Seat belt retractor with tension relief mechanism
First Claim
1. A safety belt retractor comprising:
- first biasing means for exerting a retractive tensile force on a safety belt webbing such that said belt webbing is urged toward a stored position within said retractor;
second biasing means for generating a counteractive force in opposition to said retractive force such that a vehicle occupant may vary the magnitude of said counteractive force between a minimum value for establishing a maximum tension on said belt webbing and a maximum value for establishing a minimum tension on said belt webbing;
clutch means for limiting said maximum value of said counteractive force generated by said second biasing means to inhibit over-loading thereof; and
actuation means operable in response to the withdrawal of a predetermined length of said belt webbing for selectively causing said counteractive force to be exerted on said belt webbing for reducing the tension exerted thereon by said first biasing means.
9 Assignments
0 Petitions
Accused Products
Abstract
The present invention is directed to a tension relief mechanism for a safety belt retractor that can be selectively actuated for adjusting the tension exerted on the safety belt. The tension relief mechanism is operable for permitting the seat occupant to selectively vary the loading exerted on a counterspring for counteracting the retractive biasing exerted on the safety belt by the retractor rewind spring. The tension relief mechanism is actuated in response to withdrawal of a predetermined length of the safety belt. Thereafter, the withdrawal and subsequent retraction of an additional incremental length of the safety belt causes loading to be exerted on the counterspring. Thus, the residual tension exerted on the safety belt by the retractor is proportional to the magnitude of the loading applied to the counterspring which, in turn, is proportional to the incremental length of additional safety belt withdrawn following actuation of the tension relief mechanism.
-
Citations
40 Claims
-
1. A safety belt retractor comprising:
-
first biasing means for exerting a retractive tensile force on a safety belt webbing such that said belt webbing is urged toward a stored position within said retractor; second biasing means for generating a counteractive force in opposition to said retractive force such that a vehicle occupant may vary the magnitude of said counteractive force between a minimum value for establishing a maximum tension on said belt webbing and a maximum value for establishing a minimum tension on said belt webbing; clutch means for limiting said maximum value of said counteractive force generated by said second biasing means to inhibit over-loading thereof; and actuation means operable in response to the withdrawal of a predetermined length of said belt webbing for selectively causing said counteractive force to be exerted on said belt webbing for reducing the tension exerted thereon by said first biasing means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A safety belt retractor comprising:
-
a rotatable spool for storing safety belt webbing thereon; rewind spring means for exerting a retractive force on said spool to exert tension on said safety belt webbing; and a tension relief mechanism for selectively reducing the tension exerted on said belt webbing by said rewind spring means, said tension relief mechanism having counterspring means for generating a counteractive force in opposition to said retractive force such that a vehicle occupant may vary the magnitude of said counteractive force between a minimum value and a maximum value, and actuation means operable for establishing a non-actuated mode wherein only said retractive force of said rewind spring means is exerted on said spool, and an actuated mode wherein said counteractive force of said counterspring means is applied to said spool in opposition to said retractive force for reducing the tension on said belt webbing in proportion to the magnitude of said counteractive force, and wherein said actuation means is shifted from said non-actuated mode to said actuated mode in response to the withdrawal of a predetermined length of said safety belt. - View Dependent Claims (14, 15, 16, 17, 18, 19)
-
-
20. A tension relief mechanism for use with a safety belt retractor of the type having a rotatable spool for storing safety belt webbing thereon and a rewind spring for exerting a retractive force on the belt webbing, said tension relief mechanism comprising:
-
a counterspring means for generating a counteractive force in opposition to the retractive force such that a vehicle occupant may vary the magnitude of said counteractive force between a minimum value for establishing a maximum tension on said belt webbing and a maximum value for establishing a minimum tension on said belt webbing; and actuation means operable for establishing a non-actuated mode wherein only the retractive force of the rewind spring is exerted on the spool, and an actuated mode wherein said counteractive force of said counterspring means is applied to the spool in opposition to the retractive force for reducing the tension exerted on the belt webbing by the rewind spring, and wherein said actuation means is shifted from said non-actuated mode to said actuated mode in response to a predetermined length of the belt webbing being withdrawn from the spool and said actuation mechanism is shifted from said actuated mode to said non-actuated mode in response to retraction of said predetermined length onto the spool. - View Dependent Claims (21, 22, 23, 24, 25, 26)
-
-
27. A tension relief mechanism for use with a safety belt retractor of the type having a rotatable spool and a rewind spring for exerting a retractive force on the spool for winding the safety belt webbing thereon and tensioning the safety belt webbing, said tension relief mechanism comprising:
-
a clutch member capable of rotational movement with respect to the spool; a counterspring coupling the spool and said clutch member and exerting a counteractive force on the spool to oppose said retractive force in response to relative rotation between the spool and said clutch member such that a seated occupant may vary the magnitude of said counteractive force between a minimum value for establishing a maximum tension on the belt webbing and a maximum value for establishing a maximum tension on the belt webbing; and an actuation mechanism having engaging means moveable between a first position for engaging said clutch member to permit relative rotation between the spool and said clutch member and a second position for disengaging said clutch member to permit concurrent rotation of the spool and said clutch member, said actuation mechanism being operable to position said engaging means between said first and second positions in response to withdrawal of a predetermined length of the safety belt webbing. - View Dependent Claims (28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40)
-
Specification