TAPPING SCREW FOR PAINT REMOVING AND MANUFACTURE THEREOF
PURPOSE:To aim at improvement of vibration resistibility and reduction of processing time by simultaneously machining, by a rolling flat dies, the twist, the projecting portion and the cutting edge portion of a tapping screw which forms intermittent projecting portions, in the radial direction of th...
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Main Author | |
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Format | Patent |
Language | English |
Published |
28.07.1989
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Subjects | |
Online Access | Get full text |
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Summary: | PURPOSE:To aim at improvement of vibration resistibility and reduction of processing time by simultaneously machining, by a rolling flat dies, the twist, the projecting portion and the cutting edge portion of a tapping screw which forms intermittent projecting portions, in the radial direction of the required portion of a shaft portion, having the cutting edge portion at the side of a screwing direction. CONSTITUTION:A top portion 4 having a crossing hole 3 is formed at one end of a shaft portion 2 and a top end portion 5 is formed at the other end 5 and intermittent projecting portions 8 are formed in a radial direction at a required portion 7 near a central portion from a neck portion 6 to a top end portion 5. A cutting edge portion 10 at the slant up-side 9 in the screwing direction of this projecting portion 8 and normal thread ridges 11a, 11b at the shaft portion except for the required portion are continuously formed. This manufacturing is conducted in a way that cold forged screw blank is rolling-machined, and forming of twist, the projecting portion and the cutting edge portion are simultaneously conducted by a dies process constructed by a movable dies and a fixed dies. Accordingly, a tapping screw for removing paint having loose stopping mechanism with small screwing torque can be obtain. And its processing time can be shortened. |
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Bibliography: | Application Number: JP19880007734 |