Patents by Inventor Kazunori Umee

Kazunori Umee 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).

  • Recording head clogging detection method and its device
    Patent number: 6804072
    Abstract: A clogging detector used for a VTR to check the recording state of a recording head without using the reproducing head. A test signal of a lower frequency than the erasing frequency is recorded before and after an information signal by means of an erasing head. Before and after recording the information signal by means of the recording head, the test signal is reproduced, the reproduction output is detected by a detecting circuit, and the level of the output is compared with a preset level by a comparing circuit. When the level is lower than the preset level, a warming is issued from a warming circuit, thus preventing a recording failure due to the clogging of the head.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: October 12, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Yohda, Masaru Higashionji, Haruo Isaka, Hideaki Mukae, Kouhei Baba, Kazunori Umee