Patent GB-190422630-A (GB)
Title: Improvements in or connected with Automatic Weighing Machines.
Inventor: PROKOFIEW GEORGE
Filed: 1904-10-20
Granted: 1905-08-24
Abstract: 22,630. Prokofiew, G. Oct. 20. Automatic-feed weighers; feeding-devices.-Relates to improvements on the inventions described in Specifications No. 8880, A.D. 1902, No. 7515, A.D. 1903, and No. 216, A.D. 1904. The alteration of feed is brought about by a change in the speed of the cylindrical sieve d<6>. The sieve shaft b is driven at the commencement of an operation by the pulleys b<2>, p<2> and belt p<2*>, the pulley b<3> through its inferior speed being over-ridden by a sort of free-wheel action. A shaft q, in the same horizontal plane as the shaft b, is driven by toothed gearing therefrom, and causes a nut q<8> to traverse the screw q<7> towards the right, until a flange q<8*> on the nut engages one end 0<2> of a double-forked pivoted lever, thereby causing the other end to separate a spring-pressed clutch-member from its other member, attached to the pulley b<2>. The shaft b is then driven at a reduced speed by the pulley b<3>. Before the completion of the traverse of the nut, a forked finger q<9> encounters a projection r<2> on the slidable shaft r, and the forked finger r' is operated to disengage one end q<3> of the double clutch q<2> from the clutch q<1*>, and to engage the other end q<4> with the clutch part q<5*>. A tumbler r<5> ensures proper engagement. The clutch shaft q<5>, which is continually driven by the grooved pulley q<6>, rotates the screw in a reverse direction to its former motion and the nut travels towards the left. By means of the finger q<9>, projection r<3>, shaft r, finger r<1>, and clutch q<2>, the direction of rotation of the shaft is again reversed at about the time the weighing is completed. The cam-wheel i commences to turn, and a cam i<3> on the wheel depresses a rod n and thereby withdraws a detent s<3> from engagement with the doubleforked pivoted lever above mentioned, this engagement having been brought about when the nut travelled towards the right. The clutch members b<*>, b<1*> then engage by the action of a spring, and the high speed is resumed. At the first motion of the cam-wheel i, a cam i<5> thereon operates a lever t, and the latter separates clutch members to prevent rotation of the shaft b and the sieve, when the feed is cut off by the shutter e. The brush for the sieve is made cylindrical in shape and adjustable. To lessen the impact of the bell-crank lever j<1> on the swinging support l, a stop, attached to some moving part of the mechanism such as the rod r, receives the first impact of the lever and is withdrawn from its path at the required time. For coarse granular material, the sieve is made up of longitudinally-arranged bars. For very fine material, the brush is replaced by a drum, which has a notch just beyond the outlet to the hopper to retain any material carried beyond the outlet. In front of the notch, the drum nearly touches the sieve. For weighing tea and like material, a modified form of machine is described. The rotating sieve and its parts are dispensed with, and the material is fed by a belt from the main hopper to a second hopper, which is closed by a shutter, carried by an arm on a pivoted frame. The belt is driven from the main shaft b, and which transmits to it the varying speed obtained as described above. An adjustable belt is used for cleaning the belt. When the weighing is complete, the rotation of the cam-wheels brings a pin against a piece attached to the detent, freeing the latter from the spring-pressed shutter, which closes. To swing the shutter clear of the hopper, a pin on the camwheel engages with a projection on the pivoted arm supporting the shutter. The valve of the weighing-bucket is opened by a swinging arm.