Patents by Inventor M. J. Hsu

M. J. Hsu 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).

  • Laser cutting of eggshells
    Patent number: 5285750
    Abstract: Preparation of chicken embryo allantoic fluids for animal health requires opening the eggshell by cutting, drilling or punching methods. Laser cutting and drilling is used as an alternative to known processes. Both CO.sub.2 and Nd:YAG lasers are employed. A focused CO.sub.2 laser beam at a power of 200 watts in conjunction with an X-Y motion table produced 25 mm diameter "clean-cuts" in eggshells with a cutting time of 0.5 seconds per egg. The material removal mechanism was vaporization. When an axicon/lens combination is used with a CO.sub.2 laser, the cutting time was further reduced to 0.2 seconds per egg and the mechanism of material removal is changed from vaporization to decomposition of the eggshell into fine powders. Small holes, typical diameters of 0.5 mm to 1 mm are generated in the eggshell using the pulsed Nd:YAG laser.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: February 15, 1994
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: P. A. Molian, Jerry L. Hall, M. J. Hsu