Patents by Inventor John C. Hedrick

John C. Hedrick 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: 10837385
    Abstract: A method of raising exhaust gas temperatures of a two-cycle uniflow scavenged engine at lower loads. At lower loads, the exhaust valves are activated with a frequency that is less frequent than every engine cycle. This retains exhaust within the cylinder for one or more cycles, and when the exhaust valves are again activated, the exhaust temperature will be elevated. For engines having a means for controlling intake manifold pressure, such as a compressor having variable speed or a means for bleeding off compressor output, intake manifold pressure can be reduced at low loads, which also has the effect of elevating exhaust temperatures.
    Type: Grant
    Filed: May 21, 2018
    Date of Patent: November 17, 2020
    Assignee: Yelir, Inc.
    Inventors: Michael B. Riley, John C. Hedrick, Steven G. Fritz
  • Patent number: 10690045
    Abstract: An air boost system for a two-cycle engine, such as an EMD engine, which operates with one or more roots blowers, or for similar engines that use gear-driven roots blowers or centrifugal blowers. At least one of the roots blowers is equipped with a variable transmission, which allows airflow into the engine to be varied in accordance with load or other engine operating conditions.
    Type: Grant
    Filed: March 5, 2017
    Date of Patent: June 23, 2020
    Assignee: Southwest Research Institute
    Inventors: John C. Hedrick, Steven G. Fritz, Randy R. McDonnell
  • Publication number: 20190353113
    Abstract: A method of raising exhaust gas temperatures of a two-cycle uniflow scavenged engine at lower loads. At lower loads, the exhaust valves are activated with a frequency that is less frequent than every engine cycle. This retains exhaust within the cylinder for one or more cycles, and when the exhaust valves are again activated, the exhaust temperature will be elevated. For engines having a means for controlling intake manifold pressure, such as a compressor having variable speed or a means for bleeding off compressor output, intake manifold pressure can be reduced at low loads, which also has the effect of elevating exhaust temperatures.
    Type: Application
    Filed: May 21, 2018
    Publication date: November 21, 2019
    Inventors: Michael B. Riley, John C. Hedrick, Steven G. Fritz
  • Patent number: 10428707
    Abstract: A system and method for particulate matter reduction. A diesel particulate filtration system includes an inlet, an outlet, an exhaust path between the inlet and the outlet, a diesel particulate filter positioned in the exhaust path between the inlet and the outlet, and a bypass valve, wherein the diesel particulate filtration system is configured to have a diesel engine operatively coupled to the inlet. The bypass valve being configured to open when a maximum allowable engine backpressure is exceeded. When the bypass valve is closed, exhaust gas including particulate matter passes through the diesel particulate filter. When the bypass valve is open, a portion of the exhaust gas passes through the diesel particulate filter and the remainder of the exhaust gas passes through the bypass valve and at least 40 percent of said particulate matter is removed from said exhaust gas.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: October 1, 2019
    Assignee: Southwest Research Institute
    Inventors: Steven G. Fritz, John C. Hedrick
  • Publication number: 20180252153
    Abstract: An air boost system for a two-cycle engine, such as an EMD engine, which operates with one or more roots blowers, or for similar engines that use gear-driven roots blowers or centrifugal blowers. At least one of the roots blowers is equipped with a variable transmission, which allows airflow into the engine to be varied in accordance with load or other engine operating conditions.
    Type: Application
    Filed: March 5, 2017
    Publication date: September 6, 2018
    Inventors: John C. Hedrick, Steven G. Fritz, Randy R. McDonnell
  • Patent number: 9995206
    Abstract: An air boost system for a two-cycle engine, such as an EMD engine, which operates with a gear-driven turbo-supercharger. The turbo-supercharger is undersized for the engine, such that it is insufficient to provide air flow for a target air-fuel ratio above a pre-determined mid-load threshold. An additional turbocharger is installed in parallel with the turbo-supercharger, such that the intake manifold may receive air intake from only the turbo-supercharger or from both the turbo-supercharger and the turbocharger. In operation, the turbocharger is active only at loads above the predetermined load threshold.
