Xuesong Zhang, 731613 Greenbrier St, Cape Girardeau, MO 63701

6647611, Nov 18, 2003

Jul 10, 2001

09/901841

Xuesong Zhang - Cape Girardeau MO, 63701

B25B 1100

29559, 269 7

A fixturing or workpiece holding and clamping apparatus or device, as well as method, utilizing the viscosity increase or solidification of a magnetorheological liquid or rigidity increase of a malleable semi-solid or clayish magnetorheological material to secure both regular and irregular shaped workpieces for precision machining or measuring operations. The workpiece is placed in a desired position and orientation in an open cell containing a magnetorheological liquid or medium which conforms to a portion of the surface of the workpiece. A magnet then applies a magnetic field to the magnetorheological liquid or material to increase the viscosity or rigidity thereof, applying a uniform clamping pressure to secure the workpiece in the desired position and orientation for machining or measuring operations. A clamp configured to apply a compressive force to the viscous or rigid magnetorheological medium optionally increases the uniform clamping pressure applied to the workpiece by compressing the magnetorheological material to further increase viscosity and rigidity thereof. The solidified magnetorheological material reverts to a liquid, semi-solid, or clayish state for removal of the fixture and workpiece upon release of the compressive force and removal of the magnetic field.

2003021, Nov 27, 2003

May 23, 2002

10/154017

Xuesong Zhang - Cape Girardeau MO, US

B25B001/22

269/075000

A workpiece coordinate positioning system and method for use with a workpiece holding apparatus comprising a workpiece tracking system and a workpiece positioning system between which a workpiece is secured. Movement of the workpiece during clamping or machining operations is observed through the workpiece tracking system. The workpiece positioning system is configured with a drive mechanism utilized to compensate for the observed movements, maintaining the workpiece in a predetermined positions and orientation.

6267364, Jul 31, 2001

Feb 18, 2000

9/506890

Xuesong Zhang - Cape Girardeau MO

B25B 1100

269 7

A fixturing or workpiece holding and clamping apparatus or device, as well as method, utilizing the viscosity increase or solidification of a magnetorheological fluid work contacting medium to secure both regular and irregular shaped workpieces for precision machining or measuring operations. The apparatus or device comprises a perforated fixture into which the workpiece is placed in a desired position and orientation. The perforated fixture and positioned workpiece are placed in an open cell containing a magnetorheological fluid which conforms to a portion of the surface of the workpiece. A magnet then applies a magnetic field to the magnetorheological fluid to increase the viscosity thereof and to solidify the fluid around the workpiece with a uniform clamping pressure, securing the workpiece in the desired position and orientation for machining or measuring operations. A clamp configured to apply a compressive force to the solidified magnetorheological fluid optionally increases the uniform clamping pressure applied to the workpiece by compressing the solidified magnetorheological fluid to further increase viscosity and solidification thereof. The solidified magnetorheological fluid attenuates vibrations in the workpiece, and reverts to a liquid state for removal of the perforated fixture and workpiece upon removal of the compressive force and the magnetic field.

6182954, Feb 6, 2001

Jul 19, 1999

9/356342

Xuesong Zhang - Cape Girardeau MO

B25B 1100

269 7

A work piece holding apparatus uses a magnetorheological fluid for holding a work piece firmly for machining process and/or measurements. The apparatus includes a cell with a hollow space in it and magnetorheological fluid is put into the hollow space. A special fixture with a hollow space in it is used to hold a work piece by screws in the wall or walls. The fixture with a work piece in it is fastened inside the cell dipped in magnetorheological fluid to absorb the extra force beyond the holding power supplied by magnetorheological fluid alone. It then overcomes any climbing that may happen during any process. A magnetic field is supplied to the cell to make the magnetorheological fluid work. It is well known that if a magnetic field is applied to a magnetorheological fluid, the viscosity of the fluid will be increased tremendously and behaves almost like a solid. A pressure applied in this apparatus to the magnetorheological fluid while the magnetic field is "on" will increase the viscosity of a magnetorheological fluid many times.