The material handling conveyor transports material continuous on a fixed route.It also can be called continuous handling conveyor. Conveyor are available for horizontal ,inclined and vertical conveying .And also it can be composed of space transmission lines.  Usually the transmission line is fixed .Conveyors have large capacity ,long conveying distance ,available for finishing much work during conveying process ,wide application .
  China ancient high drum cart and the roller of water are  in an early form for modern bucket conveyor and scraper conveyor.In the middle of 17^th Century , aerialtramway had been applied in conveying bulk solids .In the middle of 19^th ,all kinds of modern structure conveyors came into being in series .

In 1868 ,the belt conveyor came out in United Kingdom .In 1887,the screw conveyor/spiral conveyor came out in United State .In 1905 ,the steel belt conveyor came out in Switzerland .In 1906 ,the Inertial conveyor came out in United Kingdom and Germany .

From then on ,conveyors were continuous improved by the progress in mechanical manufacturing ,electrical motor ,chemical and metallurgical industry .
 Classification and Structure   Conveyors are usually classified according to whether there is a traction or not .
  ①The conveyor with traction usually includes traction equipment ,bearing carrier ,drive unit ,stretching device ,redirection device ,support assembly ,etc . The traction equipment is used for traction transmission ,taking conveyor belt ,drag chain or hoisting cable .The bearing carrier is used for bearing and putting materials ,matching with hopper ,bracket or hanger and stairs for carrying person .The drive unit set he motion to the conveyor .Usually it is consisted of electrical motor ,reducer and decelerator ,etc .The stretching device usually has auger type and lever with weight type ,which make traction equipment keep a certain tension and sag ,so as to guarantee conveyors work smoothly . The support assembly is used for supporting traction equipment or bearing parts  ,and it maybe take carrier roller ,idler wheel ,etc. The feature of traction conveyor is: the conveyed material are put into a bearing carrier with traction equipment ,or install on the traction(such as conveyor belt ) .Traction equipments  beyond  all  rollers or  sprocket wheels  end to end ,to form including conveying materials called load branches and  no conveying materials called unload braches’ closed circuit ,making use of traction equipment continuous work to convey materials , There are various of conveyors ,mainly for belt conveyor ,slat conveyor ,car type conveyor , escalator, moving pavement ,scraper conveyor ,enmasse conveyor ,bucket conveyor ,bucket elevator ,trolley conveyor and overhead cableway ,etc .(See Figure)
  ②No traction equipment’s conveyors’ structures are different .So are the work unit for conveying materials . Their Structures are : taking use of work unit’s rotation or alternating motion, ,or using media flow in the pipe ,so as to move materials

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Roller Conveyors’ work unit is a series of rollers ,as roller rotation to convey materials Screw Conveyor’s work component is screw .Screw rotaries in the trough to push materials along the trough .Vibration Conveyor’s work component is trough .The trough is for reciprocating to transport materials . Pneumatic conveying equipment, hydraulic transmission device and the container-type devices to piped gas or liquid medium in the pipeline for the transportation of materials.

Most conveyors are driven by electric drive , Internal combustion engine , Pneumatic driven or hydraulic driven .