US 11,753,829 B2
Telescopic staircase system and uses thereof
David Charette, Sherbrooke (CA)
Assigned to METALTECH-OMEGA INC., Laval (CA)
Appl. No. 17/44,180
Filed by Davibois inc., Windsor (CA)
PCT Filed Jun. 12, 2019, PCT No. PCT/CA2019/050832
§ 371(c)(1), (2) Date Sep. 30, 2020,
PCT Pub. No. WO2019/237199, PCT Pub. Date Dec. 19, 2019.
Claims priority of provisional application 62/683,799, filed on Jun. 12, 2018.
Prior Publication US 2021/0087821 A1, Mar. 25, 2021
Int. Cl. E04F 11/18 (2006.01); E04F 11/025 (2006.01); E04F 11/06 (2006.01); E04F 11/112 (2006.01); E04F 11/02 (2006.01)
CPC E04F 11/068 (2013.01) [E04F 11/112 (2013.01); E04F 11/1863 (2013.01); E04F 11/025 (2013.01); E04F 2011/0209 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A telescopic staircase comprising:
a lateral guard having:
a first portion having a first top rail, a first bottom rail and a first newel, the first newel connecting the first top rail to the first bottom rail; and
a second portion having a second top rail, a second bottom rail and a second newel, the second newel connecting the second top rail to the second bottom rail,
wherein the first bottom rail and the second bottom rail comprise connecting holes, and wherein the first portion is telescopable inside the second portion, the first top rail is telescopable inside the second top rail and the first bottom rail is telescopable inside the second bottom rail, the first bottom rail having a first cross-section smaller than a second cross-section of the second bottom rail; and
a plurality of tread assemblies, each tread assembly comprising a tread plate, each tread assembly being removably and directly attached to one of the first bottom rail or the second bottom rail, each tread assembly further comprising two stringer portions and a pair of support members on each stringer portion, each tread assembly being attached to one of the first bottom rail and the second bottom rail through the connecting holes.