US 5,183,980 AGranted

Linear motor elevator device with a null-flux position adjustment

AssigneeMitsubishi Denki Kabushiki Kaisha

InventorsShigeru Okuma, Takeshi Furuhashi, Hiroyuki Ikejima, Toshiaki Ishii

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Abstract

A linear motor elevator includes: a multitude of primary side coils mounted on the hoist way along the whole hoist path, and vertical columns of permanent magnets constituting the secondary side magnets mounted on the elevator car. The polarity of the permanent magnets alternate both horizontally across the columns and vertically along respective columns. When the elevator car is displaced horizontally in a direction perpendicular to the hoisting direction of the elevator car, a circulating current producing a magnetic flux that counterbalances the variation of the flux caused by the displacement flows through each primary side coils opposing the permanent magnets on the elevator car. Thus, the position of the elevator car within the hoist way is automatically adjusted in accordance with the null-flux method.

Claims4

Dependent claims

A linear motor elevator device for hoisting a hoisted body up and down within a hoist way by means of a linear motor, comprising:

primary side coils of a linear motor mounted on a side wall of said hoist way along a hoist path of the hoisted body, the primary side coils generating a magnetic field moving along the hoist way;
and
secondary side magnets of the linear motor attached to a side of said hoisted body to oppose said primary side coils across a gap, whereby said moving magnetic field generated by the primary side coils drive said hoisted body within the hoist way;
wherein upon displacement of the hoisted body along a direction perpendicular to a hoisting direction of the hoisted body a circulating current which counterbalances a variation of magnetic flux caused by the displacement of the hoisted body flows through said primary side coils, thereby automatically adjusting a position of the hoisted body along said direction perpendicular to the driving direction.

1 more element

Dependencies are inferred from the claim text.