GB296181A - Improvements in or connected with electrical re-set driving devices for clocks and other mechanism - Google Patents

Abstract

296,181. Mercer, T., and Mercer, F., (trading as Mercer, T. & F.). July 27, 1927. Electric clocks.-In a master clock including a pendulum a and a gravity arm e which reenergizes the pendulum and closes a secondary clock circuit u, the gravity arm is re-set by an electromagnet m, the action of which is delayed. A pawl b on the pendulum drives a count wheel c having a deep notch d. When the pawl reaches this notch it moves an arm h pivoted at i to release a hook j on the gravity arm e (pivoted at f) which falls and, through its roller k, gives an impulse to a pallet l on the pendulum. At the same time an extension y on the gravity arm closes contacts x<1>, y<1> to complete a circuit through battery t, secondary clocks v, extension q (also on the gravity arm), y<1>, x<1>, auxiliary magnet w. through the frame to m<1>, winding of reset magnet m and line u. The action of the magnet w and spring w<1> keep the armature n of magnet m unattracted in spite of the winding m being energized. As the gravity arm continues to sink the arm y is flexed and contact r closes, short circuiting the auxiliary magnet w. Magnet m now attracts its armature and resets the gravity lever, which thereupon opens the circuit u. In a modification the auxiliary magnet is dispensed with and the circuit u is tapped off the battery t.