Patent GB-483592-A (GB)
Title: Improvements relating to skip winding
IPC: B65G67/00
Filed: 1937-01-21
Abstract: 483,592. Skip-loading and hoisting in mines. INTERNATIONAL COMBUSTION, Ltd., and DAVIDSON, G. W. Jan. 21, 1937, No. 1808. [Classes 78 (iii) and 78 (iv)] Comprises automatic control of loading and unloading operations in skiphoisting installations for mines, and includes automatic feeding of tubs one by one into a tippler at the bottom of the shaft, automatic rotation of the tippler in timed relation to the feeding by the movement of the tubs, stoppage of the feeding and tipping when a predetermined number of tubs have been discharged into a loading bunker, automatic discharge of the bunker into the skip on arrival of the latter from the pit-head, prevention of discharge until the bunker has been loaded with the predetermined number of tubs, and preventing the re-winding of the skip until it has been correctly loaded. The mechanism may be combined with double-door deliveryhoppers at the top of the shaft, for example as described in Specification 468,860. Figs. 5, 6 and 7 illustrate the mechanism at the bottom of the shaft of which Fig. 6 shows the state of affairs when the tippler 9 has completed its revolution after discharging tub TR<1> which is ready to be pushed off, tub TR<2> is being held by stops 33 with its axle engaged by members 31 ready to be pushed by rams 10 on to the tippler, and tub TR<3> is being held by stops 34 prior to arriving within the range of action of the rams. Other tubs will be delivered by gravity or positive hauling means successively to these positions. The pneumatic control includes three valves 19, Fig. 5, 12, Fig. 6, and 13, Fig. 7 in series between the pressure main and the apparatus, of which 19 is nearest the main and is closed by the operation of counting-mechanism for the tubs and re-opened when the filled skip commences to ascend, 12 is next in sequence and is controlled by the position of the tippler and 13 actuates and is controlled by the ram. Thus, the closing of valve 19 stops both tippler and ram, while the closing of valve 12 stops the movement of the ram. Prior to the ram 10 making its forward stroke, the stops 33 are retracted and the stops 34 raised pneumatically consequent upon the positioning of the valve 13 for this forward movement. When the ram moves it (1) operates the counter 85 whereby a switch arm is moved one step at a time over a series of contacts eventually completing a circuit at a selected contact to close valve 19, (2) it trips the lever 40 in passing, which moves idly in the slot 43 and is restored by the counterweight 45, (3) it operates an arm on the shaft 37, which movement is communicated by link 46 to the shaft 47 to reverse the valve 13, and at the same time positions an arm on the shaft 47 for contact with it on its return stroke, (4) it pushes the tub TR<1> out of the tippler. As the tub runs off it strikes a lever 57 and raises the axleengaging levers 55 into position to catch the succeeding tub. A member 63, moved axially by one of the driving wheels of the tippler, withdraws the levers 55 as the tippler completes its turning movement. The reversal of valve 13 at the end of the forward stroke automatically operates valves which re-raise the front stops and lower the rear stops, thus allowing tub TR<3> to run in and take up the position previously held by TR<2>. On the return stroke of the ram (1) the lever 40 is actuated thus causing the link 44 to pull on the lever 23 and engage the driving clutch 2 to start the tippler, (2) the member on the shaft 47 is operated to again reverse the valve 13 ready for forward movement and re-set the projection on the shaft 37. When the tippler commences to rotate, the projection 9a releases the roller 50 and allows the compression spring 52 to close the valve 12 thus preventing the next forward stroke of the ram until contact is re-established at the completion of the tipping movement. At this point a projection 96 on the tippler engages the roller 54 and uncouples the driving clutch 29. In addition the beak 23a of the clutch-operating lever acts as a positive stop for the tippler which is removed when the clutch is re-engaged. Fig. 4 shows the control-mechanism in its relation to the position and movement of the skips in the shaft. The top and bottom doors of the two delivery bunkers into which the balanced skips discharge at the pit-head control the movement of switches X<1>, X<2>, Y<1>, Y<2>. When the skip serving the " X " bunker arrives at the surface, the top door of the bunker is opened and switch X<1> correspondingly closed. The outlet door of the " Y " bunker being open in the absence of its skip, the switch Y<2> is correspondingly also closed, so that a circuit is completed through a timing relay 5T which after an adjustable predetermined interval closes a switch 5TA to lower the skip again. At the end of its run the descending skip closes a contact S. In the meantime the counting-mechanism previously described has been operating the arm SRA step-by-step until finally contact is established with the arm CS. This energizes coil B and causes a solenoid K to close the main valve 19 to stop the tippler and the rams, and in addition closes contacts Bb, Cc. These latter contacts, with the switch SS closed, complete the circuit of a coil C actuating a re-setting coil RSR which returns the arm SRA. Meanwhile the other skip at the surface has discharged its contents and is ready to descend. It cannot move, however, until contact CAX is made by the energizing of coil C, thus completing the circuit of the coil 5T. On the skip at the bottom rising, contact SS is broken, the coil B de-energized and the valve 19 re-opened. Fig. 5a shows the differential valves employed. The valve proper, provided with two heads 104a, 104b alternatively engaged with their adjacent seatings, is fitted with a larger piston 108 to secure the differential action. Ports 103 and 107 lead to the pressure main, port 102 to the device to be controlled, and port 101 to exhaust. A spring 105 opens the valve to exhaust in the absence of pressure in the port 107.