Seat belt retractor

• US 20060267331A1
• Filed: 05/10/2006
• Published: 11/30/2006
• Est. Priority Date: 05/19/2004
• Status: Active Grant

• Current Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Tanaka, Koji
• Granted Patent: US 7,717,215 B2
• Time in Patent Office: Days
• US Class Current: 280/806
• CPC Class Codes: B60R 2022/4473 using an electric retraction device combined with a spring B60R2022/444, B60R2022/4466
• CPC Class Codes: B60R 2022/4666 characterised by electric actuators
• CPC Class Codes: B60R 2022/468 characterised by clutching means between actuator and belt reel
• CPC Class Codes: B60R 2022/4685 with means to adjust or regulate the tensioning force in relation to external parameters
• CPC Class Codes: B60R 22/44 with means for reducing belt tension during use under normal conditions not included in the retractor B60R22/19; B60R22/3405 takes precedence
• CPC Class Codes: B60R 22/46 Reels with means to tension the belt in an emergency by forced winding upelectrical circuits for triggering safety arrangements B60R21/01 ; tensioners using reels only guiding the belt during normal use, e.g. splitted reels B60R22/195

Abstract

A seat belt apparatus to be installed in a vehicle is structured such that a motor for rotating a spool of a seat belt retractor is controlled to drive in the belt winding direction to apply a first tension on a seat belt before a vehicle collision and the motor is controlled to drive in the belt winding direction to apply a second tension on the seat belt during the vehicle collision.

Claims

1. A seat belt retractor to be installed in a vehicle comprising:

an electric motor;

a spool driven by the electric motor, wherein the spool is capable of winding and unwinding a seat belt for restraining a vehicle occupant;

a motor speed reduction mechanism to reduce the rotation speed of the motor via a plurality of gears positioned between a driving shaft of the electric motor and the spool; and

a control mechanism to control the electric motor;

wherein when the seat belt is worn by the vehicle occupant the control mechanism is configured to control the motor in a first setting mode before a vehicle collision and in a second setting mode during the vehicle collision;

wherein the control mechanism is configured so that in the first setting mode the electric motor drives the spool in the belt winding direction to apply a first tension on the seat belt and in the second setting mode the electric motor drives the spool in the belt winding direction to apply a second tension on the seat belt.

2. A seat belt retractor as claimed in claim 1, wherein the control mechanism controls the electric motor to perform the first setting mode when a vehicle collision is predicted before the vehicle collision or when a vehicle collision is unavoidable before the vehicle collision and the control mechanism controls the electric motor to perform the second setting mode when the vehicle collision occurs, and wherein the second tension is larger than the first tension.

3. A seat belt apparatus to be installed in a vehicle comprising:

a seat belt to be worn by a vehicle occupant for restraining the vehicle occupant;

an electric motor;

a spool capable of winding and unwinding a seat belt according to the driving of the electric motor;

a motor speed reduction mechanism for reducing the rotation speed of the motor via a plurality of gears positioned between a driving shaft of the electric motor and the spool;

a control mechanism to control the driving of the electric motor;

a buckle fixed to a vehicle body;

a tongue attached to the seat belt and latched to the buckle when the seat belt is worn by the vehicle occupant; and

a detection sensor to detect the latching of the tongue to the buckle,

wherein when it is determined that the seat belt is worn by the vehicle occupant according to the information detected by the detection sensor, the control mechanism performs a first setting mode by controlling the electric motor to drive in the belt winding direction to apply a first tension on the seat belt before a vehicle collision and performs a second setting mode by controlling the electric motor to drive in the belt winding direction to apply a second tension on the seat belt during the vehicle collision.

4. A seat belt apparatus as claimed in claim 3, wherein the control mechanism controls the electric motor to perform the first setting mode when a vehicle collision is predicted before the vehicle collision or when a vehicle collision is unavoidable before the vehicle collision and the control mechanism controls the electric motor to perform the second setting mode when the vehicle collision occurs, wherein the second tension is larger than the first tension.

5. A vehicle comprising:

a seat belt apparatus, the apparatus includes;

a seat belt to be worn by a vehicle occupant for restraining the vehicle occupant;

an electric motor;

a spool capable of winding and unwinding a seat belt according to the driving of the electric motor;

a motor speed reduction mechanism for reducing the rotation speed of the motor via a plurality of gears positioned between a driving shaft of the electric motor and the spool;

a control mechanism to control the driving of the electric motor;

a buckle fixed to a vehicle body;

a tongue attached to the seat belt and latched to the buckle when the seat belt is worn by the vehicle occupant; and

a detection sensor to detect the latching of the tongue to the buckle,

wherein when it is determined that the seat belt is worn by the vehicle occupant according to the information detected by the detection sensor, the control mechanism performs a first setting mode by controlling the electric motor to drive in the belt winding direction to apply a first tension on the seat belt before a vehicle collision and performs a second setting mode by controlling the electric motor to drive in the belt winding direction to apply a second tension on the seat belt during the vehicle collision, and

wherein the seat belt apparatus is accommodated in an accommodating space in the vehicle.

6. A vehicle as claimed in claim 5, wherein the control mechanism controls the electric motor to perform the first setting mode when a vehicle collision is predicted before the vehicle collision or when a vehicle collision is unavoidable before the vehicle collision and the control mechanism controls the electric motor to perform the second setting mode when the vehicle collision occurs, wherein the second tension is larger than the first tension.