Patent GB-906892-A (GB)
Title: Improved weighing apparatus
IPC: G01G3/04
Filed: 1960-01-26
Abstract: 906,892. Weighing-apparatus. VOGEL, R. C. F., [trading as VOGEL & HALKE]. Jan. 26, 1960 [Jan. 26, 1959; Aug. 17, 1959; Dec. 24, 1959], No. 2878/60. Class 143. In a spring balance comprising a load carrier mounted on parallel springs, movement of the carrier is communicated to a rack-and-pinion actuated indicator by an angle lever which is mounted on a stationary pivot and which has two bearing cups which are connected respectively to the carrier and to the rack, said lever being formed in two relatively adjustable parts. Fig. 1 shows the load carrier 1  mounted on a support 2 carried by the free ends of a pair of parallel leaf springs 3, 4 anchored to a fixed support 5 and in this embodiment the angle lever comprises the lever arms 7 and 9, arm 7 being mounted on the pivot 8 and arm 9 being adjustably movable along a groove in a flange 65 of arm 7, to which it is secured by a nut 26. A coupling 11 connects a bearing cup on arm 9 to a cup 6 carried by the load carrier support 2, and a cup 10 on arm 7 is directly coupled to the indicator rack 12. In Fig. 1, the pivot 8 is adjustably movable to zero the indicator by being mounted at one end of bell-crank lever 19 whose other end is acted on by a zeroing screw 21. In Fig. 3, the pivot 8 of arm 7 is fixed and adjustment of the zeroing screw 32 is made to tilt a lever 30 whose free end is connected to a member 28 on the support 2 by a coil-spring 29. Zeroing then consists in making the spring 29 support the entire tare load. The position of arm 9 with respect to arm 7 is varied by tilting the former about a pivot 43 carried in the latter by means of adjustment screws 44, 45. Fig. 5 (not shown) discloses a construction whereby adjustments of the position of arm 9 on arm 7 by sliding (as in Fig. 1) and by tilting (as in Fig. 3) may both be employed, and which incorporates provision for varying the position of cup 6 on carrier 2 by sliding horizontally.  The weighing springs 3, 4 may be acted on by additional springs whereby the characteristics of the weighing spring may be adjusted. Fig. 8 shows, in plan view, a construction in which the upper spring 3 comprises two spring members 97, 99 attached by rivets 102 to members 96, 101 corresponding to the members 5, 2, respectively, of Figs. 1 and 3. Between the rivet heads and the springs are holding bars 103 under two of which are disposed adjustably positionable additional flat springs 106, 107, and to facilitate the adjustment appropriate rivets 102 are replaced by screws 105, 104. A variety of shapes, and sizes and places of attachment of such springs are given in Figs. 10 and 12 (not reproduced). In Fig. 8, shaft 121, rockably mounted in a support member 119, carries an angle lever comprising arms 123 (Figs. 15 and 17) and 124 (Fig. 18), which arms correspond to the arms 7 and 9, respectively, of Figs. 1 and 3. The arms 123 124 mounted on shaft 121 arespaced apartas  shown by laterally extending bearing bodies 127 and 137 on the members 123, 124, respectively. The divergent gaps between the bodies 127, 137 allow the relative orientation of the members 123, 124 to be adjusted as by screws 144 (Fig. 15) passing through holes such as 130, 131 (Fig. 17) in the bearing bodies. At 157 in Fig. 8 is a spring by which the tare load is supported as described with reference to Fig. 3.  Shocks to the indicating mechanism may be avoided by spring damping the movement of the angle lever and/or its couplings to the bridge carrier and the indicator rack. Fig. 25 shows a means for such damping of the angle lever in which its rack-engaging and load carrier coupling arms 191 and 194, respectively, are relatively rotatable about a common axle against the resistance of a spring 227. Fig. 24 shows a hook 218 to be coupled to arm 194 of Fig. 25 by means of a rod such as 11 in Fig. 1, hook 218 being pivoted to a part 197 attached to the load carrier support 174, tilting about the pivot being resisted by a spring 217. Fig. 21 shows a spring-damped rack comprising the parts 200, 201 of which the former is engaged by the arm 191 (Fig. 25) and the latter carries the rack teeth engaging with the pinion 187 carrying the rotatable indicator. In this construction, springs 203, 204 are the rack return-springs and spring 202 constitutes the damping means.