Patents by Inventor Robert C. Yu

Robert C. Yu 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: 11945900
    Abstract: The present disclosure provides an orthodontic article including the reaction product of the polymerizable composition. Further, the present disclosure provides polymerizable compositions and methods of making an orthodontic article. The method includes obtaining a polymerizable composition and selectively curing the polymerizable composition to form an orthodontic article. Further, methods are provided, including receiving, by a manufacturing device having one or more processors, a digital object comprising data specifying an orthodontic article; and generating, with the manufacturing device by an additive manufacturing process, the orthodontic article based on the digital object. A system is also provided, including a display that displays a 3D model of an orthodontic article; and one or more processors that, in response to the 3D model selected by a user, cause a 3D printer to create a physical object of an orthodontic article.
    Type: Grant
    Filed: June 27, 2019
    Date of Patent: April 2, 2024
    Assignee: 3M Innovative Properties Company
    Inventors: Thomas P. Klun, Zeba Parkar, John M. Riedesel, Richard J. Pokorny, Chad M. Amb, Benjamin R. Coonce, Robert S. Clough, Tianyu Wu, Saswata Chakraborty, Yongshang Lu, Benjamin C. MacMurray, Ahmed S. Abuelyaman, Karl J. L. Geisler, Jodi L. Connell, Ta-Hua Yu
  • Publication number: 20130263820
    Abstract: An integrated lean burn stabilizer (ILBS) for initiating combustion in an internal combustion engine by generating and introducing active free radicals into a combustion chamber is provided. Engines equipped with the ILBS can achieve a fuel efficient clean combustion processes with a lean and/or diluted mixture otherwise incapable of auto ignition and provide a controlled start of combustion, in conjunction with early in-cylinder direct injection, late diesel-like in-cylinder direct injection, and mixed fuel functions allowing control of the composition and stratification of the mixture. Controlled aspects of the fuel mixture include the equivalent ratio and fuel reactivity combinations inside the main combustion chamber, thereby allowing the start of combustion and duration of combustion inside the main combustion chamber be optimized for maximum cycle efficiency and specific power output while minimizing emissions.
    Type: Application
    Filed: April 8, 2013
    Publication date: October 10, 2013
    Inventors: Robert C. Yu, Ming-Li Hsu Yu, Robert C. Yu, JR.
  • Patent number: 7900441
    Abstract: The invention provides a NOx adsorber aftertreatment system for internal combustion engines which utilizes at least one precat operatively coupled to at least one NOx adsorber to aid in the regeneration of the NOx adsorber. Fuel is injected into a precat located upstream of a NOx absorber producing heat, H2O, and reductants such as CO, HC, and volatile hydrocarbons, which are input into the NOx absorber. The combination of heat, water, and reductants help to efficiently regenerate the NOx Adsorber which in turn releases exhausts products such as CO2 and N2. Regeneration of a NOx adsorber can be performed during periods of reduced exhaust gas flow lowering the fuel penalty associated with NOx adsorber regeneration. The pre-cat, NOx adsorber regenerating aftertreatment system of the present invention may be used with any suitable control system.
    Type: Grant
    Filed: February 12, 2004
    Date of Patent: March 8, 2011
    Assignee: Fleetguard, Inc.
    Inventors: Rahul Mital, Bradlee J. Stroia, Shyancherng C. Huang, Robert C. Yu
  • Patent number: 7464688
    Abstract: In an internal combustion engine a fuel-air mixture having compression temperatures and pressures sufficiently low as not to support auto ignition, ignition is achieved by injecting igniting active radicals into the air-fuel mixture. In one embodiment the active radicals are provided by withdrawing a portion of the mixture, treating it to produce active radicals in the portion and returning the portion to the mixture. Treatment of the portion typically includes simultaneously injecting, mixing, and compression of a predetermined amount of pilot fuel within the portion.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: December 16, 2008
    Inventors: Robert C. Yu, Ming-Li Hsu Yu, Robert C. Yu, Jr.
  • Patent number: 7377101
    Abstract: The invention provides a NOx adsorber aftertreatment system for internal combustion engines which utilizes a plasma fuel converter operatively coupled to at least one NOx adsorber to aid in the regeneration of the NOx adsorber. Fuel and engine exhaust is injected into a plasma fuel converter upstream of a NOx absorber producing reductant such as H2, and CO, which are inlet into the NOx absorber. Reductants such as H2 and CO acting along and together help to efficiently regenerate the NOx Adsorber which in turn releases exhausts products such as CO2 and N2. Using the reductants generated by the plasma fuel converter NOx adsorbers, catalytic soot filter, and the like can be regenerated at exhaust temperatures less than 250° C. The plasma fuel converter, NOx adsorber regenerating aftertreatment system of the present invention may be used with any suitable control system.
    Type: Grant
    Filed: February 13, 2004
    Date of Patent: May 27, 2008
    Assignee: Fleetguard, Inc.
