Tow trailer

Hi people!

So this is my entry to the challenge on designing a tow trailer for the Catfish race car. First and foremost I would like to express that I don't know the terminology used by trailer manufacturers, so I apologize in advance for a possible ill use of some terms.

I designed a trailer whose bed (the part where the car being towed sits, aka the trailer floor) can be lowered to allow the car to drive on and to drive off and can be raised to allow the trailer to actually move.

I didn't use any hydraulic system because that would require some type of motor or engine to be mounted on the trailer which would require an external energy supply (either gas for an IC engine, or a battery or some sort of electrical connection to the towing vehicle), and I believe this would make the final price of the trailer to go up.

So I used a very old and simple mechanism, the screw jack. There is an hexagonal "bolt" to which an electrical portable drill can be mounted and when turned on the motion is transfered to a simple gearbox (speed reducer/torque multiplier) and afterwards to a shaft that makes a long screw rotate. The rotation of this screw is converted to a linear motion of a slider which is connected to a rod which, in turn, is connected to the bed.

But wait, there's more, the bed itself can be attached and detached from the trailer frame by unscrewing 8 nuts. Since the bed has some industrial caster wheels under it, it can be moved around (with the car above it) to position the car in those really tight spots. That will make videos like this a thing of the past: http://www.youtube.com/watch?v=_pqCShijhtc

With the bed detached from the frame you will be able to move the car like in this video: http://www.youtube.com/watch?v=mush3hNbnmY

When you need to tow it again just align the bed with the frame, torque the 8 nuts and you're good to go.

It doesn't even have to be operated with a drill, there can exist a lever to raise and lower the bed by hand.

On the back of the trailer there is a removable piece where the logos and the license plate can be attached. The function of that piece is to increase the stiffness of the back of the trailer while towing a car.

I haven't concerned myself with the "resting support wheel" (the caster wheel that should exist on the front of the trailer, so that when you disconnect the trailer from the car it doesn't tumble) and with the "towing ball" because, well, those are two standard items, you can j...