Spring-Loaded Hinge Lock Mechanism to Reduce Door Closing Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Spring-loaded hinge assemblies for appliance doors face an undesirable trade-off between maintaining sufficient biasing force to keep the door closed and minimizing closing resistance, particularly in the last portion of hinge movement prior to closure.
Innovation Solution
A spring-loaded hinge assembly with a lock that rotates to hold the coil spring in a partially compressed pre-load condition and pivot bush in a partially retracted position, reducing closing force by altering the cam and pivot bush interaction, thus minimizing resistance in the final degrees of closure while maintaining sufficient biasing force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a spring-loaded hinge assembly uses a coil spring to provide biasing force to hold the door closed, then the door remains securely closed during appliance operation, but closing resistance increases in the last portion of hinge movement prior to closure
Solution Approach 1:
The lock engages the cam and pivot bush in advance before the door reaches the closed position, pre-compressing the spring and positioning the pivot bush to reduce closing resistance. This preliminary action prepares the mechanism to minimize resistance during the final approach to closure while maintaining secure holding force.
Solution Approach 2:
The pivot bush is made movable relative to the cam, allowing it to dynamically adjust its position during door movement. The lock controls this movement, enabling the pivot bush to be in a retracted position during most of the closing motion (reducing resistance) and then engage with the cam near the end (maintaining holding force).
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 reduces closing resistance in the last portion of hinge movement while ensuring the appliance door remains closed during operation, improving upon traditional designs by limiting the closing force to only the last few degrees of closure.
Implementation Method 1
The coil spring applies a biasing force to the spring support member, which operates to push the pivot bush against the cam
Implementation Method 2
The leaf includes a cam and the pivot bush is positioned to contact the cam
Data Source
AI summary
A spring-loaded hinge assembly including a hinge support bracket and a leaf that is pivotally mounted to the hinge support bracket. A coil spring is supported on a spring support member, which includes a pivot bush. The coil spring applies a biasing force to the spring support member, which operates to push the pivot bush against a cam on the leaf. A lock configured to rotate between locked and unlocked positions includes a finger that engages an engagement feature on the hinge support bracket when the lock rotates to the locked position as the leaf swings toward the open position. In the locked position, the lock holds the coil spring in a partially compressed, pre-load condition and the pivot bush at a partially retracted position relative to the cam until the lock is subsequently released by contact between the cam and the pivot bush during subsequent closure.