Jian Wen Cao

US Patent:

6769280, Aug 3, 2004

Filed:

May 7, 2002

Appl. No.:

10/140916

Inventors:

Jian Cao - Wilmette IL
Junghoon Lee - Wilmette IL
Michael Peshkin - Evanston IL

Assignee:

Northwestern University - Evanston IL

International Classification:

B21D 2222

US Classification:

72 173, 72347, 72350

Abstract:

A method and system for providing real time measurements of draw-in for closed loop control of a metal forming process including an elongated sensor on one of the tools positioned in the proximity of the deformation zone and adjacent to an edge of a sheet metal blank being formed. The sensor includes coils disposed in a signal coupling relationship and during the forming process, a signal applied to one of the coils induces a signal in the coil, producing a response signal that varies linearly as a function of the amount of overlap between the sensor and the sheet metal blank as the sheet metal blank is drawn into the deformation zone. A feedback signal produced from the response signal is used to control a parameter of the forming process as a function of retreat of the edge of the sheet metal blank into the deformation zone.

US Patent:

8408039, Apr 2, 2013

Filed:

Oct 6, 2009

Appl. No.:

12/587408

Inventors:

Jian Cao - Wilmette IL, US
Anthony Swanson - Chicago IL, US
Tiffany Davis - Chicago IL, US

Assignee:

Northwestern University - Evanston IL

International Classification:

B21J 11/00
B21D 5/06
B21B 27/06

US Classification:

72418, 72446, 72455, 723792, 72404, 72414, 72462

Abstract:

Method of forming depressions (e. g. dimples) in a sheet material to form a textured surface thereon involves pressing one or more tool tips into a metallic or non-metallic sheet material while the sheet material is supported by a support layer that is relatively softer (e. g. having a lower Young's modulus) than the sheet material so as to allow plastic deformation and reduce pile-up of raised displaced material of the sheet material at the edges of the depressions.

US Patent:

20110084648, Apr 14, 2011

Filed:

Oct 9, 2009

Appl. No.:

12/576803

Inventors:

Jian Cao - Chicago IL, US
Ali Emadi - Chicago IL, US

International Classification:

H02J 7/00

US Classification:

320103, 320167, 307 91

Abstract:

A hybrid energy storage system for supplying power to an application with a fluctuating load profile, such as, for example, electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, wind energy harvesting equipment and solar energy harvesting equipment. The hybrid energy storage system includes an ultra-capacitor electrically connected to a DC bus and a power source electrically connected to the DC bus via a controlled switch. The hybrid energy storage system further including a DC/DC converter connected between the power source and the ultra-capacitor, the DC/DC converter boosting a voltage of the power source to charge the ultra-capacitor. The DC/DC converter is preferably controlled to maintain a voltage of the ultra-capacitor at a higher value than the voltage of the power source.

US Patent:

20120164384, Jun 28, 2012

Filed:

Dec 15, 2011

Appl. No.:

13/374210

Inventors:

Jian Cao - Wilmette IL, US
Rui Zhou - Evanston IL, US
Kornel F. Ehmann - Evanston IL, US

International Classification:

B32B 3/00
B29C 59/02

US Classification:

428141, 425385, 264293

Abstract:

A compact deformation-based micro-texturing apparatus and method employ flexure bearing houses for rotatably supporting opposite ends of each of a first (e.g. upper) roll and a second (e.g. lower) roll to provide a working roll gap between the rolls, wherein at least one of the rolls has one or more micro surface features to plastically deform a surface of a workpiece deformed by rolling action in the roll gap. An electrical current may be passed through the workpiece to assist micro deformation. A roll gap adjusting device is operably associated with the first and second flexure bearing houses for adjusting the roll gap dimension to the final depth of the micro surface features to be imparted to the surface of the workpiece by the rolling action.

