Patents by Inventor David S. Yang
David S. Yang 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: 10751830Abstract: A welding electrode is disclosed that includes an electrode welding shell and a blind adapter that are joined together to cooperatively define an internal cavity. The electrode welding shell and the blind adapter may be integrally formed or they may be distinct components that are attached together. The presence of the internal cavity defined by the electrode welding shell and the blind adapter reduces the thermal mass of the welding electrode and slows the rate of conductive heat transfer from the weld face to a cooling fluid, which allows in the center of the weld face to retain heat for a longer duration once current flow through the welding electrode is terminated, thereby positively affecting the spot welding process for particular types of workpiece stack-ups including those that include an aluminum workpiece and an overlapping adjacent steel workpiece.Type: GrantFiled: April 8, 2017Date of Patent: August 25, 2020Assignee: GM Global Technology Operations LLCInventors: David R. Sigler, David S. Yang
-
Patent number: 10688595Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping steel workpieces (12, 14) comprises directing a laser beam (40) at a top surface (26) of the workpiece stack-up to form a keyhole (56) surrounded by a molten steel weld pool (58). The laser beam is conveyed along a predefined weld pattern that includes one or more nonlinear inner weld paths (66) and an enclosed outer peripheral weld path (68) surrounding the one or more nonlinear inner weld paths. During conveyance of the laser beam along the one or more nonlinear inner weld paths, the keyhole fully penetrates through the workpiece stack-up from the top surface of the stack-up to the bottom surface (28) of the stack-up. The method produces weld joints between the steel workpieces that do not have an intentionally imposed gap formed between their faying surfaces.Type: GrantFiled: June 2, 2015Date of Patent: June 23, 2020Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: David S. Yang, Justin Allen Wolsker, Jing Zhang, Wu Tao, Dalong Gao
-
Patent number: 10682723Abstract: A method of resistance spot welding a steel workpiece and an aluminum or aluminum alloy workpiece, and a welding electrode used therein. In one step of the method a workpiece stack-up is provided. The workpiece stack-up includes a steel workpiece and an aluminum or aluminum alloy workpiece. Another step of the method involves contacting the aluminum or aluminum alloy workpiece with a weld face of the welding electrode. The welding electrode has a body and an insert. The insert is composed of a material having an electrical resistivity that is greater than an electrical resistivity of the material of the body. The weld face has a first section defined by a surface of the insert and has a second section defined by a surface of the body. Both the first and second sections make surface-to-surface contact with the aluminum or aluminum alloy workpiece amid resistance spot welding.Type: GrantFiled: April 13, 2016Date of Patent: June 16, 2020Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: David R. Sigler, Blair E. Carlson, James G. Schroth, David S. Yang, Anil K. Sachdev
-
Patent number: 10569477Abstract: A method of attaching a thermoplastic-based workpiece and a metal workpiece involves the use of a metal reaction coating. The metal reaction coating is applied over a base metal substrate of the metal workpiece such that the metal reaction coating faces and contacts the thermoplastic-based workpiece when the two workpieces are assembled in overlapping fashion. To attach the workpieces at their faying interface, an energy source such as, for example, a laser beam or an electric arc, is directed against the metal workpiece to create a zone of concentrated heat that at least warms up the metal reaction coating and melts a portion of the thermoplastic-based workpiece. Such heated activity at the faying interface promotes interfacial chemical bonding between the thermoplastic-based workpiece and the metal workpiece that contributes to an enhanced attachment between the workpieces.Type: GrantFiled: January 26, 2015Date of Patent: February 25, 2020Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: Jing Zhang, David S. Yang, Shawn Deng
-
Patent number: 10421148Abstract: A method of resistance spot welding a workpiece stack-up that includes an aluminum workpiece and an adjacent overlapping steel workpiece is disclosed. The method uses a first welding electrode positioned proximate the aluminum workpiece and a second welding electrode positioned proximate the steel workpiece to effectuate the spot welding process. In an effort to positively affect the strength of the ultimately-formed weld joint, external heat may be supplied to the first welding electrode by an external heating source disposed in heat transfer relation with the first welding electrode either before or after, or both before or after, an electrical current is passed between the first and second welding electrodes to create a molten aluminum weld pool within the aluminum workpiece.Type: GrantFiled: April 25, 2016Date of Patent: September 24, 2019Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: David R. Sigler, David S. Yang, Anil K. Sachdev
