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導軌絲杠:精密傳動界的扛把子,聊聊滾珠絲桿的那些事

來源:http://m.pet998.com/ 日期:2026-04-24 發布人:

  今天從滾珠絲桿的特點、組成和分類、幾種安裝方式和主要參數入手,咱們詳細的聊一聊滾珠絲桿的那些事兒。

  Today, starting from the characteristics, composition and classification, several installation methods and main parameters of ball screws, let's talk in detail about those things related to ball screws.

  關于滾珠絲桿的介紹,百度百科的內容是以下解說:

  Regarding the introduction of ball screws, the content of Baidu Baike is as follows:

  滾珠絲杠是將回轉運動轉化為直線運動,或將直線運動轉化為回轉運動的理想的產品。

  Ball screws are ideal products for converting rotary motion into linear motion, or converting linear motion into rotary motion.

  滾珠絲杠是工具機械和精密機械上常使用的傳動元件,其主要功能是將旋轉運動轉換成線性運動,或將扭矩轉換成軸向反復作用力,同時兼具高精度、可逆性和率的特點。由于具有很小的摩擦阻力,滾珠絲杠被廣泛應用于各種工業設備和精密儀器。簡單來說,滾珠絲桿就是可以由旋轉運動轉化為直線運動或者由直線運動轉換為旋轉運動的機構,但是一般對它的應用都是由旋轉運動轉換為直線運動。

  Ball screw is the most commonly used transmission component in tool machinery and precision machinery. Its main function is to convert rotational motion into linear motion or torque into axial repetitive force, while also possessing the characteristics of high precision, reversibility, and high efficiency. Due to its low frictional resistance, ball screws are widely used in various industrial equipment and precision instruments. Simply put, a ball screw is a mechanism that can convert rotational motion into linear motion or from linear motion to rotational motion, but its general application is to convert rotational motion into linear motion.

  滾珠絲桿的特點

  Characteristics of ball screw

  1.摩擦損失小、傳動效率高由于滾珠絲杠副的絲杠軸與絲杠螺母之間有很多滾珠在做滾動運動,所以能得到較高的運動效率。與過去的滑動絲杠副相比驅動力矩達到1/3以下,即達到同樣運動結果所需的動力為使用滑動絲杠副的1/3。在省電方面很有幫助。2.精度高滾珠絲杠副是一般是用世界水平的機械設備連貫生產出來的,特別是在研削、組裝、檢查各工序的工廠環境方面,對溫度、濕度進行了嚴格的控制,由于完善的品質管理體制使精度得以充分保證。3.高速進給和微進給可能滾珠絲杠副由于是利用滾珠運動,所以啟動力矩極小,不會出現滑動運動那樣的爬行現象,能保證實現精確的微進給。4.軸向剛度高滾珠絲杠副可以加與預壓,由于預壓力可使軸向間隙達到負值,進而得到較高的剛性(滾珠絲杠內通過給滾珠加予壓力,在實際用于機械裝置等時,由于滾珠的斥力可使絲母部的剛性增強)。5.不能自鎖、具有傳動的可逆性滾珠絲桿的組成和分類

  1. Low friction loss and high transmission efficiency. Due to the rolling motion of many balls between the screw shaft and screw nut of the ball screw pair, high motion efficiency can be achieved. Compared with the past sliding screw pair, the driving torque reaches less than 1/3, which means that the power required to achieve the same motion result is 1/3 of using a sliding screw pair. It is very helpful in terms of power saving. 2. High precision ball screw pairs are generally produced using the world's highest level of mechanical equipment, especially in the factory environment of grinding, assembly, and inspection processes, with strict control of temperature and humidity. Due to a sound quality management system, accuracy is fully guaranteed. 3. High speed feed and micro feed may use ball screw pairs that utilize ball motion, resulting in extremely low starting torque and no crawling phenomenon like sliding motion, ensuring precise micro feed. 4. High axial stiffness ball screw pairs can be preloaded, as preloading can cause negative axial clearance, resulting in higher rigidity (by applying pressure to the ball inside the ball screw, in practical use in mechanical devices, the repulsive force of the ball can enhance the rigidity of the female part). 5. Composition and classification of reversible ball screws that cannot self lock and have transmission

