GB318281A - Improvements in and relating to automatic feed weighing apparatus - Google Patents

Abstract

318,281. Davis, F. W. June 1, 1928. Automatic-feed weighers.-Apparatus for delivering a predetermined weight of liquid, granular or pulverized material at predetermined intervals of time is characterized in that the supply of material to the weighing beam is cut off on the recoil of the weighing beam after discharge of the material. In one form of the invention a screw conveyer delivers granular material from a hopper R to a compartmented drum N carried on a scale beam P and discharging and re-setting itself in known manner. The screw conveyer is rotated, to feed the material, by means of a ratchet wheel C, a pawl B, and a constantly-reciprocating rod A. When the compartmented drum has received its' charge the scale beam tilts, the drum discharges-and a pin E on the beam engages and draws down a hook H connected to the pawl B by a weighted lever E and link J. The pawl is raised from the ratchet wheel C and the conveyer is arrested thus cutting off the feed. After a predetermined interval of time, a constantly-rotating timing cam M displaces the hook H from engagement with the scale beam and allows the lever E to lower the pawl B into engagement with the ratchet wheel and commence another weighing operation. The timing cam M mav be mounted loosely on the ratchet shaft D and may be operated by a second ratchet wheel and crank shaft. When the material is a liquid the ratchet wheel C and its pawl drive are dispensed with, and the weighted lever E operatesa stop cock. When several machines are used in conjunction as proportioning machines, the timing cams of the machines are coupled together so as to rotate at the same speed or relative speeds. By varying the speed at which the coupled cams are driven the rate of discharge of the total weight may be varied without altering the relative proportions.