Seat belt system with dual payout retractor

• US 20040026981A1
• Filed: 08/06/2002
• Published: 02/12/2004
• Est. Priority Date: 08/06/2002
• Status: Active Grant

• Current Assignee: TRW Vehicle Safety Systems Incorporated (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Vehicle Safety Systems Incorporated (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Kotivosky, Alex P., Zwolinski, Joseph J., Herberg, Arnold J., Maloney, Barry J.
• Granted Patent: US 6,824,222 B2
• Time in Patent Office: Days
• US Class Current: 297/474
• CPC Class Codes: B60R 2022/1825 using rollers
• CPC Class Codes: B60R 2022/3424 Multi-spool or multi-belt retractors
• CPC Class Codes: B60R 2022/3427 Seat belt connection on reels
• CPC Class Codes: B60R 22/1855 the means being sensitive to belt tension
• CPC Class Codes: B60R 22/26 secured to the seat
• CPC Class Codes: B60R 22/3416 Unlocking devices for retractors B60R22/3405 takes precedence
• CPC Class Codes: B60R 22/42 having means for acting directly upon the belt, e.g. by clamping or friction not combined with the retractor B60R22/185

Abstract

A seat belt system (10) includes a lap belt (60) including a first portion (74) and a second portion (85). A retractor (76) includes a spool (96) rotatable about an axis (160). The first and second lap belt portions (74, 85) are secured to the spool (96). The spool (96) is biased to rotate in a first rotational direction to wind the first and second portions (74, 85) onto the spool. The first and second portions (74, 85) when tensioned urge the spool (96) to rotate in a second rotational direction opposite said first rotational direction to unwind the first and second portions from the spool. A locking mechanism (170) is actuatable to lock the spool (96) against rotation in the second rotational direction. First and second web grabbing devices (180, 182) are actuatable to clamp onto the first and second portions (74, 85) when the locking mechanism (170) is in the locked condition.

Claims

1. A seat belt system for helping to restrain an occupant of a vehicle seat, said seat belt system comprising:

a lap belt comprising first and second portions extensible adjacent opposite sides of the vehicle seat and across a seating portion of the vehicle seat;

a buckle assembly for releasably connecting said first and second portions of said lap belt while extended across the vehicle seat; and

a retractor comprising;

a spool rotatable about an axis, said first and second portions of said lap belt being secured to said spool, said spool being biased to rotate in a first rotational direction to wind said first and second portions onto said spool, said first and second portions when tensioned urging said spool to rotate in a second rotational direction opposite said first rotational direction to unwind said first and second portions from said spool;

a locking mechanism actuatable to a locked condition to lock said spool against rotation in said second rotational direction;

a first web grabbing device actuatable to clamp onto said first portion of said lap belt when said locking mechanism is in said locked condition; and

a second web grabbing device actuatable to clamp onto said second portion of lap belt when said locking mechanism is in said locked condition.

2. A seat belt system as recited in claim 1, wherein said first web grabbing device comprises a first actuator actuatable as a result of tension on said lap belt when said locking mechanism is in said locked condition, said first actuator when actuated urging opposing clamping surfaces of said first web grabbing device to clamp onto said first portion of said lap belt, and said second web grabbing device comprises a second actuator actuatable as a result of tension on said lap belt when said locking mechanism is in said locked condition, said second actuator when actuated urging opposing clamping surfaces of said second web grabbing device to clamp onto said second portion of said lap belt.

3. A seat belt system as recited in claim 2, further comprising a plate portion for supporting said spool and said first and second actuators, said spool being rotatable relative to said plate portion, said locking mechanism when in said locked condition blocking rotation of said spool relative to said plate portion in said second rotational direction, said plate portion pivoting as a result of tension on said lap belt while said locking mechanism is in said locked condition, said first and second actuators being actuated when said plate portion pivots.

4. The seat belt system recited in claim 2, wherein said opposing clamping surfaces of said first web grabbing device when engaging said first portion of said lap belt are urged together as a result of tension on said first portion of said lap belt, and said opposing clamping surfaces of said second web grabbing device when engaging said second portion of said lap belt are urged together as a result of tension on said second portion of said lap belt.

5. A seat belt system as recited in claim 1, wherein said first and second web grabbing devices each comprise a wedge clamp, each of said wedge clamps comprising:

a housing having a planar first sliding surface presented at an angle towards a planar second sliding surface;

first and second clamp members supported between the sliding surfaces, said first clamp member being slidable along said first sliding surface, said second clamp member being slidable along said second sliding surface, said first and second clamp members having respective clamping surfaces presented toward each other, said lap belt extending between said clamping surfaces, said first and second clamp members being actuatable to slide simultaneously along said first and second sliding surfaces, said clamping surfaces of said first and second clamp members moving toward each other and clamping onto said lap belt upon actuation of said clamp members.

