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If you want a clearer picture of how this works, grab the transmission out of your car, stick it on a band saw and slice it in half. (Do this outside though because the oil that falls out gets a bit messy.) If you don't feel like ruining your car, then go over to your local pediatric doctor's office. They almost always have this one toy in the waiting room that has lots of different sized gears you put together on a special table. When you're done assembling the thing you turn the crank at one end and all the gears turn and then something moves at the other end. It's way cool. (I never have enough time to finish putting it all together before the nurse comes. I hate that.) [Note : Helpful tip from Alert Reader Kevin Patrick
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Now we need to figure out how to connect the motor to the gearbox. One common way is to use a large roller type chain drive. (Think of a bicycle chain on steroids) First a metal sprocket - a wheel with teeth around the rim - is put onto the motor shaft. Then a sprocket is attached to the shaft that runs into the gearbox. Finally, a loop of roller chain is wrapped around the two sprockets. Viola! Now, in addition to turning the gears in the gearbox, you can also make neat motorcycle noises when you turn the motor on. Vrooom, vrooommm. (For instructions on how to make the motor noise without actually having a motor, talk to a kid..any kid. They all know how.)
Another way to connect the motor to the gearbox would be to butt the end of the motor shaft up against the end of the gearbox shaft and connect the two with a device called a coupler. Couplers are OK (don't even think of going to *that* place. This is a family newsletter.) but when you use a coupler you add more hardware that could fail. And it's not all that easy to find couplers that are rated for overhead lifting. The third - and safest - way to get those gears turning is called "direct drive". With this method the shaft coming out of the motor is long enough to run completely through the gearbox. So when the motor turns on, there is only the single shaft connecting both the motor and gearbox that's turning. It's a less complex assembly than the other two methods mentioned. Less hardware is used and that means there's less opportunity for something to go wrong or break.
We still have that piece of scenery sitting on the floor waiting to get picked up, right? Not to worry, we're getting closer to a solution.
The cable drum is the last major component needed to get the scenery moving. The drum is a section of large diameter pipe that the lift cable will wind up on and pay out from. It is connected to the gear box in the same manner that the gearbox is connected to the motor. (Forgot already? Back up a paragraph or two) As noted before, the best way is the direct drive method.
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