Patents by Inventor Homa Afjeh
Homa Afjeh 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).
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Patent number: 8689769Abstract: A method is disclosed for controlling compression-braking performance of an engine having a piston in a combustion cylinder. The method may include providing a valve in fluid communication with the combustion cylinder and at least one valve actuator operable to control the valve to perform compression-braking by opening the valve, which may include opening the valve to a first peak-valve-opening during a compression stroke of the piston and opening the valve to a second peak-valve-opening before a second half of an expansion stroke of the piston. The method may also include determining a target value for a stress in the at least one valve actuator. Additionally, the method may include designing the magnitude and timing of the first peak-valve-opening as a function of the target for the stress in the at least one valve actuator.Type: GrantFiled: May 12, 2010Date of Patent: April 8, 2014Assignee: Caterpillar Inc.Inventors: Homa Afjeh, Edwin Henry Langewisch
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Publication number: 20120067331Abstract: A power system comprising an engine, an intake air system, and an intake air bypass system. The intake air system delivers compressed air to the engine and the intake air bypass system diverts the compressed air away from the engine in response to the operation of an engine brake.Type: ApplicationFiled: September 16, 2010Publication date: March 22, 2012Applicant: Caterpillar Inc.Inventors: John S. Pipis, JR., Homa Afjeh
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Publication number: 20110289914Abstract: A power system comprising an engine that produces exhaust and includes an exhaust gas recirculation (EGR) system. The EGR system includes an EGR conduit routing an exhaust flow back to the engine, a restriction valve disposed in the EGR conduit, and a control valve disposed in the EGR conduit in series with the restriction valve.Type: ApplicationFiled: May 28, 2010Publication date: December 1, 2011Applicant: Caterpillar Inc.Inventor: Homa Afjeh
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Publication number: 20110277729Abstract: A method is disclosed for controlling compression-braking performance of an engine having a piston in a combustion cylinder. The method may include providing a valve in fluid communication with the combustion cylinder and at least one valve actuator operable to control the valve to perform compression-braking by opening the valve, which may include opening the valve to a first peak-valve-opening during a compression stroke of the piston and opening the valve to a second peak-valve-opening before a second half of an expansion stroke of the piston. The method may also include determining a target value for a stress in the at least one valve actuator. Additionally, the method may include designing the magnitude and timing of the first peak-valve-opening as a function of the target for the stress in the at least one valve actuator.Type: ApplicationFiled: May 12, 2010Publication date: November 17, 2011Inventors: Homa Afjeh, Edwin Henry Langewisch
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Patent number: 7441519Abstract: An engine valve actuation system may include an intake valve moveable between a first position that blocks a flow of fluid and a second position that allows a flow of fluid. The system may also include a cam assembly configured to move the intake valve between the first position and the second position. An electromagnetic actuator may be configured to selectively modify a timing of the intake valve in moving from the second position to the first position.Type: GrantFiled: December 23, 2005Date of Patent: October 28, 2008Assignee: Caterpillar Inc.Inventors: Homa Afjeh, Ronald D. Shinogle, Gregory D. Brock, Scott A. Leman
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Patent number: 7191743Abstract: In one aspect, the present disclosure is directed to an internal combustion engine having an engine block defining at least one cylinder and a head connected with said engine block. The head has an air intake port and an exhaust port. The internal combustion engine also has a piston and a combustion chamber. The internal combustion engine further has an air intake valve movable to open and close the air intake port and an air supply system having at least one turbocharger fluidly connected to the air intake port. The internal combustion engine additionally has a fuel supply system operable to inject fuel into the combustion chamber, a cam assembly selectively mechanically linked to the air intake valve to move the air intake valve, and an electromagnetic actuator configured to decouple the cam assembly from the air intake valve and control movement of the air intake valve.Type: GrantFiled: November 19, 2004Date of Patent: March 20, 2007Assignee: Caterpillar IncInventors: James R. Weber, Scott A. Leman, Gerald N. Coleman, Kevin P. Duffy, Eric C. Fluga, Jonathan P. Kilkenny, Homa Afjeh
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Publication number: 20060096560Abstract: An engine valve actuation system may include an intake valve moveable between a first position that blocks a flow of fluid and a second position that allows a flow of fluid. The system may also include a cam assembly configured to move the intake valve between the first position and the second position. An electromagnetic actuator may be configured to selectively modify a timing of the intake valve in moving from the second position to the first position.Type: ApplicationFiled: December 23, 2005Publication date: May 11, 2006Inventors: Homa Afjeh, Ronald Shinogle, Gregory Brock, Scott Leman
