Patent GB-190415155-A (GB)
Title: A New or Improved Automatic Electrical Balance.
Inventor: DWORZYNSKI WINCENTY
Filed: 1904-07-06
Granted: 1904-12-08
Abstract: 15,155. Dworzynski, W. July 6. Electric weighing - apparatus; steelyard apparatus; printing-devices; weights, methods of using. -The sliding weight of a weighing-apparatus is adjusted automatically along a lever or steelyard by electrical means until equilibrium is attained. The weight of the body to be weighed is then printed upon a paper strip. The motor which moves the weight is actuated in one or other direction according as a contact carried at the end of the lever engages with the upper or lower of two fixed contacts, the motor always tending to restore equilibrium. The Figures show apparatus for weighing railway wagons. The platform levers are connected to the end 34 of a lever 11 mounted on a casing 1 supported by pillars 2 upon a platform 3, which can be adjusted laterally by a screw 6 in a grooved base provided with levelling-screws 8. The lever 11 is mounted in knife-edge bearings 16, 13 carried by a bracket 14, adjustable on a rail 15 so as to vary the point of support of the lever 11. Links 18 connect the end of the lever 11 to one end of a lever 9 supported by knife-edges 19 in brackets 20 adjustable by means of a screw 25 on a support 21. The knifeedges 19 are formed on a sleeve secured adjustably on the lever 9 by nuts mounted on a screwed portion of the lever. A contact 35 on one end of the lever 9 is adapted to engage with stationary contacts 37, 41, thereby energizing respectively relays 38, 42, arranged to connect a battery in the same direction through the field 27, but in opposite directions through the armature 40, of an electromotor carried by a bent portion of the lever 9. The lever 9 is balanced by a small adjustable weight 33. The axle of the motor armature is connected through a spring 31 or other flexible coupling to a screw 28 mounted in bearings on the lever 9. A weight 10, arranged to travel on the lever 9, is provided with a nut 30 which embraces the screw 28, so that the rotation of the motor causes the weight to move longitudinally until equilibrium is reached. The lever 9 is provided with a scale. By sliding the bearings of the lever 11 longitudinally, the value of a division on the scale can be altered. The motor is prevented from over-running the position of equilibrium of the lever 9 by a brake shown in Fig. 9, and comprising electromagnets 47 arranged in series with the contact 35, and acting on pivoted armatures 46 caused by a spring 44 to retard a disc 43 on the motor shaft when the current through the contact 35 is interrupted. Other means for preventing over-running of the motor may be used. The weight indicated on the scale is printed by means of a plate 50 formed on its upper surface with reversed figures in relief, as shown in Fig. 10, and traversed upon rollers 49 carried by a fixed plate by ears 51 having vertical slots which engage a cross-pin on the nut 30. A strip of paper 60, Fig. 11, is drawn from suitable rollers across the plate 50 and under a rubber pad 57 secured by rods 56 to the armatures 55 of an electromagnet. A spring 58 normally holds the pad in a raised position. The electromagnet is actuated so as to depress the pad by a switch 63, in the circuit of which is arranged a gap which is held open against the action of a spring by an electromagnet arranged in the main circuit, so that the pad 57 cannot be depressed until equilibrium is attained. The pad may be depressed automatically when the contact 35 is disengaged. Fig. 15 shows an arrangement for momentarily depressing the pad, in which a plate 70 carries a key 73, 85, normally held open by a spring 83, and an arm 72 to which is pivoted a rod 81 drawn by a spring 82 against an arm 74 on the key 73, and normally engaging a lug on a lever 75 pivoted in a post 71. When the platform of the machine is loaded, the key 73 is depressed. At the position of equilibrium, current flows from a wire 88 through the electromagnet, the post 71, lever 75, arms 81, 74, and the key 73, 85 to a conductor 89. The armatures 55 are depressed, the cross-bar engaging and releasing the lever 75 so as to open the circuit. A switch 66, Fig. 2, arranged in the battery circuit enables the circuit to be opened when the machine is not in use. A number of spaced horizontal lines 62, Fig. 11, drawn on each side of a central line along the paper strip, subdivide the divisions of the plate 50 and enable more accurate readings to be taken. In the printing shown in Fig. 11, the central line 61 indicates the weight on the platform. The weight 10 may be dispensed with, and the motor made movable along the lever 9 by its armature engaging a fixed screw 28. The weight may consist of a carriage mounted on rails and provided with an electromotor to which current is supplied in a manner similar to that of tramcars. The electromotor may be replaced by any suitable arrangement of electromagnets or solenoids. In the latter case, the solenoids are connected respectively to contacts arranged on the end of the lever 9 and adapted to engage a single fixed contact.