초록 ▼

A self-locking telescoping device including an outer tube, an inner tube telescoped into the outer tube having a cone-shaped ramp at an inboard end, and a plurality of metal spheres between the ramp and the outer tube. The metal spheres wedge between the ramp and the outer tube when the inner tube i

A self-locking telescoping device including an outer tube, an inner tube telescoped into the outer tube having a cone-shaped ramp at an inboard end, and a plurality of metal spheres between the ramp and the outer tube. The metal spheres wedge between the ramp and the outer tube when the inner tube is thrust into the outer tube in a collapse direction thereby locking the tubes together. When the thrust is attributable to a severe impact, the spheres plastically deform the outer tube by plowing tracks therein thereby to absorb energy. The self-locking telescoping device further includes an actuator rod, a driver which translates the actuator in the collapse direction and in an expansion direction, a first clutch which translates the inner tube with the actuator rod in the expansion direction, a second clutch which translates the inner tube with the actuator rod in the collapse direction, and a tubular retainer on the actuator rod having a plurality of closed-ended slots around the metal spheres. The closed ends of the slots prevent the spheres from becoming wedged between the ramp and the outer tube when the second clutch translates the inner tube with the actuator rod in the collapse direction.

대표청구항 ▼

[ What is claimed is:] [1.]1. An energy absorber between a motor vehicle body and a bumper bar comprising:a stationary outer tube on the motor vehicle body,an inner tube rigidly attached to the bumper bar and telescoped into the outer tube through a first end of the outer tube and supported on the o

[ What is claimed is:] [1.]1. An energy absorber between a motor vehicle body and a bumper bar comprising:a stationary outer tube on the motor vehicle body,an inner tube rigidly attached to the bumper bar and telescoped into the outer tube through a first end of the outer tube and supported on the outer for translation in an expansion direction and in a collapse direction,a cone-shaped ramp on the inner tube at the inboard end thereof facing an inside cylindrical wall on the outer tube,an annular end wall on the inner tube at a small diameter end of the cone-shaped ramp,a plurality of spheres between the cone-shaped ramp and the inside cylindrical wall on the outer tube cupped against the annular end wall during translation of the inner tube in the expansion direction without interfering with translation of the inner tube in the expansion direction and rolling up the cone-shaped ramp into wedging engagement between the cone-shaped ramp and the inside cylindrical wall on the outer tube at the onset of translation of the inner tube in the collapse direction induced by an impact on the bumper bar,each of the plurality of spheres having a hardness sufficient to plastically deform the outer tube by plowing tracks therein when the impact on the bumper bar exceeds the yield strength of the material from which the outer tube is constructed thereby to convert into work a fraction of the kinetic energy of the impact on the bumper bar,an actuator rod telescoped into the outer tube through a second end of the outer tube and into the inner tube through an inboard end of the inner tube,a drive means on the motor vehicle operable to selectively translate the actuator rod in the expansion direction and in the collapse direction,a first clutch means operable to translate the inner tube as a unit with the actuator rod in the expansion direction,a second clutch means operable to translate the inner tube as a unit with the actuator rod in the collapse direction, anda tubular retainer on the actuator rod having a plurality of slots around respective ones of the plurality of spheres each having a closed end adjacent to the corresponding one of the spheres and engageable thereon when the drive means and the second clutch means translate the actuator rod and the inner tube in the collapse direction to prevent the corresponding sphere from rolling up the cone-shaped ramp and becoming wedged between the cone-shaped ramp and the inside cylindrical wall on the outer tube.