Telescoping energy absorbing unit

Claim 2

An impact energy absorbing unit for mounting a bumper assembly to a support on an automotive vehicle comprising: first and second cylinders, support means mounting said first cylinder for telescopic movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, said first cylinder having cap means fixed at one end thereof and slidably disposed in said second cylinder to provide variable volume first and second fluid chambers in said unit, a hydraulic fluid in said first and second chambers, an opening through said cap hydraulically communicating said first and second chambers, a fluid amplifier supported by said cap having an orifice therethrough aligned with said opening in said cap, said fluid amplifier having channel means extending at an angle with respect to said orifice to direct fluid at a predetermined angle relative to the axis of said orifice to regulate the flow through said orifice in proportion to the velocity of the inner cylinder when telescoping into said outer cylinder in response to an impact load applied to the bumper assembly whereby the energy of the impact load is dissipated.

Claim 3

An impact energy absorbing unit for mounting a bumper assembly to a support on an automotive vehicle comprising: first and second cylinders, support means mounting said first cylinder for telescopic movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, said first cylinder having cap means fixed at one end thereof and slidably disposed in said second cylinder to provide first and second fluid variable volume chambers in said unit, a hydraulic fluid in said chambers, a centralized opening in said cap hydraulically communicating said first and second chambers, a unitary fluid amplifying member supported by said cap having a central orifice aligned with said central opening of said cap, said fluid amplifier member having radial channel means extending at an angle with respect to said central orifice and providing passage means to direct hydraulic fluid at a predetermined angle relative to the axis of said orifice and said opening to control the flow of hydraulic fluid through said orifice from said first to said second chambers in proportion to the velocity of the first cylinder when telescoping into said second cylinder in response to an impact load applied to the bumper assembly so that the pressure in said first chamber remains at a substantially constant pressure substantially throughout the stroke of said first cylinder, and spring means for moving said first cylinder back to said extended position after removal of said impact load.

Claim 4

An impact energy absorbing unit for mounting a bumper assembly to a support on an automotive vehicle comprising: first and second cylinders, support means mounting said first cylinder for telescopic movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, said first cylinder having cap means fixed at one end thereof and slidably disposed in said second cylinder to provide first and second fluid variable volume chambers in said unit, a hydraulic fluid in said chambers, a centralized opening in said cap hydraulically communicating said first and second chambers, a unitary fluid amplifying member supported by said cap having a central orifice aligned with said central opening of said cap, said fluid amplifier member having radial channel means extending at an angle with respect to said central orifice and providing passage means to direct hydraulic fluid at a predetermined angle relative to the axis of said orifice and said opening to control the flow of hydraulic fluid through said orifice from said first to said second chambers in proportion to the velocity of the first cylinder when telescoping into said second cylinder in response to an impact load applied to the bumper assembly so that the pressure in said first chamber remains at a substantially constant pressure substantially throughout the stroke of said first cylinder, and spring means for moving said first cylinder back to said extended position after removal of said impact load.

Claim 5

An impact energy absorbing unit for mounting a bumper assembly to a substantially rigid support on an automotive vehicle comprising first and second cylinders, support means mounting said first cylinder for telescoping movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, spring means in said unit for urging said cylinders to said extended position, said first cylinder having a cap fixed to one end thereof and operatively disposed within said second cylinder to provide first and second hydraulic fluid chambers in said unit having a variable volume, a hydraulic fluid in said first and second chambers, an opening formed through said cap for hydraulically connecting said first and second chambers with each other, a fluid amplifier member supported by said cap having an orifice aligned with said opening in said cap, said fluid amplifier member having fluid channel means therein extending at an angle from said orifice to the periphery of said amplifier member to direct hydraulic fluid at a predetermined angle with respect to the axis of said orifice to regulate the flow of hydraulic fluid through said orifice in proportion to the velocity of the first cylinder telescoping into said cylinder in response to a predetermined impact load applied to said bumper assembly so that the energy of impact is dissipated, flap valve means for closing said opening in said cap subsequent to the absorption of the energy of impact, and fluid bleed means in said flap valve means for bleeding fluid from said second chamber to said first chamber to control the rate that said spring means moves said first cylinder back to said extended position after the impact load is removed.

