Curved escalator
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsHiroshi Nakatani, Makoto Tomidokoro, Hiroshi Yoshikawa
Life of this patent
Estimating the term…
Abstract
A curved escalator includes guide tracks for defining a stairway path which includes a constant slope intermediate section, horizontal landing sections, and transient sections smoothly connecting the intermediate section and the landing sections. Each section of differing slope has a differing radius of curvature which when viewed in plan, is inversely proportional to the slope angle, thereby eliminating the need for drive chains to change the distance between the step axles. Turn-around mechanisms that are compact and simple in structure are also disclosed.
Claims5
A curved escalator comprising:
- an inextensible endless belt means;
- a plurality of segment steps of fixed width with an outer end and an inner end attached to said endless belt means;
- means for driving said endless belt means in a loop disposed along a stairway path and means for guiding said belt means about said loop, said stairway path being curved in plan and having an intermediate section that has a predetermined constant slope angle, upper and lower landing sections that have substantially zero slope angle, and transition sections connecting said intermediate section to said upper or lower section that have sloping angles for smooth connection of the sections, said upper and lower horizontal sections being curved with constant radii of curvature about a center of curvature, said intermediate constant slope section being curved with constant radius of curvature about a center of curvature which is smaller than the radii of curvature of said upper and lower horizontal sections, and said upper and lower transition sections having radii of curvature about a center of curvature which gradually vary in accordance with the change in slope angle of said transition section, the center of curvature of the transition sections gradually shifting between the center of curvature of the intermediate constant slope section and the centers of curvature of the upper and lower horizontal sections such that the outer step end travels along a path having a radius related to the slope at the outer end determined by the relationship
- R.sub.1 (.theta..sub.1)=(R.sub.1 (R.sub.1 -R.sub.2) cos .theta..sub.1)/(R.sub.1 cos .theta..sub.1 -R.sub.2 cos .theta..sub.2)
- and the inner step end travels along a path having a path related to the slope at the inner end determined by the relationship
- R.sub.2 (.theta..sub.2)=(R.sub.2 (R.sub.1 -R.sub.2) cos .theta..sub.2)/(R.sub.1 cos .theta..sub.1 -R.sub.2 cos .theta..sub.2)
- where
- R.sub.1 (.theta..sub.1):
- radius of curvature of the outer end at an arbitrary position
- R.sub.2 (.theta..sub.2):
- radius of curvature of the inner end at an arbitrary position
- R.sub.1 :
- radius of curvature of the outer end at the upper and lower landing sections
- R.sub.2 :
- radius of curvature of the inner end at the upper and lower landing sections
- .theta..sub. :
- slope angle of the outer end
- .theta..sub.2 :
- slope angle at the inner end;
- whereby the angular speed of the outer and inner ends of said steps is equal so that said belt means need not have the length adjusted.
Dependencies are inferred from the claim text.