Belt clamps for vehicle passenger restraint belts

• US 4,323,204 A
• Filed: 12/26/1979
• Issued: 04/06/1982
• Est. Priority Date: 05/30/1978
• Status: Expired due to Term

• Current Assignee: Juichiro Takada
• Original Assignee: Juichiro Takada
• Inventors: Takada, Juichiro
• Primary Examiner(s): Jillions, John M.
• Application Number:
  US06/107,161
• Time in Patent Office: 832 Days
• Field of Search: 242/107.2, 242/107.4 R-107.4 E, 280/801-803, 280/806-808, 297/468-480, 188/65.1-65.5
• US Class Current: 242/381.4
• CPC Class Codes: B60R 22/1855 the means being sensitive to belt tension
• 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 belt clamp for use in a vehicle passenger restraint belt system comprises a pair of jaws, one of which is movable relative to the other, such as by a lever, is normally held away from the other by a spring, and is moved toward the other in response to an abnormally high pull-out force on the belt to engage a restraint belt guided between the jaws. A multiplicity of spaced-apart, elongated straight teeth oriented widthwise of the belt and of uniform, smoothly curved cross section frictionally clamp the belt against pulling out by tucking loops of the belt into complementary recesses in the other jaw. Preferably, both jaws have substantially identical teeth and substantially identical recesses which are generally complementary to the teeth, the shapes of the teeth and recesses being such as to produce a smoothly corrugated clamping section in which several loops of the belt are formed and by which frictional holding forces are developed without any cutting or abrading of the belt. Advantageously, small variations in gripping faces of the jaws compensate for variations in the properties of the belt (e.g., thickness, density and elasticity) and for deformation of the jaws.

Claims

1. A belt clamp for a vehicle occupant restraint system which includes a restraint belt and a belt retractor onto and from which the belt is selectively wound and unwound and having a pair of jaws, one on either side of the belt, mounted on a lever which is mounted to pivot about an axis spaced apart from the jaws, one of the jaws being mounted on the lever for movement toward the other jaw, in that there is a spring urging the movable jaw in a direction away from the other jaw and in that there is a fixed abutment positioned to be engaged by the movable jaw upon pivoting of the lever in response to a high pull-out force on the belt, thereby to move the movable jaw into engagement with the other jaw, at least one of the jaws having a multiplicity of closely spaced teeth lying transversely to the direction of movement of the belt, each tooth being of generally uniform cross section along its length in the transverse direction, and the other jaw having a multiplicity of recesses, each of which generally matches a corresponding tooth on the other jaw and receives such corresponding tooth and a widthwise strip of the belt upon engagement of the belt between the jaws, each such strip of the belt being formed into a smoothly curved loop by being tucked by a tooth into a corresponding recess of the other jaw and being gripped under pressure between opposed gripping surfaces of the teeth and recesses.

5. A belt clamp according to any of claims 1, 2, 3, or 4 and further characterized in that each recess in said other jaw is a generally straight elongated concavity having a length in the transverse direction of the belt not substantially less than the width of the belt and a generally uniform cross section along its length generally complementary to that of the corresponding tooth of said one jaw, such that each loop is clamped between the surfaces of each tooth and corresponding recess upon engagement of the belt between the jaws.

2. A belt clamp for a vehicle occupant restraint system which includes a restraint belt and a belt retractor onto and from which the belt is selectively wound and unwound and having a pair of jaws, one on either side of the belt, at least one of which is mounted to move toward and away from the other in response to a high pull-out force on the belt characterized in that at least one of the jaws has a multiplicity of closely spaced teeth lying transversely to the direction of movement of the belt, each tooth being generally straight, being of a length not less than the width of the belt, being smoothly curved in end profile, and being of lesser height in portions adjacent the edges of the jaw than in the center portion, and the other jaw having a multiplicity of recesses, each of which generally matches a corresponding tooth on the other jaw and receives such corresponding tooth and a widthwise strip of the belt upon engagement of the belt between the jaws, each such strip of the belt being formed into a smoothly curved loop by being tucked by a tooth into a corresponding recess of the other jaw and being gripped under pressure between opposed gripping surfaces of the teeth and recesses.

