GB1462177A - Safety guards - Google Patents

Abstract

1462177 Machinery safety devices; hydrostatic transmission control TORRANCE & SONS Ltd 24 July 1974 [2 Aug 1973] 36761/73 Headings F2J and F2W In a mixing machine, e.g. for paint manufacture, having a vertically-movable rotatable mixer shaft 12 carrying mixer blades 13 and driven by an hydraulic motor 14, the mixer shaft and blades are surrounded by a protective cage 7 rigidly attached to the casing of the motor 14 and extending downwards from the driving motor 14 to surround a mobile mixing vessel 11 when the arrangement is in the operative position shown, the motor 14 being automatically stopped when the unit comprising the motor 14, mixer shaft 12, blades 13 and cage 7 are jointly raised (Fig. 1, not shown) for removal of the mixing vessel 11. The unit is supported on an arm 15 of a vertical sleeve 16 which vertically slides on a pillar 27 of the machine via the drive from an electric means (not shown) controlled manually by a lever 19, on a control console 18, for raising or lowering the mixer unit and cage &c. from or into the mixing vessel 11. The hydraulic delivery circuit from a pump 22 to the motor 14 is manually controlled by a lever 23, which control is automatically overridden when a control rod 29, connected by linkage 30 to the pump delivery control, is inwardly moved by a linearly movable cam 24 fast on the vertically movable sleeve 16, to stop the pump delivery and thus stop the motor 14 when the mixer unit is raised clear of the mixing vessel and exposes the mixer blades. Additionally the pump delivery control linkage 30 and rod 29 are connected via a bellcrank 31 and Bowden cable 32 to automatically return and restrain the manual control lever 23 in the "OFF" position during the raised i.e. unsafe position of the mixer unit.