| 摘要 |
1,105,275. Screws. NORMALIZED BOLTS Ltd. 18 Nov., 1966 [23 Nov., 1965; 9 March, 1966; 23 March, 1966], Nos. 49618/65, 10259/66 and 12770/66: Heading F2H. [Also in Division B3] A paint-removing screw is formed with a spigot 23 and at least one groove 27 of tapering or part-circular cross-section 52. The side edge of the groove leading inwards from the paintremoving edge lies in a plane, or is tangential to a plane 54, inclined at an angle a of 30- 45 degrees to the radial plane 55 through the paint-removing edge. Alternatively, asymmetrical grooves 57 may be employed. A washer may be slipped on to the shank of the screw before the thread is rolled thereon so that it is trapped between the head and the thread. |
