latch mechanism 211 212 213 214 215 216 shown in more detail in fig8 and 9 the ascent and descent mechanism 205 206 207 shown in more detail in fig1 guide rollers 202 and a guard ring 230 the guide rollers 202 are mounted on an axle that perforates the profile base 201 of the sliding element they are positioned so as to rotate against that position of the rail that contains the perforations 102 i e the 34 frontal 34 side of the rail and thereby to facilitate movement of the sliding element up and down the rail two pins 203 also perforate the profile 201 and serve as fastening elements for the tubular or solid structure of support for the walkways 300 the handle 204 actuates a worm drive 205 mounted on the profile 201 that cooperates with a crown gear 206 mounted on an axle 207 which is preferably of a non cylindrical shape to avoid the sliding the escalator wheels 208 are mounted on and actuated by the axle 207 the projections of the escalator wheels interact with the regular perforations 102 existing in the frontal side of the rail 100 with which will all move the part of the sliding element 200 and with it the moveable walkway a latch 210 is positioned on the handle 204 this latch comprises a handle 211 which is moveable between a retracted and an extended position under the influence of spring 213 in its retracted position the latch handle 211 is restrained by retainer 212 it may however be released from.