Improvements relating to apparatus for filling valve bags

摘要

808,437. Weighing apparatus. SMIDTH & CO., A. S., F. L. April 16, 1956, No. 11524/56. Class 143 Apparatus for simultaneously filling a number of valve bags with a predetermined weight of fluidized pulverent material, comprises a stationary tank 1 feeling bag supporting spouts 7, each supported by a weigh beam 26 of an automatic feed weigher, cam controlled mechanisms for initiating feeding, and for re= leasing filled bags from the spouts, and a single shaft 12 mounting all the cams so that the operating cycles of all the weighers are of the same duration and are interrelated. The operation of each weigher is as follows, with a bag clamped by bell crank 50 to the spout, a cam 11, acting on a roller 9 through cam follower 15, lever 13, and rods 19, 20, moves the roller 9 to the right against the action of spring 82, and permits material to flow from tank 1 through rubber tube 6 and spout 7 until the weight of the loaded bag plus the weight 37, which bears on beam 26 through rod 36, collar 41 and rods 25, is sufficient to overcome the counterweight 31 so causing the spout and its supporting frame 24 to descend. An abutment 43 is moved downwardly by frame' 24 and releases a catch 85 and so allows rotation of a notched boss 17 on a lever 42 pivoted to the lower end of lever 13 and thereby releases catch 18 and allows roller 9 to compress tube 6 and so stop the flow of material. At this point a portion 40 on cam 33 (Fig. 5) acts through a lever 35 and raises rod 36 so that the frame 24, no longer subjected to the action of weight 37, rises and, due to follower 15 being in dwell 45 of cam 11 at this instant, the catch 85 engages abutment 43. Next portion 46 of cam 11 engages follower 15 and roller 9 is moved into position to allow a restricted flow through tube 6 which continues until frame 24 moves downward for the second time and tube 6 is again compressed. At this stage projection 39 on cam 33 causes rod 35 to raise rod 36 sufficiently to cause a hook 38 to engage an abutment 87 on a pawl 48 and lift this pawl out of engagement with a roller 88 on a rod 89 rigid with spout 7 so allowing the spout to swing about pivot 23 and thereby discharge the filled bag. A dwell 38 on cam 11 ensures that catch 85 reengages abutment 43 when the frame 24 rises to start the next cycle. The material in tank 1 is fluidized by air passing into the tank through chamber 3 and porous plate 2, and is fed to pipe 6 by a paddle 72 driven in timed relation with shaft 12. The tube 6 can be compressed at any time during the cycle by manual operation of a lever 21 which disengages catch 18 from the notch in boss 17. In a modification (Fig. 7 not shown) means are provided for preventing discharge of a bag in the event of the weight of the charge being less than a predetermined amount at the instant when hook 38 is raised. In a further modification (Fig. 6 not shown) flow through the spout is prevented if a bag is not in place on the spout.