Patents by Inventor Shriprasad G. Lakhapati

Shriprasad G. Lakhapati 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: 8505514
    Abstract: A common rail single fluid injection system including fuel injectors with the ability to produce multiple injection rate shapes. This is accomplished by including auxiliary filling orifices which selectively provide pressurized fluid to the check needle control chamber during injection events. In so doing, the speed and movement of the check needle is manipulated and differing injection rates may be achieved.
    Type: Grant
    Filed: March 9, 2010
    Date of Patent: August 13, 2013
    Assignee: Caterpillar Inc.
    Inventors: Dianqi Fang, Lin Zhang, Stephen Robert Lewis, Zhenlong Xu, Avinash R. Manubolu, Shriprasad G. Lakhapati, Christopher D. Hanson
  • Patent number: 8459577
    Abstract: A valve assembly including an armature and a valve member that are coupled when the solenoid coil is de-energized but are decoupled after the solenoid coil is energized. A first spring biases the armature and the valve member to a closed valve seat position while a second spring having a smaller preload than the first spring biases the valve member to an open valve seat position. When the solenoid coil is energized, the magnetic force of the coil overcomes the force exerted by the first spring pulling the armature away from the valve member. The valve member moves to the open valve seat position by the force exerted by the second spring. When the coil is de-energized, the magnetic force decays, thereby allowing the armature and the valve member to re-couple.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: June 11, 2013
    Assignee: Caterpillar Inc.
    Inventors: Avinash R. Manubolu, Shriprasad G. Lakhapati, Stephen Lewis, Christopher D. Hanson
  • Publication number: 20120067981
    Abstract: A solenoid actuator includes a hard guide piece and a soft flux piece. The hard guide piece has a stop surface ground to create a final air gap distance between the soft flux piece and a stator assembly when the stop surface on the guide piece is in contact with the stator assembly. The final air gap is set by grinding the stop surface on the guide piece so that the distance between the stop surface on the guide piece and a top surface on the soft flux piece along an axis of the guide bore is equal to the final air gap. The step of grinding the armature assembly may be done after attaching the guide piece and the flux piece together. In an exemplary embodiment, the step of grinding the stop surface and associated guide surface(s) are performed in a single chucking.
    Type: Application
    Filed: November 29, 2011
    Publication date: March 22, 2012
    Applicant: CATERPILLAR INC.
    Inventors: Avinash R. Manubolu, Shriprasad G. Lakhapati, Stephen R. Lewis, Daniel R. Ibrahim
  • Patent number: 8083206
    Abstract: A solenoid actuator includes a hard guide piece and a soft flux piece. The hard guide piece has a stop surface ground to create a final air gap distance between the soft flux piece and a stator assembly when the stop surface on the guide piece is in contact with the stator assembly. The final air gap is set by grinding the stop surface on the guide piece so that the distance between the stop surface on the guide piece and a top surface on the soft flux piece along an axis of the guide bore is equal to the final air gap. The step of grinding the armature assembly may be done after attaching the guide piece and the flux piece together. In an exemplary embodiment, the step of grinding the stop surface and associated guide surface(s) are performed in a single chucking.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: December 27, 2011
    Assignee: Caterpillar Inc.
    Inventors: Avinash R. Manubolu, Shriprasad G. Lakhapati, Stephen R. Lewis, Daniel R. Ibrahim
  • Publication number: 20110220064
    Abstract: A common rail single fluid injection system including fuel injectors with the ability to produce multiple injection rate shapes. This is accomplished by including auxiliary filling orifices which selectively provide pressurized fluid to the check needle control chamber during injection events. In so doing, the speed and movement of the check needle is manipulated and differing injection rates may be achieved.
    Type: Application
    Filed: March 9, 2010
    Publication date: September 15, 2011
    Applicant: Caterpillar Inc.
    Inventors: Dianqi Fang, Lin Zhang, Stephen Robert Lewis, Zhenlong Xu, Avinash R. Manubolu, Shriprasad G. Lakhapati, Christopher D. Hanson
  • Patent number: 7980224
    Abstract: A fuel system includes a plurality of fuel injectors fluidly connected to a common rail. Each of the fuel injectors has at least one body component and includes an intensifier control valve for controlling movement of an intensifier piston, a needle control valve for controlling movement of a needle valve member, and exactly one electrical actuator coupled with the intensifier control valve and the needle control valve via a coupling linkage. The intensifier control valve and the needle control valve each include a valve member that is movable with respect to a valve seat. The electrical actuator includes an intermediate position during which the valve member of one of the intensifier control valve and the needle control valve is in contact with the respective valve seat, and the valve member of the other of the intensifier control valve and the needle control valve is out of contact with the respective valve seat.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: July 19, 2011
    Assignee: Caterpillar Inc.
