Patent GB-714392-A (GB)
Title: Apparatus for weighing out in a vessel quantities of different substances
IPC: G01G19/22
Filed: 1952-09-03
Abstract: 714,392. Weighing-apparatus. NAUTA, J. E. Sept. 3, 1952 [Sept. 5, 1951], No. 22184/52. Class 143 [Also in Groups XIX and XXXVII] In weighing apparatus for successively weighing out quantities of different substances in a common weigh vessel the latter operates through linkage at a remote control point against a pendulum resistant a switching member movable over adjustable contact positions in accordance with the weight in the vessel and electrically determining the quantity of substance in turn supplied to the vessel. As shown different substances are in turn supplied from storage tanks 1, 2, 3 through screw conveyers 4, 5, 6 operated by electric motors to a weigh vessel 10 suspended from rods 23 operating through linkage and a flexible band 34, a pair of flexible bands 36, 37 which rotate in opposite directions a pair of discs 40, 41 carrying pendulum counterweights 44, 45. The discs also operate through parallelogram linkage 47-49 a flexible endless band 53 biased to a taut position by a jockey pulley assembly 52-59 and operating through a roller 51 on shaft 60 which rotates the switching member 62. The member 62 carries brushes 64, 65 energized from terminals G. H over slip rings 66, 67 and a weight indicator pointer 63, and is movable over a semi-circular series of contact members 69 (Fig. 4) normally electrically connected in series by interengaging contacts (97, 98, Fig. 5) on spring tongues 99, and presenting segmental contact surfaces 68 spaced by insulation 71 to the brushes. Normally current can pass from a source 89 through the slip rings 66, 67 to the brushes and through all the series connected contact members 69 to the last member 69b and the negative terminal of the source, but when one or more jack plugs S in series with relays 86 starting the individual feed motors are plugged into selected contact members 69, the tongues on the latter are disengaged from the succeeding contact members and each relay controlled motor circuit in turn is .operative, while the brushes are on the contact members 69 connected to them. Two brushes 64, 65 in parallel are in series with the source 89, one (65) in series with a relay 90 disconnecting the other brush, and the brushes are so spaced that one but only one at a time contacts a contact member 69. The brushes are therefore alternately operative and by this means the switching member 62 is carried past a discontinuity created by a plug (by the feed motor being still operative until the trailing second brush leaves the contact member) and the next, if any, feed motor is energized. A graduated disc 77 coaxial with the shaft 60 permits the appropriate weight determining contact members to be selected by the plugs and in zero position indicates the weight. The disc may be serrated and only permitted to be adjusted in steps by a spring-biased catch. In series with the last set of contact elements 69 is a relay 100 (Fig. 4) which automatically or through a hand control switch 101 operates a relay 104, 105 actuating a motor 11 (Fig. 1) which, through a worm, drives a disc 15 and actuates crank rods 21 opening the bottom gates 20 of the weigh vessel. The disc 15 is notched and through a roller 17 opens a switch F in series with the supply source 89 so that the feed mechanism does not restart until the disc 15 makes one revolution and the vessel contents are fully discharged. Further the roller 17 closes a switch E in series with the relay coil 104 and auxiliary source 102 so that the motor 11 remains operative even although the initiating relay 100 is no longer effective. More than one selection plug may be provided for each substance so that the substances supplied may be mixed. The plugs &c. and switching unit may be mounted in a common box.