Locking mechanism for a vehicle restraint belt retractor

Claim 2

In a vehicle occupant restraint belt retractor including a housing adapted to be mounted on a vehicle, a belt reel rotatably mounted on the housing for movement in belt winding and unwinding directions and including locking surfaces spaced circumferentially about the axis of reel rotation, a restraint belt secured to the reel so as to be wound and unwound therefrom during the reel rotation, and a winding spring normally biasing the reel in the belt winding direction, a locking mechanism for the retractor comprising: a locking member pivotally mounted on the housing for movement between a locking position in engagement with one of the reel locking surfaces to prevent belt unwinding and a nonlocking position out of engagement with the reel to allow belt unwinding; an unlocking spring normally biasing the locking member to the nonlocking position with a torque T1; a control member mounted on the housing for movement from a first position to a second position so as to engage the locking member and move the same to the locking position; a clutch arrangement extending between the belt reel and the control member and frictionally clutched to the reel so that belt unwinding urges the control member toward the second position by an effort that tends to move the locking member to the locking position with a torque T2, torque T2 being less than torque T1 so that belt unwinding does not normally move the locking member to the locking position and thereby terminate such unwinding, and the clutching of the reel to the control member tending to move the control member from the second posititon to the first position when the winding spring winds the belt on the reel with the locking member initially in the locking position so that this movement of the control member allows the normal bias of the unlocking spring to move the locking member to the nonlocking position and thereby permits subsequent belt unwinding; a vehicle acceleration or deceleration responsive inertia arrangement mounted relative to the retractor housing and having a movable portion that engages the control member to move this member to the second position in response to abrupt vehicle acceleration or deceleration of a predetermined level and to thereby move the locking member to the locking position against the bias of the unlocking spring, belt unwinding during such vehicle acceleration or deceleration causing the clutch arrangement to cooperate with the inertia arrangement in moving the control member so as to move the locking member to the locking position and this cooperation lessening the level of vehicle acceleration or deceleration necessary to cause the movement of the locking member to the locking position against the bias of the unlocking spring; and overcenter means alternately biasing the control member to either the first or second position by an effort that holds the locking member in the locking position with a torque T3, torque T3 being greater than torque T1 so that the unlocking spring does not move the locking member fRom the locking position to the nonlocking position without the assist of the clutch arrangement as the belt is wound on the reel, and torque T3 being less than the total of torques T1 and T2 so that the unlocking spring and the clutch arrangement act against the overcenter means to move the locking member from the locking position to the nonlocking position as the belt is wound on the reel.

Claim 3

In a vehicle occupant restraint belt retractor including a housing adapted to be mounted on a vehicle, a belt reel rotatably mounted on the housing for movement in belt winding and unwinding directions and including locking surfaces spaced circumferentially about the axis of reel rotation, a restraint belt secured to the reel so as to be wound and unwound therefrom during the reel rotation, and a winding spring normally biasing the reel in the belt winding direction, a locking mechanism for the retractor comprising: a locking member pivotally mounted on the housing for movement between a locking position in engagement with one of the reel locking surfaces to prevent belt unwinding and a nonlocking position out of engagement with the reel to allow belt unwinding; an unlocking spring normally biasing the locking member to the nonlocking position with a torque T1; a control member mounted on the housing for movement from a first position to a second position so as to engage the locking member and move the same to the locking position; a clutch arrangement including a disc frictionally driven by the belt reel, an arcuate pin and slot connection generated about the axis of reel rotation and extending between the housing and the disc to limit the rotation of the disc with respect to the housing, and a link pivoted at one end thereof to the disc and at the other end thereof to the control member so that belt unwinding urges the control member toward the second position by an effort that tends to move the locking member to the locking position with a torque T2, torque T2 being less than torque T1 so that belt unwinding does not normally move the locking member to the locking position and thereby terminate such unwinding, and the clutch arrangement tending to move the control member from the second position to the first position when the winding spring winds the belt on the reel with the locking member initially in the locking position so that this movement of the control member allows the normal bias of the unlocking spring to move the locking member to the nonlocking position and thereby permits subsequent belt unwinding; a vehicle acceleration or deceleration responsive inertia arrangement mounted on the retractor housing and including a movable portion that engages the control member to move this member to the second position in response to abrupt vehicle acceleration or deceleration of a predetermined level and to thereby move the locking member to the locking position against the bias of the unlocking spring, belt unwinding during such vehicle acceleration or deceleration causing the clutch arrangement to cooperate with the inertia arrangement in moving the control member so as to move the locking member to the locking position, and this cooperation lessening the level of vehicle acceleration or deceleration necessary to cause the movement of the locking member to the locking position against the bias of the unlocking spring; and an overcenter spring extending between the control member and the housing to alternately bias the control member to either the first or second position and this spring holding the control member in the second position with an effort that holds the locking member in the locking position with a torque T3, torque T3 being greater than torque T1 so that the unlocking spring does not move the locking member from the locking position to the nonlocking position without the assist of the clutch arrangement as the belt is wound on the reel, and torque T3 being less than the total of torques T1 and T2 so that the unlocking spring and the clutch arrangement act against the overcenter spring to move the locking member from the locking position to the nonlocking position as the belt is wound on the reel.

