The failure phenomenon and specific reasons of ball screw pair in operation are as follows:

1、反向間隙大，定位精度差，加工零件尺寸不穩(wěn)定。

1. Large reverse clearance, poor positioning accuracy and unstable dimension of machined parts.

滾珠絲杠副及其支撐系統(tǒng)由于長時間運行產(chǎn)生的磨損間隙，將直接影響數(shù)控機(jī)床的傳動精度和剛性。一般故障現(xiàn)象有反向間隙大、定位精度不穩(wěn)定等問題。根據(jù)磨損具體產(chǎn)生的位置，故障原因可分為以下幾類：提高滾珠絲桿副精度的辦法？ 滾珠絲杠支撐軸承磨損或軸承預(yù)加負(fù)荷墊圈配的不合適。滾珠絲杠雙螺母副產(chǎn)生間隙、滾珠磨損。

The wear clearance of ball screw pair and its support system caused by long-time operation will directly affect the transmission accuracy and rigidity of CNC machine tools. The common faults include large reverse clearance and unstable positioning accuracy. According to the specific location of wear, the causes can be divided into the following categories: how to improve the accuracy of ball screw pair? The ball screw support bearing is worn or the preloading washer is not suitable. The double nut pair of ball screw produces clearance and ball wear.

2、滾珠絲杠副運動不平穩(wěn)，噪音過大。伺服電機(jī)驅(qū)動參數(shù)未調(diào)整好。絲杠絲母潤滑不好。滾珠絲杠彎曲變形。

2. The motion of the ball screw pair is not stable and the noise is too large. Servo motor drive parameters are not adjusted well. The screw nut is not well lubricated. The ball screw is bent and deformed.

滾珠絲桿副的常見故障如下：

The common faults of ball screw pair are as follows:

（1）過載問題

(1) Overload problem

滾珠絲桿副進(jìn)給傳動的潤滑狀態(tài)不好、軸向預(yù)加載荷太大、絲杠與導(dǎo)軌不平行、螺母軸線與導(dǎo)軌不平行、絲杠彎曲變形時，都會引起過載警聲。一般會在CRT上顯示伺服電動機(jī)過載、過熱或過流的警聲，或在電柜的進(jìn)給驅(qū)動單元上，用指示燈或數(shù)碼管提示驅(qū)動單元過載、過流信息。

When the lubrication state of the ball screw pair feed drive is not good, the axial preload is too large, the lead screw is not parallel to the guide rail, the nut axis is not parallel to the guide rail, and the lead screw is bent and deformed, the overload alarm will be caused. Generally, the alarm sound of overload, overheating or over-current of servo motor will be displayed on CRT, or the information of overload and over-current of drive unit will be prompted by indicator light or nixie tube on the feed drive unit of electric cabinet.

（2）爬行問題

(2) Crawling problem

爬行問題一般發(fā)生在啟動加速段或低速進(jìn)給時，多因進(jìn)給傳動鏈的潤滑狀態(tài)不好、外加負(fù)載過大等因素所致。尤其要注意的是，伺服電動機(jī)和滾珠絲杠連接用的聯(lián)軸器，如連接松動或聯(lián)軸器本身缺 陷，如裂紋等，會造成滾珠絲杠轉(zhuǎn)動和伺服電動機(jī)的轉(zhuǎn)動不同步，從而使進(jìn)給運動忽快忽慢，產(chǎn)生爬行現(xiàn)象。

The creeping problem usually occurs when the acceleration section or low speed feed is started, which is mainly caused by the bad lubrication state of the feed transmission chain and the excessive load. In particular, if the coupling used for connecting the servo motor and the ball screw is loose or the coupling itself is defective, such as cracks, etc., it will cause the rotation of the ball screw and the servo motor to be out of sync, so that the feed movement will be fast and slow, and the phenomenon of crawling will occur.

（3）竄動問題

(3) The problem of movement

竄動問題是滾珠絲杠副進(jìn)給傳動的潤滑狀態(tài)不好、絲杠支承軸承的壓蓋壓合情況不好、滾珠絲杠副滾珠有破損、絲杠支承軸承可能破裂、軸向預(yù)加載荷太小，使進(jìn)給傳動鏈的傳動間隙過大，引起絲杠傳動時的軸向竄動。

The problem of shifting is that the lubrication state of the feed transmission of the ball screw pair is not good, the gland pressing of the ball screw support bearing is not good, the ball of the ball screw pair is damaged, the ball screw support bearing may break, and the axial preload is too small, which makes the transmission clearance of the feed transmission chain too large and causes the axial shifting of the ball screw drive.