US 5,129,680 A · Preloader sensor and mechanism for securing webbing retractor

Abstract

A preloader sensor which is applied to a webbing retractor for winding a webbing for constraining a vehicle passenger, onto a winding shaft in a stratified arrangement, in order to activate operation of a preloader for tightly holding each passenger with the webbing immediately upon instantaneous detection of rapid deceleration of vehicle speed. The preloader sensor comprises the following; a sensor unit incorporating a mechanism for detecting rapid deceleration of vehicle speed; a releasing member which causes a mass-substance receptive member to enter into a displaceable or an undisplaceable condition, this releasing member causing the mass-substance receiving member to enter into a displaceable, operation capable condition only when the releasing member is moved to a specific position as a result of receiving a predetermined amount of pressure from a fastened bolt, and causing the mass-substance receiving member to move into an undisplaceable condition when the releasing member is moved to a specific position free of pressure from the fastened bolt, and further, this releasing member being capable of moving from one to the other of the pressure-affected position and the pressure-free position; and an energizing means which constantly exerts a force on the releasing and causes it to move when it is at the position free of the pressure of the fastened bolt. Thus, the preloader sensor is reliably prevented from operating under any conditions except for that in which the webbng retractor is perfectly secured to the vehicle body, by virtue of the bolt being screwed in a predetermined amount.

Claims21

Dependent claims

A preloader sensor which is applied to a webbing retractor for winding a webbing for constraining a vehicle passenger onto a winding shaft in stratified form in order to tightly constrain a passenger with said webbing instantaneously upon detecting quickly decelerating vehicle speed, comprising;

a sensor unit which incorporates a mechanism for detecting quickly decelerating vehicle speed;
a releasing means which is displaceably installed so as to be adjustable by the application of external force, to enable and disable said sensor unit for detecting decelerating vehicle speed, based on the predetermined amount of displacement;
and
an urging means which constantly urges said releasing means towards a specific position in which said releasing means cannot execute detection of vehicle speed.

1 more element

A preloader sensor which is applied to a webbing retractor for winding a webbing for constraining a vehicle passenger onto a winding shaft in stratified form in order to activate operation of a preloader for tightly constraining a passenger with said webbing upon instantaneously detecting quickly decelerating vehicle speed, comprising;

a sensor unit which incorporates a mechanism for detecting quickly decelerating vehicle speed, said mechanism incorporating a mass substance and a mass-substance receiving member capable of receiving displaced mass substance and detecting quickly decelerating vehicle speed as a result of displacement of the position of said mass substance receptive member which takes place simultaneously with quick deceleration of the vehicle speed;
a releasing means which causes said mass-substance receiving member to enter into a displaceable condition and an undisplaceable condition, wherein said releasing means causes said mass-substance receiving member to enter into said displaceable condition when said releasing means is moved to a specific position as a result of receiving a predetermined amount of external pressure, in order to make said mass-substance receiving member operative unless and until said releasing means is returned to a position free of external pressure, and said releasing means is movable from one to the other of a pressure-receiving position and a pressure-absent position;
and
an energizing means which constantly exerts a force on said releasing means and moves said releasing means when said releasing means is at said pressure absent position free of said external pressure.

1 more element

A mechanical structure for securing a webbing retractor to a vehicle body, wherein said webbing retractor incorporates a preloader sensor which activates operation of a preloader for tightly constraining a vehicle passenger with a webbing when vehicle speed quickly decelerates, wherein said mechanical structure comprises;

a joining means which joins said webbing retractor to a vehicle body;
and
a releasing means which is disposed in said preloader sensor, for causing said preloader sensor to enter into an operation-incapable condition and an operation capable condition, wherein said preloader sensor enters into said operation-capable condition only when said webbing retractor is joined to the vehicle body by said joining means, whereas said preloader sensor enters into said operation-incapable condition when said webbing retractor and the vehicle body are not joined by said joining means.

Dependencies are inferred from the claim text.

Preloader sensor and mechanism for securing webbing retractor

Life of this patent

Preloader sensor and mechanism for securing webbing retractor

Life of this patent

Abstract

Claims21