Patents by Inventor Lung-Wen Tsai

Lung-Wen Tsai 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: 6837816
    Abstract: A motor-integrated transmission mechanism for use in parallel hybrid electric vehicles. The transmission can provide five basic modes of operation that can be further classified into sixteen sub-modes: one electric motor mode, four engine modes, four engine/charge modes, three power modes and four regenerative braking modes. Each of these sub-modes can be grouped into like clutching conditions, providing the functional appearance of a conventional 4-speed automatic transmission, with electric launch, engine-only, engine/charge, power-assist, and regeneration capability. CVT capability is provided with one of the engine/charge modes. The transmission can be incorporated in front-wheel drive and in rear-wheel drive vehicles.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: January 4, 2005
    Inventors: Lung-Wen Tsai, Gregory A. Schultz
  • Patent number: 6664126
    Abstract: This invention provides a fabrication process for manufacturing of truly 3-dimensional micromechanisms which takes advantages of SOI (silicon-on-insulator) wafers each of which is processed to create a respective structural element of the 3-dimensional micromechanisms by DRIE (deep reactive ion etching) of the wafer and thermal oxidation of the trenches opened during the DRIE etching. The wafers are sequentially bonded into a multistack structure from which the 3-D micromechanism. is released by XeF2 etching. Thermally grown SiO2 is used as structural material for the 3-D micromechanism.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: December 16, 2003
    Assignee: University of Maryland, College Park
    Inventors: Donald Lad Devoe, Lung-Wen Tsai
  • Publication number: 20030199352
    Abstract: Disclosed is a motor-integrated transmission mechanism for use in parallel hybrid electric vehicles. The transmission can provide five basic modes of operation that can be further classified into sixteen sub-modes: one electric motor mode, four engine modes, four engine/charge modes, three power modes and four regenerative braking modes. Each of these sub-modes can be grouped into like clutching conditions, providing the functional appearance of a conventional 4-speed automatic transmission, with electric launch, engine-only, engine/charge, power-assist, and regeneration capability. CVT capability is provided with one of the engine/charge modes. The transmission can be incorporated in front-wheel drive and in rear-wheel drive vehicles.
    Type: Application
    Filed: February 10, 2003
    Publication date: October 23, 2003
    Inventors: Lung-Wen Tsai, Gregory A. Schultz
  • Patent number: 6592484
    Abstract: Disclosed is a novel parallel hybrid transmission that transmits torque from two power sources to the drive wheels of a vehicle. The transmission functions with a single heat engine and a single electric motor/generator. Through the use of a compound planetary gear train and four automatically controlled clutches, the transmission is able to (i) sum torque from the two power sources to drive the vehicle; (ii) split torque from the heat engine to drive the vehicle and charge the batteries; (iii) transmit torque individually from either of the two power sources; and (iv) operate as a one- or two-degree-of-freedom mechanism. The configuration of clutches and the compound planetary gear train enable thirteen modes of operation, namely, one motor-only mode, three combined motor and engine modes, one continuous variable transmission/charging mode, four engine-only modes, and four regenerative braking modes.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: July 15, 2003
    Inventors: Lung-Wen Tsai, Gregory A. Schultz
  • Patent number: 5656905
    Abstract: A new generation of hybrid form multi-axis machine tools is described. The hybrid machine tools comprise a position mechanism and an orientation mechanism. Both mechanisms are three-DOF parallel mechanisms that can be connected either in series to form a hybrid parallel-serial manipulator, or in parallel to form a cooperating machine. The position mechanism is used for manipulating the position and the orientation mechanism is used for manipulating the orientation of an object. Six-axes machining of a workpiece is achieved by coordinating the motions of the position and orientation mechanisms. This approach has several important advantages. First of all, a high stiffness, low inertia, and high speed machine tool is realized by using the parallel construction. Secondly, its direct and inverse kinematic solutions could be solved in closed forms which would greatly simplify the control and path planning problems. Thirdly, it has a relatively large workspace in comparison to fully parallel platform manipulators.
    Type: Grant
    Filed: April 3, 1995
    Date of Patent: August 12, 1997
    Inventor: Lung-Wen Tsai
  • Patent number: 5301566
    Abstract: A Six-Degree-of-Freedom Parallel-Manipulator having three inextensible limbs for manipulating a platform is described in which the three inextensible limbs are attached via universal joints to the platform at non-collinear points. Each of the inextensible limbs is also attached via universal joints to a two-degree-of-freedom parallel driver such as a five-bar lineage, a pantograph, or a bidirectional linear stepper motor. The drivers move the lower ends of the limbs parallel to a fixed base and thereby provide manipulation of the platform. The actuators are mounted on the fixed base without using any power transmission devices such as gears or belts.