    Inventors: Rahul Mital, Bradlee J. Stroia, Robert C. Yu
  • Patent number: 7125633
    Abstract: An imaging member having a charge transport layer with multiple regions or layers is provided. The charge transport layer includes at least two charge transport layers coated from solutions of different components and concentrations, wherein the second (top) transport layer comprises a lower concentration of different charge transport compound than the first (bottom) charge transport layer. The charge transport compound included in the second (top) charge transport layer is a high mobility hole transport compound. The charge transport compound in each layer is dissolved or molecularly dispersed in an electrically inactive film forming polymer to form a solid solution. In such a construction, the resulting dual charge transport layer exhibits enhanced cracking suppression, improves wear resistance, provides excellent imaging member electrical performance, and delivers improved print quality.
    Type: Grant
    Filed: December 12, 2003
    Date of Patent: October 24, 2006
    Assignee: Xerox Corporation
    Inventors: Satchidanand Mishra, Houy Jen Yuh, Anthony M. Horgan, Markus R. Silvestri, Robert C. Yu, Yuh Tong, Dale Renfer, Kenny-tuan Dinh, Geoff Foley, Jack Yanus, Timothy Fuller
  • Patent number: 7033714
    Abstract: An imaging member having a charge transport layer is provided. The charge transport layer includes a plurality of charge transport layers coated from solutions of similar or different compositions or concentrations, wherein the upper or additional transport layer(s) comprise a lower concentration of charge transport compound than the first (bottom) charge transport layer. The charge transport compound included in the first (bottom) charge transport layer may either be the same or different from that included in the additional charge transport layers. The charge transport compound in one or more of the layers is dissolved or molecularly dispersed in an electrically inactive polymer material to form a solid solution. In such a construction, the resulting charge transport layer exhibits enhanced cracking suppression, improves wear resistance, provides excellent imaging member electrical performance, and delivers improved print quality.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: April 25, 2006
    Assignee: Xerox Corporation
    Inventors: Anthony M. Horgan, Robert C Yu, Satchidanand Mishra, Richard L. Post, Edward F. Grabowski, Kathleen M. Carmichael, John R. Lambie
  • Patent number: 7005222
    Abstract: An imaging member having a charge transport layer with multiple regions is provided. The charge transport layer includes a plurality of charge transport layers coated from solutions of similar or different compositions or concentrations, wherein at least the top or uppermost transport layer comprises a lower concentration of charge transport compound than the first (bottom) charge transport layer. The charge transport compound included in the first (bottom) charge transport layer may either be of the same or different compounds from that included in the top or additional charge transport layer(s). The charge transport compound present in each layer may be dissolved or molecularly dispersed in an electrically inactive polymer material to form a solid solution. In such a construction, the resulting charge transport layer exhibits enhanced cracking suppression, improves wear resistance, provides excellent imaging member electrical performance, and delivers improved print quality.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: February 28, 2006
    Assignee: Xerox Corporation
    Inventors: Anthony M. Horgan, Satchidanand Mishra, Robert C. Yu, Richard L. Post, Edward F. Grabowski, Kathleen M. Carmichael, John R. Lambie
  • Patent number: 6922987
    Abstract: The present invention provides for a system and process for enhancing internal combustion engine aftertreatment applications by superheated fuel injection. The system includes a fuel supply upstream of a fuel injector of an aftertreatment application. The system also includes a heater for heating the fuel in the fuel supply. A temperature controller can be used to maintain the heated fuel in a liquid form. When liquid fuel in the pressurized fuel supply is heated, then upon exiting the injector the pressure of the fuel drops rapidly, resulting in atomization of the liquid. The vaporized fuel thereby produced is comprised of extremely small droplets and is elevated in temperature, which reduces the possibility of condensation on internal surfaces of the aftertreatment system. This fine droplet size and resistance to condensation enhances the NOx conversion efficiency of adsorbers. Problems related to premature aging of catalysts and fuel penalties can also be reduced.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: August 2, 2005
    Assignee: Fleetguard, Inc.
    Inventors: Rahul Mital, Scott Cole, Robert C. Yu, Mike Nagel
  • Patent number: 6820414
    Abstract: The present invention provides for adsorber catalysts arranged in parallel. The exhaust flow from the engine is divided in a predetermined ratio between the two catalysts during lean operation (e.g. 50-50). At a predetermined regeneration time (for example, when the adsorber catalyst is 20% full), the exhaust gas flow is reduced through the parallel leg that is to be regenerated (e.g. 20-80). A quantity of hydrocarbon is injected into the reduced-flow leg in order to make the mixture rich. Once the leg has been regenerated, the flow distribution between the parallel legs is reversed, and the other catalyst leg is regenerated while the other side (which is now clean) receives the majority of the exhaust flow. Once both catalyst legs have been regenerated, the exhaust flow is adjusted back to normal (e.g. 50-50) until the catalysts are again ready for regeneration and reduction. A catalytic soot filter is positioned downstream from the adsorber.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: November 23, 2004
    Assignee: Fleetguard, Inc.
