Patent GB-1311032-A (GB)
Title: Packaging machinery
IPC: B65B1/34
Filed: 1970-10-07
Abstract: 1311032 Packaging particulate materials F W CLEGG 6 Oct 1971 [7 Oct 1970] 47673/70 Heading B8C A machine for dispensing successive weighed quantities of produce or material, e.g. potatoes, comprises a first conveyer having a relatively large delivery rate discharing into a first net weight container 26, a second conveyer having a relatively small delivery rate discharging into a second net weight container 28, means to supply produce or material to the conveyers, means responsive to a weight of produce or material somewhat less than the quantity to be dispensed having been received by the first container and operative to discharge the contents of the first container into the second container, means to permit discharge of material or produce from the second container when the full weight to be dispensed has been made up by material or produce from the second conveyer and means to prevent discharge of the contents of the first container except when the second container is empty. As shown, produce, e.g. potatoes is fed from a hopper 2 by two elevator belts 4, 6, the hopper being divided by a vane 10 into two compartments 12, 14 supplying the belts 4 and 6 respectively. The belts 4, 6, discharge into vibrated troughs 16 and 20, the amount of produce in the troughs being controlled by proximity switches 22, 24 and the troughs discharging into the containers 26 and 28 provided with discharge gates 38 and 40 respectively. The gates are biased to closed positions from which they are unlatched by devices 42, 44 each comprising an actuator 122, supported on a bracket 124 by parallel links 126, 128, the brackets being carried by cabinets 52 and 58 respectively. A pneumatic ram 94 or 110 respectively acts on link 128 to cause vertical movement of actuator 122 which opens or closes gates 38 or 40. The container 26 is sup - ported by pillars 48 from a platform 50 of a steelyard weighing mechanism of known type and cabinet 52 and container 28 is supported by pillars 54 from a platform of a steelyard mechanism in cabinet 58. Flags 60, 62 on the indicating arms of the steelyard mechanism are associated with photo-electric cells 64, 70 which control the feed to containers 26 and 28. The apparatus is controlled by pneumatic and electric circuitry described with reference to Figs. 6 and 7 (not shown) in which closure of a main switch (106) when the container 28 contains the correct weight as recorded on a scale 112, effects discharge of the container 28 through a shoot 46 to which a bag or sack may be applied. Overweight on the container 28 is prevented by a photo-cell (72) which operates a relay (76) to effect opening of trap door 116 to the shoot 46 to divert the produce in the container 28 to a conveyer (not shown) for return to the hopper 2. The arrangement is such that operation of the gate 40 is prevented whilst the container is empty and that there is no feed to the container 28 either when it is empty or when it is substantially under filled. When the container 26 is filled to the quantity pre-set by means of the associated steelyard mechanism, the gate 38 is opened to discharge into the container 28 which is then filled to the required weight by operation of trough 20, the produce in trough 16 being replaced by operation of belt 4.