Breaking hammer and method of supporting percussion piston

A hydraulic breaking hammer, comprising:

• a percussion device including a frame and a piston arranged inside the frame, the percussion device being configured to perform a working cycle including reciprocating longitudinal movement of the piston in an impact direction and a return direction due to pressure of hydraulic fluid fed to first and second working pressure spaces of the percussion device;
• at least one control device is arranged for controlling feeding and discharging of the hydraulic fluid of at least one of the first and second pressure spaces for executing the working cycle;
• a working collar of the piston located between the first and second working pressure spaces and wherein an outer surface of the working collar is sealed to surrounding structures so that the first and second working pressure spaces are hydraulically separated;
• and
• a first piston bearing and a second piston bearing located at an axial distance from each other, wherein the first and second piston bearings are configured to provide support for opposite first and second end portions of the piston, whereby the first working pressure space, the working collar and the second working pressure space are all located between the first and second piston bearings, the second piston bearing being a separate sleeve-like second piston bearing element mountable to the frame in one piece, wherein a radial clearance is disposed between the outer surface of working collar and the second piston bearing element and at least one separate collar sealing element being arranged to seal the radial clearance, and wherein the second piston bearing element includes at least one first sealing housing for the at least one separate collar sealing element.