Reciprocating Trimmer Cam Layout for Vibration Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gardening trimmers experience couple imbalance due to the offset arrangement of eccentric cams, leading to unnecessary vibration and noise during operation.
Innovation Solution
The cam member is designed with an intermediate disk having eccentric cams offset in opposite directions, and blind holes or different density materials are used to balance the intermediate disk, canceling out the couple imbalance and reducing vibration and noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the first and second eccentric cams are offset in opposite directions from the rotation axis to enable reciprocating blade motion, then the blade reciprocation function is achieved, but couple imbalance is generated causing vibration and noise
Solution Approach 1:
The patent introduces a counterbalancing mechanism where additional weights or mass distribution is deliberately arranged on the cam member to counteract the couple imbalance generated by the offset eccentric cams. This counterweight arrangement creates an opposing moment that cancels out the harmful vibration and noise while preserving the blade reciprocation function.
Solution Approach 2:
The patent modifies the mass distribution parameters of the cam member by adjusting the position, mass, or configuration of balancing weights. By changing these parameters, the couple imbalance is compensated without affecting the operational reciprocation motion of the blades.
2Force
If the eccentric cams are positioned away from the rotation axis to provide sufficient cutting force, then cutting performance is improved, but couple imbalance increases causing more vibration
Solution Approach 1:
The patent positions balancing weights or adjusts mass distribution on the cam member to create counteracting moments that offset the couple imbalance generated by the eccentrically positioned cams. This allows the cams to maintain their optimal position for cutting force while the counterweights eliminate the harmful vibrations.
3Ease of manufacture
If the cam member structure is simplified to reduce manufacturing cost, then ease of manufacture is improved, but ability to balance couple imbalance is reduced
Solution Approach 1:
The patent integrates the balancing weights directly into the cam member structure, combining the functional cam components with the balancing mass in a single integrated part. This merging approach maintains couple imbalance compensation capability while simplifying the overall structure and reducing the number of separate components, thereby improving ease of manufacture.
Data Source
AI summary
A cam member includes an intermediate disk, a first eccentric cam disposed on an upper surface of the intermediate disk and connected to a first blade and a second eccentric cam disposed on a lower surface of the intermediate disk and connected to a second blade. A center of gravity of the first eccentric is positioned in a first direction from a rotation axis of the cam member. A center of gravity of the second eccentric cam is positioned in a second direction opposite to the first direction from the rotation axis. A center of gravity of an upper half of the intermediate disk is positioned in the second direction from the rotation axis. A center of gravity of lower half of the intermediate disk is positioned in the first direction from the rotation axis.