Patents by Inventor Alvon C. Elrod

Alvon C. Elrod 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: 5551481
    Abstract: A method of manufacturing a direct drive servovalve including the steps of providing a completely packaged drive motor and a hydraulic stage positioning the drive motor upon the hydraulic stage and in engagement with a valve contained within the hydraulic stage applying a signal to the motor which is proportional to a desired output signal from the hydraulic stage moving the motor while measuring the output from the hydraulic stage and when the predetermined desired output is obtained from the hydraulic stage, then securing the motor to the hydraulic stage.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: September 3, 1996
    Assignee: HR Textron Inc.
    Inventor: Alvon C. Elrod, Jr.
  • Patent number: 5508575
    Abstract: A direct drive servovalve wherein a limited angle force motor is interconnected with a spool valve to convert rotary motion of the drive motor rotor to linear motion of the spool for the control of fluid from a source thereof to a load. The permanent magnets utilized in the rotor of the drive motor are positioned in such a manner that a resultant magnetic force is generated so as to urge the rotor against a bearing which supports the rotor shaft so as to substantially eliminate any radially play or sloppiness in the motor rotor.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: April 16, 1996
    Assignee: HR Textron Inc.
    Inventor: Alvon C. Elrod, Jr.
  • Patent number: 5504409
    Abstract: A direct drive servovalve which includes a limited angle force motor having an eccentric engaging a two landed spool for converting rotary motion of the motor rotor into linear motion of the spool so as to control the flow of fluid from a source under pressure thereof of to a load. The two landed spool is in direct contact with a wall of the bore defined within the valve housing as opposed to utilization of a sleeve interposed between the wall of the bore and the spool valve. A pressure equalizing passageway is connected between the pressure passageways for the purpose of substantially reducing pressure drop when the spool valve translates to allow flow of fluid through the valve.
    Type: Grant
    Filed: January 27, 1994
    Date of Patent: April 2, 1996
    Assignee: HR Textron Inc.
    Inventor: Alvon C. Elrod, Jr.
  • Patent number: 5417186
    Abstract: An apparatus and method effects the cyclical actuation of an actuation member. The apparatus can be driven by a crankshaft and has at least one dual-acting phasing apparatus with at least three rotatable mounted internally splined members and at least a first rotatably mounted, externally splined, flexible member having a portion thereof rotatably disposed within each of at least two of the internally splined members. One inner splined member can be connected nonrotatably to a first rotatable member such as an inner shaft, which is rotatably disposed within an outer shaft of a concentric camshaft. Another internally splined member can be nonrotatably connected to the outer shaft. Yet another internally splined member can be nonrotatably connected to a pulley wheel driven by the crankshaft. A fourth internally splined member can be connected to one of the other three internally splined members.
    Type: Grant
    Filed: June 28, 1993
    Date of Patent: May 23, 1995
    Assignee: Clemson University
    Inventors: Alvon C. Elrod, Michael T. Nelson
  • Patent number: 5285715
    Abstract: An electrohydraulic servovalve including a tailoring circuit coupled to provide a predetermined input signal to the motor of the valve. The predetermined signal functions to control the flow of fluid from the valve to effect a desired result. The electrohydraulic servovalve includes a housing defining round flow ports with a spool valve for metering flow through the ports. The spool valve substantially overlaps the round flow ports. The tailoring circuit includes a plurality of amplifiers each of which has a different gain. A command signal is applied to the amplifier and the output from the amplifiers is summed to provide an input signal to the motor of the electrohydraulic servovalve.
    Type: Grant
    Filed: August 6, 1992
    Date of Patent: February 15, 1994
    Assignee: HR Textron, Inc.
    Inventors: Alvon C. Elrod, Jr., Robert C. Heagey, Donald C. Muths, Larry L. Nichols, Clyde E. Cobb
  • Patent number: 5253546
    Abstract: An actuating apparatus, which can be used to perform variable valve timing of the intake or exhaust valves of an internal combustion engine, includes a hollow shaft with at least one slot defined through a cylindrical wall. A movable cam member is disposed to project through the slot and is rotatable relative to the hollow shaft in a channel defined in the interior surface of the hollow shaft. A base circle band extends circumferentially around the outer surface of the hollow shaft between the endwalls of the slot. The exterior surface of the hollow shaft can define grooves which receive front or back ear members of the cam member. The exterior surface of the hollow shaft also can define recesses, which in some embodiments have bottom surfaces and in other embodiments have partial bottom surfaces or no bottom surface. The recesses can receive tongue members formed on the cam member. The cam member can be engaged by a cam follower that has a roller to engage the cam surface.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: October 19, 1993
    Assignee: Clemson University
    Inventors: Alvon C. Elrod, Michael T. Nelson
  • Patent number: 5161429
    Abstract: An actuating apparatus, which can be used to perform variable valve timing of the intake or exhaust valves of an internal combustion engine, includes a hollow shaft with at least one slot defined through a cylindrical wall. A movable cam member is disposed to project through the slot and is rotatable relative to the hollow shaft in a channel defined in the interior surface of the hollow shaft. A base circle band extends circumferentially around the outer surface of the hollow shaft between the endwalls of the slot. The exterior surface of the hollow shaft can define grooves which receive front or back ear members of the cam member. The exterior surface of the hollow shaft also can define recesses, which in some embodiments have bottom surfaces and in other embodiments have partial bottom surfaces or no bottom surface. The recesses can receive tongue members formed on the cam member. The cam member can be engaged by a cam follower that has a roller to engage the cam surface.
