Retroreflector Cleaning Unit with Speed-Adaptive Spraying

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Manual cleaning of retroreflectors along roadways is costly, time-consuming, and poses safety risks, with high consumption of washing and rinsing fluids and the need for extensive human personnel, while also allowing grass and shrubs to obscure visibility.

Innovation Solution

A cleaning unit mounted on a vehicle with automated nozzles and sensors for sequential washing, rinsing, and herbicide application, minimizing fluid consumption and personnel use, allowing continuous operation and reduced vegetation growth.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If manual cleaning is performed by staff moving from one reflector to another, then the retroreflectors can be cleaned individually, but the process is expensive, time-consuming, and requires extensive human personnel

Engineering Contradiction:
Improvemanual cleaning operationVSAvoidcleaning efficiency
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The patent replaces manual mechanical cleaning operations with an automated vehicle-mounted system that uses mechanical movement of the vehicle along the roadway to position cleaning apparatus relative to retroreflectors. The system substitutes human labor with automated control systems, sensors, and mechanical actuators that perform cleaning operations without manual intervention at each reflector location.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The cleaning system performs self-positioning and self-execution of cleaning operations through automated control. The vehicle-mounted apparatus automatically detects retroreflector locations, positions cleaning components, and executes washing and rinsing sequences without requiring human operators to manually service each individual reflector, thereby dramatically improving productivity.

Inventive Principle:
Principle #25Self-service

2Ease of operation

If manual cleaning is performed without closing the road section, then the road remains accessible, but workers are exposed to serious dangers

Engineering Contradiction:
Improveroad accessibility during cleaningVSAvoidworker safety
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent replaces human workers with an automated vehicle-mounted cleaning system that operates independently on the roadway. This substitution eliminates exposure of human personnel to traffic dangers while maintaining road accessibility, as the automated system can operate without requiring road closure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Illumination intensity

If staff are instructed to cut and weed vegetation hiding retroreflectors, then visibility of retroreflectors is improved, but the process becomes even more expensive in terms of time and money

Engineering Contradiction:
Improveretroreflector visibilityVSAvoidoverall process efficiency
Core Design Contradiction:
Illumination intensityVSProductivity

Solution Approach 1:

The patent combines multiple functions into a single integrated vehicle-mounted system: retroreflector cleaning, vegetation management through herbicide application, and visibility verification. By merging these operations, the system achieves improved retroreflector visibility without requiring separate manual vegetation cutting operations, thereby maintaining productivity.

Inventive Principle:
Principle #5Merging (Combining)

4Manufacturing precision

If periodic cleaning is performed manually one-to-one, then each retroreflector receives individual attention, but the number of retroreflectors to be cleaned being high makes the process expensive and time-consuming

Engineering Contradiction:
Improveindividual reflector cleaning qualityVSAvoidtotal cleaning time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent implements continuous cleaning operation as the vehicle moves along the roadway, continuously treating retroreflectors in sequence without interruption. The system maintains continuous washing and rinsing actions on multiple reflectors simultaneously through the vehicle's movement, eliminating the stop-start nature of manual one-to-one cleaning and dramatically reducing total cleaning time while maintaining quality.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The system performs preliminary positioning and preparation operations as the vehicle approaches each retroreflector, pre-positioning cleaning components and activating appropriate cleaning sequences in advance. This preliminary action ensures that each reflector receives proper individual attention while maintaining overall process continuity and efficiency.

Inventive Principle:
Principle #10Preliminary action

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 efficient, cost-effective, and safe automatic cleaning of retroreflectors with reduced operational time and fluid usage, minimizing human intervention and vegetation growth, while maintaining visibility.

Implementation Method 1

spraying, with a first nozzle (5), of a washing fluid (L1) on the retroreflector (R)

Methodology Applied
Scientific EffectFluid spray cleaning: Fluid Spray

Implementation Method 2

spraying, with a second nozzle (12), of a rinsing fluid (L2) on the washed retroreflector (R)

Methodology Applied
Scientific EffectFluid spray rinsing: Fluid Spray

Implementation Method 3

spraying, with a third nozzle (31), of a herbicide fluid (L3) on the area (A) surrounding the retroreflector (R)

Methodology Applied
Scientific EffectHerbicide application:

Data Source

PatentEP2909377B1Cleaning unit for retroflectors
Publication Date: 2016.09.14 AIROXMIG
  • EP2909377B1 patent drawingFigure 1~2
  • EP2909377B1 patent drawingFigure 3~4
  • EP2909377B1 patent drawingFigure 5a~5c

AI summary

A cleaning unit for retroreflectors (R) comprising a vehicle (V) susceptible to continuously forward on a roadway (W) along a forwarding direction (d') substantially parallel to the boundary line (d) defined by the retroreflectors (R); a device (15) for the selective detection of the presence of a retroreflector (R) to be cleaned; a first spraying device (2) for spraying the washing fluid to the retroreflectors (R) to be cleaned; a second spray device (10) for spraying the rinsing fluid on the retroreflector washed (R); data processing means (20) operatively connected with the detection device (15) and with the first and the second spraying device (2, 10) for selectively activating the first spray device (2) at a first predetermined time interval (t1) from the detection of the retroreflector to be cleaned (R) and for selectively activating the second spraying device (10) at a second predetermined time interval (t2) from the activation of the first spray device (2). The data processing means (20) are susceptible to calculate the first and the second time interval (t1, t2) according to the forwarding speed (s) of the vehicle (V) so that the cleaning unit continuously acts on the retroreflectors (R) while advancing along the forwarding direction (d).