Claim 4

In a vehicle occupant restraint belt retractor including a housing adapted to be mounted on a vehicle, a belt reel rotatably mounted on the housing for movement in belt winding and unwinding directions and including locking surfaces spaced circumferentially about the axis of reel rotation, a restraint belt secured to the reel so as to be wound and unwound therefrom during the reel rotation, and a winding spring normally biasing the reel in the belt winding direction, a locking mechanism for the retractor comprising: a locking member pivotally mounted on the housing for movement between a locking position in engagement with one of the reel locking surfaces to prevent belt unwinding and a nonlocking position out of engagement with the reel to allow belt unwinding; an unlocking spring normally biasing the locking member to the nonlocking position with a torque T1; a control member mounted on the housing for movement from a first position to a second position so as to engage the locking member and move the same to the locking position; a clutch arrangement including a disc frictionally driven by the belt reel, an arcuate pin and slot connection generated about the axis of reel rotation and extending between the housing and the disc to limit the rotation of the disc with respect to the housing, and a link pivoted at one end thereof to the disc and at the other end thereof to the control member so that belt unwinding urges the control member toward the second position by an effort that tends to move the locking member to the locking position with a torque T2, torque T2 being less than torque T1 so that belt unwinding does not normally move the locking member to the locking position and thereby terminate such unwinding, and the clutch arrangement tending to move the control member from the second position to the first position when the winding spring winds the belt on the reel with the locking member initially in the locking position so that this movement of the control member allows the normal bias of the unlocking spring to move the locking member to the nonlocking position and thereby permits subsequent belt unwinding; a vehicle acceleration or deceleration responsive inertia arrangement mounted on the retractor housing and including a movable portion that engages the control member to move this member to the second position in response to abrupt vehicle acceleration or deceleration of a predetermined level and to thereby move the locking member to the locking position against the bias of the unlocking spring, belt unwinding during such vehicle acceleration or deceleration causing the clutch arrangement to cooperate with the inertia arrangement in moving the control member so as to move the locking member to the locking position, and this cooperation lessening the level of vehicle acceleration or deceleration necessary to cause the movement of the locking member to the locking position against the bias of the unlocking spring; and an overcenter spring extending between the control member and the housing to alternately bias the control member to either the first or second position and this spring holding the control member in the second position with an effort that holds the locking member in the locking position with a torque T3, torque T3 being greater than torque T1 so that the unlocking spring does not move the locking member from the locking position to the nonlocking position without the assist of the clutch arrangement as the belt is wound on the reel, and torque T3 being less than the total of torques T1 and T2 so that the unlocking spring and the clutch arrangement act against the overcenter spring to move the locking member from the locking position to the nonlocking position as the belt is wound on the reel.

Claim 5

In a vehicle occupant restraint belt retractor including a housing adapted to be mounted on a vehicle, a belt reel rotatably mounted on the housing for movement in belt winding and unwinding directions and including locking surfaces spaced circumferentially about the axis of reel rotation, a restraint belt secured to the reel so as to be wound and unwound therefrom during the reel rotation, and a winding spring normally biasing the reel in the belt winding direction, a locking mechanism for the retractor comprising: a locking member pivotally mounted on the housing for movement between a locking position in engagement with one of the reel locking surfaces to prevent belt unwinding and a nonlocking position out of engagement with the reel to allow belt unwinding; an unlocking spring normally biasing the locking member to the nonlocking position with a torque T1; a control member pivotally mounted on the housing for movement from a first position to a second position so as to engage the locking member and move the same to the locking position; a clutch arrangement including a first disc rotatably driven with the belt reel, a second disc axially fixed with respect to the first disc along the axis of reel rotation but rotatable with respect to the first disc, a disc-type spring extending between the first and second discs so as to frictionally clutch the second disc to the reel, an arcuate pin and slot connection generated about the axis of reel rotation and extending between the housing and second disc to limit rotation of the latter with respect to the former, and a link pivoted at one end thereof to the second disc and at the other end thereof to the control member so that belt unwinding urges the control member toward the second position by an effort that tends to move the locking member to the locking position with a torque T2, torque T2 being less than torque T1 so that belt unwinding does not normally move the locking member to the locking position and thereby terminate such unwinding, and the clutch arrangement tending to move the control member from the second position to the first position when the winding spring winds the belt on the reel with the locking member initially in the locking position so that this movement of the control member allows the normal bias of the unlocking spring to move the locking member to the nonlocking position and thereby permits subsequent belt unwinding; a pendulum arrangement mounted on the retractor housing and including a base having a partial spherical seat, a pendulum including a head and a weight with an arm extending therebetween, the pendulum head being seated on the seat of the base so that the arm extends downwardly in a vertical direction to the weight whose inertial force swings the pendulum in response to vehicle acceleration or deceleration in any horizontal direction, and a plunger slidably mounted on the base so as to be moved upwardly by the pendulum head as the pendulum swings, the plunger including a portion which engages the control member as the plunger is moved upwardly and thereby moves the control member to the second position and the locking member to the locking position against the bias of the unlocking spring when the vehicle acceleration or deceleration exceeds a predetermined level, belt unwinding during such vehicle acceleration or deceleration causing the clutch arrangement to cooperate with the pendulum arrangement in moving the control member so as to move the locking member to the locking position, and this cooperation lessening the level of vehicle acceleration or deceleration necessary to cause the movement of the locking member to the locking position against the bIas of the unlocking spring; and a helical spring extending between the control member and the housing so that the longitudinal axis thereof moves overcenter of the axis of control member movement in a manner that alternately biases the control member to either the first or second position and this spring holding the control member in the second position by an effort that holds the locking member in the locking position with a torque T3, torque T3 being greater than torque T1 so that the unlocking spring does not move the locking member from the locking position to the nonlocking position without the assist of the clutch arrangement as the belt is wound on the reel, and torque T3 being less than the total of torques T1 and T2 so that the unlocking spring and the clutch arrangement act against the helical spring to move the locking member from the locking position to the nonlocking position as the belt is wound on the reel.

