| 摘要 |
1,242,461. Weighing apparatus. CARTER ENG CO. March 25, 1969 [April 16, 1968], No.15496/69. Heading G1W. [Also in Division B8] An apparatus for filling containers with particulate material, such as powder, in a vacuum environment comprises a container 5 which is connected by a bracket 30 to a load cell 23 which is covered by a shroud 24 detachably secured to a housing 2 which is supplied with vacuum through a conduit 3, the load cell 23 having a fluid-reaction surface which is operable to nullify the effect of the vacuum environment within the housing 2. The container 5 is adapted to support a bag having its upper end fitted over a filling nozzle which is coupled to a source of material. Supply by a flexible coupling 8. The load cell comprises a stacked series of annular segments 40-47 which contain a force transmitting-rod 48 which is composed of a series of stacked segments 49-56 and co-operates, by means of a ball bearing 57, with cross beam 33 of the bracket 30, the ball 57 being retained by a washer 92 suspended by a series of chains 94. The load cell also includes a series of flexible diaphragms 60, 61, 66, 69, 72, 74, 77 which extend respectively between the annular and stacked segments 40-47 and 49-56. The cavity 62 formed by the diaphragms 60, 61 is fed with pressurized air through a pipe 63 and regulator 64, the effective area of the diaphragm 60 being greater than that of the diaphragm 61 to provide an upwardly acting-force to compensate for the tare weight of the container. The third diaphragm defines a second cavity 67 which communicates with the atmosphere through a pipe 68. A fourth diaphragm 69 having a smaller effective area than the diaphragm 66 provides a third chamber 70 which communicates with the vacuum environment in the housing 2 through ports 71, the vacuum acting upon the diaphragms 66, 69 providing a downward force exactly equal and opposite to that provided upwardly on the diaphragm 60. The oil-filled chambers 73, 75 formed between the diaphragms 69, 72, 74, provide, with ports 76 through the diaphragm 74, a dashpot to damp the movements of the rod 48. A cavity 78, between the diaphragms 74, 77 communicates with the atmosphere pipe 68. Pressure from a conduit 88 having a pressure and constant flow regulator 89 is supplied to a lower cavity 87 until the pressure therein balances the load on the cell 23 whereupon a plate 84 lifts off an orifice 81 leading to atmosphere and the pressure is stabilized and transmitted, through a conduit 90, to the recorder 38 which may have a connection to conventional control means to effect the automatic termination of filling. The container 5, which preferably has adjustable side walls to conform to the shape of the bag being filled, has a front and side walls 11, 12 pivoted at 13, the housing 2 having a front panel 20 which is pivoted at 22. |
