PNEUMATIC IMPACT MECHANISM Russian patent published in 2015 - IPC E21B4/14 

FIELD: construction.

SUBSTANCE: pneumatic impact mechanism includes a body, in which an adapter is installed with a manifold channel and a circular groove, as well as a piston with a central hole, forming chambers of operational and idle stroke with the cylindrical surface of the body, an elastic valve in the form of a torus, installed in the specified circular groove of the adapter with preliminary tightening and possibility to periodically form a contact edge of the torus and the cylindrical surface of the body of the feed channel for the operational stroke chamber, a spindle valve with central, radial and external channels for supply of coolant into operational and idle stroke chambers, fixed in the adapter and installed in the central hole of the piston, and a drilling tool. The torus of the elastic valve along the contact edge has cylindrical surface, and external channels of the spindle valve are shifted from the torus of the adapter to form a sealing belt made as capable of insertion into a central hole of the piston to create at the end of the idle stroke an air buffer cushion communicated with the manifold channel of the adapter via the specified feed channel.

EFFECT: improved conditions of operation of an elastic valve in the form of a torus by increasing resulting forces during opening and closure of a feed valve.

2 cl, 1 dwg