C is hammer automatic restore structure which is characterized by small area, saving energy, convenient adjustment and dependable discharge dust and air lock.

C为吊锤自动复位机构，具有占地面积省、节能，卸灰调节方便，卸灰、锁气可靠之功能。

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D is CAM wheel pole driving, spring automatic restore structure, tight structure, reasonable design, stable driving, dust discharge and dependable air lock.

D为凸轮连杆传动，弹簧自动复位机构，结构紧凑、设计合理、运转平稳，卸灰、锁气可靠。

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