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the coils, a knife switch controlled by the clutch pedal and a push button located on the steering wheel. All changes of gears are controlled by the knife switch and the push buttons on steering wheel merely arranges the circuit for the particular speed desired. A glance at the cut shows that the clutch pedal moves through a link during the first part of its motion and during the remainder
picks up the link and carries it along with it. Thus the first movement is the regular operation of the clutch, but a continued
operation of the clutch COMMON
lever actuates the knife BUS
Current flows from the battery through the solenoid coil and
pulls a plunger against HORN
a magnet with a force which is given as 40 to 100 pounds.
This energy is transmitted 33
through an arm to the 3rd
gear-shifting fork and
gear in exactly the COILS
same manner as if the gears were operated with hand lever.
The plungers are norBATTERY
mally in neutral position. When the button is pressed on
the control member, Fig. 281. — Wiring Diagram Showing the Method of Connecting the Vulcan Electric
current passes through Gear Shift with the Battery and Control
the coil around one of Switch.
the plungers, drawing
it against the magnet. It is said that the current required to make the shift is about 17 amperes, and it is claimed, further, that three hundred speed changes may be made with less current consumption than is required in starting the motor with an electric starting device.
Fig. 282.—Simplified Diagrams Showing How Current Passed through the
Solenoid Will Draw in an Iron Core Piece Which May Be Made to
An advantage claimed for this electric gearshift is that the gears cannot be stripped, for the reason that the clutch must be disengaged before a shift can be made and the gears are always in neutral before the coils can accomplish the change. Furthermore, no two speeds can be utilized at the same time, because each speed is governed independently of the others, and an interlocking device prevents the operator from using any two buttons at one time, even if he should make a mistake or be careless.
The box which contains the switches and solenoid coils shown at Fig. 283 is mounted at the side of the gear box, and it is said that the device adds only 46 pounds to the weight of the chassis. On the S. G. V. car the control buttons are mounted in a neat
aluminum box on the steering wheel, one for each speed, and one for a neutral member. In operation the system is very simple. If, for instance, the fourth speed button is pushed down and the clutch is thrown out and then re-engaged, the car will remain in fourth speed. When driving in traffic on the third speed the driver may set the second speed button and by depressing the clutch pedal fully will automatically shift into second speed. In a similar manner all other changes may be made. The driver need not lift his hand from the wheel in order to accomplish any change in the
gears. Those who have witnessed the operation of this device state that the system is quiet, the only noise being a slight click as the gears engage when changed. This system is also used on the Haynes 1914 automobiles and several other types.
Hartford Electric Brake.—The brake is compact and light, weighing only about 35 pounds. It consists of a small type of the Hartford reversible electric motor with a worm and worm wheel secured to a drum. To this drum is attached a steel cable, the other end of which is fastened to the brake equalizer. (See Fig. 284.)
The most important part of the Hartford brake is the patented controller which is placed within easy reach of the driver's hand, as shown in the illustration. By this new device any desired nicety in the application of the braking effect is obtainable by purely electrical means.
Actual demonstration is said to have shown it to be possible to control a 60 horsepower car weighing over 4,000 pounds by the mere pressure of one finger on the operating lever.
A two point control is obtained with this switch, the first point giving enough braking power for regular service, and the second for an emergency stop. Pushing the switch back to its original position immediately disengages the brake. The idea of the whole system may be summed up in a few words by saying that the manual labor usually connected with brake operation is replaced by the work of a high speed, series wound electric motor which may be fed with current from a storage battery or either 6, 12 or 24 volts (for automobile purposes, or higher voltage, if desired, for other purposes). The armature shaft of this motor carries a worm which drives a worm gear at a reduction of 100 to 1. This worm gear in turn operates a drum through an internal gear at a reduction of 4 to 1, thus giving a total reduction of 400 to 1. On the drum is wound a steel brake-pulling cable which transmits the pull of the motor to the brake mechanism.
When running idle the motor is capable of a speed of 10,000 r.p.m., and when under load it can exert a pull of 1,000 pounds at a speed corresponding to a quick application of the hand emergency brake. After the pull exerted on the cable has attained a value of 1,000 pounds, a slipping clutch prevents any further increase, and a ratchet prevents the brake from slipping off. The powerful pull exerted on the brake cable permits of operating the brakes in oil. It is stated that, the current flow in applying the brake amounts to 40 amperes for two-fifths of a second (presumably for a voltage of 6). The Hartford brake replaces the emergency set and is used constantly in service, the foot brake re
Fig. 284.—How the Hartford Electric Brake Works.
maining as originally installed, for use if wanted. One advantageous feature of the Hartford brake is that it can be easily attached to any existing car, provided it is equipped with a storage battery.
Electric Air Heater.—Nearly every starting difficulty with automobile motors is due to poor carburetion arising from the low temperature of the air and the fuel. It must not be forgotten that