GB787974A - Improvements in or relating to weighing machines - Google Patents

Abstract

787,974. Weighing apparatus. SIMON & SONS, Ltd., R. April 14, 1955 [Jan. 14, 1954], No. 1087/54. Class 143 [Also in Group XXXV] In an automatic feed weigher provided with means for compensating for the material suspended at cut off, the means is adjusted at each weighing operation to correct the weight of the following charge. As shown the device is incorporated in a weigher similar to that described in Specification 743,530, the weigh pan (not shown) being connected to a rotary indicator 3 provided with a contact 3a, which co-operates with contacts 16, 17, and a contact 3b which co-operates with a contact 18. Contact 17 is mounted on an annular gear 19 rotatable by a pinion 20 and a motor T.M., whilst contacts 16 and 18 are fixed. In operation with contacts 3a, 16 closed a vibratory feed device (not shown) is started and continues to feed material to the weigh pan until contacts 3a, 17 close and effect cut off. The suspended material then falls into the pan to' complete the charge and so moves indicator 3 beyond contact 17. A relay system (Fig. 5, not shown) then rotates motor T.M. through a fixed angular'displacement in a direction determined by whether or not the final position of indicator 3 closes contacts 18, 3b, so adjusting the position of contact 17. The bottom discharge door of the weigh pan is opened when a switch (not shown) is operated by rotation of motor T.M. In a modification (not shown) the feed is effected by a screw or an endless belt, or a scraper conveyer, or a rotary valve controlling gravity feed, and the contacts are replaced by proximity switches. In a further modification (not shown) the contact 17 is fixed, the motor T.M. being used to adjust a compensating spring, or a resistance to vary the rate of feed, or a weight compensator as described in Specification 743,530. Specification 787,975 also is referred to.