SU1216511A1 - Screw reversing mechanism - Google Patents

Description

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The invention relates to mechanical engineering and instrument making and can be used in various devices for converting reciprocating motion into continuous rotational motion and vice versa.

The aim of the invention is to simplify the design by removing the device for converting the nut from one thread to another.

FIG. 1 shows a screw mechanism, a general view; at 4 "g. 2 - mutually polished screw turns. and nuts in motion transmission and revolving.

The screw mechanism contains a screw 1, on which the two upper half-turns are made. - right 2 and left 3 and two lower semi-turns - right 4 and left 5, and nut t with right 6 and left 7 semi-turns. Semi-turns can either be closed or open. Between the upper and lower half-turns there is a gap 8, a slightly larger distance required to accommodate the half-turn nut.

Screw reversing mechanism works as follows.

For convenience of reviewing the process of operation of the mechanism, helixes are scanned onto a plane. The lines indicate the direction of the angular velocity u) r, the direction of the linear velocity of the screw Vg, and the sliding speed of the turns of the nut relative to the turns of the screw.

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When the screw 1 is moved upwards (Fig. 2), the force of the lower half-thread 4 of the screw 1 acts on the half-turn 6 of the nut, causing the latter to rotate in the direction indicated by the arrow (the arrow is located between the observer and the mechanism). When this happens, the coils 5 and Z converge, and at the moment of their contact (Fig. 2) the screw g stops. With an instantaneous change of direction, the force F starts moving the screw down, the nut continues to rotate by inertia. After selecting the axial gap between the screw half-screw and nut half-screw 3 screws, the screw 7 begins to act on the half-thread, maintaining the initial rotation.

If the change in the voltage of the force F lags behind the moment the screw is stopped, then in the initial period the turn 7 of the nut moving by inertia acts on the half turn of the screw 5, causing the latter to move downwards. Subsequently, when the direction changes, the force F enters the hook-; half-turn 7 and 3, and the movement continues.

When the reverse is in the lowest position, semi-turns 2 and 6 (Fig. 2d) first interact, and then semi-turns $ and 4 (Fig. 2o), after which lifting goes up and the cycle repeats.

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VNIIPI Order 983/45 Circulation 880 Subscription Branch RTTP Patent, Uzhgorod, ul. Project, 4

Claims (1)

A SCREW REVERSE MECHANISM comprising a screw with right and left thread threads and a nut interacting with it, characterized in that, in order to simplify the design by removing the device for transferring the nut from one thread to another, two turns of the screw are located with a longitudinal gap between them, and each the turn is formed by two half-turns of the right and left threads, the nut size is. puppy in the longitudinal gap and has the corresponding half-turn of the right and left threads. from SU.,., 1216511>