Breakaway latch plate

• US 6,708,380 B2
• Filed: 03/20/2002
• Issued: 03/23/2004
• Est. Priority Date: 03/20/2002
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Soderstrom, Pontus, Schneider, David W.
• Primary Examiner(s): Knight, Anthony
• Assistant Examiner(s): JACKSON, ANDRE L
• Application Number:
  US10/104,261
• Publication Number:
  US 20030177621A1
• Time in Patent Office: 734 Days
• Field of Search: 246/29, 246/33, 246/35, 246/36, 246/56, 246/64, 241/36.R, 241/36.K, 280/801.1, 280/801.2, 280/802, 280/807, 280/808
• US Class Current: 24/633
• CPC Class Codes: A44B 11/12 turnable clamp
• CPC Class Codes: B60R 2022/026 at least two ends of the belt being retractable after use
• CPC Class Codes: B60R 2022/1812 Connections between seat belt and buckle tongue
• CPC Class Codes: B60R 21/18 the inflatable member formed as a belt or harness or combined with a belt or harness arrangement
• CPC Class Codes: B60R 22/023 Three-point seat belt systems comprising two side lower and one side upper anchoring devices B60R22/022, B60R22/03 take precedence
• CPC Class Codes: B60R 22/30 Coupling devices other than buckles, including length-adjusting fittings or anti-slip devices adaptations of manual three-point seat belt systems for use by small passengers using other means than belt anti-slip devices B60R22/024; buckles A44B11/00; releasable fastenings in general F16B
• CPC Class Codes: Y10T 24/45602 Receiving member includes either movable connection between interlocking components or variable configuration cavity
• CPC Class Codes: Y10T 24/45623 and operator therefor
• CPC Class Codes: Y10T 24/45639 including pivotally connected element on receiving member

Abstract

A breakaway latch plate for use with the seat belt system is disclosed. The breakaway latch plate includes a latch plate body that may be selectively secured to a buckle. An orifice may be disposed within the latch plate body. Seat belt webbing passes through the orifice. A locking mechanism is coupled to the latch plate body. In a locked state, the locking mechanism prevents movement of the seat belt webbing relative to the latch plate body. When a predetermined load is applied to the seat belt webbing, the locking mechanism changes to an unlocked state, in which the seat belt webbing may move relative to the latch plate body.

Claims

1. A latch plate for use with seat belt webbing, comprising:

a latch plate body having an interior surface defining an orifice through which seat belt webbing passes;

a buckle for interfacing with the latch plate body; and

a locking mechanism coupled to the latch plate body, the locking mechanism having a locked and an unlocked state, wherein in the locked state, the locking mechanism prevents movement of the seat belt webbing relative to the latch plate body and in the unlocked state, the locking mechanism permits movement of the seat belt webbing relative to the latch plate body, and wherein, when the latch plate body is secured to the buckle, the locking mechanism changes from the locked state to the unlocked state in response to at least a predetermined load being applied to the seat belt webbing.

2. The seat belt system as defined in claim 1, wherein the locking mechanism comprises:

a cam having a guide track, a pin opening, and a movable gripping mechanism, wherein the movable gripping mechanism contacts and grips the seat belt webbing when the locking mechanism is in a locked state;

a guide pin attached to the latch plate body and disposed within the guide track;

a breakaway pin attached to the latch plate body and disposed within the pin opening, wherein the breakaway pin breaks upon the application of at least the predetermined load to the seat belt webbing to enable the cam to rotate about the guide pin and separate the gripping mechanism from the seat belt webbing; and

a fixed gripping mechanism for contacting and gripping the seat belt webbing when the locking mechanism is in the locked state.

3. The seat belt system as defined in claim 2, wherein the movable gripping mechanism comprises teeth inclined to limit movement of the seat belt webbing through the orifice toward the torso retractor and the fixed gripping mechanism comprises teeth inclined to limit movement of the seat belt webbing through the orifice toward the lap retractor.

4. The seat belt system as defined in claim 1, further comprising an aperture disposed within the seat belt webbing, and wherein the locking mechanism comprises a locking pin disposed within the aperture when the locking mechanism is in the locked state.

5. The seat belt system as defined in claim 4, wherein the interior surface defines a retention notch within the orifice, and wherein the locking mechanism further comprises a hinged cam rotatably connected to the latch plate body, wherein the locking pin is deformable and is attached to the hinged cam, and wherein, in the locked state, the locking pin is disposed within the aperture and retained within the retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin deforms and is displaced from within the aperture and retention notch as the hinged cam rotates away from the seat belt webbing.

6. The seat belt system as defined in claim 4, wherein the locking pin is frangible and comprises a first and a second end, and wherein the interior surface defines at least one retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends of the locking pin are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin breaks to permit movement of the seat belt webbing relative to the latch plate body.

7. The seat belt system as defined in claim 4, wherein the locking pin comprises a first and a second end, and wherein the interior surface defines at least one frangible retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends of the locking pin are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the at least one frangible notch breaks to permit movement of the seat belt webbing relative to the latch plate body.

