rate of charge in amperes corresponding to car speed in m. p. h. with the ordinary gear ratios and wheel sizes. This curve illustrates a sudden rise in current which starts at a speed of about 12 m. p. h. and which reaches its full value of 10 amperes before the speed is increased over 13 miles per M. P. H. From this point on the generator delivers a current having a value of 10 amperes regardless of engine or car speed. The construction of the unit is clearly shown at Fig. 228. The yoke and field winding assembly shows clearly the hexagon yoke Fig. 228.-Views Showing Construction of Simms-Huff Motor-Generator. which makes it easy to mount the device on the engine and at the same time gives a maximum field strength with economy in space and weight. The armature is an iron clad drum winding and is perfectly balanced. The complete unit with the cover removed from the end to permit of ready inspection of commutator and brushes is also outlined. The wiring diagram at Fig. 229 shows the application of the complete system to the Maxwell car while the method of attaching the generator to the engine is clearly depicted at Fig. 230. Fig. 229.-Complete Wiring Diagram of Simms-Huff Starting and Lighting System Used on Maxwell Automobiles. The unit is connected to the gas engine through a gear reduction in the conventional manner. The starting is accomplished by depressing a starter pedal which provides an interlock between the starting switch and the gear reduction. When contact is made at the starting switch the current flows through the armature and field windings, these drawing approximately 40 amperes from the storage battery to start a 4 cylinder car of 30 H. P. The cranking speed depends upon the ratio of gear reduction and condition of the motor. The starting switch construction is bolted to the left side of the transmission case and the interior arrangement Fig. 230.-How the Simms-Huff Motor-Generator is Installed on the Maxwell Engine. is such as to automatically connect the two halves of the storage battery in series when starting which means a current of 12 volts, or in parallel when generating, which means a charging current of 6 volts. As applied to the Maxwell engine the machine is geared to the flywheel by a sliding pinion when starting and is driven by the fan belt from the front end when generating. In common with all systems involving the use of the generator and storage battery together and not having the non-stalling feature, it is essential to provide some means of preventing the bat ! |