Furnace Door Latch Plate Assembly for Low-Force Knob Rotation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Furnace door latches require excessive turning or pinch force to rotate the knob and unlock the door, making them difficult to operate ergonomically.
Innovation Solution
A latch assembly with a latch plate that supports the door's weight and reduces the pinch force needed, featuring a threaded screw to securely couple the knob to the latch, and a design allowing 90-degree rotation for easy latching and unlatching with minimal effort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a two piece door knob and latch is used to secure the furnace door, then the door can be secured to the furnace cabinet, but a greater amount of turning or pinch force is required to rotate the knob and unlock the door
Solution Approach 1:
The latch assembly is divided into separate functional components: a latch body with engagement features, a rotatable knob, and a threaded rod. This segmentation allows each component to be optimized independently - the latch body provides secure engagement while the knob provides ergonomic rotation with reduced force requirements.
Solution Approach 2:
The invention transitions from a simple rotational locking mechanism to a multi-dimensional system incorporating linear threading motion. The threaded rod converts rotational motion of the knob into linear motion that actuates the latch, providing mechanical advantage and reducing the force needed at the knob while maintaining secure door engagement.
2Reliability
If a traditional door latch mechanism is used, then the door can be locked, but excessive pinch force is required to operate the latch
Solution Approach 1:
The threaded rod acts as an intermediary mechanism between the user's input force on the knob and the latch engagement force. It provides mechanical advantage by converting small rotational forces into larger linear forces that actuate the latch, thereby reducing the pinch force required at the knob while maintaining reliable engagement.
Solution Approach 2:
The invention changes the force application parameters by introducing a threaded mechanism with specific pitch and lead. This transforms the force-displacement relationship, allowing the same latch engagement force to be achieved with significantly reduced input force at the knob through the mechanical advantage of the thread geometry.
Data Source
AI summary
A latch assembly for securing a furnace door to a furnace casing includes a latch for placement on an inside of the furnace door; a knob for placement on a front surface of the furnace door; a latch plate for placement between the latch and the knob; and a threaded screw for threadably coupling the knob to the latch. The latch plate supports the weight of the furnace door in a closed position and reduces a pinch force used for rotating the knob.