GB732821A - Improvements in cigarette weighing machine - Google Patents

Abstract

732,821. Weighing apparatus. AMERICAN TOBACCO CO. Oct. 14, 1953 [Oct. 17, 1952], No. 28332/53. Class 143. [Also in Group XXXVIII] In a cigarette weighing machine cigarettes in a hopper 2-3, Fig. 2, are fed singly by a grooved roller 4, rotated at constant speed, into notches 17 on the bifurcated end 16 of a balance beam 13, the cigarettes being released from the roller under gravity by a trip plate 9, rocked to the dotted position at the appropriate release times. After each weighing, an ejector arm 18 is rocked about its pivot 19 to lift the cigarette from the balance so that it rolls down the ejector arm on to a travelling belt 20. Weighing and recording. The balance beam is deflected as a cigarette falls thereon against the bias of a spring 23 and moves correspondingly the armature 31 of a differential transformer 28. Oscillation of the beam is prevented by dash pots 24. The similar secondary windings 30 of the transformer 28 are connected in opposition to similar opposed primary windings 36 of a second differential transformer 34, Fig. 1, the armature 37 of which is carried by an arm 39 pivoted at 40. The primary of transformer 28 is fed with A.C. so that the secondary 35 of transformer 34 yields an output dependent in magnitude and phase sense on the relative positions of the two armatures in their respective coils. The output is zero in the neutral position of the balance beam. As a cigarette is fed on to the beam an output is derived from the secondary 34, amplified, and after passing through a phase discriminator, fed to a two phase motor 43, Fig. 4 (not shown), which through gearing drives a cam 47 to rock the arm 39 and move the armature 37 until electrical balance is achieved. The angular position of the motor shaft which is a measure of the weight is translated by a cord 50 driven by a pulley 49 into a corresponding linear position of a recording pen 53 across a chart C carried in a frame 52, the pen being controlled in known manner to make a record mark on the chart as electrical balance is achieved. The chart is raised in timed steps through a ratchet, pawl, and pinion-rack device, Fig. 5 (not shown), by a spring stressed by a solenoid energized by the trip-plate 9, Fig. 2, as it is rocked to release a cigarette on to the balance. When a cigarette is ejected from the balance beam after being weighed the balance beam and hence the recorder return to neutral before the next cigarette is fed on to the balance.