GB1053328A

GB1053328A -

Info

Publication number: GB1053328A
Authority: GB

Abstract

1,053,328. Screw conveyers; pneumatic conveyers. GEBR. BUHLER. Sept. 2, 1964 [Sept. 3, 1963; Nov. 7, 1963], No. 36021/64. Heading B8A. [Also in Division G1] In an automatic feed weigher arrangement in which material is fed to a weigher from a silo by a substantially horizontally disposed, weigher controlled screwconveyer 21, the screw conveyer 21 is provided with a partially blocked discharge orifice 29 to ensure efficient cut-off of the supply of material when sufficient has been fed to the weigher. The discharge orifice 29 which is situated at the outlet end of a tube 20 which may taper (Fig. 2, not shown) is blocked by a number of horizontally disposed wires 30. The screw conveyer 21 having a shaft 23 driven through a chain 25 by a motor 27 feeds material through the discharge orifice 29 to a weighing receptacle 4 pivotally mounted on one end of a beam 1 of the weigher. When the receptacle 4 deflects downwards on receiving sufficient material to counterbalance a weight 7 supported on the other end of the beam 1, a cam 10 attached to the receptacle 4 opens a switch 13 connected in the energizing circuit of the motor 27 so as to stop the screw conveyer 21 and cut-off feed to the receptacle 4. A compensating weigh arm 15 pivotally fixed at one end 16 and provided with a movable weight 17 bears on the end of the arm 1 which supports the receptacle 4 and is arranged to correspond to the weight of inevitable afterflow of material falling into the receptacle 4 when the screw conveyer 21 is stopped. The silo 38 supplying material to the conveyer 21 is provided with sloping porous deflecting plates. 42, 43 and 51 arranged above chambers 44, 46, 53 connected to a compressed air supply throughtubes 47 and 54. A device 49 in the silo 38, on sensing the absence of material in the region of the inlet to the conveyer 21, is arranged to actuate a valve 48 to supply air to the chambers and thereby to agitate the material in the silo and to urge it through a throat 52 towards the screw conveyer 21.