  滾珠絲杠由螺桿、螺母、鋼球、預壓片、反向器和防塵器組成。它的功能是將旋轉運動轉化成直線運動,這是艾克姆螺桿的進一步延伸和發展,這項發展的重要意義就是將軸承從滑動動作變成滾動動作。由于具有很小的摩擦阻力,滾珠絲杠被廣泛應用于各種工業設備和精密儀器。關于滾珠絲桿,種類太多了,這里咱們就列舉幾種比較常見的。1.自潤式滾珠絲桿:具有可拆換除油裝置的自潤式滾珠絲桿,不需要潤滑管路系統與設備,減少了換油和廢油處理成本。2.靜音式滾珠絲桿:它的原理是在滾珠之間設置有特殊溝型的滾珠間隔環,可以抑制住滾珠與滾珠之間碰撞所產生的噪音,使滾珠絲桿在運動的時候更加的安靜、平順。3.高速化滾珠絲桿:具有高加速、高剛性、高速進給、低振動、低噪音的特點。使用在工具機的快速進給,磨具高速切削中心機和高速縱荷切削中心等領域。4.重負荷型滾珠絲桿:能夠承受較大的軸向負荷,適用于全電式設計機、空壓機、半導體制造裝置和鍛壓制造裝置等。還有軋制和研磨級絲桿的區分,軋制絲桿的精度相對低一點,適用于精度要求不是很高的場合;而研磨級絲桿,根據它的名稱也可以看的出來,精度比較高,適合精度要求高的場合。而根據螺母中的滾珠循環方式,可以分為外循環、內循環、端蓋式。先說一下端蓋式,這種是比較早期的結構,但是缺點比較明顯,現在基本已經被淘汰了,用到的很少,所以這里就稍微提一下。關于內外循環螺母的具體構造咱們就不聊了,畢竟咱們不需要造絲桿,只需要知道兩者的區別以及各自的優缺點就可以。

  A ball screw consists of a screw, nut, steel ball, pre press plate, reverser, and dust collector. Its function is to convert rotational motion into linear motion, which is a further extension and development of the Ekm screw. The significance of this development is to transform bearings from sliding motion to rolling motion. Due to its low frictional resistance, ball screws are widely used in various industrial equipment and precision instruments. There are too many types of ball screws, here we will list a few of the more common ones. 1. Self lubricating ball screw: A self lubricating ball screw with a detachable oil removal device that does not require lubrication of pipeline systems and equipment, reducing the cost of oil change and waste oil treatment. 2. Silent ball screw: Its principle is to set a special groove type ball spacer ring between the balls, which can suppress the noise generated by the collision between the balls, making the ball screw quieter and smoother during movement. 3. High speed ball screw: characterized by high acceleration, high rigidity, high-speed feed, low vibration, and low noise. Used in fields such as rapid feed of machine tools, high-speed cutting centers for grinding tools, and high-speed longitudinal load cutting centers. 4. Heavy duty ball screw: capable of withstanding large axial loads, suitable for fully electric design machines, air compressors, semiconductor manufacturing equipment, forging manufacturing equipment, etc. There is also a distinction between rolling and grinding grade screws. Rolling screws have relatively lower accuracy and are suitable for situations where precision requirements are not very high; And the grinding grade screw, according to its name, can also be seen that it has high precision and is suitable for occasions with high precision requirements. According to the ball circulation method in the nut, it can be divided into external circulation, internal circulation, and end cap type. Let's first talk about the bottom cover type. This is an early structure, but its drawbacks are quite obvious. It has been basically eliminated and is rarely used, so I will briefly mention it here. We won't talk about the specific structure of the inner and outer loop nuts, after all, we don't need to make screws, we just need to know the differences between the two and their respective advantages and disadvantages.

  滾珠絲桿的幾種安裝方式

  Several installation methods of ball screw

  一般的安裝方式,就是以上的四種,大家可以根據自己的使用工況,選擇絲桿的安裝方式,而不同的安裝方式,絲桿兩端也是不同的。滾珠絲桿的主要參數

  The general installation methods are the four types mentioned above. You can choose the installation method of the screw rod according to your own operating conditions, and the two ends of the screw rod are also different for different installation methods. Main parameters of ball screw

