Radial-Acting Clutch for Automatic Transmission Switching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing walk-behind work machines require manual intervention for switching between transmission states of the transmission apparatus, which is complex and inefficient, especially when transitioning between prime mover-driven and operator-driven modes.

Innovation Solution

A clutch mechanism with automatic switching capabilities, utilizing radial protrusions and biasing members to transition between engaged and disengaged states based on the prime mover's operating state, allowing for compact design and differential speed functionality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If manual control apparatus (control rod and pull wire) is used to switch transmission states, then the transmission coupling can be established or broken, but the operation becomes complex and requires manual intervention

Engineering Contradiction:
Improvemanual operation complexityVSAvoidautomatic switching capability
Core Design Contradiction:
Ease of operationVSExtent of automation

Solution Approach 1:

The clutch mechanism automatically switches between engaged and disengaged states based on the rotational state of the input member, without requiring manual intervention. The transmission member self-actuates through the protrusion mechanism when the input member rotates,实现ing self-service operation

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The clutch mechanism detects the rotational state of the input member through the protrusion and transmission member interaction, and automatically adjusts the transmission coupling state accordingly. This feedback mechanism enables automatic switching between transmission states based on operational conditions

Inventive Principle:
Principle #23Feedback

2Volume of moving object

If the transmission apparatus is designed to be compact, then the overall size is reduced, but the mechanism for automatic switching and differential function becomes more challenging to implement

Engineering Contradiction:
Improvetransmission apparatus sizeVSAvoidswitching mechanism complexity
Core Design Contradiction:
Volume of moving objectVSDevice complexity

Solution Approach 1:

The transmission member is disposed within the input member, with the protrusion extending radially from the input member into the transmission member. This nested arrangement allows the switching mechanism to be compact while maintaining the automatic switching and differential functions

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The transmission member moves in a direction that is not purely radial, incorporating both radial and axial components of motion. This multi-dimensional movement enables the compact design to achieve both automatic switching and differential speed functionality within a reduced volume

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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

Enables seamless automatic switching between transmission states without manual intervention, reducing resistance and enhancing operational efficiency and compactness, while facilitating speed differentials for smooth maneuverability.

Implementation Method 1

the biasing member is a spring, the spring having one end coupled to the at least one transmission member, and another end coupled to the input member or a mounting member for mounting the at least one transmission member

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP4209690B1Clutch and work machine having same
Publication Date: 2026.02.25 TECHTRONIC CORDLESS GP
  • EP4209690B1 patent drawingFigure 1
  • EP4209690B1 patent drawingFigure 2
  • EP4209690B1 patent drawingFigure 3~4

AI summary

The present invention provides a clutch (30) and a work machine (1) having same. The clutch comprises an input member (31) for receiving a driving force and rotating, an output member (32) for outputting rotational motion, and at least one transmission member (33). The input member has at least one radially extending protrusion. The output member has at least one transmission engagement part. The transmission member (33) is movable between a first position of engagement with the transmission engagement part (322) and a second position of disengagement, being located in a path of rotation of the protrusion (312), and able to abut the protrusion and be driven to move to the first position. Displacement of the transmission member between the first position and second position has a radial component. According to the technical solution of the present invention, the function of automatically switching between transmission states according to the operating state of a prime mover can be achieved. The fact that displacement of the transmission member comprises a radial component helps to reduce the axial thickness of the clutch, so that the structure thereof is more compact.