Fuel Injection Venturi Throttle Filter Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Fuel injection systems in internal combustion engines face susceptibility to faults due to clogging of venturi throttles in the zero delivery line, leading to malfunctions and pressure fluctuations, especially during zero delivery states.

Innovation Solution

Incorporating a filter at the inlet and constriction section of the venturi throttle, along with a gear pump design and an overflow valve system to manage fuel flow and reduce pressure fluctuations, and using a fine-mesh or laser-made filter to prevent particle entry and clogging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a venturi throttle is used in the zero delivery line to create vacuum and reduce opening pressure of suction valves, then the opening pressure of suction valves is reduced and fuel delivery quantity is increased, but particles can get stuck in the constriction area and cause clogging and system malfunction

Engineering Contradiction:
Improvefuel delivery quantityVSAvoidsystem susceptibility to clogging
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

A filter is introduced as an intermediary component in the zero delivery line between the venturi throttle constriction and the return line. This filter captures particles before they can lodge in the narrow constriction area, preventing clogging while maintaining the vacuum generation function of the venturi throttle that enables reduced suction valve opening pressure and increased fuel delivery.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The filter is positioned upstream of the constriction area to perform preliminary particle removal before the fuel flow reaches the vulnerable narrow passage. This preliminary action prevents particles from entering the constriction zone where they could cause blockages, thereby maintaining system reliability without compromising the venturi effect.

Inventive Principle:
Principle #10Preliminary action

2Stress or pressure

If the zero delivery line opens into the return line at the venturi throttle constriction to create vacuum, then pressure in the zero delivery line is reduced and suction valve opening pressure is lowered, but the system becomes susceptible to faults due to particle accumulation

Engineering Contradiction:
Improvepressure in zero delivery lineVSAvoidsystem fault susceptibility
Core Design Contradiction:
Stress or pressureVSReliability

Solution Approach 1:

The filter serves as a protective intermediary that maintains the low pressure environment created by the venturi throttle while simultaneously preventing particles from accumulating in the constriction area. This allows the system to benefit from reduced pressure without suffering from the reliability issues caused by particle accumulation.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Device complexity

If no filter is installed in the zero delivery line, then the system structure remains simple, but particles can enter the venturi throttle constriction and cause clogging and malfunctions

Engineering Contradiction:
Improvesystem structure simplicityVSAvoidsystem susceptibility to clogging
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The filter is designed as a compact intermediary component that integrates seamlessly into the existing zero delivery line structure. It provides essential particle filtration protection without significantly increasing overall system complexity, as it is a straightforward addition to the fluid pathway rather than a complex mechanical assembly.

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

Significantly reduces the risk of system failure by preventing particle-induced clogging and minimizing pressure fluctuations, ensuring reliable operation during zero delivery states and reducing fuel losses.

Implementation Method 1

the zero delivery line opens into the return in the area of a constriction of this venturi throttle. This ensures that in the case of zero delivery and the fuel flowing through the overflow valve and the return line, a vacuum is created within the venturi throttle in the area of the constriction, through which the leakage quantity is sucked from the zero delivery line into the return line.

Methodology Applied
Scientific EffectVenturi effect: Venturi Effect

Data Source

PatentEP2638276B1Fuel injection system of an internal combustion engine
Publication Date: 2016.08.17 ROBERT BOSCH GMBH
  • EP2638276B1 patent drawingFigure 1
  • EP2638276B1 patent drawingFigure 2

AI summary

The invention relates to a fuel injection system of an internal combustion engine, comprising a high pressure fuel pump (3), wherein a metering device (7) is connected upstream of the high pressure region (5) of said high pressure fuel pump and said metering device (7) feeds a fuel quantity conveyed from a supply tank (2) in metered quantities to the high-pressure region (5) via a feed line (8). A zero delivery line (18) branches from the feed line (8) and in the region of a constriction (20) of a Venturi throttle (19) opens into a return line (14), wherein furthermore the Venturi throttle (19) comprises a respective filter (22, 23) in an intake (21) and/or in a junction portion leading into the constriction (20).