Patent ID: 9085904
Filing Date: 2015-07-21
Classification: E04F,E04G,F03D,Y02E

Abstract:
1. A first fabricated stair tower module, said first fabricated stair tower module comprising: a. At least one assembled stair comprising; b. At least one central support member configured both to receive and be centrally located to a plurality of stair treads, said central support member being generally vertically oriented; c. A first, a second, a third and a fourth vertical corner support member, each corner support member being disposed vertically, all the corner support members surrounding the central support member; d. At least four outer stair stringers, the first outer stringer being connected at one end to the first vertical support member, and at the other end to the second vertical support member, the second outer stringer being connected at one end to the second vertical support member, and at the other end to the third vertical support member, the third outer stringer being connected at one end to the third vertical support member, and at the other end to the fourth vertical support member, and the fourth outer stringer being connected at one end to the fourth vertical support member, and at the other end to the first vertical support member, each of the outer stringers configured to cooperate with a plurality of stair treads, each of the outer stringers disposed at right angles relative to every other outer stringer when viewed from the top orthogonal plane; e. A plurality of stair treads, each stair tread being supported at one end by the central support member and at the other end by one of the four outer stair stringers; f. Each stair tread being oriented relative to the central support member and to every other tread to comprise steps that rise in spiral pattern; and g. Each stair tread configured such that no stair tread extends beyond the outer stringer supporting said stair tread.