Crawler Driving Claw Projecting Contact Portion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional crawler propelling devices experience uneven contact pressure and deformation of the rubber belt due to the limited width of the driving claw, leading to potential interference with cored bar projections and increased noise, which affects durability and driving performance.

Innovation Solution

The introduction of a projecting contact portion on the driving claw, offset from the position opposed to the cored bar projection, disperses contact pressure across the belt width and reduces the likelihood of interference with cored bar projections, thereby minimizing deformation and noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the driving claw width is limited to avoid collision with cored bar projection, then reliability is improved, but contact pressure becomes uneven and deformation increases

Engineering Contradiction:
Improvecollision avoidanceVSAvoidcontact pressure uniformity
Core Design Contradiction:
ReliabilityVSStress or pressure

Solution Approach 1:

The contact surface is extended in the belt width direction (lateral dimension) rather than increasing the driving claw width in the rotational direction. This dimensional shift allows the contact pressure to be distributed across a wider area laterally, reducing the pressure concentration at the distal end while maintaining the original driving claw width that avoids collision with the cored bar projection.

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

Solution Approach 2:

The contact surface is designed with non-uniform width along the rotational direction, being wider at the proximal end and narrower at the distal end. This local variation in geometry compensates for the uneven pressure distribution, ensuring more uniform contact pressure across the entire contact surface while maintaining reliable engagement.

Inventive Principle:
Principle #3Local quality

2Stress or pressure

If the contacting area between driving claw and engaging recess is increased, then contact pressure is reduced, but the driving claw may interfere with cored bar projection

Engineering Contradiction:
Improvecontact pressureVSAvoidinterference avoidance
Core Design Contradiction:
Stress or pressureVSReliability

Solution Approach 1:

Instead of increasing the driving claw width in the rotational direction (which would cause interference), the contact surface is extended in the belt width direction. This dimensional change increases the contacting area and reduces contact pressure without compromising the clearance between the driving claw and cored bar projection.

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

3Stress or pressure

If the driving claw is made wider to distribute contact pressure, then contact pressure uniformity improves, but collision with cored bar projection becomes likely

Engineering Contradiction:
Improvecontact pressure distributionVSAvoidcollision risk
Core Design Contradiction:
Stress or pressureVSObject-affected harmful factors

Solution Approach 1:

The contact surface extension is directed along the belt width direction rather than increasing the radial width of the driving claw. This directional choice allows pressure distribution improvement without increasing the likelihood of collision with the cored bar projection, which is positioned in the rotational direction.

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

This arrangement reduces the risk of noise generation and maintains the initial performance of the crawler propelling device by evenly distributing the load across the contact surface, enhancing durability and driving performance.

Implementation Method 1

the contact surface of the engaging recess formed in the belt main body made of rubber as much as possible... the contact surface of the engaging recess contacting the distal end portion of the driving claw may be deformed to a greater extent

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP2554457B1Crawler travel device
Publication Date: 2016.03.16 BRIDGESTONE CORP
  • EP2554457B1 patent drawingFigure 1
  • EP2554457B1 patent drawingFigure 2
  • EP2554457B1 patent drawingFigure 3~5

AI summary

Engaging recesses (62) engageable with driving claws (31) are formed between cored bars (61) in a belt circumferential direction. A driving sprocket (3) has the driving claws (31) provided in an outer circumferential side of a disk-shaped member (30) overlapped with a moving trace of cored bar projections in lateral side view at predetermined intervals in the circumferential direction of the disk-shaped member (30). The driving claws (31) are projected laterally from a disk surface of the disk-shaped member (30) in a belt width direction intersecting the disk surface of the disk-shaped member (30). The engaging recesses (62) and the driving claws (31) have respective contact surfaces extending in opposition at a distance to each other, and a projecting contact portion (33) is provided on one of the contact surfaces at a position offset in the belt width direction from a position opposed to the cored bar projection (63). The projecting contact portion (33) projects in a direction to reduce a distance to the other of the contact surfaces, compared with the distance between the respective contact surfaces.