Self limiting ball screw

This utility model relates to a bidirectional fixed length limited ball screw pair, belonging to the field of screw transmission technology.
Background technology:
At present, in handheld foaming machines and fire-fighting equipment, bidirectional limit ball screw pairs are required to achieve precise quantitative feeding. However, traditional bidirectional limit ball screw pairs have complex structures, difficult processing and maintenance, and high costs; Moreover, it is necessary to use two travel switches of the peripheral device to achieve shutdown and control the nut travel. If the travel switch is damaged, the nut may exceed its travel and cause accidents, resulting in poor safety and reliability.
Technical features:
1. A bidirectional fixed length limit ball screw pair, comprising a screw (1), characterized in that: the screw (1) is provided with two symmetrical spiral grooves (2), and both ends of the two spiral grooves (2) are fixed with limit nails (5) that penetrate the screw (1) radially. The middle of the two spiral grooves (2) is provided with nuts (4), and the inner side of the nuts (4) is uniformly distributed with multiple circular straight grooves (6). A ball cage (3) is provided between the nuts (4) and the spiral grooves (2), and both ends of the ball cage (3) are provided with locking grooves that match the limit nails (5). The rolling connection on the ball cage (3) is Several ball bearings (7) corresponding to the spiral groove (2) and the circular straight groove (6).
2. The bi-directional fixed length limit ball screw pair according to claim 1, characterized in that the limit screw (5) and the screw (1) are connected by threads.
3. The bidirectional fixed length limit ball screw pair according to claim 1 or 2, characterized in that the ball (7) is a silicon nitride ceramic ball.



technical summary
This utility model belongs to the field of screw transmission technology, and specifically relates to a bidirectional fixed length limit ball screw pair, comprising a screw. The screw is provided with two symmetrical spiral grooves, and both ends of the two spiral grooves are fixed with limit screws that penetrate the screw radially. The middle of the two spiral grooves is provided with a nut, and the inner side of the nut is uniformly distributed with multiple circular straight grooves. A ball cage is provided between the nut and the spiral groove, and both ends of the ball cage are provided with card slots that match the limit screws. Several balls corresponding to the spiral groove and the circular straight groove are connected to the rolling ball cage. The bidirectional fixed length limited ball screw pair described in this utility model has a simple structure and easy maintenance. When it reaches the stroke, it can rotate freely and has high safety.

Technical R&D personnel: Yang Lianyu; Yao Zhenyu; Cui Fengqin; Su Lei
Protected technology users: Shandong Institute of Technology Precision Machinery Co., Ltd; Shandong Institute of Technology Vocational College
Technology R&D Day: December 29, 2017
Technical Release Date: August 3, 2018