GB271782A - Improvements in weighing scales - Google Patents

Abstract

271,782. Hamblin, F. B. Feb. 14,1927. Indicating, optical devices for; index hands and pointers. - A weighting-scale comprises a screen divided into three zones, one zone to receive a projected image of the weight graduations and the other two zones being distinctly marked, for example by vari-coloured glass, to form over and under weight zones within which indications are displayed by devices co-ordinated with the weight graduations. Means are provided for limiting the extent of movement of the weighing mechanism. The scale beam 2 Fig. 1, is coupled as usual to a pendulum lever 7 carrying an adjustable chart 12, the weight graduations on which are projected by a known lens system on to a ground glass screen, Fig. 2. Two distinctive zones 29, 30 of vari-coloured glass, for over and under weight respectively are provided adjacent the image-receiving zone 28. An adjustable indicating pointer 33 carrying two discs 34, 35 is secured behind the screen. The chart 12 is provided, at predetermined points, with apertures 37, 38, Fig. 4, through which beams of light pass and are projected on to the screen. These beams are masked by the discs 34, 35 when a certain predetermined weight is on the scale, but over or under this weight the beams throw a ray over or under the discs 34, 35 and illuminate a portion of the overweight or underweight zone. The movement of the weighing mechanism may be limited by means of adjustable screw stops 19, 23, Fig. 1, arranged to engage an abutment 22 on the scale beam.