GB725926A - Dynamic weigher with electronic counter - Google Patents

Abstract

725,926. Weighing apparatus. TOLEDO SCALE CO. Nov. 11, 1953, No. 31201/53. Class 143. [Also in Group XL (b)] A lever is acted upon by a load to be weighed and a spring in opposition, and allowed to make one complete oscillation from a position of disequilibrium, electric pulses being generated for each equal increment of movement of the lever, the pulses being. counted electronically to indicate the weight of the load. As shown in Fig. 1, the load is placed on plate 1 on a spider 2 constrained to vertical movement by arms 3, 4 attached by horizontal and vertical leaf-springs 6, 7 to the spider 2 and standard 5; a projection 8 supports a spring 9 anchored to arm 4 to oppose the downward thrust of the load; arc arm 24 on spider 2 is connected by a flexible strip 22 to one end of lever 17 pivoted by horizontal and vertical leaf springs 19, 20; lever 17 carries a slotted shutter 32, Fig. V, which can move between a light source 38 and photoelectric cell 40 to generate pulses. To make a weighing, switch 46, Fig. VI, is closed to start motor 43 which makes a holding circuit for itself over cam-operated contacts 51; cam 50 then closes contacts 52 to produce a zero-setting pulse for the electronic counter 42 and to energize relay 36 to release a catch 31, thus releasing the lever 17, Fig. I, and spider 2 from a position of disequilibrium; during the subsequent movement as spider 2 moves downwardly, the shutter 32 moves to generate pulses which are counted in the electronic counter 42; towards the end of one complete oscillation the cam 50 breaks contacts 52 to release relay 36 so that the catch 31 re-engages lever 17 at the bottom of its swing. In a modification, Fig. VIII (not shown), the spring 9 is arranged to act on the lever 17. In a further modification, Fig. VII, the spider 60 carries the shutter 73 on an arm 74 and is directly acted upon by the stop catch 67. In another modification, Fig. IX, the load is applied to the far end of member 100 against a spring 106 through a tape 110 wound round a shaft 104 carrying arms 113, 127; arm 113 carries a slotted shutter 114 for generating the pulses, and arm 127 carries a stop 128 released when cam 129 rotates clockwise and re-engaged when the cam has made one complete revolution which is timed to coincide with one complete oscillation of arm 127. Subsidiary cams driven from motor 137 make contacts for setting the electronic counter to zero and for stopping the motor 137 at the end of one rotation of cam 129. Adjustments. In Fig. I the anchorages of the spring 19 are adjustable along the arms 8, 4 to accommodate widely differing loads, and the equilibrium position of the spider 2 is adjustable by screw and nut 13 on the anchorage on arm 8. In Fig. IX the effective length of the spring 106 is variable by a collar 111 forming part of the support rod 107, and nuts 112 permit the equilibrium position to be adjusted. Specification 425,229 is referred to.