PNEUMATIC HAMMER WITH THROTTLE AIR CONTROL VALVE Russian patent published in 2012 - IPC B25D9/00 

FIELD: process engineering.

SUBSTANCE: invention relates to mining, particularly, to impact devices. Hammer comprises network chamber, handle with compressed air feed switch to force air into network chamber with inlet channel. Hollow cylinder houses hammer with central channel to divide cylinder inside into idle and working stroke chambers. Central tube passes through hammer central channel to communicate network chamber with idle stroke chamber. Fixed cover has central through opening to receive tube. Restricting channel open into working stroke chamber represents annular channel to vary cross-section shape and is made up of tube lateral surfaces and central through opening to communicate network chamber with working stroke chamber, and annular accumulation chamber communicated with the latter via bypass channel. Radial outlet channel is made in cylinder sidewall. Extra tube is arranged in central tube and aligned therewith. Said extra tube is made from elastic material and has closed end on idle stroke chamber side. Extra tube is fixed relative to central tube to communicate with idle stroke chamber via network chamber annular clearance. Central tube has radial slor-like opening extending to tube end on working tool shank.

EFFECT: stable starting.

2 dwg