Patent GB-123155-A (GB)
Title: Improvements in Electric Master and Secondary Clocks.
Inventor: ANDERSEN POUL PETER
IPC: G04C3/02
Filed: 1918-02-12
Abstract: 123,155. Andersen, P. P. Feb. 12, 1918. Electric clocks.-Relates both to a master and secondary clock. The crutch 4, Fig. 1, oscillating with the pendulum-rod 1 in front of it, has a lateral pin 6 ending in front of the pendulum-rod. A plate with central ear is supported in front of the pendulum-rod by two pillars, and between this and a cock thereon is a ratchet-wheel 8. A pawl 7 at the end of the crutch-pin aforementioned being guided by a pin 9 on the plate drives the ratchet-wheel and therewith an arm with pin 11. A detent 10 on the ear of the plate prevents reversal. Under a small cock on the plate is pivoted a lever 13 ending in a fork 15 to balance which the arbor of the lever is provided with an arm 14 carrying a counterpoise 22. Once per revolution of the ratchet-wheel the arm with pin 11 tips the lever 13 by wiping a spur 12 and the fork dips into two cups 18, 19 of mercury. This action temporarily completes the circuit of an electro-magnet 23. The armature B of the electro-magnet is connected by a rod 24 to the root of a lever 26, Fig. 4, which carries by the joint D a foot having three toes 29, 30, 31, the last of which is flexible. Almost in the plane of this foot is a rocking arm 33 (shown separately in Fig. 6) which is furnished with a pin 41 and a stud 49 and is terminated by a knife edge 38. The lever 26 is provided with a hook 44 and a spur 48. Arms 43 and 40 jointed to the pendulum terminate respectively in a spur 42 and a notched finger 39. Normally the lever 26 and its attachments and the rocking arm 33 are in the positions shown by dotted lines, the last resting against a stop 47. The notched finger 39 then travels clear of the end of the rocking arm, and the second arm 43 of the pendulum is clear of the toe 29. On excitation of the electro-magnet, the lever 26 is pulled into the position shown in full lines and is locked by the toe 30 engaging 'behind a stop 34, to which it is depressed when thei toe 31 strikes a plate 35. At the same time, the hook 44 raises the rocking arm 33 by the stud 49 When the pendulum makes the next swing to the right, the notched finger rides on the top of the rocking arm 33, and the spur 42 of the arm 43 mounts on the pin 41 so as to guide the arm over the toe 29 if the swing is still ample. On return to the left, the rocking arm 33 is dragged to the dotted position and a spur 36 at its root acts on the toe 29. The toe 30 is accordingly freed from the stop 34 and the lever 26 falls into the position shown in dotted lines. The arm 43 having dropped off the pin 41, if the swing to the right has been a short one its end is in the path of the toe 29 and thereby receives a thrust which re-energizes the pendulum. Fig. 2 shows the indicator driven by the electro-magnet 23, similar indicators constituting secondary clocks. The armature B having a foot 66 which bears on a lever 62 pivoted at 64, its momentary attraction allows the lever to be tilted by a counterweight 65 so that a pawl 61 at the end takes up another tooth of the minute wheel 59. On the armature falling, the minute wheel is advanced a tooth, the lever being provided with a terminal spur 71 which prevents overdriving. Reversal is prevented by a detent 73 with branch 72. To free the wheels for setting the hands, a hand-lever 68 on an axis 67 is operated to lift the actuating lever and therewith the pawls out of action. The relative hang of the pendulum is indicated by the amplitude scale 74, which is hinged at 76 to the case or frame and has a median hole 75 to take the tip of the pointer when the pendulum is at rest.