the centrifugal governor used on the other types illustrated, is shown at D, supplied for direct drive by an extension of the timing gear shaft and for chain drive at E. The dynamo shown at D is provided with gearing to drive a timer distributor for ignition purposes. The current supply is governed by the regulator cut-out (Fig. 202), which performs two duties in the new systems. One of

Ford System.

these is to regulate the dynamo to secure uniform current output, while in the other instance it connects the dynamo into the system only when sufficient current is generated to charge the battery. Current regulation is provided by short circuiting or shunting field resistances or to insert the field resistances into the field circuit. The object of the field resistance is to retard the flow of current in those windings. When the dynamo is at rest the cutout points are opened and the regulator points closed. As the dynamo first speeds up the regulator points remain closed and the field resistance is short

circuited. This permits the dynamo to build up its full field strength. When the proper voltage is reached the cutout points close, permitting current to flow through the series winding to the system. As the dynamo speed increases beyond that necessary for full output, the pull of the shunt winding attracts the regulator armature.

This reduces the pressure at the regulator points and inserts a resistance into the field circuit, this preventing further increase of output. The frequency with which the resistance is put into the circuit is in proportion with the amount of speed variation. The form of battery used with the Gray & Davis system is shown in part section at F, Fig. 201. It does not differ materially in structure from types previously described.

One Unit Ford Systems. When one considers the large number of Ford cars that are in with an electric starting

daily use, and that these are not provided system by the maker, it will be apparent that a fertile field is opened up among Ford users for the sale of starting motors. Practically all Ford systems are of the one unit type, because these constructions are especially well adapted for use at points. where simplicity is essential. The Gray & Davis one unit system is shown installed at Fig. 203, and ready for installation on the motor at Fig. 204. The armature is driven from the engine

Fig. 205.-Wiring Diagram Showing Method of Connecting Parts of Gray & Davis One Unit Ford System.

crankshaft by two chains which provide a double reduction. The machine is so constructed that it is adapted to fit a special bracket that makes it possible to install the device on any Ford motor without structural changes. The wiring diagram shown at Fig. 205 is extremely simple. The six volt storage battery has its positive terminal grounded while the negative terminal

for Ford Cars.

is connected to the motor generator by a heavy wire which must first pass through the starting switch. The circuit is completed by ground connection through the supporting bracket when the starting switch is depressed. There are two terminals on the cutout relay on the top of the motor generator; one of these is marked L, the other B. Terminal L leads to the negative of the storage

battery, being attached to this lead on the battery side of the starting switch. Terminal B leads to the lighting switch. The remaining wires are easily followed, these leading to the various lamps, all of which operate, on the one wire system.

The Genemotor which is shown at Fig. 206 is made by the General Electric Company, and is a single unit operating on twelve volts. It is permanently connected to the engine shaft by a single Morse silent chain, the ratio of reduction being two to one, which provides sufficient torque for starting the motor while at the same time the maximum armature speed is limited to a safe value. The device becomes a generator at a car speed of 12 m. p. h. on the direct drive. The motor generator is about 11 inches long, 7 inches in diameter, and weighs 52 pounds. It

Fig. 207.-Wiring Diagram of Genemotor-Ford Starting and Lighting System.

gives a starting torque of 86 foot pounds at the engine crankshaft, or 43 foot pounds at the armature operating with the 42ampere hour battery supplied with the system. It is mounted. on a pressed steel bracket designed for attachment at the left side of the engine. The bracket rests on the cylinder base bolts and is held rigidly in place by clamping it under the two water

Fig. 208.-Wiring Diagram Showing Parts of Dodge-North East One Unit Starting and Lighting System.