| 摘要 |
A fluid pressure cylinder having a position detection apparatus is provided to simplify a structure of the fluid pressure cylinder without a metallic probe or a conductive member by using a cylinder tube having conductivity as a conductor of a current feedback. A fluid pressure cylinder having a position detection device includes a cylinder tube(3), a piston(4), and a magnetrostrictive type position detection apparatus(5). The piston moves linearly in the inside of the cylinder tube by the pressure operation. The magnetrostrictive type position detection apparatus detects an operation position of the piston. The magnetrostrictive type position detection apparatus has a magnetrostrictive line which is extended along the cylinder tube, and a permanent magnet which is moved to be synchronized with the piston. The position detection apparatus detects an operation position of the piston from an ultrasonic wave vibration generated in the magnetrostrictive line of a position corresponding to the permanent magnet. The cylinder tube is formed by a non-mganetic and conductive material. A hollow unit of a hole or groove shape is formed to be extended along the movement direction of the permanent magnet. The magnetrostrictive line is inserted into the hollow unit. A front unit of the magnetrostrictive line is electrically connected to the cylinder tube. |
