Aiming at the problem that the concentrated air flow cannot be adjusted during the cluster DTH hammer operating,an air flow adjustment mechanism was designed.The cluster DTH hammer air flow adjustment mechanism was driven by multiple cylinders.In order to ensure that the air flow can be adjusted and distributed evenly,it is required to maintain synchronization when the driving cylinder is moving.A double synchronous valve was used to control the three-cylinder synchronization;the mechanical structure and working principle of the synchronous valve were analyzed,and the mathematical model of the synchronous valve was established;the synchronization characteristics of the dual-synchronous valve control and adjustment mechanism under different loads were verified by test.The results show that the three-cylinder synchronization characteristics are better under uniform load conditions,and the three-cylinder synchronization characteristics become worse as the load eccentric load increases.