Patent GB-277319-A (GB)
Title: Improvements in electric time switches
IPC: G04C23/22
Filed: 1927-08-30
Abstract: 277,319. Landis et Gyr Soc. Anon. Sept. 8, 1926, [Convention date]. Clockwork actuation.-In time switches which operate switch controls by means of pins screwed into a 24-hour dial in such a manner that each pin operates a separate control, two levers are provided to work with the pins, one to prepare the switch control and the other to operate it. The pins 7 - - 9 are screwed into holes 6 in a dial 2 rotated by the clockwork and co-operate with levers 14 and 16, 16<1> rotatably on a shaft 12 and held by springs 15, 17 respectively against a stop 13. As can be seen in Fig. 3, the pin 7 engages the lever 14, the pin 8 engages the lever 14 and the part 16 of the lever 16, 16<1>, and the pin 9 engages all three. The levers have surfaces 14<1>, 16<11>, 16<111> and the lever 16, 16<1> has a stop 24 on which rests a lever 19 pivoted to the lever 14 and carrying three fingers 20 - - 22 which are adapted to engage the ends of push rods 32. An insulating disc 25 is supported on .one side on a spike 26 and on the other side on a socket 28 by means of a two-part shaft 27, 27<1> forming a universal joint at 31 and urged by a spring into a tipped position. Aligned with two of the push rods 32 are terminals mounted on springs 36, 37 which operate, respectively springs 39, 41. In operation, assuming that the longest pin 9 is engaging levers 14, 16, 16', the pin first engages the lever 14 to withdraw the rod 19, and the fingers which had previously operated the control is removed from the corresponding rod 32. The pin then engages the surfaces of lever 16, 16<1> and so causes the lever 19 to assume the lowest position in which the finger 21 comes opposite its push rod. The pin then leaves the lever 14 which is at once raised against stop 13 by spring 15 whereupon the lever 19 pushes the rod 32, tips the disc 25, and so connects the springs 36, 39 and makes a circuit. When the pin disengages itself from the lever 16, 16<1>, the latter and lever 19 remain in this position due to the spring 15 which is stronger than the spring 17, but when the next pin engages the lever 14, the spring 15 restores the lever 19 to its highest position. As however the pin engages the surfaces 16<11>, the lever 16, 16' is depressed into the intermediate position where the finger 22 comes opposite the corresponding rod 32, subsequent movement of the disc 25 disconnecting contacts 36, 39 and breaking the circuit made by the pin 9. The shortest pin 7 resets the lever 19 in its highest position and when the lever 14 is freed (the lever 16, 16<1> not having been engaged at all by this pin), the disc 25 is tipped by the finger 20 into the position where springs 37, 41 are connected together. Such a time-switch can be employed for a triple-tariff clock, the contacts operating the relay of a counting mechanism, but it would be possible to provide for more than their push rods and consequently more contacts. In the modification shown in Fig. 6, a bolt 43 carries levers 45, 46, corresponding to 14 and 16, 16<1>, which rest on a bolt 44 and have surfaces 47 - - 49. The lever 45 is bent into a U-shaped form and the rear branch carries a blade 50 connected with the. lever 46 by a link 51 and spring 54. The blade 50 is tilted to one side or the other, or allowed to remain in the position shown, according to which pin engages the lever 45, 46. When tilted to either side. it engages one or other of two surfaces 57, 58 on a rocking lever and so rocks the latter to connect up one of two pairs of contacts 60, 62, or 61, 63, the proper rocking movement being effected by top and bottom inclined surfaces and an intermediate recess in a block 65 in a blade spring 66, with which surfaces and recess the end 64 of the lever cooperates. In another form, the surfaces on the lever 14 - - 16<1> could be arranged to lie in a plane parallel to that of the dial, the pins being then of equal length, but arranged in different circular paths.