ThruBolt Hinge Attachment System

• Novel bolting system results in an average overall door/ hinge/ pillar system stiffness increase of 30%
• Negligible weight penalty
• Negligible cost impact
• Significantly simplifies through pillar hinge attachment

This proprietary fastening strategy was developed by Multimatic to significantly improve joint stiffness without increasing cost or weight. This system utilizes a unique bolt with two thread diameters and a leading end, self cutting feature that achieves a "through bolted" joint without the requirement of a spacer and its associated complexity. Joint stiffness increases of up to 30% have been realized with the adoption of this strategy.

As the large diameter threaded portion of the fastener engages and advances into the tapping plate, the hardened, self-tapping, leading end cuts into the opposite pillar section. Once complete the larger diameter, threaded section, under the head maintains the required clamping load in a conventional manner while the self-cutting threaded section creates a through bolted joint by fully engaging the opposite pillar panel.

This fastening strategy is currently utilized on the Chrysler Prowler and is under consideration by numerous other new programs.