Patents by Inventor Yoshitaro Ishii

Yoshitaro Ishii 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: 4912593
    Abstract: An electrical appliance utilizes felt for causing a corona discharge to allow accumulated static electricity to be discharged, and a conductive member having a grounding effect and constituted by a pressure washer or the like is provided in the vicinity of the felt, at a distance of 4 mm or greater therefrom. The felt is made of acrylonitrile-copper sulfate composite fibers.
    Type: Grant
    Filed: June 1, 1988
    Date of Patent: March 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Akira Iwao, Yasuyuki Hiruta, Yoshitaro Ishii
  • Patent number: 4905341
    Abstract: Disclosed is an upright-type electric vacuum cleaner which comprises a suction port body provided with a rotary brush and a main body case supported tiltably on the suction port body. Improvements are made in details such as the arrangement for supporting the main body case in the suction port body, the arrangements of mounting a handle onto the main body case, the configuration of a main body duct, the arrangement of a rotary brush, the arrangement of a cover of the main body case, and the arrangement of a T-shaped joint for connecting the main body duct and a dust filter means, thereby increasing the strength and rigidity of each of these parts and improving the performance of the vacuum cleaner.
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: March 6, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Masao Sunagawa, Kazuhiro Kubota, Yoshitaro Ishii, Susumu Satoh
  • Patent number: 4893376
    Abstract: Disclosed is an upright-type electric vacuum cleaner which comprises a suction port body provided with a rotary brush and a main body case supported tiltably on the suction port body. Improvements are made in details such as the arrangement for supporting the main body case in the suction port body, the arrangements of mounting a handle onto the main body case, the configuration of a main body duct, the arrangement of a rotary brush, the arrangement of a cover of the main body case, and the arrangement of a T-shaped joint for connecting the main body duct and a dust filter means, thereby increasing the strength and rigidity of each of these parts and improving the performance of the vacuum cleaner.
    Type: Grant
    Filed: December 21, 1988
    Date of Patent: January 16, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Masao Sunagawa, Kazuhiro Kubota, Yoshitaro Ishii, Susumu Satoh
  • Patent number: 4880474
    Abstract: Method and apparatus for operating a vacuum cleaner in which by detecting a rotational speed of a variable speed fan motor adapted to give a suction force to the cleaner and its change range, the choking state of the filter and the state of the cleaned surface are discriminated, and a speed command of the fan motor is corrected on the basis of the result of the discrimination, and the comfortable cleaning can be performed by the optimum suction force.
    Type: Grant
    Filed: October 8, 1987
    Date of Patent: November 14, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Haruo Koharagi, Kazuo Tahara, Tsunehiro Endo, Kunio Miyashita, Yoshitaro Ishii, Fumio Jyoraku, Syuji Watanabe, Hisanori Toyoshima, Kohichi Saito, Wakichiro Hishi, Koujirou Yamashita
  • Patent number: 4809394
    Abstract: A vacuum cleaner with panel portion structure which includes an improved panel main body and a blower facility valve body. The panel main body has an exhaust air port and an opening for a blower facility. The blower facility valve body is provided at a lower side of the panel main body and is rotatably supported so as to normally shut the blower facility opening. A first exhaust air passage is formed between the intermediate exhaust air port to the main body exhaust air port. A second exhaust air passage is formed between the intermediate exhaust air port to the blower facility opening. The first exhaust air passage and the second exhaust air passage are changed over by the blower facility valve body. The improved blower facility structure permits the development of a series of vacuum cleaners with and without a blower facility.
    Type: Grant
    Filed: August 31, 1987
    Date of Patent: March 7, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Hisao Suka, Akira Iwao, Kazuhiro Kubota, Yoshitaro Ishii, Masao Sunagawa
  • Patent number: 4446594
    Abstract: An upright type electric cleaner including a main body case (1) and a suction port body (1), wherein when the main body case is brought to an upright position as the machine is inoperative, a rotary brush extending downwardly from the bottom of the suction port body (1) is released from contact with the surface to be cleaned. The suction port body includes a single switching knob which, when manipulated, enables the speed of operation of the rotary brush and the distance between the rotary brush and the surface to be cleaned to be adjusted simultaneously. A part of exhaust air of the cleaner released through a blower is led through a sound absorbing duct located in a bag compartment into a cord reel chamber to thereby greatly reduce the noise level of exhaust and preventing cord overheating of a power cord of the cleaner.
    Type: Grant
    Filed: June 1, 1982
    Date of Patent: May 8, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Syuji Watanabe, Yoshitaro Ishii, Masao Sunagawa
  • Patent number: D302878
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: August 15, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Shigetaka Kimura, Kohichi Hasegawa, Masao Sunagawa, Yoshitaro Ishii, Fumio Jyoraku