WEBBING WINDER

PROBLEM TO BE SOLVED: To improve position accuracy between a piston and a pinion by suppressing an increase in the number of components.SOLUTION: A webbing winder 10 includes a cylinder 42 having a housing part 60 for housing a piston 90 and a guide part 44 extended from one end part of the housing part 60 in a long direction. A pinion 70 is rotatably supported by the guide part 44, and the piston 90 is guided by the guide part 44. Therefore, it is not necessary to arrange a member for housing the piston 90 and a member for rotatably supporting the pinion 70 separately. Thus, an increase in the number of components can be suppressed. In addition, as the piston 90 and the pinion 70 are arranged on the cylinder 42, respective positions of the piston 90 and the pinion 70 are determined by the cylinder 42. Therefore, as compared with a case that the member for housing the piston 90 and the member for rotatably supporting the pinion 70 are separately arranged, position accuracy between the piston 90 and the pinion 70 can be improved.