Polymer, energy absorber rail extension, methods of making and vehicles using the same

A vehicle, comprising,

• a bumper beam;
• a vehicle rail;
• a rail extension comprising
• an energy absorber comprising a polymer body, wherein the energy absorber comprises cells formed by cell walls extending a length of the energy absorber and forming cavities therethrough;
• each side of the energy absorber comprises an open channel, wherein the channels are defined by walls of adjacent cells;
• and
• a vehicle attachment tab extending from one of the cell walls at a rail end of the energy absorber and attached to the vehicle rail, and a bumper attachment tab extending from one of the cell walls at another end of the energy absorber and attached to the bumper beam;
• a first vehicle attachment tab gusset extending between the vehicle attachment tab and the cell wall on one side of an opening in the vehicle attachment tab and a second vehicle attachment tab gusset extending between the vehicle attachment tab and the cell wall on an opposite side of the opening in the vehicle attachment tab from the first vehicle attachment tab gusset;
• and
• a first bumper attachment tab gusset extending between the bumper attachment tab and the cell wall on one side of an opening in the bumper attachment tab and a second bumper attachment tab gusset tab gusset extending between the bumper attachment tab and the cell wall on an opposite side of the opening in the bumper attachment tab from the first bumper attachment tab gusset;
• wherein the energy absorber, the vehicle attachment tab and the bumper attachment tab, the first vehicle attachment tab gusset, the second vehicle attachment tab gusset, first bumper attachment tab gusset, and the second bumper attachment tab gusset were formed as one-piece.

A method of controlling a crushing of a vehicle extension, comprising:

• determining an initial force peak during crushing of the energy absorber;
• beveling a surface of some cells based upon the initial force peak;
• and
• changing the angle of the bevel until the initial force peak is less than a desired maximum force;
• forming a one-piece rail extension, the rail extension comprising
• an energy absorber comprising a polymer body, wherein the energy absorber comprises cells formed by cell walls extending a length of the energy absorber and forming cavities therethrough, wherein some of the cells comprise the bevel;
• a vehicle attachment tab extending from one of the cell walls at one end of the energy absorber;
• a bumper attachment tab extending from one of the cell walls at another end of the energy absorber;
• and
• open channels along the outside of the rail extension;
• a first vehicle attachment tab gusset extending between the vehicle attachment tab and the cell wall on one side of an opening in the vehicle attachment tab and a second vehicle attachment tab gusset extending between the vehicle attachment tab and the cell wall on an opposite side of the opening in the vehicle attachment tab from the first vehicle attachment tab gusset;
• a first bumper attachment tab gusset extending between the bumper attachment tab and the cell wall on one side of an opening in the bumper attachment tab and a second bumper attachment tab gusset tab gusset extending between the bumper attachment tab and the cell wall on an opposite side of the opening in the bumper attachment tab from the first bumper attachment tab gusset;
• and
• wherein the energy absorber, the vehicle attachment tab, and the bumper attachment tab, the first vehicle attachment tab gusset, the second vehicle attachment tab gusset, first bumper attachment tab gusset, and the second bumper attachment tab gusset were formed as one-piece.