| 摘要 |
PROBLEM TO BE SOLVED: To drive a piston with a permanent magnet being molded easily. SOLUTION: Planar permanent magnets 20 are arranged to surround a piston 15 thus constituting a magnet group 18. An electromagnetic coil 19 is applied over the outer circumference of the magnet group 18 and fed with an AC current to generate an AC field in order to move the magnet group 18 in the axial direction thus reciprocating the piston 15 in an inner cylinder 7 in the axial direction. Since planar permanent magnets 20 are employed, molding work thereof is facilitated while suppressing warp or distortion.
|
