specifically as an excavator a hydraulic tool 15 is attached by way of an extension arm or boom 31 the tool 15 is equipped with a lubrication apparatus 32 according to the invention the hydraulic hammer chisel is exposed to high mechanical loads and must be supplied with heat resistant special lubricant the following exemplary embodiments of the lubrication apparatus according to the invention illustrated as specific structures are also designed to be used with special lubricants having a large component of solid materials e g copper chisel paste or to be used with ep2 fat the lubrication apparatus 32 in accordance with the invention is installed in the hydraulic tool 15 or its carrier device itself which eliminates long lubricant conduits to the construction machine furthermore owing to the direct installation of the lubrication apparatus 32 the chisel and lubrication apparatus can be attached as a complete unit to any excavator because there is no need for installation in the excavator the lubrication apparatus according to the invention is not negatively affected by the considerable vibrations and or accelerations of the hydraulic hammer the lubrication apparatus according to the invention must merely be connected to the hydraulic fluid system of the construction machine 30 by way of a high pressure tube in order to supply the lubrication apparatus 32 with energy a lubricant pump 12 of the lubrication apparatus 32 is driven by a hydromotor 14 which is connected to the hydraulic circulation of the construction machine 30 for example following actuation of the foot switch for the hydraulic tool 15 which is situated in the driver 39 s cabin the lubrication.