Patent ID: 8550180

Claim:
A breaking device comprising: a frame, a percussion device having a percussion element for generating compression stress pulses, a tool arranged on the extension of the percussion element and arranged to transmit the compression stress pulses to material to be broken as stress waves, and at least one bearing bushing arranged in a bearing space around the tool, which bearing bushing is of bearing material, whereby it is arranged to form a slide bearing for the tool moved in the axial direction, wherein an initial clearance space in the radial direction is arranged between the outermost diameter of the bearing bushing and the diameter of the bearing space, wherein the bearing bushing is of permanently deformable bearing material such that when deformed the material is permanently deformed, wherein the bearing bushing is prevented in the axial direction from getting out of the bearing space after the mounting, and wherein the bearing bushing is locked in place in the bearing space in both the axial and radial directions during the use of the breaking device when the stress waves in the tool and the movement in the direction of the perpendicular of the tool surface due to the waves have caused the bearing bushing to be enlarged in the direction of the periphery and radially deformed against the bearing space to lock the bushing immovably axially and radially in the bearing space.