The concrete mixer truck is composed of truck chassis and special equipment for concrete mixing and transportation. The chassis of concrete mixer truck produced in China mostly adopts class II general chassis provided by vehicle manufacturers. Its special mechanism mainly includes power take-off, front and rear support of mixing drum, reducer, hydraulic system, mixing drum, control mechanism, cleaning system, etc. Its working principle: the power of the automobile chassis is taken out by the power take-off device, and the variable pump of the hydraulic system is driven. The mechanical energy is converted into hydraulic energy and transmitted to the quantitative motor. The motor drives the reducer, and the reducer drives the mixing device to mix the concrete.

1．1取力装置

1.1 power take-off device

国产混凝土搅拌运输车采用主车发动机取力方式。取力装置的作用是通过操纵取力开关将发动机动力取出，经液压系统驱动搅拌筒，搅抖筒在进料和运输过程中正向旋转，以利于进料和对混凝土进行搅拌，在出料时反向旋转，在工作终结后切断与发动机的动力联接。

The main engine power take-off mode is adopted for domestic concrete mixer truck. The function of the power take-off device is to take out the power of the engine by operating the power take-off switch, and drive the mixing drum through the hydraulic system. The stirring drum rotates forward in the process of feeding and transportation to facilitate the feeding and mixing of concrete. It rotates reversely when discharging, and cuts off the power connection with the engine after the end of the work.

1．2液压系统

1.2 hydraulic system

将经取力器取出的发动机动力，转化为液压能(排量和压力)，再经马达输出为机械能(转速和扭矩)，为搅拌筒转动提供动力。\

The engine power taken out by the power take-off device is converted into hydraulic energy (displacement and pressure), and then the motor outputs mechanical energy (speed and torque) to provide power for the rotation of the mixing drum.

1．3减速机

1.3 reducer

将液压系统中马达输出的转速减速后，传给搅拌筒。

After decelerating the speed of the motor output in the hydraulic system, it is transmitted to the mixing drum.

1．4操纵机构

1.4 control mechanism

a．控制搅拌筒旋转方向，使之在进料和运输过程中正向旋转，出料时反向旋转。

a. Control the rotation direction of the mixing drum to make it rotate forward in the process of feeding and transportation, and reverse rotation when discharging.

b．控制搅拌筒的转速

b. Control the speed of mixing drum

1．5搅拌装置

1.5 mixing device

它主要由搅拌筒及其辅助支撑部件组成。搅拌筒是混凝土的装载容器，它是由耐磨薄钢板制成，为了能够自动装、卸混凝土，其内壁焊有特殊形状的螺旋叶片。转动时混凝土沿叶片的螺旋方向运动，在不断的提升和翻动过程中受到混合和搅拌。在进料及运输过程中，搅拌筒正转，混凝土沿叶片向里运动，出料时，搅拌筒反转，混凝土沿着叶片向外卸出。搅拌筒的转动则是靠液压驱动装置来保证。装载量为3～6立方的混凝土搅拌运输车一般采用由汽车发动机通过动力输出轴带动液压泵，再由高压油推动液压马达驱动搅拌筒，装载量为9～12立方的则由车载辅助柴油机带动液压泵驱动液压马达。叶片是搅拌装置中的主要部件，损坏或严重磨损会导致混凝土搅拌不均匀。另外，叶片的角度如果设计不合理，还会使混凝土出现离析。

It is mainly composed of mixing drum and its auxiliary supporting parts. The mixing drum is a concrete loading container, which is made of high-quality wear-resistant thin steel plate. In order to automatically load and unload concrete, its inner wall is welded with spiral blades of special shape. When rotating, the concrete moves along the spiral direction of the blade, and is mixed and mixed in the process of continuous lifting and turning. In the process of feeding and transportation, the mixing drum rotates forward, and the concrete moves inward along the blade. When discharging, the mixing drum reverses and the concrete is discharged outward along the blade. The rotation of the mixing drum is ensured by the hydraulic driving device. The concrete mixer truck with a loading capacity of 3-6 cubic meters generally adopts the hydraulic pump driven by the automobile engine through the power output shaft, and then the mixing drum is driven by the hydraulic motor driven by the high-pressure oil. For the concrete mixer truck with the loading capacity of 9-12 cubic meters, the hydraulic pump driven by the auxiliary diesel engine is used to drive the hydraulic motor. Blade is the main part of the mixing device, damage or serious wear will lead to uneven mixing of concrete. In addition, if the angle of blade is not reasonable, it will cause concrete segregation.