DEVICE FOR FEEDING WATER UNDER PRESSURE TO THE NOZZLES AT THE PERIPHERY OF A COAL CUTTING TOOL

摘要

1. A device for feeding water under pressure to nozzles on the periphery of a coal cutting tool which is fitted with bits (1) whose stems (7) are mounted so as to be axially displaceable in bit holders (2), the water being discharged from the nozzles (21) in dependence upon the displacement movement of the bit (1) and the volume of water to be sprayed out being able to be fed to a chamber in the bit holder (2) via a non-return valve (12), in which chamber the bit stem (7) or a part connected thereto is submerged, characterised in that the non-return valve (12) and the valve spring (13) are arranged in a casing (11), which is overlapped by a hollow cylindrical part (10) of the bit stem (7) or of a part connected thereto in a force-locking manner when the bit (1) is displaced inwardly, the liquid between the hollow cylindrical part (10) of the bit stem (7) and the casing (11) flowing out partially throttled during the stroke of the bit.