Ball screw device

Abstract

A ball screw device capable of providing excellent acoustic performance even when a screw shaft or a nut is rotated at a high speed. Where the diameter of a ball 16 is Dw and the diameter of a ball returning through passage 17 formed in the nut 13 is D1, the ball returning through passage 17 is formed in the nut 13 so that the requirement of (D1- Dw) <= 0.1 Dw is satisfied. Also, where the diameter of the ball 16 is Dw and the diameter of a ball rolling passage 19 formed in a ball rolling member 18 is D2, the ball rolling passage 19 is formed in the ball rolling member 18 so that the requirement of (D2 - D2) <= 0.1 Dw can be satisfied.

Description

technical field [0001] The present invention relates to an improvement as a ball screw device for converting rotary motion into linear motion. Background technique [0002] A ball screw device used in a conveyance mechanism of a machine tool, etc. includes a screw shaft, a nut having a ball screw groove on an inner diameter surface opposite to a ball screw groove formed on an outer diameter surface of the screw shaft, and the nut and the above-mentioned nut. A plurality of balls that roll along the ball-loaded rolling path formed between the ball screw grooves of the screw shaft as the screw shaft or nut rotates. [0003] The nut of such a ball screw device, for example, moves relatively linearly in the axial direction of the screw shaft as the balls roll in the ball-loaded rolling path as the screw shaft rotates. However, in order to continue the relative linear motion of the nut, it is necessary to The balls rolling in the ball load rolling path repeatedly roll in the bal...

AI Technical Summary

Problems solved by technology

[0006] In such a ball screw device, it is easier to suppress the occurrence of noise, vibration, etc., compared with the use of a ball circulation tube. However, if the ratio of the diameter of the ball return passage to the ball diameter is too large, the ball return passage will be damaged. The clearance of the ball (the amount of clearance between the ball return through passage and the ball) becomes larger

Therefore, the arrangement of the balls in the ball return passage tends to meander, and the balls in the ball return passage advance while colliding with the inner surface of the ball return passage when the screw shaft or the nut rotates at high speed, resulting in poor acoustic performance. question

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