Bolt on Push Rod-System

grabcad

This design makes use of a push rod and bell crank to provide a more advantageous motion ratio for the shock and spring. In effect it should round about triple the maximum load (depending on deployment angle); provided none of the existing components fail. This solution simply bolts on to the current system only requiring the addition of 2 holes to the stinger arm. The parts for this solution should be relatively inexpensive consisting mainly of laser cut or pressed steel plates. These additional parts could be sold to customers who already own one of your hand trucks as a DIY kit as it would be relatively easy to retrofit. As is done on the existing product the customer can make minor adjustments to the stinger position by adjusting the pre-load of the spring using the adjuster on the damper. If a more substantial change to the stinger position was required a custom length push-linkage could be laser cut or push-linkages of various lengths could be stocked. Overall I think its a viable solution.