CN204239651U - Ball-screw apparatus - Google Patents

Abstract

The purpose of this utility model is to provide a ball screw device, which reduces the number of components by infinitely circulating the balls between the thread groove on the nut side and the thread groove on the screw shaft side assembled to the ball screw device, and Realize compact and space-saving. In particular, it aims to provide a compact ball screw device without increasing the outer diameter of the nut by providing circulation passages (end reversers) on both end surfaces of the nut. As a configuration of the end reverser type ball screw device, a nut (1) is provided on the outer peripheral surface of the screw shaft (2), and the screw groove (2a) of the screw shaft and the screw groove (1a) of the nut pass through. And form the rolling passage of ball (3). A through hole (13) extending in the axial direction of the nut (1) is formed on both axial ends of the nut (1), and is formed by an end reverser (5) connected to the two ends of the through hole The ball return path forms an infinite circulation path of the ball (3).

Description

Ball screw unit

technical field

The utility model relates to a ball screw device used in working machines and injection molding machines.

Background technique

As a conventional ball screw device, for example, a ball insertion type ball screw device as in Patent Document 1 is exemplified. The ball circulation insert of this ball screw device is arranged on the outer diameter surface of the nut, and is arranged by protruding and exposing from the side surface of the nut.

Patent Document 1: Japanese Patent Laid-Open No. 2003-269567

Utility model content

The purpose of the present invention is to reduce the number of components and achieve compactness and space saving by infinitely circulating the balls assembled between the screw groove on the nut side and the screw shaft side of the ball screw device. In particular, the object is to provide a compact ball screw device without increasing the outer diameter of the nut by providing circulation passages (end reversers) on both end surfaces of the nut.

This invention provides the following means in order to solve the said subject.

(1) An end reverser type ball screw device comprising: a nut having a spiral groove formed on an inner peripheral surface; a screw shaft having a spiral groove formed on an outer peripheral surface; the balls between the raceways formed by the helical grooves of the screw shaft; and the ball return path for returning the balls from the end point of the raceway to the beginning point, by causing the balls to roll in the raceway to keep the nut relative to the screw shaft The relative movement is characterized in that the ball return path is formed on the nut and passes through the ball return passage in the axial direction, and is formed on the end reverser connected to the two ends of the ball return passage. The curved path is formed inside the nut.

Description of drawings

FIG. 1 is a cross-sectional view of a circulation-type ball screw device according to an embodiment of the present invention.

Explanation of reference signs

1 nut

1a Helical groove of the nut

11 flange

13 The through hole that becomes the ball return passage

15 Recess for end reverser installation

2 screw shaft

2a Helical groove of screw shaft

3 balls

4 seals

5 end reverser

51 curved path

Detailed ways

FIG. 1 is a perspective cross-sectional view of a ball screw device according to this embodiment. As shown in FIG. 1 , the ball screw device of this embodiment is composed of a nut 1 , a screw shaft 2 , balls 3 , an annular seal 4 , and an end deflector 5 . A helical groove 1 a is formed on the inner peripheral surface of the nut 1 , and a helical groove 2 a is formed on the outer peripheral surface of the screw shaft 2 . Balls 3 are disposed between raceways formed by the helical groove 1 a of the nut 1 and the helical groove 2 a of the screw shaft 2 . A flange 11 is formed on one axial end of the nut 1 .

A through hole 13 extending in the axial direction is formed on the nut 1 . At both ends of the through-hole 13 of the nut 1, recesses 15 are formed in which the end reversers 5 are arranged. That is, the ball return path of this ball screw device passes through the ball return path constituted by the through hole 13 and the curved path 51 formed on the end reversers 5 connected to both ends of the ball return path, and formed inside the nut 1. The end reverser 5 uses a tangentially forward-inclining and rising-shaped structure. Seals 4 are installed at both ends of the nut 1 in the axial direction.

Claims (1)

1. an end reverser formula ball-screw apparatus, has: be formed with spiral fluted nut at inner peripheral surface; Spiral fluted lead screw shaft is formed at outer circumferential face; Be configured in the ball between the raceway that formed by the spiral chute of nut and the spiral chute of lead screw shaft; The ball return flow path of starting point is back to the terminal making ball from raceway,

Making described nut relative to lead screw shaft relative movement by making ball roll in described raceway, it is characterized in that,

Described ball return flow path by be formed on described nut and the ball current return circuit run through vertically be formed in the tangent line be connected with the two ends of this ball current return circuit and lean forward the crooked route raised up on the end reverser of shape, and be formed in the inside of nut.