A pneumatic hammer comprising:
- a handle having a top;
- a body transversally connected to the top of the handle, communicating with the handle, and having
- a closed end;
- an open end opposite to the closed end of the body;
- an external surface;
- and
- a chamber formed in the body between the closed end and the open end of the body and communicating with the open end of the body;
- a valve seat mounted in the chamber of the body adjacent to the closed end of the body and having
- a rear valve having
- a rear side;
- a front side;
- an external surface;
- a center;
- an inlet recess formed in the front side of the rear valve at the center of the rear valve opposite to the closed end of the body;
- an annular groove annularly formed in the front side of the rear valve around the inlet recess at a spaced interval from the inlet recess;
- an inlet passage radially formed through the external surface of the rear valve and communicating with the inlet recess;
- an exhaust port axially formed in the front side of the rear valve and communicating with the inlet recess;
- two inlet channels radially formed through the external surface of the rear valve;
- and
- two exhaust channels axially formed in a front side of the annular groove, and respectively communicating with the inlet channels, and each one of the exhaust channels and a corresponding inlet channel forming an L-shaped air channel to communicate with the annular groove;
- a front valve connected to the rear valve;
- and
- a valve plate mounted between the rear valve and the front valve;
- a cylinder device mounted in the chamber of the body via the open end of the body, abutting against the valve seat, and having
- a cylinder barrel mounted in the chamber via the open end of the body, abutting against the valve seat, and having a cylinder chamber axially formed in the cylinder barrel and communicating with the valve seat;
- and
- a hammer axially and movably mounted in the cylinder chamber of the cylinder barrel;
- an assembling device connected to the cylinder barrel of the cylinder device opposite to the valve seat, communicating with the cylinder barrel, and having
- a mounting jacket being hollow and having
- a rear end;
- a front end;
- an internal surface;
- an assembling chamber formed in the mounting jacket adjacent to the rear end of the mounting jacket and communicating with the cylinder barrel;
- an engaging recess annularly formed in the internal surface of the mounting jacket adjacent to the assembling chamber and opposite to the rear end of the mounting jacket;
- and
- a mounting recess being conical, formed in the mounting jacket adjacent to the front end of the mounting jacket, communicating with the assembling chamber, and having
- a rear flange formed in the internal surface of the mounting jacket adjacent to the assembling chamber;
- and
- a front flange being tapered and formed in the internal surface of the mounting jacket adjacent to the front end of the mounting jacket;
- an engaging element being hollow, mounted in the mounting jacket via the assembling chamber, extending out of the front end of the mounting jacket via the mounting recess, and having
- a front end extending out of the front end of the mounting jacket via the mounting recess;
- a rear end;
- an external surface;
- a communicating hole axially formed through the front end and the rear end of the engaging element and communicating with the assembling chamber of the mounting jacket;
- and
- multiple assembling holes radially formed through the external surface of the engaging element at spaced intervals communicating with the communicating hole and the mounting recess of the mounting jacket, and each one of the assembling holes having two sectional inner diameters, one of the sectional inner diameters disposed adjacent to the communicating hole, and the other one of the sectional inner diameters disposed adjacent to the mounting recess and being larger than the sectional inner diameter that is disposed adjacent to the communicating hole;
- multiple positioning elements respectively held in the assembling holes of the engaging element without falling in the communicating hole by the two sectional inner diameters of each one of the assembling holes, partially extending into the mounting recess of the mounting jacket, and abutting against the front flange of the mounting recess of the mounting jacket;
- a spring mounted in the assembling chamber of the mounting jacket and abutting against the rear end of the engaging element;
- and
- an engaging ring disposed in the engaging recess of the mounting jacket and abutting against the spring to hold the spring in the mounting jacket by the engaging element and the engaging ring;
- and
- a chisel detachably connected to the assembling device and inserted into the cylinder chamber of the cylinder barrel of the cylinder device.