Fuel Injection Valve Anchor Spring System

Solution Overview

Problem

The existing fuel injection valve in internal combustion engines experiences secondary injection due to upward displacement of the valve member, leading to inaccurate fuel injection amounts, as the biasing force of the spring affects the movable core's position and collision with the valve protrusion, resulting in variance in fuel injection timing and quantity.

Innovation Solution

A fuel injection valve design that attenuates the kinetic energy of the anchor using a spring biased in the valve closing direction, preventing upward displacement of the plunger rod by reducing the impact force when the anchor collides with the plunger rod, thus maintaining accurate fuel injection without secondary injection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the biasing force of the spring that biases the anchor in the valve opening direction is increased, then the movable core returns to the stable position faster, but the valve member is displaced upward when the movable core collides with the valve protrusion

Engineering Contradiction:

Improvereturn speed of movable coreVSAvoidfuel injection accuracy

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The spring system is segmented into two separate springs: a first spring that biases the anchor in the valve opening direction and a second spring that biases the anchor in the valve closing direction. This segmentation allows independent optimization of each spring's biasing force, enabling the first spring to provide strong return force while the second spring prevents upward displacement of the valve member during collision

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second spring acts as an intermediary element between the anchor and the valve member, providing a counteracting force that prevents the valve member from being displaced upward during anchor collision. This intermediary spring mediates the interaction between the moving components, allowing controlled energy dissipation

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the biasing force of the spring that biases the anchor in the valve opening direction is decreased, then upward displacement of the valve member is prevented, but the time required for the movable core to return to the stable position increases

Engineering Contradiction:

Improvefuel injection accuracyVSAvoidreturn time of movable core

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The spring system is segmented into two separate springs: a first spring that biases the anchor in the valve opening direction and a second spring that biases the anchor in the valve closing direction. This segmentation allows independent optimization of each spring's biasing force, enabling the first spring to provide strong return force while the second spring prevents upward displacement of the valve member during collision

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second spring is pre-configured to provide cushioning force before the anchor collides with the valve member. By positioning the second spring to engage and provide counteracting force in advance, the system prevents upward displacement of the valve member during the collision event, dissipating kinetic energy before it can cause harmful effects

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

3Device complexity

If a single spring is used to bias the anchor in the valve opening direction, then the structure is simple, but the fuel injection interval cannot be shortened without causing secondary injection

Engineering Contradiction:

Improvespring system structureVSAvoidfuel injection frequency

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The spring system is segmented into two separate springs: a first spring that biases the anchor in the valve opening direction and a second spring that biases the anchor in the valve closing direction. This segmentation allows independent optimization of each spring's biasing force, enabling the first spring to provide strong return force while the second spring prevents upward displacement of the valve member during collision

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The second spring is pre-configured to provide cushioning force before the anchor collides with the valve member. By positioning the second spring to engage and provide counteracting force in advance, the system prevents upward displacement of the valve member during the collision event, dissipating kinetic energy before it can cause harmful effects

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

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

The design shortens the fuel injection interval and prevents secondary injection, ensuring precise fuel delivery by regulating the anchor's displacement and reducing the impact force, thereby improving the reliability and efficiency of fuel injection.

Implementation Method 1

a coil which generates a magnetic attraction force through energization during a valve opening operation to open an injection hole while removes the magnetic attraction force by stopping the energization during a valve closing operation to close the injection hole

Methodology Applied

Scientific EffectMagnetic attraction force: Electromagnet

Implementation Method 2

the movable core is pushed back upward (in a valve opening direction) by a spring that biases the movable core in the valve opening direction from the opposite side of the fixed core

Methodology Applied

Scientific EffectSpring biasing force: Spring

Implementation Method 3

a fuel injection valve which attenuates kinetic energy of an anchor, which is displaced in a valve opening direction by a spring that biases the anchor in the valve opening direction from the opposite side of a fixed core, using a spring that biases the anchor in a valve closing direction from the fixed core side during a valve closing operation

Methodology Applied

Scientific EffectKinetic energy attenuation: Damping

Data Source

PatentUS10030621B2Fuel injection valve

Publication Date: 2018.07.24 ASTEMO LTD

AI summary

A fuel injection valve includes: a valve member; an anchor configured to be relatively displaceable in a valve opening-and-closing direction with respect to the valve member; a fixed core; a first spring biasing the valve member in a valve closing direction; a second spring biasing the anchor in the valve opening direction from an opposite side of the fixed core; and a third spring biasing the anchor in the valve closing direction from the fixed core side and has a biasing force smaller than a biasing force of the first spring and larger than a biasing force of the second spring where engagement portions are provided in both the anchor and the valve member to be engaged with each other when the anchor is displaced in the valve opening direction with respect to the valve member, thereby regulating the displacement of the anchor in the valve opening direction.