Patents by Inventor Perry Y. Li

Perry Y. Li 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: 20240077135
    Abstract: Devices and methods for improving the efficiency of an axial piston hydraulic motor or other axial piston hydraulic device. In some embodiments, a valve cam, with specified geometry, is assembled to a conventional axial piston hydraulic device (e.g., hydraulic motor, hydraulic pump, hydraulic pump-motor) in a manner permitting selective rotation of the valve cam relative to the distributor valves (e.g., spool valves). The rotating valve cam facilitates variable piston stroke and can be provided in conjunction with (e.g., joint control) an adjustable swashplate according to a mathematical relationship in order to adjust the displacement of the axial piston hydraulic motor (or other device) while maintaining optimal pre-compression and decompression across a range of operating conditions. This configuration allows, for each desired effective displacement of the hydraulic motor, a set of optimal valve timing to achieve perfect pre-compression and decompression so as to eliminate associated throttling losses.
    Type: Application
    Filed: September 7, 2023
    Publication date: March 7, 2024
    Applicant: Regents of the University of Minnesota
    Inventors: Perry Y. Li, Evan D. Sand
  • Patent number: 8413436
    Abstract: An accumulator system is configured to store energy and includes an accumulator having a liquid chamber coupled to a liquid port and an air chamber coupled to an air port. The liquid chamber and the air chamber are separated by a moveable isolation barrier. An air motor/compressor coupled to the air port is configured to receive a mechanical input and responsively pump air into the accumulator, and to receive pressurized air from the air port and responsively provide a mechanical output. A liquid reservoir is coupled to the liquid port to receive liquid from the liquid chamber as air is pumped into the air chamber and to provide liquid to the liquid chamber as air is removed from the air chamber.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: April 9, 2013
    Assignee: Regents of the University of Minnesota
    Inventors: Perry Y. Li, James D. Van de Ven
  • Patent number: 8286939
    Abstract: A pulse width modulated fluidic valve 3005 includes a cylinder (352) having an elongate bore, a length, and first (344) and second (346) ports which extend from outside the cylinder (352) into the bore. A rotatable spool (302) is carried in the bore and movable in a direction of the length of cylinder (352). The spool (302) has a variable blocking feature (306) which blocks passage of fluid' between the first (344) and second (346) ports as a function of angular position relative to the first (344) and second (346) ports and as a function of linear position along the length of the cylinder (352).
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: October 16, 2012
    Assignee: Regents of the University of Minnesota
    Inventors: Perry Y. Li, Thomas R. Chase
  • Publication number: 20100212743
    Abstract: A pulse width modulated fluidic valve 3005 includes a cylinder (352) having an elongate bore, a length, and first (344) and second (346) ports which extend from outside the cylinder (352) into the bore. A rotatable spool (302) is carried in the bore and movable in a direction of the length of cylinder (352). The spool (302) has a variable blocking feature (306) which blocks passage of fluid between the first (344) and second (346) ports as a function of angular position relative to the first (344) and second (346) ports and as a function of linear position along the length of the cylinder (352).
    Type: Application
    Filed: October 10, 2007
    Publication date: August 26, 2010
    Inventors: Perry Y. Li, Thomas R. Chase
  • Publication number: 20100018196
    Abstract: An accumulator system is configured to store energy and includes an accumulator having a liquid chamber coupled to a liquid port and an air chamber coupled to an air port. The liquid chamber and the air chamber are separated by a moveable isolation barrier. An air motor/compressor coupled to the air port is configured to receive a mechanical input and responsively pump air into the accumulator, and to receive pressurized air from the air port and responsively provide a mechanical output. A liquid reservoir is coupled to the liquid port to receive liquid from the liquid chamber as air is pumped into the air chamber and to provide liquid to the liquid chamber as air is removed from the air chamber.
    Type: Application
    Filed: October 10, 2007
    Publication date: January 28, 2010
    Inventors: Perry Y. Li, James D. Van de Ven
  • Publication number: 20080083894
    Abstract: A pulse width modulated fluidic valve includes a cylinder having an elongate bore, a length and first and second ports which extend from outside the cylinder into the bore. A rotatable spool is carried in the bore and movable in a direction of the length of cylinder. The spool has a variable blocking feature which blocks passage of fluid between the first and second ports as a function of angular position relative to the first and second ports and as a function of linear position along the length of the cylinder.
