Retractable Vehicle Step Assembly with Pivoting Arm and Latch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fixed running boards on motor vehicles often pose practical height issues for users, accumulate dirt and mud, and reduce ground clearance, making them impractical for off-road use.
Innovation Solution
A retractable step assembly with a mounting bracket, arm, drive shaft, pinion, and latch assembly that moves between retracted and extended positions, allowing controlled access and preventing dirt accumulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If fixed running boards are installed to assist user access, then ease of operation is improved, but ground clearance is reduced and the vehicle becomes susceptible to damage during off-road operation
Solution Approach 1:
The step assembly transitions from a fixed structure to a movable one, capable of extending downward to assist user access and retracting upward to maintain ground clearance. The arm pivots between extended and retracted positions, dynamically adapting to different operational conditions (normal driving vs. user access).
Solution Approach 2:
The step assembly is divided into separable components: the step surface, the pivoting arm, and the mounting bracket. This segmentation allows the step to be independently positioned (extended or retracted) without affecting the vehicle's ground clearance during off-road operation.
2Ease of operation
If fixed running boards are installed to assist user access, then ease of operation is improved, but dirt and mud accumulation increases which can be transferred to user clothing
Solution Approach 1:
The step assembly is designed to retract upward away from the ground when not in use, minimizing contact with dirt and mud. The movable nature of the step allows it to be positioned clear of contamination sources, preventing dirt transfer to user clothing while still providing access assistance when extended.
3Reliability
If retractable step assembly is implemented to maintain ground clearance, then reliability is improved, but device complexity increases due to additional moving parts
Solution Approach 1:
A single pivoting arm provides both the extension and retraction functions, eliminating the need for complex motorized or hydraulic systems. The arm's natural pivot motion enables the step to move between positions while maintaining ground clearance, achieving dynamic functionality with minimal mechanical complexity.
4Reliability
If latch assembly is added to retain step in retracted position, then reliability is improved, but device complexity increases
Solution Approach 1:
The latch function is extracted as a separate, simple component that engages with the arm at a specific position. This modular approach allows the latch to be added independently without redesigning the entire mechanism, providing reliable step retention while minimizing additional complexity.
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 retractable step assembly provides adjustable height for easier access, reduces dirt and mud accumulation, and maintains ground clearance for off-road use.
Implementation Method 1
A pinion is operably connected to the drive shaft and rotatable in response to rotation of the drive shaft. A rack link includes a plurality of teeth engaging the pinion. The rack link moves linearly relative to the pinion as the pinion rotates to provide controlled movement of the step between the retracted and extended positions.
Implementation Method 2
an arm having a first end pivotal with respect to the mounting bracket and an opposing second end pivotal with respect to the step for pivotally moving the step between a retracted position and an extended position
Data Source
AI summary
A step assembly is provided for a motor vehicle. The step assembly includes a mounting bracket adapted to be attached to the motor vehicle. The step assembly also includes a step and an arm having a first end pivotal with respect to the mounting bracket and an opposing second end pivotal with respect to the step for pivotally moving the step between a retracted position and an extended position. A latch assembly is coupled to the mounting bracket and operably coupled to the arm. The latch assembly selectively prevents pivotal movement of the arm to retain the step in the retracted position.