Escalator or moving walk, said escalator or moving walk comprising steps or pallets, and a balustrade with a handrail, having further a comb plate-comb plate carrier assembly being arranged on a head of the escalator or moving walk and being mounted on a truss of the escalator or moving walk; wherein said comb plate-comb plate carrier assembly comprising: a comb plate; and a pair of opposed comb plate carriers for carrying the comb plate; and wherein said comb plate-comb plate carrier assembly being provided with: a monitoring device for monitoring the horizontal displacement and upward displacement of the comb plate, characterized in that said monitoring device comprises: a safety switch fastened to the comb plate carrier, a safety switch actuating rod assembly for actuating the safety switch and a restoration device; wherein said safety switch actuating rod assembly comprising: a safety switch actuating rod, one end of which is attached to a shaft; the shaft is attached to the comb plate, and extends in the lateral direction of the comb plate and can move together with the comb plate; and said safety switch actuating rod can rotate about the axis of the shaft; a safety switch actuating pin which is fixedly attached to the other end of the safety switch actuating rod and is configured to actuate the safety switch; wherein said safety switch actuating rod is provided with a pin near said one end which extends substantially parallel to said shaft and is spaced apart by a distance from the shaft, the pin is located in a guide channel extending in a direction of horizontal displacement of the comb plate and is guided by the guide channel; and wherein said restoration device comprises: a pin, a helical spring and a wedge block, wherein said wedge block is fastened to the comb plate carrier on a side of the shaft opposed to the safety switch, and has an inclined surface or curved surface on the side facing the shaft, the inclined surface or curved surface forms an acute angle with a mounting surface of the comb plate carrier on which the wedge block is mounted, said wedge block is formed with a through hole extending through the inclined surface or curved surface and the surface opposed to the inclined surface or curved surface; said pin extends through the through hole, wherein the diameter of the through hole and that of the pin are so defined that the pin can follow the upward displacement of the comb plate; the end of the pin on the side of the shaft is fitted to the shaft, and the helical spring is fitted over the other end portion of the pin extending out of the through hole, one end of the helical spring abuts said wedge block and the other end of the helical spring abuts a stopper fastened to the other end of the pin; wherein said monitoring device further comprises a roller which is fitted over the shaft and comes into contact with the inclined surface or curved surface. a comb plate; and a pair of opposed comb plate carriers for carrying the comb plate; a monitoring device for monitoring the horizontal displacement and upward displacement of the comb plate, a safety switch actuating rod, one end of which is attached to a shaft; the shaft is attached to the comb plate, and extends in the lateral direction of the comb plate and can move together with the comb plate; and said safety switch actuating rod can rotate about the axis of the shaft; a safety switch actuating pin which is fixedly attached to the other end of the safety switch actuating rod and is configured to actuate the safety switch; wherein said wedge block is fastened to the comb plate carrier on a side of the shaft opposed to the safety switch, and has an inclined surface or curved surface on the side facing the shaft, the inclined surface or curved surface forms an acute angle with a mounting surface of the comb plate carrier on which the wedge block is mounted, said wedge block is formed with a through hole extending through the inclined surface or curved surface and the surface opposed to the inclined surface or curved surface; said pin extends through the through hole, wherein the diameter of the through hole and that of the pin are so defined that the pin can follow the upward displacement of the comb plate; the end of the pin on the side of the shaft is fitted to the shaft, and the helical spring is fitted over the other end portion of the pin extending out of the through hole, one end of the helical spring abuts said wedge block and the other end of the helical spring abuts a stopper fastened to the other end of the pin;