8. A seat belt apparatus, comprising:

seat belt webbing;

a latch plate body having an interior surface defining an orifice through which the seat belt webbing passes;

a buckle for interfacing with the latch plate body; and

a locking mechanism coupled to the latch plate body, the locking mechanism having a locked and an unlocked state, wherein in the locked state, the locking mechanism prevents movement of the seat belt webbing relative to the latch plate body and in the unlocked state, the locking mechanism permits movement of the seat belt webbing relative to the latch plate body, and wherein, when the latch plate body is secured to the buckle, the locking mechanism changes from the locked state to the unlocked state in response to at least a predetermined load being applied to the seat belt webbing.

9. The seat belt apparatus as defined in claim 8, wherein the locking mechanism comprises:

a cam having a guide track, a pin opening, and a movable gripping mechanism, wherein the movable gripping mechanism contacts and grips the seat belt webbing when the locking mechanism is in a locked state;

a guide pin attached to the latch plate body and disposed within the guide track; and

a breakaway pin attached to the latch plate body and disposed within the pin opening, wherein the breakaway pin breaks upon the application of at least the predetermined load to the seat belt webbing to enable the cam to rotate about the guide pin and separate the gripping mechanism from the seat belt webbing.

10. The seat belt apparatus as defined in claim 9, further comprising frictional undulations disposed on the cam, wherein the frictional undulations contact the seat belt webbing when the locking mechanism is in an unlocked state.

11. The seat belt apparatus as defined in claim 9, wherein the locking mechanism further comprises a fixed gripping mechanism for contacting and gripping the seat belt webbing when the locking mechanism is in a locked state.

12. The seat belt apparatus as defined in claim 8, further comprising an aperture disposed within the seat belt webbing, and wherein the locking mechanism comprises a locking pin disposed within the aperture when the locking mechanism is in the locked state.

13. The seat belt apparatus as defined in claim 12, wherein the interior surface defines a retention notch within the orifice, and wherein the locking mechanism further comprises a hinged cam rotatably connected to the latch plate body, wherein the locking pin is deformable and is attached to the hinged cam, and wherein, in the locked state, the locking pin is disposed within the aperture and retained within the retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin deforms and is displaced from within the aperture and retention notch as the hinged cam rotates away from the seat belt webbing.

14. The seatbelt apparatus as defined in claim 12, wherein the locking pin is frangible and comprises a first and a second end, and wherein the interior surface defines at least one retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin breaks to permit movement of the seat belt webbing relative to the latch plate body.

15. The seatbelt apparatus as defined in claim 12, wherein the locking pin comprises a first and a second end, and wherein the interior surface defines at least one frangible retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the at least one frangible notch breaks to permit movement of the seat belt webbing relative to the latch plate body.

16. A seat belt system comprising:

seat belt webbing having a first and a second end;

a torso retractor coupled to the first end of the seat belt webbing;

a lap retractor coupled to the second end of the seat belt webbing;

a latch plate body having an interior surface defining an orifice through which the seat belt webbing passes;

a buckle for interfacing with the latch plate body; and

a locking mechanism coupled to the latch plate body, the locking mechanism having a locked and an unlocked state, wherein in the locked state, the locking mechanism prevents movement of the seat belt webbing relative to the latch plate body and in the unlocked state, the locking mechanism permits movement of the seat belt webbing relative to the latch plate body, and wherein, when the latch plate body is secured to the buckle, the locking mechanism changes from the locked state to the unlocked state in response to at least a predetermined load being applied to the seat belt webbing.

17. The latch plate as defined in claim 16, wherein the locking mechanism comprises:

a cam having a guide track, a pin opening, and a movable gripping mechanism, wherein the movable gripping mechanism contacts and grips the seat belt webbing when the locking mechanism is in a locked state;

a guide pin attached to the latch plate body and disposed within the guide track; and

a breakaway pin attached to the latch plate body and disposed within the pin opening, wherein the breakaway pin breaks upon the application of at least the predetermined load to the seat belt webbing to enable the cam to rotate about the guide pin and separate the gripping mechanism from the seat belt webbing.

18. The latch plate as defined in claim 17, further comprising a fixed gripping mechanism attached to the latch plate body that contacts and grips the seat belt webbing when the locking mechanism is in a locked state.

19. The latch plate as defined in claim 16, further comprising an aperture disposed within the seat belt webbing, and wherein the locking mechanism comprises a locking pin disposed within the aperture when the locking mechanism is in the locked state.

20. The latch plate as defined in claim 19, wherein the interior surface defines a retention notch within the orifice, and wherein the locking mechanism further comprises a hinged cam rotatably connected to the latch plate body, wherein the locking pin is deformable and is attached to the hinged cam, and wherein, in the locked state, the locking pin is disposed within the aperture and retained within the retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin deforms and is displaced from within the aperture and retention notch as the hinged cam rotates away from the seat belt webbing.

21. The latch plate as defined in claim 19, wherein the locking pin is frangible and comprises a first and a second end, and wherein the interior surface defines at least one retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the locking pin breaks to permit movement of the seat belt webbing relative to the latch plate body.

22. The latch plate as defined in claim 19, wherein the locking pin comprises a first and a second end, and wherein the interior surface defines at least one frangible retention notch within the orifice for receiving the first and second ends of the locking pin, and wherein when the locking mechanism is in a locked state, the locking pin is disposed through the aperture and the first and the second ends are retained within the at least one retention notch, and wherein when at least the predetermined load is applied to the seat belt webbing the at least one frangible notch breaks to permit movement of the seat belt webbing relative to the latch plate body.

23. The latch plate as defined in claim 16, wherein the seat belt webbing comprises inflatable seat belt webbing.