Patent GB-852126-A (GB)
Title: Machine control systems
IPC: B65B57/00
Filed: 1958-04-15
Abstract: 852,126. Conveyers. PACKAGE MACHINERY CO. April 15, 1958 [June 3, 1957], No. 11901/58. Class 78 (1). [Also in Groups XVII and XXXV] Two machines for operating on articles passing through them on endless conveyers have driving means incorporating synchronizing devices whereby either machine may be started independently of the other and their cycles of operation will automatically synchronize regardless of which is first started. The invention is illustrated as applied to two biscuit making machines feeding their products to a wrapping machine the latter being as described in Specification 770,124, the object being to synchronize the biscuit machines with the wrapping machine, with a single power source driving them all. Biscuit feed.-The biscuit machines 30, 32 (not detailed) discharge biscuits along channels 34, 36 by conveyer chains 204 with upstanding pins 202 (Figs. 1, 2, 9). The biscuits fall on to the floor of channels 38 and remain until another biscuit has been fed on top of them, the stacked pairs then being engaged by pins 40 on chains 162, 196. The pairs are carried into a pivoted trough 39 movable by a solenoid 232 to direct the biscuits into upper or lower paths. Biscuits are automatically diverted to the upper path if synchronization has not been fully achieved or may be so diverted as desired for inspection of samples &c. Under normal circumstances biscuits take the lower path and are engaged by flights 44 of a conveyer 90 for transit to the wrapping station W of the wrapping machine 46. Magazine storage and auxiliary feed.-Biscuits on the upper path are stored in magazines 48, 50. The conveyers 162, 196 feed them along curved tracks 242 and beneath springs 261 to wheels 244, Fig. 12, which set them on edge on rails 268 of the magazines. During such storage or in the event that a biscuit machine is not running (e.g. a break in the sequence of biscuits in the channels 34, 36 causes a feeler switch 209, Fig. 21, to initiate machine stoppage), biscuits are automatically fed from auxiliary sources to the wrapping machine. These sources comprise magazines 56, 58, the discharge ends of which curve downwards to deposit biscuits adjacent the conveyer flights 44 (Fig. 2). Pushers 52, 54, detailed in Fig. 14 (not shown) thrust the biscuits in pairs into the path of the flights 44. The pushers are operated by cams rotating with the wrapping machine drive, but the cam follwers are held clear by solenoid-operated latches during normal operation. Drive and synchronizing means.-All three machines are driven through chains, sprockets and magnetic clutches from a motor 60 (Figs. 1, 3) mounted on the wrapping machine. The motor drives a constantly rotating shaft 66 which rotates a sprocket 74 through a chain 76. A magnetic clutch 80 is engaged to rotate a shaft 78 which drives the wrapping machine and the pusher cams. The shaft 66 also drives through a chain 118 a sprocket 116 which may be connected through magnetic clutches to sprockets 128, 130 operating machines 30, 32 respectively through chains 134, 168. Passing axially through these clutch assemblies but not connected to them is a shaft 94, which is driven by the wrapping machine drive shaft 78. Each biscuit machine clutch has associated with it a plate 470, Fig. 6, rotating with the shaft 94 and carrying a switch 468 (see also Fig. 7) which is actuated by a cam 466 mounted on a wheel 464 fast with the machine driving sprocket 128 or 130. All clutches have associated magnetic brakes. Assuming the wrapping machine to be running when either biscuit machine is started up, the brake coil 454 is released and a pulsating current is applied to the respective clutch coil 428 to cause a slipping engagement and corresponding rotation of the biscuit machine drive sprocket 128. The wheel 464 also rotates so that its cam 466 engages the switch 468 causing current to fully connect the clutch and the biscuit machine to be driven in synchronism with the wrapping machine. The chains 134, 168 drive shafts 136, (172), Fig. 1, which in turn drive the conveyers 162, 196 and 204. These shafts have cams at their ends operating make-and-break timing switches 531 (Figs. 17, 18, not shown) which are in circuit with the solenoids 232 and 252 controlling the trough 39 and pushers 52, 54. These ensure that the change over from direct feed to feeding from the magazines 56, 58 and vice versa is correctly timed to avoid these actions taking place when biscuits are only incompletely discharged by the pushers or ramp. All the machines may be operated separately by inching switch arrangements for delivering samples &c. and the wrapping machine circuit includes switches operated by absence of wrapping material to stop the machine. Synchronizing circuits.-Each biscuit, machine includes substantially identical circuits, that of one of them being shown in Fig. 21. Motor and wrapping machines circuits are illustrated in Figs. 19, 20 (not shown). Starting the motor and wrapping machine closes switches, 516-6 and CR 1-3 (line 3A) and CR 1-4 line 5A, the latter causing solenoid 252 to bring the respective pusher into operation to feed. biscuits from the magazine. When start button 496-1 is depressed, brake coil 454 (line 3) is deenergized and current applied via rectifier 524 and variable resistor 526 to a relay PR 2 and a capacitor 528. Operation of the relay opens a switch PR 2-1 (line 3A), cutting off current to the relay, and closes a switch PR 2-2 putting in circuit the clutch coil 428 lines 3F, 3E. The relay PR 2 is held operative by flow of current to the capacitor for a short period and then returns, cutting off current to the coil 428 and restoring it to its own coil. The clutch coil thus receives the pulsating current to rotate the machine until switch 468 (line 3H) is closed by the cam 466. Then a relay DR 2 is operated, opening a switch DR 2-1 to isolate the pulsating relay, and a switch DR 2-3 closed to place the coil 428 fully in circuit. Operation of relay DR 2 also closes a switch DR 2-2 (line 4) bringing into circuit the timing switches 531 and a relay DR-21. Operation of the latter isolates solenoids 232 and 252 to cause feed of biscuits to the wrapping machine from the respective magazine to cease and correctly position the trough 39 for direct feed.