-
Publication number: 20180304405Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping aluminum workpieces (12, 14) comprises advancing a laser beam (24) relative to a plane of a top surface (20) of the workpiece stack-up (10) and along a spot weld travel pattern (74) that includes one or more nonlinear inner weld paths and an outer peripheral weld path that surrounds the one or more nonlinear inner weld paths. Such advancement of the laser beam (24) along the spot weld travel pattern (74) translates a keyhole (78) and a surrounding molten aluminum weld pool (76) along a corresponding route relative to the top surface (20) of the workpiece stack-up (10). Advancing the laser beam (24) along the spot weld travel pattern (74) forms a weld joint (72), which includes resolidified composite aluminum workpiece material derived from each of the aluminum workpieces (12, 14) penetrated by the surrounding molten aluminum weld pool (76), that fusion welds the aluminum workpieces (12, 14) together.Type: ApplicationFiled: November 6, 2015Publication date: October 25, 2018Inventors: David S. Yang, Jing Zhang, Wu Tao, Justin A. Wolsker
-
Publication number: 20180214983Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping aluminum workpieces (12, 14), at least one of which includes a protective anti-corrosion coating (38), is disclosed. The disclosed method includes advancing the laser beam (56) relative to the top surface (26) of the workpiece stack-up (10) along a travel path (78, 78?, 78?, 78??) that imposes bidirectional movement of the laser beam (56). In particular, the laser beam (56) moves in a forward direction (80) while also moving back and forth in a lateral direction (82) oriented transverse to the forward direction (80) as it is being advanced relative to the top surface (26). Such bidirectional movement is believed to help disturb the protective anti-corrosion coating (38) in and around the molten aluminum weld pool (74), thus leading to a laser weld joint (68) that contains less weld defects derivable from the protective anti-corrosion coating(s) (38).Type: ApplicationFiled: August 31, 2015Publication date: August 2, 2018Inventors: David S. Yang, Wu Tao
-
Patent number: 10010966Abstract: A method of spot welding a workpiece stack-up that includes a steel workpiece and an aluminum alloy workpiece involves passing an electrical current through the workpieces and between welding electrodes that are constructed to affect the current density of the electrical current. The welding electrodes, more specifically, are constructed to render the density of the electrical current greater in the steel workpiece than in the aluminum alloy workpiece. This difference in current densities can be accomplished by passing, at least initially, the electrical current between a weld face of the welding electrode in contact with the steel workpiece and a perimeter region of a weld face of the welding electrode in contact with the aluminum alloy workpiece.Type: GrantFiled: February 14, 2014Date of Patent: July 3, 2018Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: David S. Yang, David R. Sigler, Blair E. Carlson, James G. Schroth, Michael J. Karagoulis
-
Publication number: 20180141158Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping steel workpieces (12, 14) comprises directing a laser beam (40) at a top surface (26) of the workpiece stack-up to form a keyhole (56) surrounded by a molten steel weld pool (58). The laser beam is conveyed along a predefined weld pattern that includes one or more nonlinear inner weld paths (66) and an enclosed outer peripheral weld path (68) surrounding the one or more nonlinear inner weld paths. During conveyance of the laser beam along the one or more nonlinear inner weld paths, the keyhole fully penetrates through the workpiece stack-up from the top surface of the stack-up to the bottom surface (28) of the stack-up. The method produces weld joints between the steel workpieces that do not have an intentionally imposed gap formed between their faying surfaces.Type: ApplicationFiled: June 2, 2015Publication date: May 24, 2018Inventors: David S. Yang, Justin Allen Wolsker, Jing Zhang, Wu Tao, Dalong Gao
-
