An intelligent retractor having a mode switching lever includes: a spool around which webbing is wound; a flywheel which is provided at one side of the spool and rotates along with the rotation of the spool; a locking unit which fixes the flywheel when a predetermined condition for preventing an extension of the webbing is satisfied; and a mode switching lever which rotates in a state in which the webbing is extended by a predetermined length or greater, and operates the locking unit so that the locking unit fixes the flywheel.

A locking mechanism comprising a coupling member comprising an arm portion which is rotatably supported by a housing and adapted to rotate in a predetermined direction in response to the actuation of the pretensioner mechanism, a pressing portion adapted to press the pawl towards an engagement direction with the ratchet gear, and a coupling portion adapted to couple the arm portion and the pressing portion; and a rotating device adapted to hold the arm portion restrict a reverse rotation thereof; in the actuation of the pretensioner mechanism, when the pawl, pressed by the pressing portion and in contact with the ratchet gear rotating in the take-up direction, passes over each of teeth of the ratchet gear, the coupling member is elastically twisted and deformed between the arm portion and the pressing portion to hold the pawl in a state of being urged toward the engagement direction with the ratchet gear.

A locking mechanism comprising a coupling member comprising an arm portion which is rotatably supported by a housing and adapted to rotate in a predetermined direction in response to the actuation of the pretensioner mechanism, a pressing portion adapted to press the pawl towards an engagement direction with the ratchet gear, and a coupling portion adapted to couple the arm portion and the pressing portion; and a rotating device adapted to hold the arm portion restrict a reverse rotation thereof; in the actuation of the pretensioner mechanism, when the pawl, pressed by the pressing portion and in contact with the ratchet gear rotating in the take-up direction, passes over each of teeth of the ratchet gear, the coupling member is elastically twisted and deformed between the arm portion and the pressing portion to hold the pawl in a state of being urged toward the engagement direction with the ratchet gear.

A safety belt retractor, comprising a frame (8) and a belt retracting cylinder (1), the retracting cylinder (1) being rotatably supported in the frame (8) and being composed to be used for winding a woven belt (2). The frame (8) comprises: a back plate (8h), which has a first side and a second side which are opposite to each other, and a first opening (20); a plurality of first supporting legs (8a,8b), extending from the first side of the back plate (8h); a first support plate (11), which is provided with a second opening (21) and is connected to free end regions of the first supporting legs (8a, 8b); a plurality of second supporting legs (8c, 8d, 8e, 8f), extending from the second side of the back plate (8h); and a second supporting plate (9), connected to the free end regions of the second supporting legs (8c, 8d, 8e, 8f). The first opening (20) and the second opening (21) receive the belt retracting cylinder (1). The safety belt retractor is simple in structure and easy to assembly. Also provided is a safety belt device comprising the safety belt retractor.

A safety belt retractor, comprising a frame (8) and a belt retracting cylinder (1), the retracting cylinder (1) being rotatably supported in the frame (8) and being composed to be used for winding a woven belt (2). The frame (8) comprises: a back plate (8h), which has a first side and a second side which are opposite to each other, and a first opening (20); a plurality of first supporting legs (8a,8b), extending from the first side of the back plate (8h); a first support plate (11), which is provided with a second opening (21) and is connected to free end regions of the first supporting legs (8a, 8b); a plurality of second supporting legs (8c, 8d, 8e, 8f), extending from the second side of the back plate (8h); and a second supporting plate (9), connected to the free end regions of the second supporting legs (8c, 8d, 8e, 8f). The first opening (20) and the second opening (21) receive the belt retracting cylinder (1). The safety belt retractor is simple in structure and easy to assembly. Also provided is a safety belt device comprising the safety belt retractor.

An engagement-side flange portion, one of a pair of flange portions on the respective axial ends of a webbing-take-up portion of a take-up drum, is positioned to face engagement teeth and includes a projecting portion formed to project radially outward from its peripheral edge that faces a pawl when the pawl moves to reach engagement position with the engagement teeth. Outer peripheral diameter of engagement-side flange portion is smaller than inner peripheral diameter defined with tip ends of engagement teeth. Maximum outer peripheral dimension formed by the projecting portion and engagement-side flange portion is larger than inner peripheral diameter defined with tip ends of engagement teeth. In a state where the take-up drum is attached to a housing, the projecting portion projects radially outward over inner peripheral diameter defined with tip ends of engagement teeth that is located at axially outward side of the projecting portion.

An engagement-side flange portion, one of a pair of flange portions on the respective axial ends of a webbing-take-up portion of a take-up drum, is positioned to face engagement teeth and includes a projecting portion formed to project radially outward from its peripheral edge that faces a pawl when the pawl moves to reach engagement position with the engagement teeth. Outer peripheral diameter of engagement-side flange portion is smaller than inner peripheral diameter defined with tip ends of engagement teeth. Maximum outer peripheral dimension formed by the projecting portion and engagement-side flange portion is larger than inner peripheral diameter defined with tip ends of engagement teeth. In a state where the take-up drum is attached to a housing, the projecting portion projects radially outward over inner peripheral diameter defined with tip ends of engagement teeth that is located at axially outward side of the projecting portion.

A seat belt retractor includes a vehicle acceleration sensor. The vehicle acceleration sensor includes a sensor holder including a placement surface and an attachment member to which the sensor holder is coupled. The attachment member is attached to the housing in a state in which the sensor holder is in either a first posture or a second posture. The sensor holder is configured to be coupled to the attachment member at any one of a plurality of angular positions. The plurality of angular positions are positions of the sensor holder in a case where the sensor holder rotates around a rotation axis. A plurality of sensor attachment angles corresponding to the plurality of angular positions are different between the first posture and the second posture. The plurality of sensor attachment angles are angles, with respect to the housing, of the center line of the placement surface.

A seatbelt retractor includes: a housing; a winding drum configured to wind a webbing and rotatable in a winding direction and a pull-out direction of the webbing; a lock member coupled to the winding drum to be not rotatable relative to the winding drum when a force for pulling out the webbing is less than a predetermined value and to be rotatable relative to the winding drum when the force exceeds the predetermined value; an impact energy absorber provided between the winding drum and the lock member and configured to absorb impact energy by relative rotation between the winding drum and the lock member; and a bush made of resin. The lock member includes a tubular shaft support portion, and the winding drum includes a protrusion disposed inside the shaft support portion. The bush made of resin is provided between the shaft support portion and the protrusion.

A seatbelt retractor includes: a housing; a winding drum configured to wind a webbing and rotatable in a winding direction and a pull-out direction of the webbing; a lock member coupled to the winding drum to be not rotatable relative to the winding drum when a force for pulling out the webbing is less than a predetermined value and to be rotatable relative to the winding drum when the force exceeds the predetermined value; an impact energy absorber provided between the winding drum and the lock member and configured to absorb impact energy by relative rotation between the winding drum and the lock member; and a bush made of resin. The lock member includes a tubular shaft support portion, and the winding drum includes a protrusion disposed inside the shaft support portion. The bush made of resin is provided between the shaft support portion and the protrusion.