    Type: Grant
    Filed: April 8, 2016
    Date of Patent: June 12, 2018
    Assignee: SOUTHWEST RESEARCH INSTITUTE
    Inventors: John C. Hedrick, Steven G. Fritz
  • Patent number: 9803571
    Abstract: A method, used with dual-fuel engine, of controlling the amount of gaseous fuel delivered to the engine. At operating conditions that result in an equivalence ratio below a predetermined threshold (which typically occur at mid or part loads), it is determined whether better performance and/or lower emissions can be achieved by reducing gaseous fuel to some cylinders and increasing gaseous fuel to others. Typically, the gaseous fuel is reduced to zero to a number of cylinders and increased to others, with the increase resulting in an equivalence ratio that will provide improved emissions and efficiency and the desired engine output.
    Type: Grant
    Filed: January 23, 2016
    Date of Patent: October 31, 2017
    Assignee: SOUTHWEST RESEARCH INSTITUTE
    Inventors: John C. Hedrick, David P. Branyon, Timothy J. Callahan, Jeremy D. Eubanks, Ryan C. Roecker, Garrett L. Anderson
  • Publication number: 20170292438
    Abstract: An air boost system for a two-cycle engine, such as an EMD engine, which operates with a gear-driven turbo-supercharger. The turbo-supercharger is undersized for the engine, such that it is insufficient to provide air flow for a target air-fuel ratio above a pre-determined mid-load threshold. An additional turbocharger is installed in parallel with the turbo-supercharger, such that the intake manifold may receive air intake from only the turbo-supercharger or from both the turbo-supercharger and the turbocharger. In operation, the turbocharger is active only at loads above the predetermined load threshold.
    Type: Application
    Filed: April 8, 2016
    Publication date: October 12, 2017
    Inventors: John C. Hedrick, Steven G. Fritz
  • Publication number: 20170211490
    Abstract: A method, used with dual-fuel engine, of controlling the amount of gaseous fuel delivered to the engine. At operating conditions that result in an equivalence ratio below a predetermined threshold (which typically occur at mid or part loads), it is determined whether better performance and/or lower emissions can be achieved by reducing gaseous fuel to some cylinders and increasing gaseous fuel to others. Typically, the gaseous fuel is reduced to zero to a number of cylinders and increased to others, with the increase resulting in an equivalence ratio that will provide improved emissions and efficiency and the desired engine output.
    Type: Application
    Filed: January 23, 2016
    Publication date: July 27, 2017
    Inventors: John C. Hedrick, David P. Branyon, Timothy J. Callahan, Jeremy D. Eubanks, Ryan C. Roecker, Garrett L. Anderson
  • Publication number: 20150240681
    Abstract: A system and method for particulate matter reduction. A diesel particulate filtration system includes an inlet, an outlet, an exhaust path between the inlet and the outlet, a diesel particulate filter positioned in the exhaust path between the inlet and the outlet, and a bypass valve, wherein the diesel particulate filtration system is configured to have a diesel engine operatively coupled to the inlet. The bypass valve being configured to open when a maximum allowable engine backpressure is exceeded. When the bypass valve is closed, exhaust gas including particulate matter passes through the diesel particulate filter. When the bypass valve is open, a portion of the exhaust gas passes through the diesel particulate filter and the remainder of the exhaust gas passes through the bypass valve and at least 40 percent of said particulate matter is removed from said exhaust gas.
