| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve reliability against a high pressure and to realize stability in electrical performance by constituting a cup-shaped guide for sliding and guiding a core and a cup-shaped case retaining this cup-shaped guide by a metal having one united structure. SOLUTION: A plurality of cup-shaped guides 3 each having a slender cup shape is provided in one united structure for a cup-shaped case 1 made of a metal with the overall shape formed to a cup shape. A cylindrical cover 5 is provided for a ring-shaped groove 1a of the cup-shaped case 1, and a winding 6 for a cylindrical differential transformer is provided located at the outer periphery of a cup-shaped guide 3 inside the cover 5. A lead wire 6A of a winding 6 is led out externally from the cover 5 and fixed by a filling section 20 filled by potting treatment of resin or the like. A bar-shaped core 7 is provided by inserted in the cup-shaped guide 3 in a freely slidable manner through a hole in the cup-shaped case 1, and the rear end 7a of the core 7 is projected out, and a core retaining body 10 connected to the external member 9 such as the spool shaft of a hydraulic valve having a ball bearing 8 at the rear end 7a is provided.</p> |
