Automotive passenger restraint and protection apparatus and seatbelt protraction and retraction amount-detecting device

• US 6,485,057 B1
• Filed: 05/25/2000
• Issued: 11/26/2002
• Est. Priority Date: 12/16/1997
• Status: Expired due to Term

• Current Assignee: NSK Autoliv Co., Ltd. (Autoliv Incorporated)
• Original Assignee: NSK Autoliv Co., Ltd. (Autoliv Incorporated)
• Inventors: Ogawa, Kiyoshi, Matsuki, Masuo, Midorikawa, Yukinori, Kawai, Osamu
• Primary Examiner(s): Dickson, Paul N.
• Assistant Examiner(s): WINNER, TONY H
• Application Number:
  US09/578,464
• Time in Patent Office: 915 Days
• Field of Search: 280/806, 280/802, 280/801.1, 280/807, 280/805, 180/268, 701/36, 701/45
• US Class Current: 280/807
• CPC Class Codes: B60R 2021/01272 Belt tensioners
• CPC Class Codes: B60R 2021/01313 monitoring the vehicle steering system or the dynamic control system
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 2022/029 Belt storage; Devices or systems for controlling winding up of unused seat belt
• CPC Class Codes: B60R 2022/444 the additional retraction device being an electric actuator
• CPC Class Codes: B60R 2022/4473 using an electric retraction device combined with a spring B60R2022/444, B60R2022/4466
• CPC Class Codes: B60R 2022/4609 using a plurality of tensioners
• CPC Class Codes: B60R 2022/4657 comprising a plurality of charges
• CPC Class Codes: B60R 2022/4666 characterised by electric actuators
• CPC Class Codes: B60R 2022/4685 with means to adjust or regulate the tensioning force in relation to external parameters
• CPC Class Codes: B60R 21/01 Electrical circuits for triggering passive safety arrangements, e.g. airbags, safety belt tighteners, in case of vehicle accidents or impending vehicle accidents electrical circuits for transmission of signals between steering wheel and the vehicle itself B60R16/027; for electrically actuating belt retractor locking means B60R22/343
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: B60R 21/01546 using belt buckle sensors
• CPC Class Codes: B60R 21/01552 detecting position of specific human body parts, e.g. face, eyes or hands
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves
• CPC Class Codes: B60R 22/405 responsive to belt movement and vehicle movement
• 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
• CPC Class Codes: B60R 22/4633 Linear actuators, e.g. comprising a piston moving along reel axis and rotating along its own axis

Abstract

An automotive passenger restraint and protection apparatus for an automotive vehicle has a seatbelt and operates to restrain an occupant of the automotive vehicle by the seatbelt to protect the occupant. An electric retractor has a DC motor for retracting and protracting the seatbelt. An MPU controls the DC motor. Protraction of the seatbelt by the occupant is detected. When the protraction of said belt is detected, the MPU controls the DC motor so as to protract the seatbelt. A seatbelt protraction and retraction amount-detecting device calculates an amount of protraction or retraction of the seatbelt, based upon at least one of a number of times pulsating components of detected terminal voltage across the DC motor rises above a first predetermined value from a value below a first predetermined value, a number of times the pulsating components drops below a second predetermined value from a value above the second predetermined value, a frequency component obtained by frequency analysis of the pulsating components, and results of time integration of the detected terminal voltage, and a detected rotational direction of the motor.

Claims

1. An automotive passenger restraint and protection apparatus for an automotive vehicle, having a seatbelt, for restraining an occupant of the automotive vehicle by the seatbelt to protect the occupant, comprising:

an electric retractor having driving means, which comprises a DC motor, for retracting and protracting the seatbelt;

control means for controlling said driving means; and

detecting means for detecting protraction of the seatbelt by the occupant based upon terminal voltage across the DC motor;

wherein when the protraction of said seatbelt is detected by said detecting means, said control means controls said driving means so as to protract the seatbelt.

2. An automotive passenger restraint and protection apparatus as claimed in claim 1, further comprising a power supply, and supply means for supplying supply voltage from said power supply to said driving means, and wherein said control means controls a driving operation of said driving means by controlling a magnitude of said supply voltage or a degree of modulation of pulse width thereof.

3. An automotive passenger restraint and protection apparatus as claimed in claim 1, including seatbelt locking means for locking the seatbelt from being protracted when the seatbelt is protracted at a predetermined or high degree of acceleration, and wherein said control means controls said driving means to thereby control speed of protraction or retraction of the seatbelt at least one of conditions is satisfied that said driving means stops retracting driving of the seatbelt, said driving means starts protracting driving of the seatbelt from a stopped state of the seatbelt, and said driving means shifts from the retracting driving of the seatbelt to protracting driving of the seatbelt.

