Ball screw device

Abstract

The invention provides a ball screw device. The ball screw device comprises a screw shaft, a nut, a plurality of balls and a circulating member, wherein a spiral ball rolling groove is formed in the outer peripheral surface of the screw shaft; a spiral loaded ball rolling groove opposite to the ball rolling groove of the screw shaft is formed in the inner peripheral surface of the screw; the balls are located between the ball rolling groove of the screw shaft and the loaded ball rolling groove of the screw; and the circulating member is assembled on the screw, provided with a ball circulating path which enables the balls between the ball rolling groove and the loaded ball rolling groove to circulate, and also provided with a pair of guiding parts used for guiding the balls in the tangential direction of the ball rolling groove of the screw shaft and a direction changing part arranged between the pair of guiding parts and used for changing the rolling direction of the balls, and observation is carried out along the axis of the screw shaft, at least the part, close to the loaded ball rolling groove, of the pair of guiding parts are on the same tangent line relative to the ball rolling groove of the screw shaft. Therefore, the balls can be enabled to roll smoothly to realize high-speed rotation of the ball screw device, besides, the loading capacity of the ball screw device is improved, and the loading balance of the balls is favorable.

Description

technical field [0001] The present invention relates to a rolling element screw device, in particular to a circulation member for circulating rolling elements in the rolling element screw device. Background technique [0002] The ball screw unit, one of the rolling element screw units, is a mechanical element that converts rotary motion into linear motion. In order to reduce the friction when the screw shaft rotates relative to the nut, the balls roll between the ball rolling groove on the peripheral surface of the screw shaft and the loaded ball rolling groove on the inner peripheral surface of the nut facing it. A plurality of balls capable of rolling motion are arranged in the path. [0003] In order to circulate the balls between the screw shaft and the nut, a ball circulation path is provided on the nut. The balls rolling between the screw shaft and the nut are scooped up into the ball circulation path after rolling to one end of the loaded ball rolling groove of the ...

AI Technical Summary

Problems solved by technology

[0007] The rolling direction of the balls rolling on the peripheral surface of the screw shaft collides with the insert and changes abruptly to the radial direction, so the balls cannot circulate smoothly

Moreover, since the circulation part is composed of a return pipe and a pair of inserts installed at both ends in the length direction of the return pipe, the number of parts is large and the production cost is high

[0008] That is to say, in the above-mentioned insert-type circulation method, although the integral circle circulation of the ball can be realized, there is a problem of poor practicability in the smooth circulation of the ball and the manufacture of circulation components.

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