  說到滾珠絲桿的選型,需要先來說一下它的常用參數,然后才能從這些參數下手,確定它的型號。1.公稱直徑即絲杠的外徑,常見規格有12、14、16、20、25、32、40、50、63、80、100、120,不過請注意,這些規格中,各廠家一般只備16~50的貨,也就是說,其他直徑大部分都是期貨(見單生產,貨期大約在30~60天,日系產品大約是2~2.5個月,歐美產品大約是3~4個月)。公稱直徑和負載基本成正比,直徑越大的負載越大,具體數值可以查閱廠家產品樣本。這里只說明兩個概念:動額定負荷與靜額定負荷,前者指運動狀態下的額定軸向負載,后者是指靜止狀態下的額定軸向負載。設計時參考前者即可。需要注意的是,額定負荷并非負荷,實際負荷與額定負荷的比值越小,絲杠的理論壽命越高。:直徑盡量選16~63。2.導程導程指的是絲桿旋轉一周,螺母直線運動的距離。常見的導程有(單位:mm):2、4、5、6、8、10、16、20、25、32、40,跟導程有關系的參數是螺母運動速度和滾珠絲桿可提供的直線推力。

  When it comes to the selection of ball screw, it is necessary to first talk about its common parameters, and then start from these parameters to determine its model. 1. The nominal diameter refers to the outer diameter of the lead screw. Common specifications include 12, 14, 16, 20, 25, 32, 40, 50, 63, 80, 100, and 120. However, please note that among these specifications, manufacturers generally only stock goods with a size of 16-50. This means that most other diameters are futures (produced on a per order basis with a lead time of approximately 30-60 days, Japanese products with a lead time of approximately 2-2.5 months, and European and American products with a lead time of approximately 3-4 months). The nominal diameter is basically proportional to the load, and the larger the diameter, the greater the load. Specific values can be found in the manufacturer's product samples. Here, only two concepts are explained: dynamic rated load and static rated load. The former refers to the rated axial load in motion, while the latter refers to the rated axial load in static state. You can refer to the former when designing. It should be noted that the rated load is not the maximum load, and the smaller the ratio of actual load to rated load, the higher the theoretical life of the screw. Recommendation: Choose a diameter of 16~63 as much as possible. 2. Lead refers to the distance that the screw rotates once and the nut moves in a straight line. The common lead values (in mm) are 2, 4, 5, 6, 8, 10, 16, 20, 25, 32, and 40. The parameters related to the lead values are the speed of the nut movement and the linear thrust that the ball screw can provide.

  導程越大,相同轉速情況下,直線運動速度越快,具體的計算關系為:v=ri。其中v——螺母的移動速度(單位:mm/s);r——絲桿的旋轉速度(單位:r/s);i——導程(單位:mm)。導程和絲桿推力的關系:F=(2πTn)/i。其中F——絲桿推力(單位:N);T——電機提供的扭矩(單位N·m);n——傳動效率(滾珠絲桿的傳動效率一般為85%~95%);i——導程(這里的單位是m)。3.長度

  The larger the lead, the faster the linear motion speed under the same rotational speed. The specific calculation relationship is: v=ri. Among them, v - the moving speed of the nut (unit: mm/s); R - Rotation speed of the screw (unit: r/s); I - Lead (unit: mm). The relationship between lead and screw thrust: F=(2 π Tn)/i. Among them, F - screw thrust (unit: N); T - torque provided by the motor (unit: N · m); N - Transmission efficiency (the transmission efficiency of ball screw is generally 85%~95%); I - lead (unit here is m). 3. Length

  長度有兩個概念,一個是全長,另一個是螺紋長度。有些廠家只計算全長,但有些廠家需要提供螺紋長度。螺紋長度中也有兩個部分,一個是螺紋全長,一個是有效行程。前者是指螺紋部分的總長度,后者是指螺母直線移動的理論長度,螺紋長度=有效行程+螺母長度+設計裕量(如果需要安裝防護罩,還要考慮防護罩壓縮后的長度,一般按防護罩長度的1/8計算)。

  There are two concepts of length, one is the total length, and the other is the thread length. Some manufacturers only calculate the total length, while others require the thread length to be provided. There are also two parts in the thread length, one is the total length of the thread and the other is the effective stroke. The former refers to the total length of the threaded part, while the latter refers to the theoretical maximum length of the nut's linear movement. Thread length=effective stroke+nut length+design margin (if a protective cover needs to be installed, the length of the protective cover after compression should also be considered, generally calculated as 1/8 of the maximum length of the protective cover).

