Patent GB-777921-A (GB)
Title: Automatic wagon loading gear
Inventor: BARDSLEY NORMAN
IPC: B65G57/00
Filed: 1951-08-11
Abstract: 777,921. Stacking-machines. SUTCLIFFE, SPEAKMAN & CO., Ltd. Nov. 11, 1952 [Aug. 11, 1951], No. 18956/51. Class 94(1). [Also in Group XXX] Articles to be stacked are first laid in a single layer on a wheeled pallet 9, Fig. 1, or other platform and the layer is then transferred to a wagon 17 which is lowered through the thickness of a layer each time a layer is added to it. In the machine illustrated bricks moulded on a press table 7 shown in plan in Fig. 2 are stacked on a wagon 17. A double line of bricks 6 is pushed from the press-table 7 onto a wheeled pallet 9 which is then moved along rails 12 through the width of a double row to receive a further double row, so building up a layer of bricks on the pallet. When a complete layer of bricks has been formed on the pallet its place is taken by a similar pallet and it is moved onto a track 14, Fig. 1, which is lowered into alignment with a fixed track 13. The pallet is then moved rearwardly over the track 13 so that a fixed plough 16 strips the layer of bricks from the pallet to fall onto a wagon 17 and the pallet is delivered to a track 15 which is raised into alignment with the fixed track 12 so that the unloaded pallet may take the place of the pallet being loaded from the press-table. After each layer of bricks has been delivered to the wagon 17, which stands on a hoist 19, the wagon is lowered through the height of one layer of bricks. After a sufficient number of layers of bricks have been delivered to the wagon it is pushed off the hoist 19 by a following empty wagon (see Group XXX) which is then raised by the hoist 19 to be similarly loaded. Pushing the bricks onto the pallets. The bricks are pushed in pairs from the press-table by a reciprocating pusher 20, Fig. 5, sliding on rods 21 and carrying depending links 45, 46, Fig. 7, which carry members for gripping the sides of the bricks. As the pusher 20 is moved forwardly by a linkage operated from a cam, rollers 50 on the links 46 engage fixed cam surfaces 60, Figs. 5 and 6, by which the members 50 are swung inwardly against the action of compression springs 53 to move the pairs of bricks together. The bricks move onto the pallet over a draw-bridge comprising a central guide 62, Fig. 13, and side bars 63 carried by arms 64 which may be turned with their shafts 65 by a suitable linkage when defective bricks are to be discarded to a reject conveyer (not shown). From the drawbridge the bricks pass over a shelf 78, Fig. 11, suspended by swinging links 80, 82 and biassed away from the pallet by springs 84 ; thus after each pair of bricks have been pushed onto the shelf the shelf is retracted slightly by the springs 84 to leave a gap between the last brick on the shelf and the first brick on the pallet. Rollers 87 adjacent the shelf 78 keep the bricks of each pair in contact. Moving the pallets during loading. After each double row of bricks on the pallet has been completed the pallet is moved through the width of a double row by the mechanism described in Specification 777,922. The pallet being moved is coupled to pull a pallet behind it by a projection 103, Fig. 16, engaged by a hook 91 pivoted at 92 to the rear pallet and disengaged before the forward pallet is to be lowered on the rails 14 by engagement of a ramp 203, Fig. 24, with a roller 95 on the latch. Raising and lowering the tracks. The rails 14, 15 by which the pallets are raised and lowered between the rails 12, 13 are carried by links 175, Figs. 24 and 29, operated through linkages from pneumatic rams 159, 160. As a pallet being loaded moves along the fixed track 12 a cam 177 on it operates a cam or micro switch controlling a pneumatic pilot valve S which in turn controls relay valves P, Q which cause the rams 159, 160 to raise the tracks 14, 15 into alignment with the fixed track 12, the track 15 raising an empty pallet which is automatically coupled to the pallet on the track 12. When a loaded pallet has moved onto the track 14 the cam 177 operates a pilot valve R which acts through the relay valves P, Q to cause the tracks 14, 15 to be lowered onto fixed brackets in a position in alignment with the fixed track 13. The movements of the rails 14, 15 may be damped by dashpots 190 and by restrictions in the ports of the rams 159, 160 and of the valves P, Q, R and S. The pallets are locked on the tracks 14, 15 by catches 158, Fig. 24, engaged by the hooks 91 which are released by fixed abutments (not shown) when the downward or operative movement of the track 14 or 15 is complete. Stripping the bricks from the pallets onto the wagons. When a loaded pallet has been lowered by the track 14 it is moved rearwardly over the fixed track 13 by engagement of projections 99, Fig. 16, with an endless driving chain 204, Fig. 1, During the rearward motion of the pallet the layer of bricks is stripped from it, to fall onto the wagon, by a plough 16, Fig. 1, which may be rubber faced and which is moved after the passage of each pallet so that alternate layers of bricks on the wagon are staggered. As each pallet moves over the fixed track 12 a roller 98, Fig. 17, on it turns a star wheel 398, Figs. 1 and 32, which is connected by chain and sprocket gearing 397, 399, 235, Fig. 32, to turn a shaft 231 carrying eccentrics 230a by which the plough 16 is reciprocated in guides 229. The plough 16 may be provided with a brickengaging face 370, Fig. 40, gradually moved back as the bricks are discharged : this is stated to reduce damage to the bricks by their faces rubbing together. The face 370 has lugs which are pivoted at 371 to bell crank members 372 pivoted at 373 to brackets 374 on the plough 16 and operated to retract the face 370 by a pneumatic cylinder 381 which acts through links 378, 375 and is damped by a dash-pot 383. The pneumatic cylinder 381 is controlled by a relay valve U, Fig. 44, controlled by pilot valves V, W operated respectively by the underside of a pallet on the track 13 and by the cam 177 of a pallet on the upper track 12. Raising and lowering the wagons. After each layer of bricks has been delivered to a wagon 17 on the hoist 19, Fig. 34, the hoist 19 is lowered through the thickness of a single layer by withdrawing from the ram 19a of the hoist a measured volume of liquid by means of a piston and cylinder 259 the swept volume of which may be adjusted by a device 262. For this purpose opposite ends of the cylinder 259 are alternately connected to a liquid reservoir 251 and to the ram cylinder 19a by a rotary valve 245 which is turned through 180 degrees by a chain and sprocket connection 243 to a star wheel 241 operated by the roller 98 on the pallet on the lower track 13. This action may be interrupted by a manually operated valve 248 the control lever 247 of which may be placed in the position Y to connect a liquid pump 250 to raise the wagon hoist until it engages a limit switch 255 to cut out the motor 246 driving the pump, or may be adjusted to the position Z to lower the wagon hoist : the final lowering movement of the wagon is preferably effected manually. In the arrangement illustrated the star wheel 241 is turned through 90 degrees at each operation so that a 2 : 1 ratio to the valve 245 must be provided. The star wheel 241 may, however, be duplicated, each star wheel providing 90 degrees rotation of the valve 245. The motor 246 driving the liquid pump 250 for the wagon hoist is switched on by a limit switch 335 operated by the mechanism for propelling the wagons onto the hoist : the hoist is not however raised until the manual control 247 is operated. Specification 670,678 [Group II] also is referred to.