Seatbelt pretensioning retractor assembly including a pretensioner rod

Patent metadata

Field	Value
Publication number	US-10328895-B2
Application number	US-201715461534-A
Country	US
Kind code	B2
Filing date	Mar 17, 2017
Priority date	Mar 17, 2017
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

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 polymer rod with a recessed portion. A stopper is coupled to an end portion of the polymer rod. 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 polymer rod to pass therethrough while preventing the stopper from passing therethrough. The polymer rod has a retention feature for releasably engaging the projection.

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 a seatbelt webbing during a pretensioning;
a driving element comprising a polymer rod having a proximal end portion that is disposed towards the gas generator and a distal end portion that is opposite the proximal end portion, and is configured to extend in a longitudinal direction from the proximal end portion to the distal end portion, wherein the polymer rod has a recessed portion defining a recess that extends generally in the longitudinal direction, and wherein the 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 the proximal end portion of the 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 an exit at the second end 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 polymer rod to pass therethrough while preventing the stopper from passing therethrough, and wherein the polymer rod has a retention feature that is disposed at or proximate the distal end portion and that is configured to releasably engage the projection to facilitate retaining or positioning the polymer rod in the tube.

2. The seatbelt pretensioning retractor assembly of claim 1 , wherein the retention feature is configured to release from the projection in response to the actuation by the gas generator.

3. The seatbelt pretensioning retractor assembly of claim 1 , wherein the retention feature is disposed in the recessed portion.

4. The seatbelt pretensioning retractor assembly of claim 1 , wherein the distal end portion of the polymer rod has a distal-most end portion and the recessed portion extends to the distal-most end portion.

5. The seatbelt pretensioning retractor assembly of claim 1 , wherein the distal end portion of the polymer rod has a distal-most end portion and includes at least one chamfer that tapers inwardly along a length of the distal-most end portion in the first direction.

6. The seatbelt pretensioning retractor assembly of claim 5 , wherein the at least one chamfer includes a first chamfer that is disposed on a same side of the polymer rod as the recess.

7. The seatbelt pretensioning retractor assembly of claim 6 , wherein the at least one chamfer includes a second chamfer that is disposed on a side of the polymer rod opposite the first chamfer.

8. The seatbelt pretensioning retractor assembly of claim 1 , wherein the retention feature is configured as a negative feature that is formed into the polymer rod for receiving the projection.

9. The seatbelt pretensioning retractor assembly of claim 8 , wherein the negative feature is configured as a second recess, or a notch, or a hook that is formed into the polymer rod.

10. The seatbelt pretensioning retractor assembly of claim 1 , wherein the distal end portion of the polymer rod has a distal-most end, and wherein the retention feature is spaced apart from the distal-most end of the polymer rod.

11. The seatbelt pretensioning retractor assembly of claim 1 , wherein the polymer rod has a recessed section extending in the longitudinal direction on a side opposite the recessed portion, wherein the recessed section is sized such that a thickness of the polymer rod defined normal to the recessed section is less than a width of the polymer rod defined normal to the thickness to facilitate bending of the polymer rod in directions substantially normal to the recessed section during translation in the first direction.

12. The seatbelt pretensioning retractor assembly of claim 1 , wherein the polymer rod has a positive feature extending generally in the longitudinal direction and the stopper has a negative feature that receives the positive feature to fixedly couple the stopper to the polymer rod.

13. The seatbelt pretensioning retractor assembly of claim 12 , wherein the positive feature has one or more ribs extending therefrom to facilitate retaining the stopper to the polymer rod.

14. The seatbelt pretensioning retractor assembly of claim 1 , wherein the recessed portion of the polymer rod has a proximal end section that is adjacent to the stopper and that includes a chamfered end wall that flares outwardly along a length of the proximal end section in a direction towards the stopper for engagement with the projection during the pretensioning.

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

16. The seatbelt pretensioning retractor assembly of claim 1 , wherein the proximal end portion of the polymer rod has a first outer perimeter and the stopper abuts the proximal end portion and has a second outer perimeter that substantially matches the first outer perimeter.

17. 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 a seatbelt webbing during pretensioning;
a driving element comprising a polymer rod having a proximal end portion that is disposed towards the gas generator and a distal end portion that is opposite the proximal end portion, and is configured to extend in a longitudinal direction from the proximal end portion to the distal end portion, wherein the polymer rod has a recessed portion defining a recess that extends generally in the longitudinal direction, and wherein the 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 the proximal end portion of the 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 an exit at the second end 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 polymer rod to pass therethrough while preventing the stopper from passing therethrough, and wherein the recessed portion of the polymer rod has a proximal end section that is adjacent to the stopper and that includes a chamfered end wall that flares outwardly along a length of the proximal end section in a direction towards the s

Assignees

• Autoliv Asp Inc

Inventors

• Kohlndorfer Kenneth Herbert
• Hall Christopher D
• Koning Richard William
• Wang Bin

Classifications

• B60R2022/4642

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

• B60R2022/3402

  Retractor casings; Mounting thereof · CPC title

• B60R22/4628 Primary

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

• B60R22/28

  incorporating energy-absorbing devices {(belt anchors provided with energy-absorbing means for protecting the occupants in case of physical contact therewith B60R21/055; belt retractors comprising energy-absorbing means B60R22/341, B60R22/4676)} · CPC title