TWO-PISTON AIR HAMMER Russian patent published in 2017 - IPC E21B4/14 E21B1/24 E21B1/38 E21C37/24 B25D9/14 

FIELD: machine engineering.

SUBSTANCE: device includes a housing with two coaxially located cylindrical cavities separated by a partition with an opening, two pistons located within the cylindrical cavities having cavities of driving and idle strokes, a shank coaxially arranged with the pistons, an air distribution unit with air supply and air discharge channels of equal diametre and a working slide valve in the form of a hollow cylinder, installed in a cylindrical cavity, with the formation of chambers. One of the pistons is made hollow with a hollow rod, and the second piston is made solid with a solid rod installed in the cavity of the other piston and the opening of the partition between the cylinders. The second piston is equipped with a command slide valve of cylindrical shape installed coaxially to the rod on the opposite side of the piston, wherein an axial channel, an exhaust annular groove, an air supply groove with openings communicating with the chambers of the working slide valve cavity and with the atmosphere by the channels are formed. The working slide valve is mounted with the possibility of axial movement along the command slide valve and is equipped with a supply and discharge annular grooves. The supply groove is connected with an axial air supply channel and cylindrical cavities of the pistons by the channels, and the discharge groove is connected with the atmosphere by air discharge channels and channels with cylindrical piston cavities. The ducts are located at a distance from each other, equal to three channel diametres. The width of the grooves is equal to the diametre of the channel. The distance between the channels in the working slide valve zone is equal to the diametre of the channel. The stroke of the working slide valve is equal to two channel diametres.

EFFECT: increased operational characteristics and performance reliability.

2 cl, 4 dwg