Patent GB-377728-A (GB)
Title: Improvements in or relating to high tension ignition magnetos
IPC: H02K21/18
Filed: 1931-04-22
Abstract: 377,728. Magnetos; condensers. BERNARD, J., La Jasse, near St. Hilaire de BrÞthmas, Gard, France. April 22, 1931, No. 11944. Convention date, May 19, 1930. [Classes 35 and 38 (ii).] A magneto comprises a horseshoe or U-shaped magnet 3 mounted on a driving shaft 1 parallel with the magnet legs and having pole-shoes 2 outside the legs, the driving connection between the magnet and the shaft being effected at the extremities of the magnet legs, the elasticity or resiliency of which is employed to bind them against a member 4 or 65<1> associated with the shaft to avoid torsional stresses therein. The pole-shoes 2, Fig. 1, are secured to the magnet by a non-magnetic bolt 5 and countersunk nuts 6. The apex of the magnet through which passes the shaft is formed with a recess to receive a pin 8 and the distributer driving pinion 7 which is thus driven directly by the magnet and is held thereagainst by a nut 67 and the shaft. In a modification, Fig. 5, keys 66 with tapered portions 661 bear against inclined faces on portions 70 projecting from the magnet legs so that when nuts 69 are tightened the lugs are pressed against shoulders 65 on a member 65<1> fixed to the shaft. The nut 69 may be disposed between the magnet legs as shown in Fig. 10 which also shows the application to magnets of curved formation. The ends of the magnet legs may be formed with projections or recesses to fit corresponding recesses or projections in the member 651, the nut 67 applying the necessary longitudinal pressure to maintain the parts in register. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following subject-matter. The edges of the armature polepiece, Fig. 2, are flush with the machine housing and the cover 13 bears on elastic packing 15 on the core laminations 16. The core is cylindrical and is assembled from plates of different widths to avoid magnetic shortcircuits between the plate edges. The coil cheeks are each formed with projections, one 17 serving to hold a cover 17a and the other 18 being grooved to carry a condenser 19 on items or bolts 20. The condenser, Fig. 8 (Cancelled), is mounted on an insulating spindle extended on each side by the stems 20 which are provided with nuts 21 for tightening up connecting electrodes 22, a spring or other washer 23 being interposed. At the same time insulating discs 24 seal the end of an insulating cylinder 25. The contact-breaker mechanism is supported on a lug 32, Fig. 9 (Cancelled), integral with the bearing block 26 and comprises a blade 34 rendered rigid over a portion of its length by means of a U-shaped iron piece 35 and adapted to be moved by the cam against a laminated spring 39. Two interrupters may be provided in the magneto primary circuit, or one may control a separate coil ignition circuit. The arm 55 of the distributer, Fig. 1, is electrically connected to the generating coil 12a by means of a conducting stem 53 contacting with a resilient terminal 54 of the coil. The distributer core is held in position by resilient clamps. Where no distributer is employed, connection to the secondary winding is effected as shown in Fig. 16 (Cancelled), where the current sparks across from the tube 63 to the stem 64. Fig. 5 (Cancelled) shows the magneto casing formed with integral lugs 11 for attachment to a casing containing the driving gear and a distributer. The rotary distributer contacts 55, Fig. 24 (Cancelled), may be fitted with claws 69 to prevent loosening and the centre is provided with a hard metal bush 70 and lubricated by a wick. This subject-matter does not appear in the Specification as accepted.