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UNION COMMERCE BLDG.
ESTH EUCLID
An intermediate stop on a Carveyor route allows people to board and exit Carveyor cars from a single, moving loading ramp. The ramp moves at the same speed as the cars as they pass through the station
during rush hours, everyone would have a seat.
As the cars proceed alongside the loading belt at a synchronized speed, the passenger steps from the moving loading platform belt into the car. The effect is the same as if he were passing from one room to another since the car floor overlaps the loading belt slightly and is beveled.
A continuous row of cars is always moving through the station and is able to handle all those who enter the load- ing belt. Through the low-speed station area, the cars are back-to-back, so no one can push, fall, or jump in front of oncoming cars.
Beyond the loading-platform belt (length and width of which are govern- ed by desired capacity) the cars pass over a bank of acceleration wheels which gradually step up the speed at any designated acceleration rate. Tran- sit experts feel that a desirable rate of acceleration is 24 mph per sec which is 4 ft. per sec per sec. Once the car acelerates to its designated high speed, it moves onto a main high-speed belt and travels to the next station.
The speed range of the high-speed belt is variable and systems with a high speed of 15 mph have actually been designed. At this speed cars are spaced approximately 70 ft. apart. Long radius horizontal curves along the
Far East BUILDER, March 1971 Page 40
high-speed line are possible without any speed reduction by using roller sections along the curve. Turns up to 180 deg. can be negotiated at properly reduced speeds.
As the cars enter a station area they move from the high-speed belt onto a bed of decelerating wheels which slow the cars down by their braking action to the desired slow speed of the unloading platform belt. The exiting passenger merely steps from the car onto the unloading belt moving at the same speed and walks off the end of the platform belt.
At the point of exit from the car, the effect is the same as stepping from a stopped car onto a stationary plat form since the car carrying belt and the unloading belt are moving at iden- tical speeds and there is no relative motion between them.
Many variations are possible. A system may be of the shuttle or single route type, or of the loop type with cars running only in one direction, or in both directions either above or be low ground.
Acceleration
Accelerating and declerating de- vices are special forms of live con- veyor, consisting of a series of rotated wheels mounted two on a shaft.
Each set of wheels in an accelera
ing conveyor, starting at the low speed end, is driven at a sucessively higher speed than the set preceding it. The shafts are spaced so that a car rests on four sets of wheels at a time. Slippage is not desirable between the solid rub- ber tires and the bottom of the cars, which would be the situation if each of the four shafts were rotating at a different but fixed speed.
Each of the four sets of wheels on which a car is resting must be rotating at the same speed at any moment and yet each set must be trying to turn faster to accelerate the car. In order to achieve this result, each set of wheels is driven through a constant-torque coupling. The torque setting of the couplings is such that any four sets of wheels will apply enough force on a loaded car to accelerate it at the rate of 2% mph per sec. This force is not enough to cause the wheels to slip under the weight of even an empty car.
As the leading edge of a car makes contact with a set of wheels, the wheels slow down due to slippage in the coupling. When the car is fully loaded, the wheels will speed up just enough to be running at their normal speed with no slipping in the coupling at the moment the car leaves it. There- fore, the normal driven speeds of the wheels correspond to the speed of the
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Maximum Capacity
in. Number of Riders per Hour
Passing any Point
in System