GB258709A - Improvements in automatic weighing machines - Google Patents

Abstract

258,709. West, R. R. July 28, 1925. Indicating-mechanism. - An automatic weighing-machine has a stationary scale or pointer, a movable pointer or scale operatively connected to the weighing mechanism, and a freely mounted scale or pointer adapted to be maintained in the zero position while the tare weight is being registered and to be moved with the scale or pointer connected to the weighing mechanism to indicate the net weight of the commodity. The indicating spindle c of the machine carries a dial b graduated in a counter-clockwise direction. Outside the dial b is a stationary dial a graduated in the - opposite direction. In front of both dials is a pointer d provided with two indicating points d<3>, d<4> and mounted upon a movable fitting d<1> so as to be capable of assuming a stationary forward detached position as shown in Fig. 3, or a rearward position coupled to the dial b for rotary movement therewith, as shown in Fig. 2. In performing a weighing operation, starting with the mechanism in the zero position shown in Fig. 3, an empty receptacle is placed on the weighing platform and the dial b rotates in a clockwise direction in proportion to the weight, the tare weight being thus indicated upon the dial b by the point d<4>. A press button h<2> is now pressed in so as to assume the position shown in Fig. 2. where it is retained by the entry of a spring g<2> into a groove h<3> in the plunger h of the press button. During the inward movement the pointed end h' of the plunger, acting through a spring d<9>, presses back the fitting d<1> carrying the pointer d until teeth d<5> on the pointer engage grooves on the dial b and thus couple the pointer and dial together. The commodity is now placed in the receptacle and the dial makes a further rotation, carrying with it the pointer d. The net weight is now indicated by the point d' upon the stationary dial a, and the gross weight is indicated upon the dial b at the zero point of the stationary dial a or vice versa. Upon removal of the receptacle the dial and pointer return to zero position and an arm i' on the pointer-fitting knocks back the spring g<2>, thus allowing the button plunger h to return under spring action, and by the engagement of clutch parts h<4>, i<2> to draw the pointer d. forward into its detached position shown in Fig. 3. Mutually-engaging inclines on the plunger-support g and on the pointer fitting ensure positive zeroization of the pointer. If the tare weight of the receptacle is known the pointer d may be set back behind the zero position by hand in readiness for a series of weighings, by rotating the plunger support g the necessary amount by means of a knob g<1>. In a modification the spring d' is arranged within the plunger h. In further modifications. the circular dials are replaced by straight scales or quadrant scales. The pointer mav be stationarv and the inner and outer dials movable. Magnetic means may be used to clutch and declutch the pointer to and from the movable dial.