GB190702417A - Improvements in and connected with Electric Switches, for use with Internal Combustion Engines. - Google Patents

Abstract

2417. Chambers, J. H., and Bennett, P. F. B. Jan. 31. Switches. - In electric ignition apparatus of i n t ernal-combustion engines arranged to be supplied from two sources, i.e. with accumulator and coil and magneto current, a switch is provided which enables either source to be used separately, o r both together. The construction of this switch is described in Specification No. 2417A, A.D. 1907, and consists essentially of a rotating-arm adapted to make contact between pairs of terminal studs and with one U-shaped dummy terminal. The invention consists in the arrangement of the terminals and of the connexions to the several pieces of the ignition apparatus. Fig. 3 shows a diagram of these connexions, the terminals of the switch being represented by a, b, c, d. The contact-roller f rotates about a pivot k, being always connected thereto ; the pivot k is connected to the contact a by a metal strip e. The terminal a is connected to the common wire l of both systems of ignition, and to this wire are connected one low-tension magneto lead, the magneto - circuit 'contact - breaker q, and the accumulator - circuit contact - breaker p. The magneto m may have its armature short-circuited by a lead r connected to the terminal b. The magneto secondary s is connected to its sparking- plug. The primary o of the induction coil, the secondary t of which is connected to another sparking-plug, is connected between the contactbreaker p and the battery n, the other terminal of which is connected to the contact c. The action is as follows : the switch is in the 'off' position when the roller f is between a and b, the low-tension winding of the magneto armature is then shortcircuited and no sparking occurs at the plug, while the accumulator circuit is open. The switch is in the "accumulator" position when the roller is between b and c; the accumulator circuit is then closed while the magneto armature is still short-circuited. For the "double position, the roller is placed between c and d; the accumulator circuit is then closed simultaneously with the opening of the short circuit on the magneto armature, so that both plugs are free to spark. For the " magneto " position, the roller f rests on the contact d; the accumulator circuit is then broken; and the magneto is free to produce a spark.