There are many accidents such that a passenger falls down on an escalator. Particularly, collision of a body, especially, a head with a corner where the tread and the riser of a step intersect may cause a major injury. Therefore, there is need for a safe escalator to absorb collision energy generated when a passenger falls down and hits his or her head against the corner, thereby avoiding a serious injury. While the escalator prevents the passenger from suffering a serious injury when he or she falls down, it should not have a structure that encourages the passenger to fall down in a normal use state.
As a means for preventing the passenger from suffering a serious injury when his or her body collides with the corner, an escalator step in which a cleat strip made of a flexible polymeric material is mounted on a tread part corresponding to the corner is proposed (Patent Document 1: Jpn. Pat. Appln. Laid-Open Publication No. 04-77582). That is, Patent Document 1 discloses that by mounting a cleat strip made of a flexible polymeric material on a tread part corresponding to the corner, the degree of an injury can be reduced even if a passenger falls down on a step and hits his or her body against the corner of the step.
However, Patent Document 1 discloses that a cleat strip made of a flexible polymeric material is mounted on a tread part corresponding to the corner of the step of the escalator but does not concretely describe the type and hardness of a material of the cleat strip to be used for preventing an injury of the passenger when he or she falls down. Thus, in the escalator step described in Patent Document 1, it is difficult to reliably prevent an injury of the passenger, particularly, a serious head injury when he or she falls down.
As described above, the escalator step is required to absorb collision energy generated when the passenger falls down and hits his or her head, which is the most important part of the human body, against the corner, so as to avoid a serious injury. At the same time, the escalator step should not have such a flexible structure that encourages the passenger to fall down in a normal use state. That is, the cleat needs to have enough hardness so as not to be buckled by a load applied thereto when the passenger stands on the cleat or walk on the cleat.