Impact energy absorber with radially adjustable flow metering

Claim 2

An impact energy absorber unit for mounting a bumper assembly to a vehicle body structure comprising first and second cylinders providing first and second fluid chambers therein, 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 cylinder having a cap secured to one end thereof, said cap dividing said cylinders into first and second hydraulic chambers, each of said chambers having oil therein, said cap having a fixed centralized orifice formed therein providing hydraulic communication between said chambers, an elongated metering rod projecting into said orifice and extending longitudinally in said unit, an annular support disc secured to the interior cylindrical wall of said second cylinder adjacent to one end thereof, said support disc having an enlarged central opening therethrough, said metering rod extending through said central opening, said metering rod having an enlarged base member integral therewith which directly covers said central opening, said central opening providing clearance for said metering rod to allow said metering rod to adjust radially with respect to said orifice to meter a predetermined flow of oil from said first chamber to said second chamber in response to the telescoping movement of said first cylinder into said second cylinder.

Claim 3

An impact energy absorber unit for mounting a bumper assembly to a vehicle body structure comprising first and second cylinders providing first and second fluid chambers therein, 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 cylinder having a cap secured to one end thereof, said cap dividing said cylinders into first and second hydraulic chambers, each of said chambers having oil therein, said cap having a fixed centralized orifice formed therein providing hydraulic communication between said chambers, an elongated metering rod projecting into said orifice and extending longitudinally in said unit, an annular support disc secured to the interior cylindrical wall of said second cylinder adjacent to one end thereof, said support disc having an enlarged central opening therethrough, said metering rod extending through said central opening, said metering rod having an enlarged base member integral therewith which directly covers said central opening, said central opening providing clearance for said metering rod to allow said metering rod to adjust radially with respect to said orifice to meter a predetermined flow of oil from said first chamber to said second chamber in response to the telescoping movement of said first cylinder into said second cylinder.

Claim 4

An impact energy absorber unit for mounting a bumper assembly to a vehicle body structure comprising first and second cylinders providing first and second fluid chambers therein, 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 cylinder having a cap secured to one end thereof, said cap dividing said cylinders into first and second hydraulic chambers, each of said chambers having oil therein, said cap having a fixed centralized orifice formed therein providing hydraulic communication between said chambers, an elongated metering rod projecting into said orifice and extending longitudinally in said unit, an annular support disc secured to the interior cylindrical wall of said second cylinder adjacent to one end thereof, said support disc having an enlarged central opening therethrough, said metering rod extending through said central opening, said metering rod having an enlarged base member integral therewith which directly covers said central opening, said central opening providing clearance for said metering rod to allow said metering rod to adjust radially with respect to said orifice to meter a predetermined flow of oil from said first chamber to said second chamber in response to the telescoping movement of said first cylinder into said second cylinder.

Claim 5

An impact energy absorber unit for mounting a bumper assembly to a vehicle body structure 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 cylinder having a cap secured to one end thereof, said cap dividing said cylinders into first and second hydraulic chambers, each of said chambers having a fixed central orifice providing hydraulic communication between said chambers, a molded metering rod of plastic material extending longitudinally in said unit and having one end disposed within said central orifice, a flash shield disposed in said second cylinder, a base plate secured to the other end of said metering pin disposed behind said flash shield, said flash shield having an enlarged central opening therein through which said metering rod extends, said opening being sized to permit said rod to be radially adjusted and aligned with said orifice so that said metering rod and orifice can cooperate to meter fluid from said first chamber into said second chamber in response to the telescoping movement of said cylinders to absorb impact energy applied to said bumper assembly.

Claim 6

An impact energy absorber unit for mounting a bumper assembly to a vehicle body structure 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 cylinder having a cap secured to one end thereof, said cap dividing said cylinders into first and second hydraulic chambers, each of said chambers having a fixed central orifice providing hydraulic communication between said chambers, a molded metering rod of plastic material extending longitudinally in said unit and having one end disposed within said central orifice, a flash shield disposed in said second cylinder, a base plate secured to the other end of said metering pin disposed behind said flash shield, said flash shield having an enlarged central opening therein through which said metering rod extends, said opening being sized to permit said rod to be radially adjusted and aligned with said orifice so that said metering rod and orifice can cooperate to meter fluid from said first chamber into said second chamber in response to the telescoping movement of said cylinders to absorb impact energy applied to said bumper assembly.

Claim 7

An impact energy absorber unit for mounting a vehicle bumper assembly to a vehicle body structure separate from said bumper assembly 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 cylinder having a cap secured to one end thereof, said cap dividing said first and second cylinders into first and second hydraulic chambers, each of said chambers having a hydraulic fluid therein, said cap having a fixed central orifice formed directly therethrough providing communication between said chambers, an elongated metering rod of molded plastic material extending in said unit and having a free end extending into said orifice, an annular base member integral with the other end of said rod, said base member having an outer ring portion peripherally engaging the inside wall of said second cylinder and an annular thin walled portion connecting said outer ring portion to said other end of said rod to permit said rod to radially adjust with respect to said orifice to permit the free end of said rod to coact and progressively restrict said orifice to meter fluid from said first chamber into said second chamber to absorb impact energy applied to said bumper assembly in response to the telescoping of said first cYlinder into said second cylinder.

Claim 8

An impact energy absorber unit for mounting a vehicle bumper assembly to a vehicle body structure separate from said bumper assembly 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 cylinder having a cap secured to one end thereof, said cap dividing said first and second cylinders into first and second hydraulic chambers, each of said chambers having a hydraulic fluid therein, said cap having a fixed central orifice formed directly therethrough providing communication between said chambers, an elongated metering rod of molded plastic material extending in said unit and having a free end extending into said orifice, an annular base member integral with the other end of said rod, said base member having an outer ring portion peripherally engaging the inside wall of said second cylinder and an annular thin walled portion connecting said outer ring portion to said other end of said rod to permit said rod to radially adjust with respect to said orifice to permit the free end of said rod to coact and progressively restrict said orifice to meter fluid from said first chamber into said second chamber to absorb impact energy applied to said bumper assembly in response to the telescoping of said first cYlinder into said second cylinder.