Self-loading concrete mixer has a long history.In the early 20th century,drum

concrete mixer by steam engine appeared.After 1950s,double cone concrete mixer of the

reversal discharge type and tilting discharge type,crack drum concrete mixer and etc.

are appeared and have good development.There is an arranged radially blade on the

wall of self-loading concrete mixer.When working,agitator drum turns around

horizontal axis,charging materials will be tipped to the right height,then falling by

self-weight.Then go around and around so that mix concrete equality.Self-loading

concrete mixer has simple structure,mainly mix plastic materials.
Forced type concrete mixer After early 1950s,forced type concrete mixer has a

promptly development and spread.At first appeared vertical shaft forced concrete

mixer.This mixer has two types turboprop and planetary.After 1970s,together with

application of light aggregate appeared circular slot forced shaft concrete

mixer.This machine has single shaft and twin shaft two types.And this machine has

characteristics self-loading and forced.It has many characteristics such as low speed

blade,good abrasion resistance,low energy consumption,developing faster and etc.On

the shaft arm installed blade on the drum wall of forced type concrete

mixer.Materials which is added to the mixing drum, under the powerful stirring for

mixing blades, will form. cross-logistics.This concrete mixer type has stronger

forced than self-loading mixer.Forced type concrete mixer mainly used in dry and hard

concrete.