Patent GB-220052-A (GB)
Title: Improvements in or relating to conveying installations
IPC: B66B17/32
Filed: 1923-05-05
Abstract: 220,052. Rushen, P. C., (Siemens- Schuckertwerke Ges.). May 5, 1923. Shoots; loading hoppers.- In hoisting appliances of the type in which two receptacles are raised and lowered alternately by a single winding engine the one being raised as the other is lowered, the automatic starting of the winding engine is dependent upon the combined operations of loading and unloading, the arrangement being such that the engine cannot be started until both loading and unloading are completed or has reached a predetermined stage necessary for the working of the apparatus. The invention may also be extended by arranging that the winding motor cannot be started until all the moving parts of the installation, such as the charging hoppers and discharging shoots, have attained definite safe positions relatively to the moving receptacles. Fig. 2 shows one arrangement of circuits bv which a main winding motor 16 is controlled. The positive and negative mains each are bifurcated as shown, the positive main being connected through switches 8, 10 in parallel and a bi-polar reversing switch 6 to the motor, while the negative main is connected through switches 7, 9 in parallel and the switch 6. At the time when the right hand skip is at the bottom of its travel and is being loaded from a measuring hopper, while the left hand skip is at the top and being discharged into a shoot, the lower skip during its previous downward journey has opened the right hand switch 8 mechanically and in so doing closed the left hand switch 8. The upper skip at the same time has similarly operated and reversed the switch 6 to bring it into the position shown in Fig. 2, and by mechanical interconnection has also opened the left hand switch 7 and closed the right hand one. The reversal of the switch 6 puts the motor into position for raising the right hand skip and lowering the left hand one, but before winding can commence the motor circuit has to be completed by the closing of the left hand switch 9 and the right hand switch 10 operated by the movement of the shoot and the closing of the mouth of the measuring hopper respectively. The installation is arranged as shown in Fig. 1 with the skips 5 being loaded from measuring hoppers 2 and being discharged into shoots 1. Fig. 1 shows the position in which the upper skip 5 has been emptied into the shoot 1, and the lower one filled from the hopper 2. The flap 13 in the shoot, in returning by gravity to its original position after being displaced by the passing material, has switched in the auxiliary motor 4 through the medium of the ratchet switch 12 to move the shoot out of the path of the skip. When the ratchet wheel 12 strikes a fixed stop 14, the auxiliary motor is stopped by mechanism which also re-sets a lever 11 in the path of the next rising skip so that the latter will start the auxiliary motor during the ascent and thus position the shoot to receive the load. Similarly other levers 11 are positioned in the path of the falling skips to start the motors for opening the measuring hoppers. During the return movement of the shoot, a stop on the bottom closes the switch 9 while the right hand switch 10 is closed by the closing movement of the mouth of the measuring hopper. The main winding motor thus being started, the skips are operated until the rising one again reverses the switch 6 and the falling one opens the left hand switch 8 and thus closes the right hand one. The whole installation can be timed so that the measuring hoppers and the shoots begin to be operated as soon as it is safe, and before the skips actually arrive at the end of their journey.