Patent GB-624172-A (GB)
Title: Improved means for bunker filling control
IPC: B65G47/00
Filed: 1946-02-19
Abstract: 624,172. Controlling level of material in hoppers ; hoists. HUMPHREYS & GLASGOW, Ltd., and LIDDLE, H. Feb. 19, 1946, No. 5179. [Classes 78 (i) and 78 (iii)] A filling installation for feeding material to a bunker or the like comprises means driven by an electric motor for bringing a skip into and out of a discharge position above the bunker and a probe, adapted to prevent overfilling, arranged for reciprocation towards and away from the material in the bunker and which is connected through a toggle to a switch controlling the motor so that the motor is stopped when the toggle is collapsed as a result of the downward movement of the probe being impeded by the material in the bunker, the probe lying normally in a lowered position and being lifted out of that position and lowered into it as a consequence of the movement of the skip into and out of the discharge position. In Fig. 1, a bunker B is filled by a skip S which runs on wheels 15, 1.6 on tracks 17, 18, the skip being drawn into its discharge position, tipped automatically and then drawn back along the track to its loading position by hoisting mechanism actuated by an electric motor controlled by a switch M. The probe rod 7, reciprocated in a tube 8, is connected to toggle links 5, 6, the link 5 being connected to a weighted lever 4 from which depends a rod 3 connected to a cranked lever 2 mounted on a pivot 2a. The toggle is connected by a rod 11 to a lever 12 which in the position shown maintains closed the contacts 14 of the switch. When a loaded skip reaches its discharging position, its wheel 16 depresses the lever 2 from the dotted to the full line position and thereby lifts the rod 7. After discharge, the skip travels back down its tracks whereby the lever 2 is released and moves to its dotted line position and the rod 7 drops. If the material in the bunker has risen beyond the limiting pre-determined level, the downward movement of the rod 7 will be arrested but the weighted lever 4 continues to descend and cause the toggle to collapse to the position A<SP>2</SP>. Outward movement of the knuckle of the toggle causes the lever 12 to be pivoted clockwise so as to open the contacts 14 and stop the motor. Fig. 3 shows the application to a bottom-opening skip discharged as described in Specification 619,045 by a ramp 24 which may be set in an operative or inoperative position as shown in full and dotted lines respectively. When the skip reaches its discharging position along the rail 18, its wheel 16 raises the lever 25 and the weighted lever 20 so as to lift the rod 7. When after discharge the skip moves away, the lever 25 is turned by the lever 20 until it contacts the stop 25a and the rod 7 is lowered. If the material in the bunker exceeds the limiting level, the downward movement of the rod 7 is arrested and the toggle collapsed into the position A2 and the switch M opened. On now raising the ramp to its inoperative position by the operating lever 23, the levers 20, 25 are raised by the chain 22 and the toggle straightened to close the switch. A loaded skip may now pass on to the next bunker.