IV- Patent Search

Before we started to work on our project and think of our major parts in that project we Google it on the internet and we found a website that’s contain a patent search, we had gone through www.freepatensonline.com , www.patentstorm.us , www.patents.com and after spending some time on it and with help of our professor Emad Tanbour we got two different patent one of them is most similar to our topic which is spiral escalator. And we rewrite the abstract for those patent searches. (Wheeler, G. A., "Elevator," U. S. Patent 479864, Aug. 2, 1892.)

1. SPIRAL ESCALTOR: United States Patent number 5,158,167
2. Nakatani: United States Patent number 5,165,513

And we will write a small abstract on each of the parent and a brief background and a summary of the invention.

1. SPIRAL ESCALTOR:

   A spiral escalator includes a plurality of stairs which are moved along a closed path of travel with the stairs collectively defining generally upwardly and downwardly moving spiral staircases bridged by upper and lower generally horizontally moving stair platforms. A generally vertical spindle is associated with each upwardly and downwardly moving spiral staircase. A male rod and female channel functions as coupling and uncoupling mechanisms for (a) coupling each stair relative to each spindle by relative vertical movement there between during transition movement from the upper horizontally moving stair platform to the downwardly moving spiral staircase and from the lower horizontally moving stair platform to said upwardly moving spiral staircase, and for (b) uncoupling each stair relative to each spindle by relative vertical movement there between during transition movement from the upwardly moving spiral staircase to the upper horizontally moving stair platform and from the downwardly moving spiral staircase to the lower horizontally moving stair platform. (Wheeler, G. A., "Elevator," U. S. Patent 479864, Aug. 2, 1892.)