GB169227A - Improvements relating to screw-and-nut devices - Google Patents

Abstract

169,227. Hazelton, G. June 15, 1920. Screw-and-nut mechanism.-Relates to screw- and-nut mechanism with interrupted threads to permit of longitudinal or rotational adjustment as desired, the nut member comprising two parts adapted to be rotated relatively to align the threaded parts when longitudinal motion is required or to dis-align the threaded parts so that they function as a complete nut for rotary adjustment. The invention comprises an arrangement in which the two nut elements are so mechanically connected that relative movement is only possible along a spiral path having a pitch equivalent to that of the interrupted threads. In the arrangement shown in Figs. 4 and 6, nut members 2, 3, with interrupted threads 2<a>, 3<a>, are connected together by a screw-thread 2<c>. The nut members may be arranged out of direct contact with one another in a single member or device 9, Fig. 7, or in separate members or devices fixed relatively to each other. One of the nut members is connected to the part 9 by a screw-thread 2<c>, whilst the other nut member is fixed by means of a stud 11. In a modification shown in Fig. 9, the parts 2, 3 held by a yoke 15 are formed with external interrupted threads, co-operating with a rack member 1, the gaps in the threads being brought into alignment bers may be limited by a spring-pressed pin in one when required. Relative rotation of the nut mempart engaging a shallow groove with end recesses in the other part.