    Type: Grant
    Filed: January 29, 1992
    Date of Patent: November 10, 1992
    Assignee: Clemson University
    Inventors: Alvon C. Elrod, Michael T. Nelson
  • Patent number: 5136887
    Abstract: An actuating apparatus, which can be used to perform variable valve timing of the intake or exhaust valves of an internal combustion engine, includes a hollow shaft with at least one slot defined through a cylindrical wall. A movable cam member is disposed to project through the slot and is rotatable relative to the hollow shaft in a channel defined in the interior surface of the hollow shaft. A base circle band extends circumferentially around the outer surface of the hollow shaft between the endwalls of the slot. The exterior surface of the hollow shaft can define grooves which receive front or back ear members of the cam member. The exterior surface of the hollow shaft also can define recesses, which in some embodiments have bottom surfaces and in other embodiments have partial bottom surfaces or no bottom surface. The recesses can receive tongue members formed on the cam member. The cam member can be engaged by a cam follower that has a roller to engage the cam surface.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: August 11, 1992
    Assignee: Clemson University
    Inventors: Alvon C. Elrod, Michael T. Nelson
  • Patent number: 4917058
    Abstract: A method is provided for improving the performance of an internal combustion engine, comprising the steps of inducting a charge of fluid into the combustion chamber of the engine, holding the intake valve of the combustion chamber open during a portion of the compression stroke of the piston in the combustion chamber, expelling a portion of the inducted charge from the combustion chamber by movement of the piston in its compression stroke while the intake valve is held open, preventing the expelled portion of the inducted charge from communicating with the atmosphere by providing a check valve between the induction manifold and the atmosphere, the check valve only permitting flow in the direction from the atmosphere into the induction manifold; and closing the intake valve during the remainder of the compression stroke and after the portion of the induction charge is expelled.
    Type: Grant
    Filed: April 18, 1988
    Date of Patent: April 17, 1990
    Assignee: Clemson University
    Inventors: Michael T. Nelson, Alvon C. Elrod
  • Patent number: 4771742
    Abstract: A method of attaining a desired engine performance comprises the steps of changing the angular position of a variable camlobe (or cam) member relative to a fixed camlobe (or cam) member from a first angular position to a second angular position. In changing from the first to the second angular position, the variable camlobe (or cam) member moves in a predetermined direction relative to the direction of rotation of a camshaft. The predetermined direction and the magnitude of the angular movement of the variable camlobe (or cam) member is dependent at least in part upon at least one desired operating condition of the engine. The method further comprises changing the angular position of both camlobe (or cam) members relative to a reference point of a drive pulley. This change in the angular position of both of the camlobe (or cam) members relative to the reference point involves movement of the camlobes (or cams) in a direction relative to the direction of rotation of a camshaft.
    Type: Grant
    Filed: January 15, 1987
    Date of Patent: September 20, 1988
    Assignee: Clemson University
    Inventors: Michael T. Nelson, Alvon C. Elrod
  • Patent number: 4770060
    Abstract: An apparatus for cyclically actuating an actuation member comprises a hollow shaft rotatable about an axis of rotation and defining therein a cam opening therethrough, an inner shaft rotatably carried within the hollow shaft, a cam member fixed to the hollow shaft adjacent the cam opening, a cam member fixed to the inner shaft and projecting through the cam opening of the hollow shaft, a variable transmission having a reference element connected to one of the shafts and an output element connected to the other of the shafts, and an input element; a pulley wheel connected to the shafts for rotating same about the axis, and an electric motor connected to the input element of the variable transmission for rotating same, the electric motor being controlled by an electronic control unit which can include one or more microprocessor units.
    Type: Grant
    Filed: February 19, 1986
    Date of Patent: September 13, 1988
    Assignee: Clemson University
    Inventors: Alvon C. Elrod, Nelson, Michael T.