Abstract: Provided is a seat belt retractor capable of having its assembly readily performed to increase assembly efficiency, simplifying shapes of components to readily manufacture the retractor and reduce manufacturing cost, and preventing a webbing from being hooked when the webbing is rewound. The seat belt retractor includes a housing constituting a main body of the seat belt retractor, a guide drum rotatably installed in the housing, a connector inserted into one side of the guide drum, a base member surrounding the connector, a gear member inserted into the base member, a cylinder for operating the gear member, a torsion bar inserted into the guide drum, a locking member fixedly inserted between the torsion bar and the guide drum, a locking clutch installed at one surface of the locking member, a mechanism cover installed at one surface of the locking clutch, and a friction spring installed in the mechanism cover to stop operation of a lock arm fixed to the locking clutch.

Abstract: Provided is a locking member mounting structure of a seat belt retractor including: a locking base coupled to one side of a guide drum; a locking clutch rotatably coupled to one side surface of the locking base; a lock arm coupled to one side surface of the locking clutch so as to rotate at a predetermined angle; and a mechanism cover covering the locking clutch and the lock arm, wherein a leaf spring is fixed to extend to one side from a boss formed in the center of the locking clutch, and a fixing piece projects from one surface of the lock arm so as to be fixed to the leaf spring. The leaf spring which returns the lock arm installed in the locking clutch is easily assembled, and assembly time of the leaf spring is reduced, thereby increasing productivity. Further, since the leaf spring has a curved portion or is formed in a stair shape, elasticity of the leaf spring is maintained, and deformation of the leaf spring is prevented.

Abstract: Provided is a torsion bar support structure of a seat belt retractor capable of smoothly rotating a rotary torsion bar and preventing deformation of the torsion bar due to moment applied to the torsion bar by coupling support members to both ends of the torsion bar. The torsion bar support structure of a seat belt retractor includes a housing constituting a main body of the seat belt retractor, a guide drum rotatably coupled to the housing, a torsion bar inserted into the guide drum, a base member fixed to one side of the housing, a locking member fixed to the other side of the housing, and a cylinder accommodating a piston therein to rotate a gear member fixed to the base member, the structure including: a bearing member coupled to the gear member, and a cap surrounding a cover fixing shaft projecting from the locking member, wherein the bearing member and the cap rotatably support the torsion bar when rotation moment is applied in a circumferential direction and an axial direction of the torsion bar.

Abstract: Provided is a pretensioner for a seat belt retractor. The pretensioner for a seat belt retractor of a vehicle includes a torsion bar on which a webbing is wound; a gear member connected to the torsion bar; a base member with which the gear member is meshed and through which the torsion bar passes; a cylinder having a movement guide hole formed therein to supply a gas upon rapid deceleration of the vehicle; a piston having a rack formed at a side surface thereof in a longitudinal direction to be meshed with the gear member and moved along the movement guide hole upon supply of a gas, and; a cylindrical sealing operation part integrally formed with a bottom of the piston and projecting therefrom; and a sealing part coupled to an outer periphery of the sealing operation part to seal between the piston and an inner wall of the cylinder, wherein the base member has a hooking means for hooking the piston to a rack.

Abstract: Provided is a pretensioner for a seat belt retractor. The pretensioner for a seat belt retractor of a vehicle includes a torsion bar on which a webbing is wound; a gear member connected to the torsion bar; a base member with which the gear member is meshed and through which the torsion bar passes; a cylinder having a movement guide hole formed therein to supply a gas upon rapid deceleration of the vehicle; a piston having a rack formed at a side surface thereof in a longitudinal direction to be meshed with the gear member and moved along the movement guide hole upon supply of a gas, and; a cylindrical sealing operation part integrally formed with a bottom of the piston and projecting therefrom; and a sealing part coupled to an outer periphery of the sealing operation part to seal between the piston and an inner wall of the cylinder, wherein the base member has a hooking means for hooking the piston to a rack.

Abstract: Provided is a locking member mounting structure of a seat belt retractor including: a locking base coupled to one side of a guide drum; a locking clutch rotatably coupled to one side surface of the locking base; a lock arm coupled to one side surface of the locking clutch so as to rotate at a predetermined angle; and a mechanism cover covering the locking clutch and the lock arm, wherein a leaf spring is fixed to extend to one side from a boss formed in the center of the locking clutch, and a fixing piece projects from one surface of the lock arm so as to be fixed to the leaf spring. The leaf spring which returns the lock arm installed in the locking clutch is easily assembled, and assembly time of the leaf spring is reduced, thereby increasing productivity. Further, since the leaf spring has a curved portion or is formed in a stair shape, elasticity of the leaf spring is maintained, and deformation of the leaf spring is prevented.

Abstract: Provided is a seat belt retractor capable of having its assembly readily performed to increase assembly efficiency, simplifying shapes of components to readily manufacture the retractor and reduce manufacturing cost, and preventing a webbing from being hooked when the webbing is rewound. The seat belt retractor includes a housing constituting a main body of the seat belt retractor, a guide drum rotatably installed in the housing, a connector inserted into one side of the guide drum, a base member surrounding the connector, a gear member inserted into the base member, a cylinder for operating the gear member, a torsion bar inserted into the guide drum, a locking member fixedly inserted between the torsion bar and the guide drum, a locking clutch installed at one surface of the locking member, a mechanism cover installed at one surface of the locking clutch, and a friction spring installed in the mechanism cover to stop operation of a lock arm fixed to the locking clutch.

Abstract: Provided is a cover structure of a seat belt retractor including a mechanism cover having a latch formed at a cylindrical inner periphery thereof and a vehicle sensor installed at a lower part thereof, in order to reduce assembly time of the vehicle sensor, characterized in that the mechanism cover has an accommodating part having an opened lower surface for disposing the vehicle sensor therein, the accommodating part has a fixing hole formed at one side surface thereof, and the vehicle sensor has a fixing projection projecting from a position corresponding to the fixing hole. Therefore, it is possible to very conveniently and readily assemble the vehicle sensor to the mechanism cover using the cover structure. In addition, since the accommodating part is supported by an extension part, it is possible to prevent deformation of the accommodating part, despite prolonged use. Further, it is possible to reduce assembly time of the vehicle sensor to thereby increase productivity.

Abstract: Provided is a torsion bar support structure of a seat belt retractor capable of smoothly rotating a rotary torsion bar and preventing deformation of the torsion bar due to moment applied to the torsion bar by coupling support members to both ends of the torsion bar. The torsion bar support structure of a seat belt retractor includes a housing constituting a main body of the seat belt retractor, a guide drum rotatably coupled to the housing, a torsion bar inserted into the guide drum, a base member fixed to one side of the housing, a locking member fixed to the other side of the housing, and a cylinder accommodating a piston therein to rotate a gear member fixed to the base member, the structure including: a bearing member coupled to the gear member, and a cap surrounding a cover fixing shaft projecting from the locking member, wherein the bearing member and the cap rotatably support the torsion bar when rotation moment is applied in a circumferential direction and an axial direction of the torsion bar.