US 12,230,441 B2
Transport device and transport method
Ryosuke Hoshi, Tokyo (JP); Yasuaki Aoyama, Tokyo (JP); Satoru Kaneko, Tokyo (JP); Hiroyuki Kobayashi, Tokyo (JP); Takeshi Tamakoshi, Tokyo (JP); Katsuhiro Kambara, Tokyo (JP); Hiroshi Watanabe, Tokyo (JP); and Kuniaki Onizawa, Tokyo (JP)
Assigned to HITACHI HIGH-TECH CORPORATION, Tokyo (JP)
Appl. No. 17/614,577
Filed by HITACHI HIGH-TECH CORPORATION, Tokyo (JP)
PCT Filed Apr. 7, 2020, PCT No. PCT/JP2020/015611
§ 371(c)(1), (2) Date Nov. 29, 2021,
PCT Pub. No. WO2020/255538, PCT Pub. Date Dec. 24, 2020.
Claims priority of application No. 2019-112486 (JP), filed on Jun. 18, 2019.
Prior Publication US 2022/0238267 A1, Jul. 28, 2022
Int. Cl. H01F 7/20 (2006.01); H01F 7/06 (2006.01); H01F 27/02 (2006.01); H01F 27/24 (2006.01); H01F 27/28 (2006.01)
CPC H01F 7/206 (2013.01) [H01F 7/064 (2013.01); H01F 27/02 (2013.01); H01F 27/24 (2013.01); H01F 27/28 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A transport device comprising:
a first magnetic body provided on a side of a to-be-transported object;
a plurality of magnetic circuits, each of the plurality of magnetic circuits comprises a core consisting of a second magnetic body, and a winding around the outside of the core; and
a plurality of drive circuits, each of the plurality of drive circuits configured to supply a current to the winding of a different one of the plurality of magnetic circuits in such a manner as to cause an attractive or repulsive electromagnetic force between the plurality of magnetic circuits and the first magnetic body,
wherein a diameter of the first magnetic body is less than a diameter of any one of the plurality of magnetic circuits, which comprise the core and the winding around the outside of the core,
wherein the plurality of magnetic circuits are disposed in a linear array along a direction of travel of the first magnetic body such that the second magnetic bodies form a plane along which the first magnetic body is to be positioned,
wherein a first magnetic circuit is one of the plurality of magnetic circuits and a second magnetic circuit is another of the plurality of magnetic circuits which is adjacent to the first magnetic circuit in the direction of travel of the first magnetic body,
wherein in a case where predetermined currents with the same absolute value are applied to the first magnetic circuit and the second magnetic circuit in such a manner as to cause a repulsive electromagnetic force between the first magnetic body and the first magnetic circuit, and to cause an attractive electromagnetic force between the first magnetic body and the second magnetic circuit,
when the first magnetic body is located between the first magnetic circuit and a first predetermined position, an absolute value of an electromagnetic attraction force to the first magnetic body which is produced by the second magnetic circuit is larger than an absolute value of an electromagnetic repulsive force with respect to the first magnetic body which is produced by the first magnetic circuit,
when the first magnetic body is located at the first predetermined position, an absolute value of an electromagnetic attraction force to the first magnetic body which is produced by the second magnetic circuit is equal to an absolute value of an electromagnetic repulsive force with respect to the first magnetic body which is produced by the first magnetic circuit, and
when the first magnetic body is located between the first predetermined position and the second magnetic circuit, an absolute value of an electromagnetic attraction force to the first magnetic body which is produced by the second magnetic circuit is smaller than an absolute value of an electromagnetic repulsive force with respect to the first magnetic body which is produced by the first magnetic circuit, and
wherein in a case where the first magnetic body is located on a side of the first magnetic circuit relative to the first predetermined position, the plurality of drive circuits mainly supply a current to a winding of the second magnetic circuit in such a manner that an electromagnetic attraction force which is produced between the first magnetic body and the second magnetic circuit becomes a main thrust,
wherein in a case where the first magnetic body is located on a side of the second magnetic circuit relative to the first predetermined position, the plurality of drive circuits mainly supply a current to a winding of the first magnetic circuit in such a manner that an electromagnetic repulsive force which is produced between the first magnetic body and the first magnetic circuit becomes a main thrust,
wherein in a case where the movement of the first magnetic body is initiated, the drive circuit of the second magnetic circuit supplies a current to the winding of the second magnetic circuit in such a manner that an electromagnetic attraction force is produced between the first magnetic body and the second magnetic circuit as a thrust to initiate the movement of the first magnetic body in the direction of travel, and
wherein the first predetermined position is a position where an absolute value of the electromagnetic repulsive force generated by the first magnetic circuit and an absolute value of the electromagnetic attraction force generated by the second magnetic circuit become equal.