    Type: Grant
    Filed: August 20, 1993
    Date of Patent: April 12, 1994
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics & Space Administration
    Inventors: Farhad Tahmasebi, Lung-Wen Tsai
  • Patent number: 5279176
    Abstract: A Six-Degree-of-Freedom Parallel-Manipulator having three inextensible limbs for manipulating a platform is described in which the three inextensible limbs are attached via universal joints to the platform at non-collinear points. Each of the inextensible limbs is also attached via universal joints to a two-degree-of-freedom parallel driver such as a five-bar lineage, a pantograph, or a bidirectional linear stepper motor. The drivers move the lower ends of the limbs parallel to a fixed base and thereby provide manipulation of the platform. The actuators are mounted on the fixed base without using any power transmission devices such as gears or belts.
    Type: Grant
    Filed: July 20, 1992
    Date of Patent: January 18, 1994
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Farhad Tahmasebi, Lung-Wen Tsai
  • Patent number: 5245263
    Abstract: A new and innovative concept for the control of backlash in gear-coupled transmission mechanisms. The concept utilizes redundant unidirectional drives to assure positive coupling of gear meshes at all times. Based on this concept, a methodology for the enumeration of admissible redundant-drive backlash-free robotic mechanisms has been established. Some typical two- and three-DOF mechanisms are disclosed. Furthermore, actuator torques have been derived as functions of either joint torques or end-effector dynamic performance requirements. A redundantly driven gear coupled transmission mechanism manipulator has a fail-safe advantage in that, except of the loss of backlash control, it can continue to function when one of its actuators fails. A two-DOF backlash-free arm has been reduced to practice to demonstrate the principle.
    Type: Grant
    Filed: September 13, 1991
    Date of Patent: September 14, 1993
    Assignee: University of Maryland
    Inventors: Lung-Wen Tsai, Sun-Lai Chang
  • Patent number: 4489683
    Abstract: A crankshaft mounted secondary shaking force balancer for multicylinder engines and the like in which eccentrically rotating balance weights carried on the crankshaft and arranged for substantial primary balance are combined in oppositely rotating groups of weights driven by stationary ring or sun gears and associated planetary gears to provide coacting rotating forces that combine to apply directly to the crankshaft a secondary shaking force reciprocating at twice crankshaft speed and available to balance equivalent oppositely directed shaking forces developed by the crankshaft connected moving components of the engine.
    Type: Grant
    Filed: April 30, 1982
    Date of Patent: December 25, 1984
    Assignee: General Motors Corporation
    Inventors: Lung-Wen Tsai, Thomas J. Johnson
  • Patent number: 4480607
    Abstract: An even firing 90.degree. V6 four stroke cycle engine is provided with a single line balancer having a combination of primary balance weights and secondary Oldham coupling balancers rotating opposite crankshaft rotation which, combined with crankshaft counterweights, provide complete offsetting of the engine primary rotating unbalance couple together with offsetting of a large portion of the engine secondary rotating unbalance couple and leaving a small residual secondary unbalance couple for absorption by the engine mounting system.
    Type: Grant
    Filed: August 1, 1983
    Date of Patent: November 6, 1984
    Assignee: General Motors Corporation
    Inventors: Lung-Wen Tsai, Robert L. Jacques
  • Patent number: 4452592
    Abstract: A hybrid straight and curved guide phase change coupling device in which end members rotatable on spaced parallel axes in opposed spaced relation are connected by an intermediate member having guide means constraining lateral motion of the intermediate member to a straight diametrical path with respect to one of the end members and to a curved path with respect to the other of the end members whereby a cyclic phase change or velocity ratio variation is provided during rotation of the two end members at identical overall cyclic speeds.
    Type: Grant
    Filed: June 1, 1982
    Date of Patent: June 5, 1984
    Assignee: General Motors Corporation
    Inventor: Lung-Wen Tsai
  • Patent number: 4440123
    Abstract: A half speed balancer for unbalanced mechanisms such as internal combustion engines comprises an Oldham coupling device with a central coupler that orbits in a curved (usually circular) path at a frequency twice the speed of the coupling rotation. The balancer substitutes for an equivalent rotating eccentric weight when driven at only half the rotational speed thus causing reduced bearing friction and noise and may be used in multiples like eccentric weights to offset various unbalance conditions.
    Type: Grant
    Filed: January 28, 1982
    Date of Patent: April 3, 1984
    Assignee: General Motors Corporation
    Inventor: Lung-Wen Tsai