An occupant protection device includes a drive unit which adjusts a degree of tension of a seat belt and a control unit which controls the drive unit to tension the seat belt to remove looseness of the seat belt when a vehicle has been switched from an automated driving to a manual driving.

An occupant protection device includes a drive unit which adjusts a degree of tension of a seat belt and a control unit which controls the drive unit to tension the seat belt to remove looseness of the seat belt when a vehicle has been switched from an automated driving to a manual driving.

A motorized seat belt system includes: a spindle around which webbing is wound; an output gear connected to the spindle through a power transmission shaft; a torsion portion provided on the power transmission shaft or the output gear; a motor which transmits rotational power to the spindle; first and second reduction gears which are connected to an output shaft of the motor and transmit rotational power of the motor to the output gear; a first rotation amount detecting sensor that measures a rotation angle and a rotation direction of the power transmission shaft; a second rotation amount detecting sensor that measures a rotation angle and a rotation direction with respect to a rim portion of the first reduction gear; and a controller which controls output of the motor based on detection signals from the first rotation amount detecting sensor and the second rotation amount detecting sensor.

A motorized seat belt system includes: a spindle around which webbing is wound; an output gear connected to the spindle through a power transmission shaft; a torsion portion provided on the power transmission shaft or the output gear; a motor which transmits rotational power to the spindle; first and second reduction gears which are connected to an output shaft of the motor and transmit rotational power of the motor to the output gear; a first rotation amount detecting sensor that measures a rotation angle and a rotation direction of the power transmission shaft; a second rotation amount detecting sensor that measures a rotation angle and a rotation direction with respect to a rim portion of the first reduction gear; and a controller which controls output of the motor based on detection signals from the first rotation amount detecting sensor and the second rotation amount detecting sensor.

A belt retractor includes a retractor frame (10) having first and second end faces (10a, 10b) between which a belt reel (12) is pivoted. The belt retractor further includes a belt tensioner and a spring cassette (30) having a helical spring (26) coupled to the belt reel (12). The spring cassette (30) is arranged between the first end face (10a) of the retractor frame (10) and at least one component of the belt tensioner. A method of fitting such belt retractor includes mounting the spring cassette (30) on a component of the belt tensioner, especially on an inside of a tensioner casing (22) and mounting the belt tensioner including the spring cassette (30) on the retractor frame (10), especially on an end wall (10a) of the retractor frame (10). An alternative fitting method includes mounting the spring cassette (30) on an end wall (10a) of the retractor frame (10) and attaching the belt tensioner to the spring cassette (30) mounted on the end wall (10a) of the retractor frame (10).

A belt retractor includes a retractor frame (10) having first and second end faces (10a, 10b) between which a belt reel (12) is pivoted. The belt retractor further includes a belt tensioner and a spring cassette (30) having a helical spring (26) coupled to the belt reel (12). The spring cassette (30) is arranged between the first end face (10a) of the retractor frame (10) and at least one component of the belt tensioner. A method of fitting such belt retractor includes mounting the spring cassette (30) on a component of the belt tensioner, especially on an inside of a tensioner casing (22) and mounting the belt tensioner including the spring cassette (30) on the retractor frame (10), especially on an end wall (10a) of the retractor frame (10). An alternative fitting method includes mounting the spring cassette (30) on an end wall (10a) of the retractor frame (10) and attaching the belt tensioner to the spring cassette (30) mounted on the end wall (10a) of the retractor frame (10).

In the webbing winding device, the rotation of the output shaft of the motor is transmitted to the spool via the first gear train. In this state, when the rotation speed of the spool decreases and the rotation of the slider base of the first clutch decreases, the coupling pawl of the second clutch is pressed by the slider provided on the slider base to mesh with the ratchet gear, and the rotation of the output shaft of the motor is transmitted to the spool via the second gear train.

In the webbing winding device, the rotation of the output shaft of the motor is transmitted to the spool via the first gear train. In this state, when the rotation speed of the spool decreases and the rotation of the slider base of the first clutch decreases, the coupling pawl of the second clutch is pressed by the slider provided on the slider base to mesh with the ratchet gear, and the rotation of the output shaft of the motor is transmitted to the spool via the second gear train.

A webbing take-up device includes a second clutch that transmits rotation of a motor to a spool. The second clutch includes a base including a first spring catch portion, a clutch gear, a clutch spring including a coil portion, having an end portion at one side caught to the first spring catch portion, and a lever that includes a second spring catch portion catching an end portion at another side of the clutch spring, and that enlarges diameter of the coil portion to abut the clutch gear by moving the end portion at the another side of the clutch spring toward one side in the circumferential direction of the base. A terminal end of the end portion at the one side of the clutch spring abuts the first spring catch portion when the lever is rotated toward the one side in the circumferential direction of the base.

A webbing take-up device includes a second clutch that transmits rotation of a motor to a spool. The second clutch includes a base including a first spring catch portion, a clutch gear, a clutch spring including a coil portion, having an end portion at one side caught to the first spring catch portion, and a lever that includes a second spring catch portion catching an end portion at another side of the clutch spring, and that enlarges diameter of the coil portion to abut the clutch gear by moving the end portion at the another side of the clutch spring toward one side in the circumferential direction of the base. A terminal end of the end portion at the one side of the clutch spring abuts the first spring catch portion when the lever is rotated toward the one side in the circumferential direction of the base.