4. An automotive passenger restraint and protection apparatus as claimed in claim 1, including seatbelt locking means for locking the seatbelt from being protracted when the seatbelt is at a predetermined or high degree of acceleration, and wherein when the seatbelt is locked from being protracted by said seatbelt locking means, said control means controls said driving means to retract the seatbelt to a limit thereof and then protract the seatbelt for a predetermined time period.

5. An automotive passenger restraint and protection apparatus as claimed in claim 4, wherein when the seatbelt has been retracted to said limit thereof by said driving means, said control means controls said driving means to protract the seatbelt by a first predetermined amount and then again retract the seatbelt by a second predetermined amount smaller than said first predetermined amount.

6. An automotive passenger restraint and protection apparatus as claimed in claim 4, including acceleration detecting means for detecting acceleration of protraction of the seatbelt when the seatbelt is protracted, and abnormality diagnosis means for carrying out diagnosis as to abnormality of said seatbelt locking means by making a determination as to whether said seatbelt locking means has operated in response to the acceleration detected by said acceleration detecting means, and determining abnormality of said seatbelt locking means, based upon results of said determination.

7. An automotive passenger restraint and protection apparatus for an automotive vehicle, having a seatbelt, for restraining an occupant of the automotive vehicle by the seatbelt to protect the occupant, comprising:

an electric retractor having driving means for retracting and protracting the seatbelt;

control means for controlling said driving means;

seatbelt attaching detecting means for detecting whether the seatbelt is attached to the occupant or disconnected from the occupant; and

retraction limit detecting means for detecting whether the seatbelt has been retracted to a limit thereof;

wherein said control means controls said driving means in a manner such that when said seatbelt attaching detecting means detects that the seatbelt has become attached to the occupant from a state in which it is disconnected from the occupant, the seatbelt is retracted, and when said retraction limit detecting means subsequently detects that the seatbelt has been retracted to said limit thereof, the seatbelt is stopped from being retracted, and then the seatbelt is protracted for a predetermined time period.

8. An automotive passenger restraint and protection apparatus for an automotive vehicle, having a seatbelt, for restraining an occupant of the automotive vehicle by the seatbelt to protect the occupant, comprising:

a reel shaft having the seatbelt wound thereon;

a motor for rotating said reel shaft in a direction of protracting or retracting the seatbelt;

change amount detecting means-for detecting an amount of change in at least one of terminal voltage across said motor and current flowing to said motor;

seatbelt attaching detecting means for detecting attaching of the seatbelt-to the occupant or disconnection of the seatbelt from the occupant; and

control means for controlling said motor, based upon results of detections by said change amount detecting means and said seatbelt attaching detecting means.

9. A seatbelt protraction and retraction amount-detecting device for an automotive passenger restraint and protection apparatus having a seatbelt, and a motor for rotating protracting or retracting the seatbelt, comprising:

motor rotational direction detecting means for detecting rotational direction of the motor;

voltage detecting means for detecting terminal voltage across the motor; and

protraction/retraction amount calculating means for calculating an amount of protraction or an amount of retraction of the seatbelt, based upon at least one of a number of times pulsating components of the terminal voltage detected by said voltage detecting means rises above a first predetermined value from a value below said first predetermined value, a number of times said pulsating components drops below a second predetermined value from a value above said second predetermined value, a frequency component obtained by frequency analysis of the pulsating components, and results of time integration of the detected terminal voltage, and the rotational direction of said motor detected by said motor rotational direction detecting means.

10. An automotive passenger restraint and protection apparatus for an automotive vehicle, having a seatbelt, for restraining an occupant of the automotive vehicle by the seatbelt to protect the occupant, comprising:

an electric retractor having driving means for retracting and protracting the seatbelt;

control means for controlling said driving means;

seatbelt attaching detecting means for detecting attaching of the seatbelt to the occupant or disconnection of the seatbelt from the occupant;

protraction stoppage detecting means for detecting stoppage of protraction of the seatbelt; and

vehicle speed detecting means for detecting traveling speed of the automotive vehicle;

wherein said control means inhibits said driving means from retracting the seatbelt if the traveling speed of the automotive vehicle detected by said vehicle speed detecting means is lower than a predetermined value when the stoppage of protraction of the seatbelt is detected by the protraction stoppage detecting means after the attaching of the seatbelt to the occupant is detected by said seatbelt attaching means.