Cam Stroke Adjustment Mechanism for Work Implement Units

Solution Overview

Problem

Existing work vehicles, such as lawn mowers, face increased manufacturing and maintenance costs due to the use of hydraulic control systems for vertically moving work implement units, which also burden operators with complex operations.

Innovation Solution

A stroke adjustment mechanism using a cam member and cam engaging unit on a rod, allowing for manual operation to lock and unlock the work implement unit at predetermined positions, eliminating the need for hydraulic or electric systems by utilizing a cam mechanism for relative rotation and retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If hydraulic control systems are used for vertically moving work implement units, then the work implement unit can be moved smoothly and precisely, but manufacturing cost and maintenance cost increase

Engineering Contradiction:

Improvesmooth and precise movementVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent replaces the hydraulic control system with a purely mechanical stroke adjustment mechanism. The cam member with cam surfaces interacts with the rod to produce relative rotation and achieve stroke adjustment through mechanical means alone, eliminating hydraulic components and reducing manufacturing and maintenance costs while maintaining functional reliability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent extracts and removes the hydraulic control system from the work vehicle, retaining only the essential mechanical components needed for stroke adjustment. By taking out the complex hydraulic system and replacing it with a simplified mechanical cam mechanism, the invention reduces cost while preserving the core functionality of vertical movement control

Inventive Principle:

Principle #2Taking out (Extraction)

2Reliability

If hydraulic control systems are used for vertically moving work implement units, then the work implement unit can be moved smoothly and precisely, but maintenance cost increases

Engineering Contradiction:

Improvesmooth and precise movementVSAvoidmaintenance cost

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The patent replaces the hydraulic control system with a purely mechanical stroke adjustment mechanism. The cam member with cam surfaces interacts with the rod to produce relative rotation and achieve stroke adjustment through mechanical means alone, eliminating hydraulic components and reducing manufacturing and maintenance costs while maintaining functional reliability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The mechanical cam mechanism is inherently more reliable and easier to maintain than hydraulic systems. The simple mechanical components can be easily inspected, adjusted, and repaired by operators themselves without requiring specialized hydraulic system knowledge or expensive professional maintenance services

Inventive Principle:

Principle #25Self-service

3Ease of operation

If hydraulic control systems are used for vertically moving work implement units, then operational control is achieved, but operator burden increases due to complex operations

Engineering Contradiction:

Improveoperational controlVSAvoidoperational complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The patent replaces the hydraulic control system with a purely mechanical stroke adjustment mechanism. The cam member with cam surfaces interacts with the rod to produce relative rotation and achieve stroke adjustment through mechanical means alone, eliminating hydraulic components and reducing manufacturing and maintenance costs while maintaining functional reliability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The stroke adjustment mechanism is segmented into distinct functional components: the rod with cam engaging unit, the cam member with specific cam surfaces, and the locking mechanism. This segmentation allows each component to perform its specific function independently, simplifying the overall operation and making the system easier to understand and control

Inventive Principle:

Principle #1Segmentation

4Device complexity

If a cam mechanism is used for stroke adjustment, then device complexity is reduced, but manufacturing precision requirements increase

Engineering Contradiction:

Improvesystem simplicityVSAvoidcam surface precision

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent employs specific cam surface parameters including inclination angles of 45 degrees and arc-shaped profiles with predetermined radii. By carefully selecting and standardizing these geometric parameters, the invention achieves the desired functional performance while maintaining manufacturability through conventional machining processes

Inventive Principle:

Principle #35Parameter changes

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 solution simplifies operator burden by enabling easy manual operation to lock and unlock the work implement unit, reducing overall costs and operational complexity while maintaining precise control.

Implementation Method 1

a cam member for producing relative rotation with the cam engaging unit through contact with the cam engaging unit in a cam movement rotational phase region

Methodology Applied

Scientific EffectCam mechanism: Cam

Implementation Method 2

an inclined cam portion formed in the cam member, having a function to retain the work implement unit in a retaining position

Methodology Applied

Scientific EffectMechanical force: Mechanical Force

Data Source

PatentUS8756903B2Work vehicle with stroke adjustment mechanism for suspended work implement unit

Publication Date: 2014.06.24 KUBOTA CORP

AI summary

A work vehicle including a control device for moving an implement through a mechanism including an adjustment mechanism for locking the work implement unit with a predetermined stroke position including a rod, a cam engaging unit mounted on the rod and a cam for producing rotation with the cam engaging unit. The cam retains the work implement in a retaining position through first operational movement of the control device for moving the work implement unit from a basic position to a far side position beyond the retaining position and then returning the work implement unit to the retaining position, and allows the work implement unit to return to the basic position through a second movement control device.