    Inventors: Bradlee J. Stroia, Robert C. Yu, Rahul Mital, Michael J. Cunningham
  • Publication number: 20040154287
    Abstract: The present invention provides for a system and process for enhancing internal combustion engine aftertreatment applications by superheated fuel injection. The system includes a fuel supply upstream of a fuel injector of an aftertreatment application. The system also includes a heater for heating the fuel in the fuel supply. A temperature controller can be used to maintain the heated fuel in a liquid form. When liquid fuel in the pressurized fuel supply is heated, then upon exiting the injector the pressure of the fuel drops rapidly, resulting in atomization of the liquid. The vaporized fuel thereby produced is comprised of extremely small droplets and is elevated in temperature, which reduces the possibility of condensation on internal surfaces of the aftertreatment system. This fine droplet size and resistance to condensation enhances the NOx conversion efficiency of adsorbers. Problems related to premature aging of catalysts and fuel penalties can also be reduced.
    Type: Application
    Filed: February 12, 2003
    Publication date: August 12, 2004
    Inventors: Rahul Mital, Scott Cole, Robert C. Yu, Mike Nagel
  • Patent number: 6745560
    Abstract: Exhaust flow from an internal combustion engine is divided in a predetermined ratio between two adsorber catalysts arranged in parallel during lean operation. A regeneration cycle time is predetermined and regeneration is accomplished by injecting hydrocarbons into a catalyst leg having a reduced exhaust flow. Upon regeneration of the catalyst, the exhaust gas flow distribution is reversed and the opposite catalyst is regenerated while the regenerated catalyst bears the brunt of the exhaust flow. The exhaust flow then reverts to a normal (e.g. 50—50) flow distribution until another regeneration cycle is warranted. A catalytic soot filter placed upstream of each adsorber is also regenerated by hydrocarbon injection. The addition of the catalytic soot filter provides more time and surface area for the hydrocarbon to react with the oxygen. Some of the diesel fuel is reformulated into hydrogen and carbon monoxide for superior regeneration.
    Type: Grant
    Filed: July 11, 2002
    Date of Patent: June 8, 2004
    Assignee: Fleetguard, Inc.
    Inventors: Bradlee J. Stroia, Robert C. Yu, Rahul Mital, Michael J. Cunningham
  • Publication number: 20040006975
    Abstract: The present invention provides for adsorber catalysts arranged in parallel. The exhaust flow from the engine is divided in a predetermined ratio between the two catalysts during lean operation (e.g. 50-50). At a predetermined regeneration time (for example, when the adsorber catalyst is 20% full), the exhaust gas flow is reduced through the parallel leg that is to be regenerated (e.g. 20-80). A quantity of hydrocarbon is injected into the reduced-flow leg in order to make the mixture rich. Once the leg has been regenerated, the flow distribution between the parallel legs is reversed, and the other catalyst leg is regenerated while the other side (which is now clean) receives the majority of the exhaust flow. Once both catalyst legs have been regenerated, the exhaust flow is adjusted back to normal (e.g. 50-50) until the catalysts are again ready for regeneration and reduction. A catalytic soot filter is positioned upstream from each adsorber.
    Type: Application
    Filed: July 11, 2002
    Publication date: January 15, 2004
    Inventors: Bradlee J. Stroia, Robert C. Yu, Rahul Mital, Michael J. Cunningham
  • Publication number: 20040006976
    Abstract: The present invention provides for adsorber catalysts arranged in parallel. The exhaust flow from the engine is divided in a predetermined ratio between the two catalysts during lean operation (e.g. 50-50). At a predetermined regeneration time (for example, when the adsorber catalyst is 20% full), the exhaust gas flow is reduced through the parallel leg that is to be regenerated (e.g. 20-80). A quantity of hydrocarbon is injected into the reduced-flow leg in order to make the mixture rich. Once the leg has been regenerated, the flow distribution between the parallel legs is reversed, and the other catalyst leg is regenerated while the other side (which is now clean) receives the majority of the exhaust flow. Once both catalyst legs have been regenerated, the exhaust flow is adjusted back to normal (e.g. 50-50) until the catalysts are again ready for regeneration and reduction. A catalytic soot filter is positioned downstream from the adsorber.
    Type: Application
    Filed: July 11, 2002
    Publication date: January 15, 2004
    Inventors: Bradlee J. Stroia, Robert C. Yu, Rahul Mital, Michael J. Cunningham
  • Patent number: 4962743
    Abstract: A cam for controlling the injection rate of fuel in a fuel injection system having a four part cam profile is disclosed. The first 120.degree. is the plunger advancement segment. The next 80.degree. is the advanced dwell segment. The next 100.degree. is the plunger retraction segment and the last 60.degree. is the retracted dwell segment. The plunger advancement segment is divided into three subsegments: pre-injection stroke, injection stroke, and overtravel stroke. The pre-injection subsegment achieves minimum velocity and acceleration at the start of injection. In the injection subsegment, the cam follower acceleration is achieved as rapidly as can Hertz stress permits to increase the injection pressure and to achieve the maximum injection rate. The overtravel subsegment achieves a sharp and clean end of injection. Preferably, this cam causes injection of less than 20 mm.sup.3 of fuel per stroke during the first ten cam angle degrees of cam rotation.
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: October 16, 1990
    Assignee: Cummins Engine Company, Inc.
    Inventors: Julius P. Perr, Eric Liang, Robert C. Yu, Amarjit S. Ghuman