Claim 6

An impact energy absorbing unit for mounting a bumper assembly to a substantially rigid support on an automotive vehicle comprising first and second cylinders, support means mounting said first cylinder for telescoping movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, spring means in said unit for urging said cylinders to said extended position, said first cylinder having a cap fixed to one end thereof and operatively disposed within said second cylinder to provide first and second hydraulic fluid chambers in said unit having a variable volume, a hydraulic fluid in said first and second chambers, an opening formed through said cap for hydraulically connecting said first and second chambers with each other, a fluid amplifier member supported by said cap having an orifice aligned with said opening in said cap, said fluid amplifier member having fluid channel means therein extending at an angle from said orifice to the periphery of said amplifier member to direct hydraulic fluid at a predetermined angle with respect to the axis of said orifice to regulate the flow of hydraulic fluid through said orifice in proportion to the velocity of the first cylinder telescoping into said cylinder in response to a predetermined impact load applied to said bumper assembly so that the energy of impact is dissipated, flap valve means for closing said opening in said cap subsequent to the absorption of the energy of impact, and fluid bleed means in said flap valve means for bleeding fluid from said second chamber to said first chamber to control the rate that said spring means moves said first cylinder back to said extended position after the impact load is removed.

Claim 7

An impact energy absorbing unit for mounting a bumper assembly to a substantially rigid support on an automotive vehicle comprising first and second cylinders, support means mounting said first cylinder for telescoping movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, variable volume gas spring means in said unit for urging said cylinders to said extended position, said first cylinder having a cap fixed to one end thereof and operatively disposed within said second cylinder to provide first and second variable volume hydraulic fluid chambers in said unit, a hydraulic fluid in said first and second chambers, a centralized opening formed in said cap for hydraulically connecting said first and second chambers with each other, a unitary fluid amplifier supported on one side of said cap having central orifice aligned with said central opening in said cap, said fluid amplifier having radial channel means therein extending from the periphery of said central orifice to direct fluid into said orifice to control the flow of fluid through said orifice in proportion to the velocity of said first cylinder when telescoping into said second cylinder in response to a predetermined impact load applied to said bumper assembly so that pressure in said first cylinder is controlled and impact energy is dissipated at a predetermined rate, flap valve means supported on the other side of said cap for closing said opening when said gas spring means urges said first cylinder back toward said extended position, and bleed means in said flap valve means for bleeding hydraulic fluid from said second chamber back to said first chamber to thereby reduce the rate at which said first cylinder recovers to said extended position.

Claim 8

An impact energy absorbing unit for mounting a bumper assembly to a substantially rigid support on an automotive vehicle comprising first and second cylinders, support means mounting said first cylinder for telescoping movement with respect to said second cylinder between an extended position and a retracted position, said first and second cylinders having cooperating stop means to establish the extended position of said cylinders, variable volume gas spring means in said unit for urging said cylinders to said extended position, said first cylinder having a cap fixed to one end thereof and operatively disposed within said second cylinder to provide first and second variable volume hydraulic fluid chambers in said unit, a hydraulic fluid in said first and second chambers, a centralized opening formed in said cap for hydraulically connecting said first and second chambers with each other, a unitary fluid amplifier supported on one side of said cap having central orifice aligned with said central opening in said cap, said fluid amplifier having radial channel means therein extending from the periphery of said central orifice to direct fluid into said orifice to control the flow of fluid through said orifice in proportion to the velocity of said first cylinder when telescoping into said second cylinder in response to a predetermined impact load applied to said bumper assembly so that pressure in said first cylinder is controlled and impact energy is dissipated at a predetermined rate, flap valve means supported on the other side of said cap for closing said opening when said gas spring means urges said first cylinder back toward said extended position, and bleed means in said flap valve means for bleeding hydraulic fluid from said second chamber back to said first chamber to thereby reduce the rate at which said first cylinder recovers to said extended position.