Publication number: 20180022038Abstract: A method of attaching a thermoplastic-based workpiece and a metal workpiece involves the use of a metal reaction coating. The metal reaction coating is applied over a base metal substrate of the metal workpiece such that the metal reaction coating faces and contacts the thermoplastic-based workpiece when the two workpieces are assembled in overlapping fashion. To attach the workpieces at their faying interface, an energy source such as, for example, a laser beam or an electric arc, is directed against the metal workpiece to create a zone of concentrated heat that at least warms up the metal reaction coating and melts a portion of the thermoplastic-based workpiece. Such heated activity at the faying interface promotes interfacial chemical bonding between the thermoplastic-based workpiece and the metal workpiece that contributes to an enhanced attachment between the workpieces.Type: ApplicationFiled: January 26, 2015Publication date: January 25, 2018Inventors: Jing Zhang, David S. Yang, Shawn Deng
-
Publication number: 20170304925Abstract: A method of resistance spot welding a workpiece stack-up that includes an aluminum workpiece and an adjacent overlapping steel workpiece is disclosed. The method uses a first welding electrode positioned proximate the aluminum workpiece and a second welding electrode positioned proximate the steel workpiece to effectuate the spot welding process. In an effort to positively affect the strength of the ultimately-formed weld joint, external heat may be supplied to the first welding electrode by an external heating source disposed in heat transfer relation with the first welding electrode either before or after, or both before or after, an electrical current is passed between the first and second welding electrodes to create a molten aluminum weld pool within the aluminum workpiece.Type: ApplicationFiled: April 25, 2016Publication date: October 26, 2017Inventors: David R. Sigler, David S. Yang, Anil K. Sachdev
-
Publication number: 20170297135Abstract: A method of resistance spot welding a steel workpiece and an aluminum or aluminum alloy workpiece, and a welding electrode used therein. In one step of the method a workpiece stack-up is provided. The workpiece stack-up includes a steel workpiece and an aluminum or aluminum alloy workpiece. Another step of the method involves contacting the aluminum or aluminum alloy workpiece with a weld face of the welding electrode. The welding electrode has a body and an insert. The insert is composed of a material having an electrical resistivity that is greater than an electrical resistivity of the material of the body. The weld face has a first section defined by a surface of the insert and has a second section defined by a surface of the body. Both the first and second sections make surface-to-surface contact with the aluminum or aluminum alloy workpiece amid resistance spot welding.Type: ApplicationFiled: April 13, 2016Publication date: October 19, 2017Inventors: David R. Sigler, Blair E. Carlson, James G. Schroth, David S. Yang, Anil K. Sachdev
-
Publication number: 20170291248Abstract: A welding electrode is disclosed that includes an electrode welding shell and a blind adapter that are joined together to cooperatively define an internal cavity. The electrode welding shell and the blind adapter may be integrally formed or they may be distinct components that are attached together. The presence of the internal cavity defined by the electrode welding shell and the blind adapter reduces the thermal mass of the welding electrode and slows the rate of conductive heat transfer from the weld face to a cooling fluid, which allows in the center of the weld face to retain heat for a longer duration once current flow through the welding electrode is terminated, thereby positively affecting the spot welding process for particular types of workpiece stack-ups including those that include an aluminum workpiece and an overlapping adjacent steel workpiece.Type: ApplicationFiled: April 8, 2017Publication date: October 12, 2017Inventors: David R. Sigler, David S. Yang
-
Publication number: 20170239750Abstract: A method of laser welding a workpiece stack-up includes directing a laser beam at a top surface of a first metal workpiece to form a key-hole that entirely penetrates the workpiece stack-up, including an underlying second metal workpiece, so that the keyhole reaches a bottom surface of the second metal workpiece. A zone of negative pressure established under the bottom surface of the second metal workpiece extracts vapors that are produced by the laser beam. The vapors, in particular, are extracted from the bottom surface of the second metal workpiece through the keyhole. A bottom workpiece holder that supports the bottom metal workpiece during laser welding may be constructed to establish the zone of negative pressure.Type: ApplicationFiled: August 25, 2014Publication date: August 24, 2017Inventors: David S. Yang, Justin A. Wolsker, Bradley J. Blaski, Jeff Wang, Jing Zhang, Wu Tao
-