3. A belt clamp for a vehicle occupant restraint system which includes a restraint belt and a belt retractor onto and from which the belt is selectively wound and unwound and having a pair of jaws, one on either side of the belt, at least one of which is mounted to move toward and away from the other in response to a high pull-out force on the belt characterized in that at least one of the jaws has a multiplicity of closely spaced teeth lying transversely to the direction of movement of the belt, each tooth being generally straight, being of a length not less than the width of the belt, being smoothly curved in end profile, and being of maximum height at the center and of gradually reduced height moving from the center toward each side, and the other jaw having a multiplicity of recesses, each of which generally matches a corresponding tooth on the other jaw and receives such corresponding tooth and a widthwise strip of the belt upon engagement of the belt between the jaws, each such strip of the belt being formed into a smoothly curved loop by being tucked by a tooth into a corresponding recess of the other jaw and being gripped under pressure between opposed gripping surfaces of the teeth and recesses.

4. A belt clamp for a vehicle occupant restraint system which includes a restraint belt and a belt retractor onto and from which the belt is selectively wound and unwound and having a pair of jaws, one on either side of the belt, at least one of which is mounted to move toward and away from the other in response to a high pull-out force on the belt characterized in that at least one of the jaws has a multiplicity of closely spaced teeth lying transversely to the direction of movement of the belt, each tooth being generally straight, being of a length not less than the width of the belt, being smoothly curved in end profile, and being of generally uniform cross section along its length in the transverse direction, and the other jaw having a multiplicity of recesses, each of which generally matches a corresponding tooth on the other jaw and receives such corresponding tooth and a widthwise strip of the belt upon engagement of the belt between the jaws, the clamping surface of at least one of the jaws being transversely cambered, the teeth and recesses being concavely curved in a direction transverse to the axis of the belt to compensate for deflection of the jaw when the belt is clamped between the jaws, each such strip of the belt being formed into a smoothly curved loop by being tucked by a tooth into a corresponding recess of the other jaw and being gripped under pressure between opposed gripping surfaces of the teeth and recesses.

6. A belt clamp for a vehicle passenger restraint belt system comprising a frame having a pair of spaced-apart sides, a base and pair of jaws, the first jaw being fixedly mounted between the spaced-apart sides and adjacent the base;

a roller having a corrugated surface slidably received in a pair of slots in the frame sides for movement between a releasing position and clamping position;

a clamp member defining a second jaw movably mounted between the frame sides adjacent the roller and having a wedge surface which is corrugated and oblique to the path of the belt and engaged by the roller and coacting therewith such that the second jaw on the clamp member is wedged toward the fixed first jaw by the roller upon movement of the roller toward the clamping position;

cooperating guide means on the clamp member and the frame for guiding the clamp member toward and away from the base in a direction oblique to the base, the clamp member being movable in a directon toward the release position of the roller at the same time that it moves away from the base;

a spring urging the roller toward the release position; and

the clamp member being urged in a direction toward the roller by the force of gravity, whereby both the clamp member and roller are normally urged toward releasing positions such that a belt led between the fixed first jaw and the second jaw on the clamp member and thence around the roller and away from the roller in a direction exerting a force on the roller in a direction toward the clamping position is free to move through the belt clamp, and whereby a high pull-out force on the belt shifts the roller toward the clamping position and clamps the belt between the fixed first jaw member and the second jaw on the clamp member by a combination of the wedging action of the clamp member and the guiding action of the guide means.

7. A belt clamp according to claim 6, wherein the clamp member is a lever pivotally mounted between the frame sides having a wedge surface oblique to the path of the belt, and further comprising a spring urging the lever toward the releasing position.