Tailgate Friction Damper Resolves Free-Fall Impact
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tailgate counterbalancing hinge designs fail to adequately de-accelerate the tailgate during opening, leading to potential injury and damage from sudden drops or impacts on supports.
Innovation Solution
A tailgate counterbalancing hinge assembly that utilizes friction by incorporating a pivot body with slits, which deflects to create increasing friction as the torque rod twists, slowing the tailgate's opening motion through a progressively increasing braking effect.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a torque rod based tailgate counter balancing hinge assembly is used to reduce lifting effort, then the effort required to raise and lower the tailgate is reduced, but the tailgate can cause objectionable impact on supports or injury to operators due to residual kinetic energy during free fall
Solution Approach 1:
The patent converts the harmful residual kinetic energy and free fall motion into a beneficial controlled deceleration process. The friction damper assembly transforms the unwanted impact energy into frictional heat, gradually slowing the tailgate from its accelerated motion to a controlled stop, thereby eliminating the harmful impact while maintaining the counterbalancing benefit.
Solution Approach 2:
The friction damper assembly acts as an intermediary element between the tailgate and the hinge assembly. This intermediary component absorbs and dissipates the excess kinetic energy through friction, mediating between the counterbalancing force and the tailgate's motion to prevent harmful impacts on supports and operators.
2Ease of operation
If the tailgate is allowed to free fall during opening to reduce lifting effort, then opening effort is minimized, but the tailgate drops quickly causing injury risk and potential damage
Solution Approach 1:
The friction damper provides continuous periodic resistance throughout the tailgate's opening motion. As the tailgate moves through its range of motion, the friction element continuously applies a retarding force, creating a periodic deceleration effect that controls the speed throughout the entire opening sequence rather than allowing uncontrolled free fall.
Solution Approach 2:
The friction damper changes the motion parameters of the tailgate by introducing friction-based resistance. This alters the velocity and acceleration profiles during opening, transforming the rapid free fall motion into a controlled, gradually decelerating motion that maintains safety while preserving ease of operation.
3Object-affected harmful factors
If a friction damper assembly is added to control tailgate speed, then impact and injury risk are reduced, but device complexity increases
Solution Approach 1:
The friction damper assembly is merged with the existing hinge assembly structure. The damper components are integrated into the hinge's end assemblies, sharing mounting points and structural elements with the counterbalancing mechanism. This merging approach adds the safety function while minimizing the increase in overall device complexity.
Solution Approach 2:
The hinge assembly is designed with multi-functionality, where the same structural components serve both the counterbalancing function and the friction damping function. The end assemblies and mounting structures are utilized for both torque rod attachment and friction damper mounting, allowing one system to perform multiple safety and support functions simultaneously.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively slows the tailgate's free fall, reducing the risk of injury and damage by ensuring a gradual stop at the open position, thereby enhancing safety and preventing over-travel.
Implementation Method 1
the outward deflection of the split wall part increases, thereby creating greater friction between an outer surface of the split wall part and an inner surface of the cylindrical chamber within the bushing that receives the pivot body. As the torque rod is twisted further due to the tailgate being opened further, the outward deflection of the split wall part increases, thereby creating greater friction between an outer surface of the split wall part and an inner surface of the cylindrical chamber
Implementation Method 2
a linear torque rod, a first end assembly that pivotally retains the tailgate while permitting the torque rod to be rigidly coupled to the tailgate for movement with the tailgate about a pivot axis... the torque rod is twisted, thereby creating torque within the rod. The torque is then transferred to the pivot body
Data Source
AI summary
A tailgate counterbalancing hinge assembly includes a linear torque rod, a first end assembly and a second end assembly secured to the torque rod. A first end assembly pivotally supports the tailgate while permitting a torque rod end to be rigidly coupled to the tailgate for movement with the tailgate about a pivot axis. A second end assembly also pivotally supports the tailgate and permits the other end of the torque rod to be rigidly connected to the vehicle body. The first end assembly includes a bushing and split pivot body rotatably mounted within the bushing that creates increasing friction between the split pivot body and the bushing as the torque rod is twisted due to the tailgate being opened. The increasing friction creates a progressively increasing braking or dampening effect, which slows the free fall of the tailgate as it is opened.