The self dropping mixer has a long history. As early as the beginning of the 20th century, the drum concrete mixer driven by the steam engine has begun to appear. After 50's, the double cone mixer of reverse discharge type and tipping discharge type and split drum mixer came out and developed one after another. The inner wall of the mixing drum of the self dropping concrete mixer is provided with the mixing blades arranged radially. During the operation, the mixing drum rotates around its horizontal axis, and the materials in the mixing drum are added. After being lifted to a certain height by the blades, they fall by the self weight, so that they move around again and again to achieve the effect of uniform mixing. The structure of self dropping concrete mixer is simple, and it is mainly used to mix plastic concrete.

強制式攪拌機從20世紀50年代初興起后，得到了迅速的發(fā)展和推廣。先出現(xiàn)的是圓盤立軸式強制自上料水泥攪拌車這種攪拌機分為渦槳式和行星式兩種。19世紀70年代后，隨著輕骨料的應用，出現(xiàn)了圓槽臥軸式強制攪拌機，它又分單臥軸式和雙臥軸式兩種，兼有自落和強制兩種攪拌的特點。其攪拌葉片的線速度小，耐磨性好和耗能少，發(fā)展較快。

Since the rise of forced mixer in the early 1950s, it has been developed and popularized rapidly. The first appeared is the disc vertical shaft type forced concrete mixer, which is divided into two types: the turboprop type and the planetary type. After 1870's, with the application of lightweight aggregate, the forced mixer with horizontal shaft and round trough appeared. It is divided into single horizontal shaft type and double horizontal shaft type, and has the characteristics of self dropping and forced mixing. It has the advantages of low linear speed, good wear resistance, low energy consumption and rapid development.

強制式自上料水泥攪拌車拌筒內(nèi)的轉(zhuǎn)軸臂架上裝有攪拌葉片，加入拌筒內(nèi)的物料，在攪拌葉片的強力攪動下，形成交叉的物流。這種攪拌方式遠比自落攪拌方式作用強烈，主要適于攪拌干硬性混凝土。連續(xù)式自上料水泥攪拌車裝有螺旋狀攪拌葉片，各種材料分別按配合比經(jīng)連續(xù)稱量后送入攪拌機內(nèi)，攪拌好的混凝土從卸料端連續(xù)向外卸出。這種攪拌機的攪拌時間短，生產(chǎn)率高、其發(fā)展引人注目。

A mixing blade is installed on the rotating arm of the mixing drum of the forced concrete mixer, and the materials in the mixing drum are added. Under the strong agitation of the mixing blade, the cross logistics is formed. This kind of mixing method is far stronger than the self dropping mixing method, and is mainly suitable for mixing dry and hard concrete. The continuous concrete mixer is equipped with spiral mixing blades. Various materials are weighed continuously according to the mix proportion and then sent into the mixer. The mixed concrete is discharged from the discharge end continuously. The mixer has the advantages of short mixing time, high productivity and remarkable development.

隨著混凝土材料和施工工藝的發(fā)展、又相繼出現(xiàn)了許多新型結(jié)構(gòu)的自上料水泥攪拌車,如蒸汽加熱式攪拌機,超臨界轉(zhuǎn)速攪拌機，聲波攪拌機，無攪拌葉片的搖擺盤式攪拌機和二次攪拌的自上料水泥攪拌車等。

With the development of concrete materials and construction technology, many new types of concrete mixers have emerged in succession, such as steam heated mixers, supercritical speed mixers, acoustic mixers, swaying plate mixers without mixing blades and concrete mixers with secondary mixing, etc.

連續(xù)式自上料水泥攪拌車裝有螺旋狀攪拌葉片，各種材料分別按配合比經(jīng)連續(xù)稱量后送入攪拌機內(nèi)，攪拌好的混凝土從卸料端連續(xù)向外卸出。這種攪拌機的攪拌時間短，生產(chǎn)率高、其發(fā)展引人注目。隨著混凝土材料和施工工藝的發(fā)展、又相繼出現(xiàn)了許多新型結(jié)構(gòu)的自上料水泥攪拌車,如蒸汽加熱式攪拌機,超臨界轉(zhuǎn)速攪拌機，聲波攪拌機，無攪拌葉片的搖擺盤式攪拌機和二次攪拌的自上料水泥攪拌車等。

The continuous concrete mixer is equipped with spiral mixing blades. Various materials are weighed continuously according to the mix proportion and then sent into the mixer. The mixed concrete is discharged from the discharge end continuously. The mixer has the advantages of short mixing time, high productivity and remarkable development. With the development of concrete materials and construction technology, many new types of concrete mixers have emerged in succession, such as steam heated mixers, supercritical speed mixers, acoustic mixers, swaying plate mixers without mixing blades and concrete mixers with secondary mixing, etc.