  在設計繪圖時,絲杠的全長大致可以按照一下參數累加:絲杠全長=有效行程+螺母長度+設計余量+兩端支撐長度(軸承寬度+鎖緊螺母寬度+裕量)+動力輸入連接長度(如果使用聯軸器則大致是聯軸器長度的一半+裕量)。特別需要注意的是,如果你的長度超長(大于3米)或長徑比很大(大于70),事先咨詢廠家銷售人員可否生產,總體的情況是,國內廠家常規品長度3米,特殊品16米,國外廠家常規品6米,特殊品22米。當然不是說國內廠家就不能生產更長的,只是定制品的比較離譜。:長度盡量選6米以下,超過的用齒輪齒條更劃算了。

  When designing drawings, the total length of the screw can be roughly accumulated according to the following parameters: screw total length=effective stroke+nut length+design allowance+support length at both ends (bearing width+locking nut width+allowance)+power input connection length (if a coupling is used, it is roughly half of the coupling length+allowance). It is particularly important to note that if your length is too long (greater than 3 meters) or the aspect ratio is large (greater than 70), it is best to consult with the manufacturer's sales personnel in advance to see if they can produce it. The overall situation is that the maximum length for regular products from domestic manufacturers is 3 meters, for special products it is 16 meters, for regular products from foreign manufacturers it is 6 meters, and for special products it is 22 meters. Of course, it's not that domestic manufacturers can't produce longer ones, it's just that the prices of customized products are quite outrageous. Recommendation: Choose a length of less than 6 meters as much as possible, and for lengths exceeding this, it is more cost-effective to use gears and racks.

  4.螺母形式

  4. Nut form

  各廠家的產品樣本上都會有很多種螺母形式,一般型號中的前幾個字母即表示螺母形式。按法蘭形式分大約有圓法蘭、單切邊法蘭、雙切邊法蘭和無法蘭幾種。按螺母長度分有單螺母和雙螺母(注意,單螺母和雙螺母沒有負載和剛性差異,這一點不要聽從廠家銷售人員的演說,單螺母和雙螺母的主要差異是后者可以調整預壓而前者不能,另外后者的和長度大致均是前者的2倍)。在安裝尺寸和性能允許的情況下,設計者在選用時應盡量選擇常規形式,以避免維護時備件的貨期問題。:頻繁動作、高精度維持場合選雙螺母,其他場合選雙且邊單螺母。:螺母形式盡量選內循環雙切邊法蘭單螺母。

  There are many types of nut forms on the product samples of various manufacturers, and the first few letters in the general model indicate the nut form. According to the form of flanges, there are approximately several types: circular flanges, single cut edge flanges, double cut edge flanges, and non flange flanges. According to the length of the nut, there are single nuts and double nuts (note that there is no difference in load and rigidity between single nuts and double nuts, do not listen to the manufacturer's salesperson's speech on this point. The main difference between single nuts and double nuts is that the latter can adjust the preload while the former cannot, and the price and length of the latter are roughly twice that of the former). When the installation size and performance allow, designers should try to choose conventional forms as much as possible to avoid the problem of spare parts delivery time during maintenance. Recommendation: Choose double nuts for frequent movements and high-precision maintenance occasions, and double and single nuts with edges for other occasions. Recommendation: For nut types, try to choose inner circulation double cut flange single nuts.

  5.精度

  5. Accuracy

  滾珠絲桿,按國內分類,精度等級有P1、P2、P3、P4、P5、P7、P10,日本、韓國,還有臺灣省采用JIS等級,即C0、C1、C2、C3、C5、C7、C10;歐洲的標準采用的是IT0,IT1, IT2,IT3,IT4,IT5,IT7,IT10。一般,像我們公司采購的都是臺灣的滾珠絲桿,性價比比較高,再其次是日本的。精度表示方法為:不論你的滾珠絲桿有多長,任取一段300mm,誤差都在等級代表的精度之內,各等級代表的精度如下。一般來說,普通機械采用C7,C10級,數控設備一般采用C5,C3級(C5較多,國內大部分數控機床都是C5級),航空制造設備,精密投影及三坐標測量設備等一般采用C3,C2精度。另外,C7,C10級一般采用軋制方法制造,C5級及以上采用研磨方法制造。綜上所述,非標設計常用的滾珠絲桿精度等級為C7()軋制方法制造或有些人稱為轉造),而對滾珠絲桿精度等級有更高的要求的,C5(研磨方法制造)也夠用了。當然還是要說一句要具體問題具體分析。

