Screw is a commonly used transmission component in engineering machinery and precision machinery. The main structure of a screw is composed of a screw and a nut, and its main function is to convert rotational motion into linear motion or torque into axial repeated force. The principle is that when the lead screw is used as the driving body, the nut converts into linear motion according to the corresponding specifications of the lead with the rotation angle of the lead screw. The passive workpiece can be connected through a nut seat and nut to achieve corresponding linear motion. Roller screw has the characteristics of high transmission efficiency and precision, and has basically replaced traditional trapezoidal screw in most scenarios. The commonly used thread screws can be divided into triangular thread screws, trapezoidal thread screws, ball screws, and planetary roller screws.

（1） 三角螺紋絲杠：三角牙絲杠其牙型類似于三角形頂部為尖狀，是各類簡(jiǎn)易螺 絲常用的牙型，其加工便當(dāng)、制作簡(jiǎn)略，市場(chǎng)上有較多標(biāo)準(zhǔn)件出售。 （2） 梯形螺紋絲杠：梯形螺紋絲杠的牙型為等腰梯形，上窄下寬。加工相對(duì)簡(jiǎn)略， 可以依據(jù)牙的深淺來(lái)調(diào)理螺母和絲桿的松緊度。表里螺紋以錐面貼緊不易松 動(dòng)，工藝較好，牙根強(qiáng)度高，對(duì)中性好。梯形絲桿的傳動(dòng)效率大約為26-46%。

(1) Triangle thread screw: Triangle thread screw has a tooth shape similar to the pointed top of a triangle, which is commonly used for various simple screws. Its processing is convenient and its production is simple, and there are many standard parts available for sale in the market. (2) Trapezoidal thread screw: The tooth shape of the trapezoidal thread screw is an isosceles trapezoid, with a narrow top and a wide bottom. The processing is relatively simple, and the tightness of the nut and screw can be adjusted based on the depth of the teeth. The thread inside the watch is tightly attached with a conical surface, which is not easy to loosen. The process is good, the root strength is high, and it is good for neutrality. The transmission efficiency of the trapezoidal screw is approximately 26-46%.

（3） 滾珠螺紋絲杠：其絲桿和螺母之間選用滾珠翻滾的方式來(lái)進(jìn)行傳動(dòng)，可通過(guò) 替換滾珠的方式來(lái)絲杠和螺母之間的空地。故傳動(dòng)功率高，精度高，靜 音作用好。

(3) Ball screw: The ball rolling method is used for transmission between the screw and nut, and the vacant space between the screw and nut can be eliminated by replacing the ball. Therefore, the transmission power is high, the accuracy is high, and the mute effect is good.

現(xiàn)已廣泛的應(yīng)用于各種自動(dòng)化設(shè)備，機(jī)床等。一般環(huán)境下已大部 分替代了梯形絲杠，其傳動(dòng)效率約為90-96%。

It has been widely used in various automation equipment, machine tools, etc. In general, trapezoidal screws have been mostly replaced, with a transmission efficiency of approximately 90-96%.

（4） 行星滾柱絲杠：標(biāo)準(zhǔn)行星滾柱絲杠主要由絲杠、滾柱、螺母、直齒、內(nèi)齒圈、 滾柱保持架和彈簧擋圈等組成，其綜合了行星齒輪傳動(dòng)、諧波齒輪傳動(dòng)、滾 珠絲桿、滾針軸承等機(jī)構(gòu)的優(yōu)點(diǎn)。通過(guò)在主絲杠周圍布置若干行星螺紋滾柱, 大幅增加絲杠傳動(dòng)過(guò)程的接觸面和受力面,從而具備了“高承載、率、高 精度、高可靠性”等優(yōu)點(diǎn)。在絲杠轉(zhuǎn)速、接觸角與螺旋升角較為理想的狀態(tài) 下，行星滾柱絲杠傳動(dòng)效率可達(dá)到90%以上。

(4) Planetary roller screw: The standard planetary roller screw is mainly composed of screw, roller, nut, straight tooth, inner gear ring, roller cage, and spring retainer, which combines the advantages of planetary gear transmission, harmonic gear transmission, ball screw, needle roller bearing and other mechanisms. By arranging several planetary thread rollers around the main lead screw, the contact surface and stress surface of the lead screw transmission process are greatly increased, thus possessing the advantages of "high load-bearing, high efficiency, high precision, and high reliability". Under ideal conditions of screw speed, contact angle, and helix angle, the planetary roller screw transmission efficiency can reach over 90%.

其中三角螺紋絲杠與梯形絲杠生產(chǎn)技術(shù)相對(duì)較為簡(jiǎn)單，已基本實(shí)現(xiàn)完全國(guó)產(chǎn)化。滾 珠絲杠發(fā)展起步相對(duì)較早，低端滾珠絲杠國(guó)產(chǎn)化率已達(dá)到相對(duì)較高水平。但目前國(guó) 內(nèi)在中滾珠絲杠及行星滾柱絲杠的國(guó)產(chǎn)化率相對(duì)較低，未來(lái)發(fā)展空間較大。

The production technology of triangular thread screw and trapezoidal screw is relatively simple and has basically achieved complete localization. The development of ball screws started relatively early, and the localization rate of low-end ball screws has reached a relatively high level. However, at present, the localization rate of high-end ball screws and planetary roller screws in China is relatively low, and there is greater room for future development.

直線導(dǎo)軌結(jié)構(gòu)簡(jiǎn)單穩(wěn)定，大量運(yùn)用于機(jī)械加工過(guò)程中。直線導(dǎo)軌在機(jī)械加工中比較 常用，其由鋼珠在滑塊跟導(dǎo)軌之間無(wú)限滾動(dòng)循環(huán)， 從而使負(fù)載平臺(tái)沿著導(dǎo)軌輕易的 高精度線性運(yùn)動(dòng)。依按摩擦性質(zhì)而定，直線運(yùn)動(dòng)導(dǎo)軌可以分為滑動(dòng)摩擦導(dǎo)軌、滾動(dòng) 摩擦導(dǎo)軌、彈性摩擦導(dǎo)軌、流體摩擦導(dǎo)軌等種類。直線導(dǎo)軌下游應(yīng)用廣泛，主要包括 數(shù)控機(jī)床、醫(yī)療器械、自動(dòng)化生產(chǎn)線等領(lǐng)域。

The linear guide rail structure is simple and stable, and is widely used in mechanical processing. Linear guide rails are commonly used in mechanical processing, where steel balls infinitely roll and circulate between the slider and the guide rail, allowing the load platform to easily move in high-precision linear motion along the guide rail. According to the friction properties, linear motion guides can be divided into sliding friction guides, rolling friction guides, elastic friction guides, fluid friction guides, and other types. Linear guide rails are widely used downstream, mainly in fields such as CNC machine tools, medical devices, and automated production lines.