GB1333627A - Mining machines - Google Patents

Abstract

1333627 Mining machines CONFLOW Ltd 10 Feb 1972 [23 Feb 1971] 5196/71 Heading E1F A mining machine has safety means involving the association of a lock with the starter of the drive motor of the cutter means of the machine and this lock is such that it cannot be withdrawn clear of the starter until a predetermined time has elapsed after commencement of emission of dust supression fluid in the region of the cutter means. The delay is regulated by bleeding off fluid from a conduit of the dust suppression fluid-supply system and passing the fluid through a restriction before it directly or indirectly actuates the lock-controlling means. Said means may be a pistoncylinder unit of which the piston rod thereof can engage one or two projections, e.g., one or two opposed, spring-biassed pawls, on a shaft of the starting handle of the motor or can carry a guard that can prevent access to a push button of a starter switch of the motor. The restriction can involve an adjustable aperture needle valve and can be bypassed, the bypass having a lightly loaded, spring biassed, non-return valve allowing of release of fluid from the lock-actuating means. The machine may also have an audible warning device operated by fluid bled off from the dust suppression fluid supply. (For Figures see next page)