PNEUMATIC IMPACT MECHANISM Russian patent published in 2024 - IPC E21B1/30 E21B4/14 E21C37/24 B25D9/14 

FIELD: construction; mining.

SUBSTANCE: invention relates to construction and mining, in particular to pneumatic impact devices. Pneumatic percussion mechanism comprises a cylindrical housing with outlet channels, an annular flange with a through central hole, a working tool with a shank, a stepped striker with rod and piston parts, installed in the central hole of the annular flange a rod with a piston part with a screw channel-slot, which is permanently located in the axial channel of the stepped striker, annular chamber of the pneumatic buffer, a sleeve of the cylindrical housing with an opening for the rod part of the striker, forming on the side of the annular chamber of the pneumatic buffer an annular isthmus limiting the value of displacement of the stepped striker, fixed relative to the cylindrical housing a cup with an air supply channel, an annular distribution chamber in the sleeve of the cylindrical housing, network air chamber on the side of annular flange with bypass channels constantly communicating with annular distribution chamber, idle stroke chamber on the side of shank of working tool held by spring relative to cylindrical housing. Outer side surface of the rod part of the stepped striker and the inner side surface of the sleeve of the cylindrical housing are made in the form of truncated cones with mating surfaces with minimum possible gap, which excludes mutual wedging. Annular accumulation chamber is formed between the cylindrical housing and the sleeve. In the wall of the sleeve there are through bypass channels with design areas of sections, constantly interconnecting the annular accumulation chamber and the annular distribution chamber between each other. Cylindrical housing on the side of the idle stroke chamber is equipped with an annular strap with a groove forming an annular accumulation chamber between the strap and the cylindrical housing. In the wall of the cylindrical housing there are radial bypass channels with design cross-section areas, constantly interconnecting the annular accumulation chamber and the idle stroke chamber.

EFFECT: reduction of air back pressure in the annular distribution chamber at the end of the idle stroke and increase in the air pressure in it during the working stroke of the stepped striker, as well as reduction of air counter-pressure before collision of striker with shank of working tool in idle stroke chamber and increase of air pressure in it at the beginning of idle stroke of striker immediately after collision, which provides increase of impact energy and frequency of impacts of pneumatic mechanism of percussion action.

1 cl, 1 dwg