GB790480A - Improvements in dust suppression for grinding wheels - Google Patents

Abstract

790,480. Grinding. BRITISH CAST IRON RESEARCH ASSOCIATION, and CONSOLIDATED PNEUMATIC TOOL CO., Ltd. Oct. 18, 1955 [July 18, 1954], No. 18042/54. Class 60. [Also in Group XXVIII] In a grinder the grinding wheel 1 is porous and is mounted on a shaft 2 having a longitudinal bore 6 which communicates at one end, through a radial port, with the interior of the wheel hub and at the other end, through another radial port, with a cavity 17 in a housing, the cavity 17 constituting or communicating with a source of supply of coolant liquid for the wheel to suppress dust. The grinder is portable, the shaft 2 being driven from a built-in air or electric motor or through a flexible shaft from a fixed power input ; the shaft 2 rims in a sleeve 3 which provides a hand grip and which is supported from the frame of the machine, the latter carrying a cowl normally enclosing about one-half of the wheel. A two-part housing 11a, 11b surrounds as a good running fit, a bush 12 secured, as a snug fit, on the shaft 2 ; the housing part 11b is screwed into the end of the sleeve 3. The rear end of the bush 12 abuts the inner race of a ball bearing 13 housed in the end of sleeve 3, seepage from the housing 11a, 11b along bush 12 into bearing 13 being prevented by a helical groove 14 in the bush. The housing parts 11a, 11b are connected by screw-thread 16 leaving an annular cavity 17 which is enlarged around the bush 12 by recesses 18, 19 containing resilient gland washers 20, 21. An inlet port 24 in the outer annular wall of the housing part 11a communicates with a connector 25 for a water pressure line. The shaft 2 and bush 12 have a radial duct 22 and a port 23 in register, the duct 22 opening into the bore 6. A radial duct 27 in the shaft 2 registers with a port 28 in the bush 29 of the wheel 1, the latter having its central bushed hole enlarged at 30 to form an annular cavity in which the water collects prior to passing outwards to the working face of the wheel through the pores. By reducing the head of water at the input to a very low value the flow can be made dependent on the rotation of the wheel so that liquid is flowing when the wheel is rotating and not flowing when the wheel is not rotating.