US Patent:

59411104, Aug 24, 1999

Filed:

May 12, 1997

Appl. No.:

8/854480

Inventors:

Jian Cao - Wilmette IL
Brad L. Kinsey - Clio MI

Assignee:

Northern University - Evanston IL

International Classification:

B21B 3700

US Classification:

72 214

Abstract:

Method and apparatus for TWB forming with adaptive control of movable punch and/or die segments in a manner to maintain a holding force at the weld line by the punch and die segments during at least initial forming of the blank in a manner to control and limit movement of the weld line. A tailor welded metal blank having a weld line is positioned between a punch and a die with the weld line spanning a cavity defined between the punch and the die. One or more individual segments of the punch and of the die are moved in a manner to engage opposite side regions of the weld line to apply a holding force to the weld line. Relative movement of the punch and/or die segments is adaptively controlled during at least initial deformation of the blank by the punch in a manner to maintain the holding force applied to weld line at a selected holding force value to retain the weld line in a plane defined by the punch and die segments, thereby reducing weld line movement. After initial deformation of the blank by movement of the punch to a preset punch location, the punch and die segments can be retracted away from the weld line during subsequent deformation of the blank.

US Patent:

20210260848, Aug 26, 2021

Filed:

May 23, 2019

Appl. No.:

17/057805

Inventors:

- Evanston IL, US
Nicolas Martinez Prieto - Evanston IL, US
Jian Cao - Wilmette IL, US
Kyoo-Chul Park - Wilmette IL, US
Christian John Machado - Evanston IL, US

International Classification:

B32B 5/02
B32B 15/20
B32B 15/14
B32B 38/08

Abstract:

Self-healing, hydrophobic composites and related methods are provided. A method of repelling water may comprise forming a layer of a self-healing, hydrophobic composite comprising a porous network of entangled polymer fibers and a hydrophobic phase change material infused throughout the network, on a surface of a substrate to form a treated surface; and exposing the treated surface to water, wherein the treated surface exhibits a native water droplet contact angle which is greater than that of an untreated surface without the layer of the composite.

US Patent:

20200188974, Jun 18, 2020

Filed:

Oct 6, 2017

Appl. No.:

16/341163

Inventors:

- Evanston IL, US
Kornel Ehmann - Evanston IL, US
Man Kwan Ng - Evanston IL, US
Jian Cao - Wilmette IL, US

Assignee:

Northwestern University - Evanston IL

International Classification:

B21B 37/46
B21B 19/06
B21B 1/20
B21B 39/02
B21B 35/06

Abstract:

A rolling mill system for Incremental rotary shaping of an elongated workpiece is provided that includes first and second workpiece holders. A support frame has a track with the first and second workpiece holders being movably associated with the track, the workpiece holders and an associated workpiece being movable in unison along the track. A radial chuck is mounted to the frame that includes a plurality of jaws that are movable radially inwardly and outwardly. Each jaw has a tool mounted thereto that is rotatable about an axis of rotation, with the axis of rotation of each tool being oriented at a skew angle relative to the longitudinal axis of a workpiece. A source of electric current and an electrically conductive flow path are provided for flowing electrical current through a workpiece. A controller is provided that is configured to control the operation of each of the first motor, second motor and third motor, and to control the flow of current flowing through the tools to the workpiece.

US Patent:

20190184494, Jun 20, 2019

Filed:

Dec 18, 2018

Appl. No.:

16/223534

Inventors:

- Evanston IL, US
Kornel Ehmann - Evanston IL, US
Jian Cao - Wilmette IL, US

International Classification:

B23K 26/342
B33Y 30/00
B33Y 50/02
B33Y 10/00
B23K 26/03
B23K 15/00
B23K 26/082
B23K 26/70
B23K 26/146
B23K 26/14

Abstract:

A system for making a build using directed energy deposition is provided. The system includes a primary heat source; a processing nozzle movable relative to the build for delivering a metal powder, a carrier gas for the metal powder, and a shield gas to the build; a melt pool sensor for providing information regarding a temperature of a melt pool of the build; a secondary heat source separate from the primary heat source positionable relative to the build for delivering heat to a selected area of the build; a cooling source positionable relative to the build for delivering a cooling fluid to a selected area of the build; and a control system for operating the primary heat source, the secondary heat source and the cooling source to maintain a desired temperature profile for the build. The system preferably includes a temperature sensor for providing a temperature profile of the build. The temperature control system preferably includes a programmable controller configured to control the secondary heat source and the cooling source to conform the temperature of the build to the desired temperature profile. In one embodiment, the programmable controller is pre-programmed with a dynamic thermal model of a thermal history of the build for each time step.