    Inventors: Stephen R. Lewis, Bradley E. Bartley, Avinash R. Manubolu, Shriprasad G. Lakhapati, Dianqi Fang, Michael Gerstner, Christopher D. Hanson, Jeffrey M. Mullinix
  • Patent number: 7886718
    Abstract: A fuel injector includes a body piece that defines a nozzle supply passage and a chamber in fluid communication therewith and configured to contain a fluid pressure within the fuel injector. The body piece has a threaded segment and a second, unthreaded segment that includes an outer surface of the fuel injector. A tip piece is clamped via a clamping piece to the body piece to form a fluid seal therewith, and a needle check extends within the body piece and the tip piece. The body piece is configured to contain fluid pressures, for example up to and exceeding 200 MPa, and has a wall thickness between the chamber and the unthreaded segment that is linked to a fluid pressure of fuel passing through the chamber. The fuel injector is configured via integrating portions of a nozzle case and a body guide to contain the extremely high fuel pressures.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: February 15, 2011
    Assignee: Caterpillar Inc.
    Inventors: Avinash R. Manubolu, Stephen R. Lewis, Shriprasad G. Lakhapati, Zhenlong Xu
  • Publication number: 20100077994
    Abstract: A fuel injector includes a body piece that defines a nozzle supply passage and a chamber in fluid communication therewith and configured to contain a fluid pressure within the fuel injector. The body piece has a threaded segment and a second, unthreaded segment that includes an outer surface of the fuel injector. A tip piece is clamped via a clamping piece to the body piece to form a fluid seal therewith, and a needle check extends within the body piece and the tip piece. The body piece is configured to contain fluid pressures, for example up to and exceeding 200 MPa, and has a wall thickness between the chamber and the unthreaded segment that is linked to a fluid pressure of fuel passing through the chamber. The fuel injector is configured via integrating portions of a nozzle case and a body guide to contain the extremely high fuel pressures.
    Type: Application
    Filed: September 26, 2008
    Publication date: April 1, 2010
    Inventors: Avinash R. Manubolu, Stephen R. Lewis, Shriprasad G. Lakhapati, Zhenlong Xu
  • Publication number: 20100005646
    Abstract: A solenoid actuator includes a hard guide piece and a soft flux piece. The hard guide piece has a stop surface ground to create a final air gap distance between the soft flux piece and a stator assembly when the stop surface on the guide piece is in contact with the stator assembly. The final air gap is set by grinding the stop surface on the guide piece so that the distance between the stop surface on the guide piece and a top surface on the soft flux piece along an axis of the guide bore is equal to the final air gap. The step of grinding the armature assembly may be done after attaching the guide piece and the flux piece together. In an exemplary embodiment, the step of grinding the stop surface and associated guide surface(s) are performed in a single chucking.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 14, 2010
    Inventors: Avinash R. Manubolu, Shriprasad G. Lakhapati, Stephen R. Lewis, Daniel R. Ibrahim
  • Publication number: 20100006679
    Abstract: A valve assembly including an armature and a valve member that are coupled when the solenoid coil is de-energized but are decoupled after the solenoid coil is energized. A first spring biases the armature and the valve member to a closed valve seat position while a second spring having a smaller preload than the first spring biases the valve member to an open valve seat position. When the solenoid coil is energized, the magnetic force of the coil overcomes the force exerted by the first spring pulling the armature away from the valve member. The valve member moves to the open valve seat position by the force exerted by the second spring. When the coil is de-energized, the magnetic force decays, thereby allowing the armature and the valve member to re-couple.
    Type: Application
    Filed: July 8, 2008
    Publication date: January 14, 2010
    Inventors: Avinash R. Manubolu, Shriprasad G. Lakhapati, Stephen Lewis, Christopher D. Hanson
  • Publication number: 20090194072
    Abstract: A fuel system includes a plurality of fuel injectors fluidly connected to a common rail. Each of the fuel injectors has at least one body component and includes an intensifier control valve for controlling movement of an intensifier piston, a needle control valve for controlling movement of a needle valve member, and exactly one electrical actuator coupled with the intensifier control valve and the needle control valve via a coupling linkage. The intensifier control valve and the needle control valve each include a valve member that is movable with respect to a valve seat. The electrical actuator includes an intermediate position during which the valve member of one of the intensifier control valve and the needle control valve is in contact with the respective valve seat, and the valve member of the other of the intensifier control valve and the needle control valve is out of contact with the respective valve seat.
    Type: Application
    Filed: February 3, 2009
    Publication date: August 6, 2009
    Inventors: Stephen R. Lewis, Bradley E. Bartley, Avinash R. Manubolu, Shriprasad G. Lakhapati, Dianqi Fang, Michael Gerstner, Christopher D. Hanson, Jeffrey M. Mullinix