Pinned Torque Box Coupling for Fire Apparatus Maintenance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The complex coupling interface between the torque box and the fire apparatus frame in fire trucks makes maintenance and inspection difficult and time-intensive due to the need for frequent inspection of multiple bolts, which are often located in hard-to-reach areas, leading to increased maintenance time and costs.
Innovation Solution
A fire apparatus design utilizing a pinned connection system with a limited number of pins instead of bolts to couple the torque box to the frame, reducing the number of components that need inspection and eliminating the need for clamp loads, allowing for easier maintenance by confirming pin presence and retainer security.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a bolt-based coupling interface is used to connect the torque box to the fire apparatus frame, then the connection strength and reliability are improved, but the complexity of maintenance and inspection increases due to multiple bolts located in hard-to-reach areas
Solution Approach 1:
The coupling interface is segmented into discrete pin locations that align with apertures in the frame rails, allowing each pin to be independently installed and inspected. This segmentation simplifies the overall connection system while maintaining structural integrity through distributed load paths.
Solution Approach 2:
The complex bolt-based fastening system is extracted and replaced with a simpler pin-and-retainer system. The retainer component is specifically designed to be accessible from above the torque box, extracting the inspection difficulty from the system and placing it at a easily accessible location.
2Reliability
If multiple bolts are used to couple the torque box to the frame, then the connection reliability is improved, but the time required for inspection and maintenance increases
Solution Approach 1:
The retainer is designed to be easily accessible and operable by maintenance personnel without requiring specialized tools or extensive disassembly. The simple pin insertion and retainer engagement mechanism allows maintenance personnel to perform inspections and replacements quickly, essentially serving their own maintenance needs without requiring complex service procedures.
3Stability of the object's composition
If a complex coupling interface with multiple fasteners is used, then the structural stability is improved, but the device complexity increases
Solution Approach 1:
The pin-and-retainer system serves multiple functions: it provides structural connection, allows for easy inspection, enables quick maintenance, and ensures proper alignment through the aperture design. This universal system replaces multiple specialized components with a single versatile mechanism that accomplishes all necessary functions.
Data Source
AI summary
A fire apparatus includes a first frame rail, a second frame rail, a torque box, a first mounting assembly coupled to a first end of the torque box, a second mounting assembly coupled to an opposing second end of the torque box, a first plurality of pins, and a second plurality of pins. The first mounting assembly includes a first mount coupled to a first side of the torque box and a second mount coupled to an opposing second side of the torque box. The second mounting assembly includes a third mount coupled to the first side and a fourth mount coupled to the opposing second side. The first pins extend through the first frame rail and the first mount, and the second frame rail and the second mount. The second pins extend through the first frame rail and the third mount, and the second frame rail and the fourth mount.