| 摘要 |
PURPOSE:To detect certainly the position of a piston easily by mounting permanent magnets on a piston rod and by mounting proximity switches including magnetically sensitive elements inside on a supporting member supporting said piston rod. CONSTITUTION:A cylinder 1 is made of iron, etc. so as to sufficiently stand a high pressure. Permanent magnets 19, 20 are mounted on a piston rod 16 at the both sides of a piston 17. In mounting holes 7, 8 formed on a rod supporting member 2, 3, proximity switches 21, 22 are screwed in, while those switches detect the magnetic flux caused from said permanent magnets 19, 20 due to approach of said magnets 19, 20. Said proximity switches 21, 22 are so constructed that magnetically sensitive elements 26 are housed in cases 25 made of a non-magnetic material such as a stainless steel SUS 304, etc. Sensive surfaces 27 of said switches 21, 22 are positioned as close as possible to said permanent magnets 19, 20. |