Claim 6

In a vehicle occupant restraint belt retractor including a housing adapted to be mounted on a vehicle, a belt reel rotatably mounted on the housing for movement in belt winding and unwinding directions and including locking surfaces spaced circumferentially about the axis of reel rotation, a restraint belt secured to the reel so as to be wound and unwound therefrom during the reel rotation, and a winding spring normally biasing the reel in the belt winding direction, a locking mechanism for the retractor comprising: a locking member pivotally mounted on the housing for movement between a locking position in engagement with one of the reel locking surfaces to prevent belt unwinding and a nonlocking position out of engagement with the reel to allow belt unwinding; an unlocking spring normally biasing the locking member to the nonlocking position with a torque T1; a control member pivotally mounted on the housing for movement from a first position to a second position so as to engage the locking member and move the same to the locking position; a clutch arrangement including a first disc rotatably driven with the belt reel, a second disc axially fixed with respect to the first disc along the axis of reel rotation but rotatable with respect to the first disc, a disc-type spring extending between the first and second discs so as to frictionally clutch the second disc to the reel, an arcuate pin and slot connection generated about the axis of reel rotation and extending between the housing and second disc to limit rotation of the latter with respect to the former, and a link pivoted at one end thereof to the second disc and at the other end thereof to the control member so that belt unwinding urges the control member toward the second position by an effort that tends to move the locking member to the locking position with a torque T2, torque T2 being less than torque T1 so that belt unwinding does not normally move the locking member to the locking position and thereby terminate such unwinding, and the clutch arrangement tending to move the control member from the second position to the first position when the winding spring winds the belt on the reel with the locking member initially in the locking position so that this movement of the control member allows the normal bias of the unlocking spring to move the locking member to the nonlocking position and thereby permits subsequent belt unwinding; a pendulum arrangement mounted on the retractor housing and including a base having a partial spherical seat, a pendulum including a head and a weight with an arm extending therebetween, the pendulum head being seated on the seat of the base so that the arm extends downwardly in a vertical direction to the weight whose inertial force swings the pendulum in response to vehicle acceleration or deceleration in any horizontal direction, and a plunger slidably mounted on the base so as to be moved upwardly by the pendulum head as the pendulum swings, the plunger including a portion which engages the control member as the plunger is moved upwardly and thereby moves the control member to the second position and the locking member to the locking position against the bias of the unlocking spring when the vehicle acceleration or deceleration exceeds a predetermined level, belt unwinding during such vehicle acceleration or deceleration causing the clutch arrangement to cooperate with the pendulum arrangement in moving the control member so as to move the locking member to the locking position, and this cooperation lessening the level of vehicle acceleration or deceleration necessary to cause the movement of the locking member to the locking position against the bIas of the unlocking spring; and a helical spring extending between the control member and the housing so that the longitudinal axis thereof moves overcenter of the axis of control member movement in a manner that alternately biases the control member to either the first or second position and this spring holding the control member in the second position by an effort that holds the locking member in the locking position with a torque T3, torque T3 being greater than torque T1 so that the unlocking spring does not move the locking member from the locking position to the nonlocking position without the assist of the clutch arrangement as the belt is wound on the reel, and torque T3 being less than the total of torques T1 and T2 so that the unlocking spring and the clutch arrangement act against the helical spring to move the locking member from the locking position to the nonlocking position as the belt is wound on the reel.