    Type: Application
    Filed: October 10, 2006
    Publication date: April 10, 2008
    Inventors: Perry Y. Li, Thomas R. Chase
  • Patent number: 7209228
    Abstract: A scanning apparatus includes a support frame and a laser scanner mounted to the frame. A five bar closed loop spherical linkage supports a clamping device for retaining an object. The linkage moves the object through a scanning beam about a spherical surface to facilitate scanning of curved objects. The linkage is mounted on an arm rotatably mounted to the frame and the clamping device is rotatably mounted to the linkage to provide four degrees of freedom. Encoders and motors drive the linkage to provide accurate positioning and providing for digitizing the scanned object.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: April 24, 2007
    Inventors: Perry Y. Li, Chuanqi Chen, Arthur G. Erdman, Zhang Hong, John Byron Raymond
  • Publication number: 20040246494
    Abstract: A scanning apparatus includes a support frame and a laser scanner mounted to the frame. A five bar closed loop spherical linkage supports a clamping device for retaining an object. The linkage moves the object through a scanning beam about a spherical surface to facilitate scanning of curved objects. The linkage is mounted on an arm rotatably mounted to the frame and the clamping device is rotatably mounted to the linkage to provide four degrees of freedom. Encoders and motors drive the linkage to provide accurate positioning and providing for digitizing the scanned object.
    Type: Application
    Filed: November 12, 2003
    Publication date: December 9, 2004
    Inventors: Perry Y. Li, Chuanqi Chen, Arthur G. Erdman, Zhang Hong, John Byron Raymond
  • Publication number: 20030020906
    Abstract: A scanning apparatus includes a support frame and a laser scanner mounted to the frame. A five bar closed loop spherical linkage supports a clamping device for retaining an object. The linkage moves the object through a scanning beam about a spherical surface to facilitate scanning of curved objects. The linkage is mounted on an arm rotatably mounted to the frame and the clamping device is rotatably mounted to the linkage to provide four degrees of freedom. Encoders and motors drive the linkage to provide accurate positioning and providing for digitizing the scanned object.
    Type: Application
    Filed: October 25, 1999
    Publication date: January 30, 2003
    Inventors: PERRY Y. LI, CHUANQI CHEN, ARTHUR G. ERDMAN, ZHANG HONG, JOHN BYRON RAYMOND
  • Patent number: 6322069
    Abstract: A method of synchronizing the arrival of copy sheets at a photoreceptor in an image processing having a copy sheet path having a plurality of segments coupled at given transfer zones, a plurality of copy sheet drives, an image transfer station, a photoreceptor and a controller. The controller directs the image processing apparatus by tracking the movement of copy sheets at the image transfer station in relation to the movement of the photoreceptor, monitoring the movement of copy sheets at the transfer zones, determining the need to adjust the spacing of copy sheets along the plurality of segments of the copy sheet path, and suitably activating selected copy sheet drives.
    Type: Grant
    Filed: March 12, 1999
    Date of Patent: November 27, 2001
    Assignee: Xerox Corporation
    Inventors: Martin Krucinski, Carlo Cloet, Masayoshi Tomizuka, Roberto Horowitz, Sudhendu Rai, David R. Kamprath, Perry Y. Li
  • Patent number: 6021285
    Abstract: An image quality control apparatus controls quality of xerographic images formed by a xerographic imaging system onto a recording medium when at least one sensor which is operative to provide signals to the xerographic imaging system for quality control malfunctions. The image quality control apparatus includes a controller device in communication with the xerographic imaging system. The controller includes a data collection device, a determining device and an input generating device. The data collection device collects and processes sensor data received from the at least one sensor while the at least one sensor is operative. The determining device determines whether the at least one sensor malfunctions.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: February 1, 2000
    Assignee: Xerox Corporation
    Inventors: Lingappa K. Mestha, Sohail A. Dianat, Yao Rong Wang, Perry Y. Li, Michael J. Rice