The roto-packer, which designed and manufactured by Hubei Cement Machinery Plant, is on usher in German HAVER & BOECKER Corporation appropriation technology foundation, through unceasingly digests, absorption and innovation to develop and manufacture this new series type cement packer. This series product, comparing with the original product, has the most prominent merit is: The high production process automaticity; precise and stable weighing; safe and reliable movement; extremely low product breakdowns; few maintain workload, compact system structure, good sealing property and few work dust. This series packer passes through the long-term stable movement inspection and indicates that its main performance already achieves international standard. According to the weighing way, this packer divides into mechanical type and electronic type. The electronic weigher packer uses the highly reliable microcomputer controller or imported programmable logic controller (PLC) to carry on the process control.The maximal characteristic of microcomputer electronic weigher is as follows: the touch keyboard can easy realize the dialogue between the human being and the machine. the big screen liquid crystal display can display the working information of the packer. the function of working parameter adjustment, trouble diagnosis and printing can meet the customer's requirements. The characteristic of the PLC electronic weigher is simple structure, high reliable movement, few maintain workload and has the function of automatic adjustment for bag weight.