Abstract: A single - stroke pneumatic apparatus comprises a hollow cylindrical frame 1) in which is mounted for reciprocating back and forth a striker (2) forming in the frame (1) front and rear chambers (3 and 4), the front chamber (3) has its own inlet and outlet ports (5 and 6) and the rear chamber (4) has its own ports (7 and 8). A directional flow control sleeve (10) fitted outside the frame (1) is arranged to uncover and cover the inlet and outlet ports (5, 6, 7, 8). The directional flow control sleeve (10) is provided with front and rear longitudinal internal passages (11 and 12) and front and rear radial holes (13 and 14).

Abstract: A single-stroke pneumatic apparatus incorporates a hollow cylindrical frame 1) with inlet and outlet ports (2,3). A handgrip (4) containing a directional flow control (5) is attached to the upper end of the frame. A striker (6) is provided in the bore of the frame (1) with provision for reciprocating back and forth so as to divide this bore into a forward-stroke chamber (8) a back-stroke chamber (7). A tool (9) is supported in the lower end of the frame (1). A shell (10) with holes (11) surrounds the frame (1) from the outside, forming a muffling chamber (12) therewith, within a full length of the stroke of the striker (6). Additional outlet ports (15) are provided in the lower end of the frame (1) which communicate the back-stroke chamber (8) with the muffling chamber (12) located wherein is a filter (6) overlapping the holes (11) in the shell (10).

Abstract: A single-blow pneumatic percussive tool comprises a hollow cylindrical casing (1) accommodating a reciprocatable hammer piston (2) which divides the interior space of the casing (1) into an upper and a lower chambers (3, 4). A spring-biased valve (5) is mounted on the side of the lower chamber (4) and a working member (6) is secured to the valve (5). An air distribution device (7) is mounted on the side of the upper chamber (3) and has passages (8, 9, 10) and a control lever (11). The hammer piston (2) has an axial passage (13) in which a tube (14) is mounted which has a shoulder (15) on the outer surface and a continuous inner partition wall (16). The tube (14) has upper and lower ports (17, 18) disposed on either side of the partition wall (16). An air distribution sleeve (19) biassed by spring on the side of the air distribution device (7) is mounted on the tube (14) and has an inner recess (21).