Patent GB-1468684-A (GB)
Title: Container filling machines
IPC: G01G13/02
Filed: 1975-05-15
Abstract: 1468684 Metering fluent material; rollerways with trolleys LOCKWOOD GRADERS (UK) Ltd 15 May 1975 [18 June 1974] 26951/74 Headings B8A and B8N [Also in Division G1] A machine for charging a predetermined amount (weight or volume) of particulate material such as potatoes into a container comprises a sizer for dividing the material into small and large size items, respective hoppers for the small and large size items, a first loading station at which the container is filled with material from the large size hopper to an amount less than the predetermined amount, a second loading station at which the container is filled with material from the small size hopper to the predetermined amount, a conveyor for transporting the container from the first to the second loading station and sensing means for sensing the amount of material in one of the hoppers, the sizer being automatically adjustable in response to the sensing means to vary the size distribution between the hoppers to compensate for changes in the size distribution of the feed to the sizer. In the embodiment described bags 35 are filled with a predetermined weight of potatoes. The conveyer comprises a runway 3 fitted with idler wheel down which bag carrying trolleys 10 run under gravity. The first and second loading stations comprise separate runway portions suspended from weighing devices 8, 9 and potatoes are supplied at the loading stations by respective conveyers 21a, 21b from a hopper 22. Potatoes are supplied to hopper 22 by conveyer 23 via sizer 24. Sizer 24 is provided with apertures of increasing size along its length, so that the potatoes which fall to the left of a dividing wall 26 to feed conveyer 21b are generally smaller than those which fall to the right to feed conveyer 21a. Above the first loading station on the runway is a bag fitting station where a bag 35 is fitted to a trolley by hand, and below the second loading station is an unloading station where a stop 40 engages a catch (16) on the trolley to release a bag. The trolleys are carried from the unloading station to be deposited at the top of the runway by a chain conveyer 19 having cross-bars 20 which engage hooks 17 on the trolleys. In use, trolleys are held at the bag fitting and loading station by catches 28. When the fitting of a bag 35 has been detected by sensor 36 and the achievement of the desired loads at the first and second loading stations has been detected by scale beam position sensors 37, 38, a chain 32 is driven until a spigot on the chain actuates a sensor 39. Drive of the chain causes spigots 33 to release the catches 28 so that each trolley moves down to a succeeding stage. The loading stations include sensors 42, 43 which are actuated by arriving trolleys to cause the conveyers 21a, 21b to be operated, and the conveyers 21a, 21b are stopped when the sensors 37, 38 are actuated. The rate of supply of potatoes by conveyer 23 is controlled by a sensor 44 on hopper 22, and the position of the sizer 24 is controlled by a sensor 45. The rate of feed at the first loading station may be decreased throughout the feed according to the weight as sensed by a strain gauge.