Patents by Inventor Alan J. Harris

Alan J. Harris 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: 4966077
    Abstract: A positive displacement explosive base dosing pump is provided with a drive motor 14 and has an outlet 22 connected via a flexible hose 24 to a lance 70. The lance 70 has a mixing device 72 therein and a reciprocable positive displacement gassing solution dosing pump has an outlet connected via a flexible conduit 54 to the lance and feeding into the lance upstream of the mixing device 72. The invention involves using the base dosing pump 12 to pump explosive base from a supply 78 along the hose 24 to the lance 70 while the gassing solution dosing pump 16 simultaneously pumps gassing solution from a supply 56 along the flexible conduit 54. The conduit 54 leads the solution into the lance 70 upstream of the mixing device 72 whereby the explosive base is mixed with the solution, so that a mixture issues from the lance 70 which become sensitized after reaction has taken place between the base and solution.
    Type: Grant
    Filed: April 20, 1989
    Date of Patent: October 30, 1990
    Assignee: AECI Limited
    Inventors: Pieter S. Halliday, Gareth Tucker, Carl H. Lubbe, Alan J. Harris, David G. Russell
  • Patent number: 4631883
    Abstract: A tendon for post-tensioned pre-stressed concrete structures in which between the strand and sheath there is provided, in quiescent condition, a latent hardenable material and an activator therefor so that when the strand is tensioned the activator is activated to commence the hardening process of the hardenable material and produce a bonded tendon.
    Type: Grant
    Filed: May 17, 1984
    Date of Patent: December 30, 1986
    Assignee: PSC Freyssinet Limited
    Inventors: Alan J. Harris, Gordon E. R. Wright