Publication number: 20170157697Abstract: A welding electrode suitable for resistance spot welding applications includes a first portion, a second portion, and a reduced diameter portion that extends between and connects the first and second portions. The first portion includes a weld face and the second portion includes a mounting base that opens to an internal recess having a cooling pocket. The reduced diameter portion extends between a back surface of the first portion and a front surface of the second portion such that a gap separates the back and front surfaces from each other. The gap may be vacant or filled with a low conductivity material. The disclosed welding electrode may be used in conjunction with another welding electrode to resistance spot weld a workpiece stack-up that includes an aluminum workpiece and an adjacent overlapping steel workpiece.Type: ApplicationFiled: December 8, 2015Publication date: June 8, 2017Inventors: David S. Yang, David R. Sigler
-
Patent number: 9333588Abstract: Methods of crack avoidance during resistance spot welding are provided. The compressive stress from the spot welding is distributed across an electrode assembly having an enlarged footprint. The electrode assembly includes a conductive core and a non-conductive cover. The delivery of current through the electrode assembly is localized to the conductive core.Type: GrantFiled: January 28, 2011Date of Patent: May 10, 2016Assignee: GM Global Technology Operations LLCInventors: Blair E. Carlson, Pei-Chung Wang, David S. Yang
-
Publication number: 20150231729Abstract: A method of spot welding a workpiece stack-up that includes a steel workpiece and an aluminum alloy workpiece involves passing an electrical current through the workpieces and between welding electrodes that are constructed to affect the current density of the electrical current. The welding electrodes, more specifically, are constructed to render the density of the electrical current greater in the steel workpiece than in the aluminum alloy workpiece. This difference in current densities can be accomplished by passing, at least initially, the electrical current between a weld face of the welding electrode in contact with the steel workpiece and a perimeter region of a weld face of the welding electrode in contact with the aluminum alloy workpiece.Type: ApplicationFiled: February 14, 2014Publication date: August 20, 2015Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: David S. Yang, David R. Sigler, Blair E. Carlson, James G. Schroth, Michael J. Karagoulis
-
Publication number: 20120193331Abstract: Methods of crack avoidance during resistance spot welding are provided. The compressive stress from the spot welding is distributed across an electrode assembly having an enlarged footprint. The electrode assembly includes a conductive core and a non-conductive cover. The delivery of current through the electrode assembly is localized to the conductive core.Type: ApplicationFiled: January 28, 2011Publication date: August 2, 2012Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLCInventors: Blair E. Carlson, Pei-Chung Wang, David S. Yang
-
Patent number: 5417522Abstract: An apparatus for constructing subterranean structures, soil-chemicals mixture or soil-agents mixture by using a multi-shaft auger machine to mix soil with a chemical hardener in situ in a borehole. As the auger shafts of the multi-shaft auger machine penetrate the soil, a plurality of lateral support structures shear soil and provide additional lateral support. The plurality of lateral support structures are spaced vertically by a length no greater than thirty feet. Additionally, soil fragmentation members attached to the lateral support structures fragment soil reconsolidations to aid in mixing of soil. The soil fragmentation members have a length no greater than the difference between the radius of at least one auger blade and the radius of the shaft and no less than one-third the difference between the radius of at least one auger blade and the radius of the shaft.Type: GrantFiled: September 23, 1993Date of Patent: May 23, 1995Assignee: S. M. W. SeikoInventors: Ikuo Kono, David S. Yang
-
Patent number: 5378085Abstract: Methods are provided for the constructing of subterranean soil-cement structures in situ. The methods utilize techniques designed to prolong the period of time in which an auger machine can operate in a bore hole without encountering difficulty due to the hardening of the soil-cement mixture. The techniques utilized include a preparatory drilling phase during which a lubricating slurry may be injected. This preparatory drilling serves to break up the soil and particularly if a lubricating slurry is used, reduce friction so that final drilling may progress more quickly. After preparatory drilling, final drilling takes place. Final drilling is divided into a downward and an upward phase. Either hardening or non-hardening slurry may be introduced and consolidated with the soil during the downward phase, but only hardening slurry is typically utilized during the upward phase of final drilling.Type: GrantFiled: October 1, 1993Date of Patent: January 3, 1995Assignee: S. M. W. SeikoInventors: Ikuo Kono, David S. Yang