Patent GB-191228748-A (GB)
Title: Improvements in Machines for Generating Electric Current for Dual Purposes such as Ignition and Illumination.
Inventor: HOLLISTER FREDERICK LOUIS
IPC: H02K16/00
Filed: 1912-12-13
Granted: 1913-12-15
Abstract: 28,748. Hollister, F. L. Dec. 13. Magneto-electric machines; rotary machines; dynamos, regulating; exciting. - A magneto and a dynamo for generating two currents, for example for the ignition of an internal-combustion engine used on a motor-vehicle and for the lighting of the vehicle, are assembled together in such a manner that they can be detached or be adjusted relatively to one another. According to one construction, the housing a, Fig. 1, of the combined machine carries at its lowest part the magneto unit, which comprises the armature b mounted on the spindle c and an horizontally - arranged horseshoe magnet d having the pole-shoes d‹. The dynamo unit comprises a field magnet f and an armature j mounted upon a shaft i, which is driven from the spindle c by a chain or other flexible drive n. Springs m surrounding two pairs of guide pillars l tend to keep the dynamo and magneto units apart. The permanent magnet of the magneto may consist of a pair of inclined magnets, Fig. 4, leaving an opening e' at the crown for the passage of the spindle c. In a modification, the magneto has the usual vertical magnets, and the field magnet of the dynamo is constituted by combined electromagnets and permanent magnets. To assist lowspeed generation, the permanent magnets are not in contact with the pole-pieces along their whole length. The dynamo is preferably of the constant-voltage type, and regulation may be effected in accordance with the speed of the dynamo by means of an oscillating graduated magnetic sleeve acting as a variable magnetic shunt to the field magnet. Alternatively, regulation may be effected by utilizing a portion of the wave form of the magneto armature current either as a demagnetizing or magnetizing agent with separate field-magnets or demagnetizing coils. Fig. 11 shows a portion of the wave form, the shaded portions q at the peaks indicating the portions used for sparking purposes, the remainder being used for regulating purposes, and Fig. 12 shows the demagnetizing or magnetizing coil p<1> excited from the magneto (not shown) with unidirectional current by means of a commutator r; the method of regulation may be combined with a method utilizing resistances having negative temperature-coefficients. Fig. 8 shows a construction in which the magneto and dynamo units can slide relatively to one another and can be adjusted by means of right and left handed screws u. The sparking obtained at the advance and retard position of the timing lever may be equalized by fitting the fieldmagnet with adjustable pole-shoes which are so connected with the timing-lever, for example, by pinions and toothed segments that a given angular movement of the lever imparts a greater angular movement to the pole-shoes. Friction gearing may be used. The Provisional Specification describes also a further modification in which the dynamo armature is of the ring type with the magneto armature located within it; both the armatures are rotated together, or the dynamo armature and the magneto permanent magnet are rotated as one.