  Ball screw rod, classified domestically, has precision grades of P1, P2, P3, P4, P5, P7, P10. Japan, South Korea and Taiwan, China Province of China use JIS grades, namely C0, C1, C2, C3, C5, C7, C10; The standards adopted by European countries are IT0, IT1, IT2, IT3, IT4, IT5, IT7, and IT10. Generally, our company purchases ball screws from Taiwan, which have a relatively high cost performance ratio, followed by those from Japan. The accuracy representation method is: no matter how long your ball screw is, any 300mm section will have an error within the accuracy represented by the grade. The accuracy represented by each grade is as follows. Generally speaking, ordinary machinery adopts C7 and C10 levels, while CNC equipment generally adopts C5 and C3 levels (C5 is more common, and most domestic CNC machine tools are C5 level). Aviation manufacturing equipment, precision projection and coordinate measuring equipment generally adopt C3 and C2 accuracy. In addition, C7 and C10 grades are generally manufactured using rolling methods, while C5 grades and above are manufactured using grinding methods. In summary, the commonly used precision level for non-standard designs of ball screws is C7 (manufactured by rolling method or some people refer to it as conversion), while C5 (manufactured by grinding method) is also sufficient for those with higher requirements for the precision level of ball screws. Of course, it is necessary to analyze the specific issues on a case by case basis.

  6.預壓等級也叫預緊,關于預壓,我們不用了解具體的預緊力和預緊方式,只需要按照廠家樣本選擇預壓等級就可以了。預壓等級越高,螺母與螺桿配合越緊;反之,等級越低越松。遵循的原則是: 大直徑、雙螺母、高精度、驅動力矩較大,當絲桿的應用出現以上的情況時,預壓等級可以選高一點,反之選低一點。選型

  6. Preloading grade, also known as preload, does not require specific preload force and preload method. We only need to select the preload grade according to the manufacturer's sample. The higher the preloading level, the tighter the nut and screw fit; On the contrary, the lower the level, the looser it is. The principles followed are: large diameter, double nuts, high precision, and large driving torque. When the above situations occur in the application of the screw, the preloading level can be selected higher, otherwise it can be selected lower. selection

  了解了以上絲桿主要的參數后,咱們就可以根據自己的要求進行選型了。

  After understanding the main parameters of the screw rod mentioned above, we can select the type according to our own requirements.

  步:根據上面“滾珠絲桿的分類”中提到的各種絲桿的應用場景,確定適用自己工況的絲桿種類;同時也可以確定絲桿的精度等級(一般為C7)和預壓等級;

  Step 1: Determine the type of screw that is suitable for your working conditions based on the application scenarios of various screw types mentioned in the "Classification of Ball Screw" section above; At the same time, the accuracy level (usually C7) and preloading level of the screw can also be determined;

  第二步:根據負載的大小,確定滾珠絲桿的軸徑;

  Step 2: Determine the shaft diameter of the ball screw based on the size of the load;

  第三步:根據負載需要的移動速度,確定導程;確定導程后,再根據推力和導程的關系式,確定驅動電機要提供的轉矩。具體如下:物體上下垂直運動,重量為60Kg,需要的移動速度為1m/s。

  Step 3: Determine the lead based on the required movement speed of the load; After determining the lead, determine the torque to be provided by the drive motor based on the relationship between thrust and lead. Specifically, the object moves vertically up and down, weighing 60Kg, and requires a moving speed of 1m/s.

  1)假如你選取了伺服電機為驅動,額定轉速為3000r/min=50r/s,根據公式:v=ri,確定導程為20;

  1) If you choose a servo motor as the drive and the rated speed is 3000r/min=50r/s, according to the formula: v=ri, determine the lead to be 20;

  2)然后再計算負載的大小:假設伺服電機的加減速時間設置為0.3s,那么加速度為3.3m/s?,負載F=600+60*3.3=798N(摩擦力這里忽略);

  2) Then calculate the size of the load: assuming the acceleration and deceleration time of the servo motor is set to 0.3s, then the acceleration is 3.3m/s? Load F=600+60 * 3.3=798N (friction force is ignored here);

  3)根據公式:F=(2πTn)/i,n取90%,計算得T≈2.82N·m,查詢1kW伺服電機是額定扭矩為3.18N·m,符合要求。以上,就基本確定了滾珠絲桿的型號,,再根據自己所需要使用到的行程,還有上面說到的絲桿安裝方式,確定絲桿的長度就可以了。

  3) According to the formula: F=(2 π Tn)/i, n is taken as 90%, and T ≈ 2.82N · m. The rated torque of the 1kW servo motor is 3.18N · m, which meets the requirements. Above, the model of the ball screw has been basically determined. Finally, based on the required stroke and the installation method of the screw mentioned above, the length of the screw can be determined.
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