Patents by Inventor David W. Louwenaar

David W. Louwenaar 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).

  • Solar warming hut
    Patent number: 4497145
    Abstract: A small portable enclosure has at least one windowlike surface for admitting the rays of the sun and an opaque interior to absorb the energy of those admitted sun rays, thereby raising the hut's interior temperature and consequently warming the hut's occupants. At least one safety vent is provided to control the hut's interior temperature and pressure.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: February 5, 1985
    Inventor: David W. Louwenaar
  • Solar shield
    Patent number: 4287683
    Abstract: A solar shield for room windows reflects and dissipates solar energy by means of a reflective surface and backing piece between which is defined a warm air channel. The backing piece is positioned away from the window surface so that sunlight is admitted between the backing piece and the window being shielded.
    Type: Grant
    Filed: January 21, 1980
    Date of Patent: September 8, 1981
    Inventor: David W. Louwenaar