Improvements in Scales or Balances for Laboratory use.

摘要

13,683. Knegt, P. de. June 16. Chemical balances.-The balance beam 1 is pivoted on two points 4 bearing on plane surfaces 5 on the fixed upright 2, and the pans are each supported by a single point 6 bearing on a plane surface 7 connected to the stirrups 34 of the pans. Greater accuracy in weighing is thus obtained. The balance beam is supported when not in use by means of two vertical rods 9 attached by a pin- and-slot connection to caps 25 forked at the top to engage the beam. Arms 8 fixed to the rods 9 lift the bearing-surfaces 7 from the points 6. The pans 3 are supported, when not in use, by plates 13 carried by a cross-bar 22 fixed to the rods 9. The cross-bar 22 rests on a cross-bar 28, which is raised and lowered by a lever 11 carrying a slanting disc 14 on which works the bent arm 15 of a spindle 23 carrying a knob 16. On turning this knob, the lever 11 is actuated and the balance supported in operative or inoperative position.