    Type: Application
    Filed: February 25, 2014
    Publication date: August 27, 2015
    Inventors: Steven G. FRITZ, John C. HEDRICK
  • Patent number: 7059278
    Abstract: A locomotive engine having an engine cooling system, a compressor for compressing engine intake air, and an aftercooler for cooling the compressed intake air prior to introduction into an intake manifold of the engine. The locomotive also has a dynamic brake system that includes a dynamic brake grid and one or more cooling fans. The engine cooling system includes an engine cooling circuit having coolant passages internally disposed in the engine, and a radiator and radiator fans configured to receive coolant exiting the engine and return cooled coolant to the engine. An enhanced aftercooler cooling circuit is disposed in fluid communication with the engine cooling circuit and includes a heat exchanger arranged to receive coolant exiting the engine coolant passages, cool the coolant passing therethrough, and return cooled coolant to the aftercooler.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: June 13, 2006
    Assignee: Southwest Research Institute
    Inventors: John C. Hedrick, Steven G. Fritz
  • Patent number: 6990857
    Abstract: A fuel injector timing tool has an elongated tubular member on which a measurement device may be mounted. A lower end of the tubular member is attached to a base member disposed perpendicularly to the tubular member and has an open end that only partially circumscribes a plunger follower slidably disposed on a retainer element of the fuel injector. The timing tool permits ready access to an adjustable ball stud and associated lock nut mounted in a plunger actuator end of an injector rocker arm so that accurate plunger position can be set while the timing tool remains in place on the retainer element of the fuel injector.
    Type: Grant
    Filed: August 26, 2004
    Date of Patent: January 31, 2006
    Assignee: Southwest Research Institute
    Inventors: Gary D. Bourn, John C. Hedrick, Steven G. Fritz, Larry W. Wolter
  • Patent number: 6494192
    Abstract: An on-board fuel vapor recovery system draws vapors from a fuel tank, compresses the vapors, and then cools the compressed vapors to form a condensate liquid fuel which is stored in an auxiliary condensate tank for introduction to an engine for enhanced cold start operation.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: December 17, 2002
    Assignee: Southwest Research Institute
    Inventors: William K. Capshaw, John C. Hedrick, David W. Naegeli, Michael G. Ross
  • Publication number: 20020185115
    Abstract: An on-board fuel vapor recovery system draws vapors from a fuel tank, compresses the vapors, and then cools the compressed vapors to form a condensate liquid fuel which is stored in an auxiliary condensate tank for introduction to an engine for enhanced cold start operation.
    Type: Application
    Filed: June 12, 2001
    Publication date: December 12, 2002
    Inventors: William K. Capshaw, John C. Hedrick, David W. Naegeli, Michael G. Ross
  • Patent number: 6227174
    Abstract: An electronically controlled unit injector for internal combustion engine. The unit injector is mounted on a cylinder and has a plunger that extends into the combustion chamber. Fuel flow through the unit injector is accomplished by the plunger, which moves upward into the unit injector in response to upward motion of the piston. This motion displaces fuel and pressurizes a fuel path within the unit injector, including a pressure void at the tip of the needle. The pressurized fuel lifts the needle, which permits fuel to exit through injection spray holes into the combustion chamber.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: May 8, 2001
    Assignee: Southwest Research Institute
    Inventors: John C. Hedrick, Robert W. Burrahm
  • Patent number: 6062178
    Abstract: A method of operating a two-cycle internal combustion engine under low load conditions. A throttle is placed at the intake air system to reduce air intake into the engine cylinders. A pump is placed in the exhaust system, such that it creates reduced pressure downstream of the exhaust valves. In this manner, when the air intake ports close, the exhaust is evacuated and the air trapped in the cylinder is reduced. This permits fuel to be reduced so that the engine may operate in a low load state without losing combustion.
    Type: Grant
    Filed: May 20, 1998
    Date of Patent: May 16, 2000
    Assignee: Southwest Research Institute
    Inventors: David P. Meyers, John C. Hedrick, Gary D. Bourn, John T. Kubesh, Kevin D. Beaty, Robert W. Burrahm
  • Patent number: 5890459
    Abstract: A standard diesel injection system and a mechanical direct-gas injection system are selectively operable, in combination with a continuous pilot injection system, to provide a combustion system that is capable of operating in either a conventional diesel mode or a dual-fuel mode. Operation between convention diesel or dual-fuel combustion modes is mechanically controlled by a two-position, four-way control valve. The mechanical direct-gas injection system is actuated by pulsed diesel fuel directed to the actuation chamber of a gas injector by the same injection pump used to provide diesel fuel to the combustion chamber during conventional diesel operation.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: April 6, 1999
    Assignee: Southwest Research Institute
    Inventors: John C. Hedrick, Gary Bourn