Seatbelt pretensioning retractor assembly

Patent metadata

Field	Value
Publication number	US-9744940-B1
Application number	US-201615097729-A
Country	US
Kind code	B1
Filing date	Apr 13, 2016
Priority date	Apr 13, 2016
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

A seatbelt pretensioning retractor assembly for use in a passenger vehicle is provided. The pretensioning assembly includes a tube in fluid communication with a gas generator and a driving element disposed therein that travels in a first direction in response to actuation of the gas generator. The driving element includes a plastically deformable polymer rod with a recessed portion. A stopper is coupled to an end portion of the plastically deformable polymer rod. A seal member is disposed between the gas generator and the stopper. The tube includes a projection extending within the tube adjacent to the exit to define a constriction portion. The constriction portion is sized to permit the recessed portion of the plastically deformable polymer rod to pass therethrough while preventing the stopper from passing therethrough.

First claim

The invention claimed is:

1. A seatbelt pretensioning retractor assembly for use in a passenger vehicle, the seatbelt pretensioning retractor assembly comprising:
a housing adapted for being mounted to a vehicle structure and having an interior cavity;
a tube having an arcuate and curved shape having a first end for fluid communication with a gas generator and a second end in fluid communication with the interior cavity of the housing;
a sprocket rotatably mounted to the housing and fixedly coupled to a spindle adapted for taking up seatbelt webbing during pretensioning, wherein the sprocket has a plurality of vanes;
a driving element comprising a plastically deformable polymer rod configured to extend in a longitudinal direction and having a recessed portion defining a recess that extends generally in the longitudinal direction, wherein the plastically deformable polymer rod is disposed within the tube and is translatable through the tube in a first direction toward the sprocket in response to an actuation by the gas generator;
a stopper coupled to an end portion of the plastically deformable polymer rod; and
a seal member disposed between the gas generator and the stopper, wherein the tube includes a projection extending within the tube adjacent to the exit to define a constriction portion that has an opening dimension smaller than an inside dimension of adjacent portions of the tube, and wherein the recess is aligned with the projection in the first direction and the constriction portion is sized to permit the recessed portion of the plastically deformable polymer rod to pass therethrough while preventing the stopper from passing therethrough.

2. The seatbelt pretensioning retractor assembly of claim 1 , wherein the recess is in a form of a groove defined by the recessed portion.

3. The seatbelt pretensioning retractor assembly of claim 1 , wherein the recessed portion has a recessed ruled surface that defines the recess.

4. The seatbelt pretensioning retractor assembly of claim 1 , wherein the plastically deformable polymer rod has a proximal end portion that is disposed towards the gas generator and a distal end portion that is opposite the proximal end portion, and wherein the stopper is coupled to the proximal end portion and the recessed portion extends distally from the proximal end portion to and includes the distal end portion.

5. The seatbelt pretensioning retractor assembly of claim 4 , wherein the proximal end portion comprises a non-recessed portion that has a diameter, cross-sectional dimension, and/or perimeter greater than the recessed portion.

6. The seatbelt pretensioning retractor assembly of claim 5 , wherein the stopper abuts the non-recessed portion and has an outer perimeter that substantially matches the perimeter the non-recessed portion.

7. The seatbelt pretensioning retractor assembly of claim 4 , wherein the plastically deformable polymer rod and the stopper are fixedly couple together by a positive feature extending generally in the longitudinal direction received by a negative feature.

8. The seatbelt pretensioning retractor assembly of claim 1 , wherein the plastically deformable polymer rod has a recessed section extending in the longitudinal direction on a side opposite the recessed portion.

9. The seatbelt pretensioning retractor assembly of claim 1 , wherein the projection is integrally formed with the tube.

10. The seatbelt pretensioning retractor assembly of claim 9 , wherein the projection is in a form of a protrusion in a sidewall of the tube.

11. The seatbelt pretensioning retractor assembly of claim 9 , wherein the projection is in a form of a crimp in a sidewall of the tube.

12. The seatbelt pretensioning retractor assembly of claim 9 , wherein the constriction portion and the adjacent portions of the tube form a monolithic structure.

13. The seatbelt pretensioning retractor assembly of claim 1 , wherein the projection is in a form of a separate projection member fixedly mounted to a sidewall of the tube.

14. The seatbelt pretensioning retractor assembly of claim 1 , wherein the projection comprises a plate inserted through a hole defined in a sidewall of the tube.

15. The seatbelt pretensioning retractor assembly of claim 1 , wherein the projection and the recess are located along an inboard portion of the tube.

16. The seatbelt pretensioning retractor assembly of claim 1 , wherein the projection and the recess are located along an outboard portion of the tube.

17. The seatbelt pretensioning retractor assembly of claim 1 , wherein the stopper is a circumferential shape that generally matches the internal circumferential shape of the tube.

18. The seatbelt pretensioning retractor assembly of claim 1 , wherein the seal member expands circumferentially outward in response to backpressure from the constriction portion during the actuation of the gas generator.

19. The seatbelt pretensioning retractor assembly of claim 1 , wherein the housing has a guide portion, and wherein the plastically deformable polymer rod is locked against translation in a second direction that is opposite the first direction after the plastically deformable polymer rod has engaged the sprocket to provide pretensioning and/or the plastically deformable polymer rod becomes locked against translation in the second direction that is opposite the first direction during pretensioning due to welding between the plastically deformable polymer rod and the guide portion.

20. A seatbelt pretensioning retractor assembly for use in a passenger vehicle, the seatbelt pretensioning retractor assembly comprising:
a housing adapted for being mounted to a vehicle structure and having an interior cavity;
a tube having an arcuate and curved shape having a first end for fluid communication with a gas generator and a second end in fluid communication with the interior cavity of the housing;
a sprocket rotatably mounted to the housing and fixedly coupled to a spindle adapted for taking up seatbelt webbing during pretensioning, wherein the sprocket has a plurality of vanes;
a driving element comprising a plastically deformable polymer rod configured to extend in a longitudinal direction and having a recessed portion defining a recess that extends generally in the longitudinal direction and a recessed section extending in the longitudinal direction on a side opposite the recessed portion, wherein the plastically deformable polymer rod is disposed within the tube and is translatable through the tube in a first direction toward the sprocket in response to an actuation by the gas generator; and
a seal member disposed between the gas generator and the plastically deformable polymer rod, wherein the tube includes a projection extending within the tube adjacent to the exit to define a constriction portion that has an opening dimension smaller than an inside dimension of adjacent portions of the tube, wherein the recess is aligned with the projection in the first direction and the constriction portion is sized to permit the recessed portion of the plastically deformable polymer rod to pass therethrough, and wherein the recessed section is sized such that a thickness of the plastically deformable polymer rod defined normal to the recessed section is less than a width of the plastically deformable polymer rod defined normal to the thickness to facilitate bending of the plastically deformable polymer rod through the tube during translation in the first direction.

Assignees

• Autoliv Asp Inc

Inventors

• Kohlndorfer Kenneth H
• Hall Christopher D
• Koning Richard
• Koprowicz Chris

Classifications

• B60R2022/4647

  the driving means being a belt, a chain or the like · CPC title

• B60R22/4628 Primary

  characterised by fluid actuators, e.g. pyrotechnic gas generators (actuating a cable B60R22/4619) · CPC title

• B60R22/36

  self-locking in an emergency ({B60R22/3405} , B60R22/343 take precedence) · CPC title

• B60R2022/3402

  Retractor casings; Mounting thereof · CPC title

• B60R2022/4642

  the gas directly propelling a flexible driving means, e.g. a plurality of successive masses, in a tubular chamber · CPC title