| 摘要 |
PURPOSE: To improve durability and geometrical accuracy of a drive cylinder by co-axially and tightly fitting a non-reinforced synthetic resin outer cylinder on the outside of a metal inner cylinder. CONSTITUTION: A cylinder 3 comprises a metal inner tube 23 such as stainless steel and a synthetic resin outer tube 24, wherein the outer tube 24 is co-axially and tightly fitted on the inner tube 23. In this case, the inner tube 23 may be formed as a thin wall stainless steel tube 26 whose inner surface 25 is precisely finished to allow a piston 7 to slide freely. Further, the outer tube 24 may be formed as a synthetic resin tube 27 so as to have the same length as that of the inner tube 23 extruded from non-reinforced synthetic resin, for example, polyvinyl chloride. Both tubes 23, 24 are fitted and fixed by pressure fitting so as to give a mutually fitted effect in the radial direction. |
