Ball screw pairs are circulated in two ways: internal circulation (represented by circular reverser and oval reverser) and external circulation (represented by intubation).These two structures are also the most commonly used.There is no essential difference between the performance of the two structures except that the internal circulation structure has a small connection size.Large size of mounting connection for outer circulation structure.At present, there are more than 10 kinds of ball screw pair structure, but the more commonly used mainly have the following:
Cover plate ring type (a);
External circulation formula (b);
Internal circulation formula (c);
End cover ring type (d).
(1) inner loop
Ball in the cycle process, always maintain contact with the surface of the screw cycle, called internal cycle.The advantages of the internal circulation structure are: ball screw nut shape size is small, reverse device fixed firm, rigid and not easy to wear;The reverse channel of ball screw is short, the number of ball is small, the fluidity is good, the friction loss is small, the transmission efficiency is high.Its shortcoming is the ball screw pair that cannot make it of many head thread, the return bead groove of inverter is 3 coordinate space curved surface, machining is more complex.
(2) the outer loop
External circulation is the ball ball in the cycle process, can not always maintain contact with the surface of the screw, that is, when the ball ball from the thread raceway end reverse to the beginning of the raceway and the surface of the screw out of contact.External circulation can be divided into three types: intubation type, spiral groove type and end cover type.The manufacturing process of the external circulation structure is simple and the bearing capacity is high, but it is difficult to achieve smooth pipe welding, which affects the smoothness of the ball rolling, and even leads to the imagination of ball sticking. The appearance size is large, the noise is large, and the wear resistance is poor.The internal circulation structure forms the ball circulation loop through the inverter, each inverter forms a circle of ball chain, so the bearing capacity is small, at high speed the ball fluidity is poor, suitable for micro ball screw pair and ordinary ball screw pair, but the nut size is relatively small.
[large lead end cap internal circulation ball screw pair]
The utility model relates to an internal circulation ball screw pair in the mechanical transmission technology, in particular to a large lead end cap type internal circulation ball screw pair, including a nut body, which has a thread raceway for placing the ball, and the nut body is connected to the ball screw through a ball sleeve;The two ends of the nut body are equipped with end cover circulator;A reverse channel is arranged on both end cover circulators and a circulation channel is arranged in the nut body.When the nut body, end cover type circulator, ball screw and ball ball are integrated, the thread raceway, reverse channel and circulation channel are smoothly connected to form a closed loop of ball ball.
Post time: Feb-21-2019