Patents by Inventor Tutomu Niwa

Tutomu Niwa 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).

  • Aluminum heat exchanger and method for producing aluminum heat exchanger
    Patent number: 4830101
    Abstract: A heat exchanger has special usage such as an evaporator of an automotive air conditioner. This heat exchanger can improve wettability and can reduce a scattering of condensed water. This heat exchanger is treated by a special chemical conversion treatment so that this heat exchanger has two layers of coating on the surface thereof. One of the two layers is a chemical conversion coating formed on the surface of the heat exchanger. The other one is a resin coating formed over the chemical conversion coating. The chemical conversion coating is treated by immersing the heat exchanger into a water solution. The resin coating is also treated by immersing the heat exchanger having the chemical conversion coating into a water solution of organic high polymer material.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: May 16, 1989
    Assignees: Nippondenso Co., Ltd., Nihon Parkerizing Co., Ltd.
    Inventors: Toshio Ohara, Toshio Takahashi, Masayoshi Nishikawa, Tutomu Niwa, Takao Ogino, Ryosuke Sako, Hideaki Kaneko