Centrifugal Clutch Weight Layout for Quick Coupling and Higher Capacity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing centrifugal clutches face issues with slow engagement due to long times to reach coupling state, leading to lowered fuel efficiency and small clutch capacity, and have complex configurations with increased manufacturing burdens due to multiple components.

Innovation Solution

A centrifugal clutch design featuring a drive plate, clutch outer, clutch weight with a protrusion, and a long hole-shaped pin slide hole allows for quick engagement by sliding the clutch weight backward to press against the clutch outer, reducing the number of components and manufacturing complexity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the clutch weight gradually comes into friction-contact with the clutch outer according to an increase in engine speed, then the clutch engagement is smooth, but a long time is necessary until the clutch is brought into a coupling state, leading to lowered fuel efficiency and small clutch capacity

Engineering Contradiction:
Improvesmooth engagementVSAvoidengagement time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The clutch weight is designed to dynamically shift position based on engine speed. At low speeds, the clutch shoe gradually contacts the clutch outer for smooth engagement. At high speeds, centrifugal force causes the clutch weight to shift outward, enabling the clutch shoe to quickly press against the clutch outer, achieving rapid coupling without sacrificing smoothness during the engagement process.

Inventive Principle:
Principle #15Dynamics

2Power

If two drive plates are provided to increase clutch capacity, then the clutch capacity is increased, but the configuration becomes complicated and manufacturing burden increases

Engineering Contradiction:
Improveclutch capacityVSAvoidnumber of components
Core Design Contradiction:
PowerVSDevice complexity

Solution Approach 1:

The single drive plate is segmented into multiple functional zones: a clutch weight portion that rotates with the drive plate, a clutch shoe portion that contacts the clutch outer, and a driven portion with a cam body that interacts with a protrusion on the drive plate. This segmentation allows one component to perform multiple functions that previously required two separate drive plates, thereby increasing clutch capacity while maintaining a simple configuration.

Inventive Principle:
Principle #1Segmentation

3Loss of time

If the clutch weight is designed to quickly press the clutch outer to increase clutch capacity, then engagement time is reduced, but the configuration becomes more complex

Engineering Contradiction:
Improveengagement timeVSAvoidconfiguration complexity
Core Design Contradiction:
Loss of timeVSDevice complexity

Solution Approach 1:

The invention merges the clutch weight, clutch shoe, and cam body into a single integrated component. The clutch weight has a clutch shoe formed to extend along the circumferential direction and face the clutch outer, with a driven portion that climbs on the protrusion. This merging allows the component to quickly press the clutch outer through the cam-protrusion interaction while maintaining a simple overall configuration that does not require additional separate parts.

Inventive Principle:
Principle #5Merging (Combining)

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

This design enhances clutch capacity with a simple configuration, reducing engagement time and manufacturing burdens while maintaining strong clutch shoe pressure on the clutch outer.

Implementation Method 1

a centrifugal clutch configured to transmit rotary drive force to a driven side when an engine reaches a predetermined rotation speed

Methodology Applied
Scientific EffectCentrifugal force: Centrifugal Force

Implementation Method 2

the clutch shoe friction-contacts the clutch weight

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3486518B1Centrifugal clutch
Publication Date: 2021.11.17 FCC KK
  • EP3486518B1 patent drawingFigure 1
  • EP3486518B1 patent drawingFigure 2
  • EP3486518B1 patent drawingFigure 3

AI summary

Provided is a centrifugal clutch having a simple configuration and configured so that a clutch capacity can be increased. A centrifugal clutch (200) includes a drive plate (210) to be directly rotatably driven by drive force of an engine. The drive plate (210) includes swing support pins (214) and protrusions (218). The swing support pin (214) is fitted in a pin slide hole (231) formed at a clutch weight (230), and swingably supports the clutch weight (230). The protrusion (218) includes a cylindrical roller, and contacts a driven portion (235) of the clutch weight (230). The pin slide hole (231) is formed in a long hole shape allowing the clutch weight (230) to displace backward in a rotary drive direction of the drive plate (210). The driven portion (235) is formed to extend inclined outward to a rear side in the rotary drive direction of the drive plate (210).