Hydraulic impact tool with a protective disc

Abstract

Hydraulic impulse tool (100), comprising at least a motor, an output shaft (10) and a hydraulic impulse unit (20) with an inertial drive element (21) which is drivenly connected to the motor and rotatable about a rotary axis (AA), a hydraulic fluid chamber (22) enclosed in the inertial drive element and an impulse generation mechanism which is arranged to intermittently transfer kinetic energy to the output shaft, wherein the impulse tool further comprises a compressible element (50) which is arranged in an insert space (23) which is in fluid communication with the hydraulic fluid chamber, wherein the compressible element (50) is configured to compensate for increases and decreases in the fluid volume in the hydraulic fluid chamber;and a protective disc (60) arranged between the hydraulic fluid chamber and the compressible element within the operating space, the protective disc comprising a flow constriction (P1) designed to direct the fluid flow through the protective disc during an increase in fluid volume, thereby damping pressure fluctuations in the hydraulic fluid chamber acting on the compressible element.