Patents by Inventor Forrest Xu

Forrest Xu 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).

  • Publication number: 20120197586
    Abstract: An I/O circuit for measuring temperatures within an industrial control system uses a stored empirical model together with input from at least one reference temperature sensor to determine inter-terminal temperature differences for more accurate cold junction compensation.
    Type: Application
    Filed: February 1, 2012
    Publication date: August 2, 2012
    Inventors: Rain Jilin Zhang, Ting Wu, Forrest Xu Caigang
  • Patent number: 7685854
    Abstract: An axial spring balancing pin tumbler lock includes a cylindrical shell, a plug rotationally disposed within the shell and rotatable by a tubular key. The shell contains a plurality of first pin bores annularly and evenly defined to the axis of the shell for receiving first pins and first springs. The plug has a through aperture for engaging with a elongated spindle, a key bore coaxially defined on front end for receiving the tubular key, a plurality of third pin bores annularly and evenly defined on front end with same depth of the key bore for receiving third pins, and a plurality of second pin bores defined on rear end of the plug for receiving second pins and second springs. Each second pin may contacts the tubular key and one of third pins simultaneously.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: March 30, 2010
    Inventors: Forrest Xu, Daniel Xu
  • Publication number: 20100024499
    Abstract: A high security cylinder lock includes a housing comprising a plurality of driver pin bores for disposing spring loaded driver pins; a plug rotatable within the housing comprising a plurality of balancing pin bores for disposing spring loaded balancing pins and a plurality of combination pin bores for disposing combination pins. Each combination pin is sandwiched between a driver pin and a balancing pin. The extension force of the balancing spring at its pre-load length is greater than the extension force of the driver spring at its fully-load length. The compound force causes at least one combination pin partially extended into a corresponding driver pin bore in the housing when the plug is at its first rotational orientation in case of no key engaged. The key profile pushes the balancing pins to move to such position that all mating surfaces of the combination pins and the driver pins to lies onto the shear line of the lock.
    Type: Application
    Filed: July 31, 2009
    Publication date: February 4, 2010
    Inventors: Forrest Xu, Daniel Xu
  • Publication number: 20090188287
    Abstract: An axial pin tumbler lock including a shell comprising a plurality of chambers formed in a radial pattern around a circle; a rotatable plug containing a through hole for mounting a center post, a main bore for receiving a tubular key, a first plurality of chambers formed in a radial pattern around a circle on its front end and arranged in such a way that each one of the first chambers in the plug extends coaxially with a corresponding chamber on said shell, and a second plurality of chambers formed in a radial pattern around a relatively smaller circle on its rear end, disposed in the shell; a plurality of spring-loaded driver pins disposed in the chambers on said shell; a plurality of spring loaded balance pins disposed in the second chambers and a plurality of combination pins disposed in the first chambers of said plug and initially extended into the chambers on said shell under compound extension force of the balance springs and the driver springs when the plug is at its locking position.
    Type: Application
    Filed: January 30, 2008
    Publication date: July 30, 2009
    Inventors: Forrest Xu, Daniel Xu