| 摘要 |
PURPOSE:To prevent sliding parts of a hook from wearing or seizing and to improve durability and abrasion resistance by a method wherein the sliding parts provided on both a rotating hook and a shuttle body are formed from hard ceramics with the abrasion resistance and a micro-oiling layer supplying a very small amount of a lubricant is provided between the sliding parts. CONSTITUTION:A hook for a sewing machine consists of a rotating hook 1 and a shuttle body 2, and the rotating hook 1 consists of both a rotating hook body 3 integrally formed from silicon carbide ceramics and a shuttle body presser 4. In the rotating hook body 3, a step part forming a ring-shaped groove 6 for sliding, which rotatably supports the shuttle body 2, is formed, and boss part 9 with a central hole 8 in which a hook-driving shaft 7 is fitted is also formed. The shuttle body 2 is also integrally formed from the silicon carbide ceramics. On the hook-driving shaft 7, a central hole 24 is formed and, in the central hole 24, a lubricant in an oil sump 25 is fed through a lubricating pump 26. At the end part of the hook-driving shaft 7, a control valve 32 precisely adjusting the amount of the lubricant is screwed, and the opening area of a radial hole is varied by the tapering part 35 of the control valve 32, and thus the amount of the lubricant is adjusted. |