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Patent number: 7007643Abstract: An engine valve actuation system may include an intake valve moveable between a first position that blocks a flow of fluid and a second position that allows a flow of fluid. The system may also include a cam assembly configured to move the intake valve between the first position and the second position. An electromagnetic actuator may be configured to selectively modify a timing of the intake valve in moving from the second position to the first position.Type: GrantFiled: October 31, 2003Date of Patent: March 7, 2006Assignee: Caterpillar Inc.Inventors: Homa Afjeh, Ronald D. Shinogle, Gregory D. Brock, Scott A. Leman
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Publication number: 20050241611Abstract: In one aspect, the present disclosure is directed to an internal combustion engine having an engine block defining at least one cylinder and a head connected with said engine block. The head has an air intake port and an exhaust port. The internal combustion engine also has a piston and a combustion chamber. The internal combustion engine further has an air intake valve movable to open and close the air intake port and an air supply system having at least one turbocharger fluidly connected to the air intake port. The internal combustion engine additionally has a fuel supply system operable to inject fuel into the combustion chamber, a cam assembly selectively mechanically linked to the air intake valve to move the air intake valve, and an electromagnetic actuator configured to decouple the cam assembly from the air intake valve and control movement of the air intake valve.Type: ApplicationFiled: November 19, 2004Publication date: November 3, 2005Inventors: James Weber, Scott Leman, Gerald Coleman, Kevin Duffy, Eric Fluga, Jonathan Kilkenny, Homa Afjeh
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Publication number: 20050133003Abstract: A compression release brake system 10 includes a hydraulic apparatus 12 for controllably opening at least one exhaust valve 14 of at least one cylinder 16 of an engine in response to motion of a cam actuator 12. The system 10 includes a master piston assembly 40 having a master piston 42 engageable with the cam actuator 12. The master piston 42 includes a compressible piston pin 56. A slave piston assembly 44 is hydraulically linked to the master piston assembly 40 and includes a slave piston 46 engageable with the at least one exhaust valve 14.Type: ApplicationFiled: December 18, 2003Publication date: June 23, 2005Inventors: Homa Afjeh, Mark Ellison, John Pipis
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Patent number: 6904892Abstract: A compression release brake system 10 includes a hydraulic apparatus 12 for controllably opening at least one exhaust valve 14 of at least one cylinder 16 of an engine in response to motion of a cam actuator 12. The system 10 includes a master piston assembly 40 having a master piston 42 engageable with the cam actuator 12. The master piston 42 includes a compressible piston pin 56. A slave piston assembly 44 is hydraulically linked to the master piston assembly 40 and includes a slave piston 46 engageable with the at least one exhaust valve 14.Type: GrantFiled: December 18, 2003Date of Patent: June 14, 2005Assignee: Caterpillar IncInventors: Homa Afjeh, Mark S. Ellison, John S. Pipis
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Publication number: 20040123824Abstract: An engine valve actuation system may include an intake valve moveable between a first position that blocks a flow of fluid and a second position that allows a flow of fluid. The system may also include a cam assembly configured to move the intake valve between the first position and the second position. An electromagnetic actuator may be configured to selectively modify a timing of the intake valve in moving from the second position to the first position.Type: ApplicationFiled: October 31, 2003Publication date: July 1, 2004Applicant: Caterpillar, Inc.Inventors: Homa Afjeh, Ronald D. Shinogle, Gregory D. Brook, Scott A. Leman
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Publication number: 20040083994Abstract: A system for actuating a valve element in an engine valve assembly of an internal combustion engine is provided. The system has a first piston that includes a first rod and is disposed in a first chamber. The system also includes a second piston that has a second rod with an end being separated from the engine valve assembly by a predetermined distance. The second piston is disposed in a second chamber that is in fluid connection with the first chamber such that movement of the first piston causes a corresponding movement of the second piston. A cam having a cam lobe is operatively engaged with the first rod such that rotation of the cam and cam lobe moves the first piston to thereby move the second piston. The cam lobe has a shape adapted to cause the second rod to move through the predetermined distance and to engage the engine valve assembly to move the valve element at a predetermined point in the operating cycle of the internal combustion engine.Type: ApplicationFiled: July 2, 2003Publication date: May 6, 2004Inventors: Homa Afjeh, Scott A. Leman, Clifford Cotton