Water Injection Device Back-Suction Icing Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Internal combustion engines face challenges in optimizing fuel consumption due to knock tendencies and high exhaust gas temperatures, which are exacerbated by the risk of icing or freezing in water injection devices when operated below freezing temperatures, potentially damaging components.

Innovation Solution

A method where the water injection device operates in suck-back mode to minimize the risk of icing by allowing air to flow through the water injector, reducing the water volume in the system and preventing negative pressure, thereby efficiently sucking back water and avoiding damage from freezing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If water is left in the water-carrying components when the vehicle is operated below freezing point, then the device can remain ready for immediate use, but the water may freeze and cause damage to components

Engineering Contradiction:
Improvedevice readinessVSAvoidfreezing damage
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The pump extracts water from the water-carrying components and returns it to the water tank, removing the harmful substance (water that could freeze) from vulnerable components while preserving device readiness

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If the pump operates in suck-back mode without opening the water injector, then water can be pumped back efficiently, but negative pressure may form and hinder the sucking back process

Engineering Contradiction:
Improvewater suction efficiencyVSAvoidnegative pressure
Core Design Contradiction:
ProductivityVSStress or pressure

Solution Approach 1:

Air acts as an intermediary substance that enters the second line through the open water injector, preventing the formation of strong negative pressure and enabling efficient water suction back to the tank

Inventive Principle:
Principle #24Intermediary (Mediator)

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 approach effectively minimizes the risk of icing and freezing in water-carrying components, ensuring the device's integrity and maintaining optimal engine performance without compromising exhaust gas treatment or fuel efficiency.

Implementation Method 1

a pump (4) for conveying the water, the pump (4) being connected to the water tank (3) via a first line (10), to a water injector (6) via a second line (11)

Methodology Applied
Scientific EffectPump: Pump

Implementation Method 2

the at least one water injector (6) is opened so that air flows into the second line (11). As a result, the water from the second line (11) and the at least one water injector (6) is sucked back into the water tank (3)

Methodology Applied
Scientific EffectPressure gradient: Pressure Gradient

Data Source

PatentEP3292288B1Method for operating a device for injecting water into an internal combustion engine
Publication Date: 2021.06.09 ROBERT BOSCH GMBH
  • EP3292288B1 patent drawingFigure 1~2
  • EP3292288B1 patent drawingFigure 3a~3b

AI summary

Method for operating a device (1) for injecting water into an internal combustion engine, wherein the device (1) has – a water tank (3) for storing water, – a pump (4) for delivering the water, wherein the pump (4) is connected to the water tank (3) via a first line, and wherein the pump (4) can be operated in a delivery mode and in a back-suction mode, – a drive (5) for driving the pump (4), – at least one water injector (6) which is designed for injecting water into an air-conducting line (7) of the internal combustion engine (2), wherein the water injector (6) is connected to the pump (4) via a second line (11), wherein, during the operation of the pump (4) in the back-suction mode, in which the water is delivered in the direction of the water tank (3), the at least one water injector (6) is opened such that air flows into the second line (11).