechanisms of solvent tolerance. The invention further provides a Pseudomonas mendocina strain deficient in this gene. This strain is unable to grow in the presence of chloramphenicol and, compared to the wildtype strain, grows slowly in the presence of high concentrations of PHBA.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: June 25, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Kevin Keqin Chen
  • Patent number: 6235882
    Abstract: This invention relates to the isolation of a novel putative efflux gene from Pseudomonas mendocina. The putative efflux gene is useful for probing an organism's efflux system to gain an understanding of the mechanisms of solvent tolerance. The invention further provides a Pseudomonas mendocina strain deficient in this gene. This strain is unable to grow in the presence of chloramphenicol and, compared to the wildtype strain, grows slowly in the presence of high concentrations of PHBA.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: May 22, 2001
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Kevin Keqin Chen
  • Patent number: 6225089
    Abstract: This invention relates to the isolation of a novel putative efflux gene from Pseudomonas mendocina. The putative efflux gene is useful for probing an organism's efflux system to gain an understanding of the mechanisms of solvent tolerance. The invention further provides a Pseudomonas mendocina strain deficient in this gene. This strain is unable to grow in the presence of chloramphenicol and, compared to the wildtype strain, grows slowly in the presence of high concentrations of PHBA.
    Type: Grant
    Filed: June 15, 1999
    Date of Patent: May 1, 2001
    Assignee: E. I. du Pont de Nemours and Company
    Inventor: Kevin Keqin Chen
  • Patent number: 5316935
    Abstract: In accordance with the present invention, there are provided novel, modified subtilisin enzyme(s) having improved catalytic activity and/or stability in organic media.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: May 31, 1994
    Assignee: California Institute of Technology
    Inventors: Frances H. Arnold, Keqin Chen