Patent GB-705204-A (GB)
Title: Improvements in conveyor control systems
Inventor: JACKSON DESMOND JOHN
IPC: B65G47/51
Filed: 1951-08-01
Abstract: 705,204. Tingle step counting-apparatus. DONOVAN ELECTRICAL CO., Ltd. Aug. 1, 1952 [Aug. 1, 1951], No. 18179/51. Class 106 (1). [Also in Group XXX] A conveyer control system for slings or containers issuing from and being returned to a loading station by a closed circuit conveyer consists of a plurality of latched relays one of which is adapted to be set up by each sling or container issuing from the loading station, and a switch adjacent the return portion of the conveyer line in advance of the loading station and adapted to be closed by a passing sling or container, said switch being in a circuit incorporating a contact associated with each of said relays whereby if a relay is set up by an issuing sling or container a returning sling or container is allowed to pass back to the loading station, whereas if none of said relays are set up returning slings or containers are indexed on to a conveyer bye-passing the loading station. As shown, Fig. 1, a driving element equipped with dogs for engaging slings or containers on outgoing and return tracks 5, 3 is passed in a loop 4, 8, and the arrangement is such that the returning empty slings or containers are diverted to a loading station 6, 7 after which the loaded slings or containers issue on to the outgoing run 5. In order to ensure that the loading station is not overfilled, and also to provide for deficiencies to be made up in the case of slings or containers issuing on to the outgoing run 5 in excess of empty slings or containers being diverted into the loading station, owing to certain returning dogs being empty, latched relays LR1, LR2, LR3 are provided, Fig. 2, the closing coils LR1.C, LR2.C, LR3.C of which are in series with the contacts A, A1, A2 respectively all arranged within a dog pitch of the driving element while the tripping coils LR1.T, LR2.T, LR3.T of which are in series with contacts C, C1, C2 also arranged with a dog pitch of the driving element, the contacts all being operable by passage of a sling or container. As shown the contacts are made operable in sequence by means of switches brought into operation by the various relays in turn whereby the slings or containers are counted both out of and into the loading station. Thus if all the returning dogs propel a returning empty sling or container and a loaded sling or container is fed to each dog on the outgoing run, then immediately after the contacts A, A1, A2 have been actuated by one outgoing sling or container the contacts C, C1 C2 are actuated by a returning container to trip the relay set up by the contacts A, A1, A2. However, if a gap occurs in the outgoing slings or containers, all the relays are inactive as a returning container approaches contacts C, C1, C2. In this case a contact B placed in juxtaposition to the contacts C, C1, C2 but just in advance of them completes a circuit through the closing coil LR4.C of a relay LR4 which causes operation of a diverting member to index the sling or container on to a byepass track 9. Upon this sling or container passing a contact D on track 9 the relay LR4 is tripped as shown. As shown, contacts of the relays LR1, LR2, LR3 are in series with the closing coil LR4.C, these contacts being closed only when the relays are inactive. Since the latched relays can count up to three slings or containers going out for one returning sling or container this allows for eventual replacement of slings or containers in the storage area if up to two of the returning dogs are empty, since relay LR4 can only be operated when all the relays have been tripped. This number can be increased by increasing the number of relays and associated contacts.