HOLDER FOR A PICK, AND THE COMBINATION OF A PICK AND HOLDER

摘要

ABSTRACTA holder for a pick and the combinationof a pick and holder.The pick 1 has a shank 4 received in a socket6 of a holder 2. The holder 2 carries in itssocket 6 a tubular spigot 13 which mates in sealedmanner with a coupling socket 15 in the pick shankto provide communication for water flow from asupply passage 16a through the pick 1 to outletports 12. A shoulder 8 on the spigot 13 abutsa sealing ring 18 in the coupling socket 15 toretain the pick in the holder and permit relativelongitudinal displacement therebetween.Carried by the tubular spigot 13 is a valvehaving an actuating rod 22 which extends throughthe bore of the spigot. A valve head 24on the rod 22 is seatable on a shoulder 23a to closeoff water flow through the bore of the spigot.The end 26 of the rod 22 abuts the pick and duringdisplacement of the pick into its holder in responseto cutting engagement of the pick with the mineral,the valve head 24 is displaced to permit water flowto the ports 12. When the pick disengages fromthe mineral, water pressure on the pick and valvehead 24 closes the valve head to seal against theshoulder 23a.