Toyota Shatai Kabushiki Kaisha

Yoshiaki Nagasawa

Shigeru Sakagami

Toshiaki Onoyama

Osamu Shibuki

Noboru Matsuyama

Toshihiro Andou

Katsuhiro Kawai

In a moving magnet type linear motor for automatic door of the invention, a stator fixed inside a guide rail having a substantially .andgate.-shaped cross section and a moving unit having a substantially U-shaped cross section are combined so that a height of the linear motor can be the same as that of the guide rail and the moving unit is supported slidably relative to the guide rail and fixing members of the stator has at least the both longitudinal ends or the stroke ends formed of non-magnetic conductive materials in order that the moving magnet type linear motor for automatic door produces only a low sound and is durable.

Moving magnet type linear motor for automatic door

A brushless DC linear motor includes a coil unit in which electric flow terminals of each of three flat coils are connected with a star connection or with a delta connection; and the three flat coils have the same shape whose empty core section and winding section have their dimension of breadth determined on 1/2 of a magnetic pole-pitch of a magnetic body and are arranged in a shifted position of the magnetic pole-pitch by n/3 (n is a natural number excluding multiples of 3) on the coil unit. The motor also includes a sensor unit in which three magnetic detection sensors corresponding to the respective flat coils are arranged at intervals of 1/3+2m (m=0, 1, 2, 3, . . . ) of the magnetic pole-pitch and any of these magnetic detection sensors and its corresponding flat coils are arranged at the determined distance in accordance with the magnetic pole-pitch. In accordance with the signal from each of the sensors detecting the polarity of the magnet body, an electric flow switching means transfers the electric flow polarity to three terminals of a star connection or a delta connection.

Brushless DC linear motor

A moving coil type linear motor comprises a rail of generally U-shaped cross section, permanent magnets of flat plate-shape and magnetized in the direction of thickness and provided on an inner side of the rails with varied polarities of magnetic poles next to each other. A pair of coils whose length is 1.5 times that of the magnetic pole and has a space of 0.5 times the length of the magnetic pole in the center thereof, are disposed opposingly with the permanent magnets and travel along the permanent magnets within the rail. Brushes are provided with the respective coils, and a feeder pattern arranged on an inner side of the rail, feeds electric power to the coils through the brushes, only when respective active coil parts of the coils are fully in the magnetic flux of the same direction. The linear motor also comprises sensing means for detecting signals regarding the traveling of the coils, and controlling means for controlling the travel of the coils on the ground of the signals from the sensing means.

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Toyota, Japan

Yoshiaki Nagasawa