the boom, in particular for a streckenauffahrmaschine in untertaegigen underground

摘要

1396905 Mounting for rock working tools DOBSON PARK INDUSTRIES Ltd 6 Aug 1973 [12 Aug 1972] 37681/72 Heading B3C [Also in Division E1] A tool mounting arrangement comprises a linkage A, B, C, D of variable configuration pivotally attached to a support 20 and to a tool or to a carrier 26 for a tool 27, and means 24 for pivoting the linkage relative to the support, the linkage changing its configuration during such pivoting so that the tool remains directed towards the same aim point while its angle of attack is varied. The aim point of the tool may be varied by means of a ram 28, 30 constituting the arm C of the linkage, and may be slewed on its carrier 26 by means of a ram 33. The support 20 is at the end of a beam 13 movable horizontally on a carriage (10) of a mining machine having floor- and roof-engaging jacks (11), (12), Fig. 1A (not shown). The tool may be a percussive rock-breaking tool, for example as disclosed in Specification 1,356,022.