Patents by Inventor Takato Doi

Takato Doi 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: 6476524
    Abstract: A moving-coil linear motor free of cogging. The motor has a rotor (3) including separated block cores (31, 32 and 33), each of which has a length equivalent to eight times the magnet pitch (Pm) and includes nine teeth (4) along the length. The block cores are arranged in line and separated by gaps equivalent to ⅔ of the magnet pitch. The first block (31) is divided into three groups of teeth (4) with armature coils (5) to form U-, V- and W-phases. Similarly, the second block (32) is grouped to form V-, W- and U-phases, and the third block (33) is grouped to form W-, U- and V-phases. The armature coils (5) are formed to differ in phase by 120 degrees from one another in order to zero the sum of the cogging caused by the blocks.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: November 5, 2002
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Yasuhiro Miyamoto, Kazuhiro Maekawa, Takato Doi, Masaki Hisatsune
  • Patent number: 6407471
    Abstract: The invention relates to a linear motor which is provided with a row of permanent magnets 6a, 6b, 6c, . . . for a field system, and an armature 2 facing the same via a magnetized space in an orthogonal direction thereto, wherein the armature core 3 has a winding accommodation groove 3a formed at both sides of armature iron plates produced by punching out oriented electromagnetic steel plate so as to become rectangular, and convex and concave engagement portions 3b and 3c, the armature iron plates are laminated to constitute one core block, and at the same time, the lengthwise direction, orthogonal to the permanent magnet row, in the respective core blocks is made the same as the rolling direction of electromagnetic steel plates. Thereby, since the magnetic flux of the armature winding 4 flows along the rolling direction of the core blocks, the magnetic flux density can be increased, and the peak thrust can be also increased.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: June 18, 2002
    Assignee: Kabushiki Kaisha Yaskawa Denki
    Inventors: Yasuhiro Miyamoto, Masaki Hisatsune, Kazuhiro Maekawa, Takato Doi, Masahiko Tanabe