Re: 53 Cavalier Self-Parker

Posted by 3spdOD On 2012/7/23 11:50:49

This Cavalier was on display yesterday at the show associated with the Pittsburgh Vintage Grand Prix, and I had a good chance to examine the mechanism and talk with the owner.

As shown in one pic, there's a huge hydraulic cylinder (presumably activated by a hydraulic pump as used on convertibles, cars with power windows and hearses with Level-draulic systems, but the hood was closed and I didn't think to ask). Anyway, with the car nosed into the intended parking spot, that cylinder forces the continental spare down to the ground and then lifts the rear end off the ground. (Imagine the angle the Cavalier would be at, by this time, and particularly if the pavement is uneven, in order for both wheels to clear the pavement.) At the same time as the rear is lifted, a complex lever system connected to the mechanism engages a drum into the rear of the right rear tire. That drum connects turns the largest fan belt I've ever seen, which turns 90deg under the corner of the right rear quarter. By putting the car in gear - D or R depending on which way you want the rear end to go - the rear wheel turns the drum, which turns the fan belt, which turns a gear at the other end of the arrangement. That gear is engaged with a much larger gear wheel behind the continental spare, moving it slowly in the direction of the parking space. If anyone's interested in the specs, I'd estimate the drum as 8" diameter, the drive gear at maybe 2", and the driven gear at 14", but at the time I looked at it I wasn't trying to estimate sizes.

I guess on a non-level space, the contact of the spare with the ground keeps the car from lurching forward or backward, but there must be some unwanted movement of that sort in such situations. Also, when non-level left-to-right, I imagine that getting both wheels off the ground might be problematic too. Further, knowing that those bodies are not absolutely rigid, I can imagine that if you opened the door to see how things were when the rear end end was off the ground, the door would at best not close well. I imagine that these may well have been reasons why Packard declined to take the patent.