Screw and screwdriver for screwing and unscrewing the screw
作者： Nurlan Dauletbayev
DOI:
关键词:
摘要: The invention relates to hand tools and threaded fasteners, comprises a screw corresponding screwdriver. head working end. slot for inserting the screwdriver is made in form of “dove tail.” section screwing unscrewing as mirror image slot, with same angle slope. lengthens life screwdrivers screws their serviceability.
lens.org 参考文章(6)
Jacques Lutrat, Non-slip screw ,(1983)
Aldo Colognori, Screw, screwdriver and screw-holding attachment therefor ,(1978)
Marvin Bassell, Screw driver and screw head system ,(1980)
Richard D. Fuerle, Undercut screw and matching bit ,(2003)
Leonhard Arnold, Lorenzen Hans, Screw and driver therefor ,(1933)
Lissy John, Nonslip screw driver and screwhead ,(1951)