6. A seat belt system as recited in claim 5, further comprising a first actuator arm for actuating said first and second clamp members of said first web grabbing device, and a second actuator arm for actuating said first and second clamp members of said second web grabbing device, said first and second actuator arms being actuatable as a result of tension on said lap belt when said locking mechanism is in said locked condition.

7. A seat belt system as recited in claim 6, further comprising a plate portion for supporting said spool and said first and second actuator arms, said spool being rotatable relative to said plate portion, said locking mechanism when in said locked condition blocking rotation of said spool relative to said plate portion in said second rotational direction, said plate portion pivoting as a result of tension on said lap belt while said locking mechanism is in said locked condition, said first and second actuator arms being actuated when said plate portion pivots.

8. A seat belt system as recited in claim 1 wherein said first and second web grabbing devices each comprise a rotary clamp, each of said rotary clamps comprising:

a base portion having a first clamping surface; and

a clamp member spaced from said base and having a second clamping surface presented toward said first clamping surface, said clamp member being pivotable in opposite first and second rotational directions, said lap belt extending between said clamping surfaces, said clamp member being actuatable to pivot in said first rotational direction to move said second clamping surface toward said first clamping surface, said first and second clamping surfaces clamping onto said lap belt upon actuation of said clamp member.

9. A seat belt system as recited in claim 8, further comprising a first actuator arm for engaging an actuator portion of said clamp member of said first web grabbing device to actuate said first web grabbing device, and a second actuator arm for engaging an actuator portion of said clamp member of said second web grabbing device to actuate said second web grabbing device, said first and second actuator arms being actuatable as a result of tension on said lap belt when said locking mechanism is in said locked condition.

10. A seat belt system as recited in claim 9, further comprising a plate portion for supporting said spool and said first and second actuator arms, said spool being rotatable relative to said plate portion, said locking mechanism when in said locked condition blocking rotation of said spool relative to said plate portion in said second rotational direction, said plate portion pivoting as a result of tension on said lap belt while said locking mechanism is in said locked condition, said first and second actuator arms being actuated when said plate portion pivots.

11. The seat belt system recited in claim 8, further comprising a first guide for guiding said first portion of said lap belt adjacent a first side of the vehicle seat, and a second guide for guiding said second portion of said lap belt adjacent a second side of the vehicle seat, said first guide being adapted to pivot as a result of tension on said first portion of said lap belt when said locking mechanism is in said locked condition, said first guide including a first actuator arm for engaging an actuator portion of said clamp member of said first web grabbing device to actuate said first web grabbing device when said first guide pivots, said second guide being adapted to pivot as a result of tension on said second portion of said lap belt when said locking mechanism is in said locked condition, said second guide including a second actuator arm for engaging an actuator portion of said clamp member of said second web grabbing device to actuate said second web grabbing device when said second guide pivots.

12. A seat belt system comprising:

a spool rotatable about an axis;

first and second portions of seatbelt webbing secured to said spool, said spool being biased to rotate in a first rotational direction to wind said first and second portions onto said spool, said first and second portions when tensioned urging said spool to rotate in a second rotational direction opposite said first rotational direction to unwind said first and second portions from said spool;

a locking mechanism actuatable to a locked condition to lock said spool against rotation in said second rotational direction;

a first web grabbing device actuatable under tension of said first portion of belt webbing to clamp onto said first portion of belt webbing when said locking mechanism is in said locked condition; and

a second web grabbing device actuatable under tension of said second portion of belt webbing to clamp onto said second portion of belt webbing when said locking mechanism is in said locked condition.

13. A seat belt system comprising:

a dual payout retractor including a spool rotatable about an axis;

a length of seat belt webbing having a central portion secured to said spool and first and second portions extending from said retractor, said retractor being operable to wind said first and second portions onto said spool to retract said first and second portions, said retractor being operable to unwind said first and second portions from said spool to payout said first and second portions;

a locking mechanism actuatable to a locked condition to lock said spool against unwinding said first and second portions;

a first web grabbing device actuatable under tension of said first portion to clamp onto said first portion when said locking mechanism is in said locked condition; and

a second web grabbing device actuatable under tension of said second portion to clamp onto said second portion when said locking mechanism is in said locked condition.