Spark Plug Insulator Compaction Speed Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The manufacturing of spark plugs faces challenges with insulator breakage due to stress caused by compacting powder materials, particularly when the size and diameter are reduced, leading to concerns about yield and productivity.

Innovation Solution

A method that controls the insertion speed of the terminal electrode during the second process, gradually reducing it to manage the compaction load on the insulator, ensuring the powder materials are compacted effectively without causing breakage, while maintaining productivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the terminal electrode is inserted at high speed to maintain productivity, then productivity is improved, but the insulator may break due to large compaction stress

Engineering Contradiction:
ImproveproductivityVSAvoidinsulator breakage risk
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The insertion speed of the terminal electrode is dynamically adjusted during the second process. The speed is reduced between the start and end of the process to control the compaction load on the insulator, preventing breakage while maintaining overall productivity through optimized process timing.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The insertion speed parameter is changed during the second process. By reducing the insertion speed between start and end, the compaction stress on the insulator is controlled, avoiding breakage while still achieving effective compaction of the powder materials.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the insertion speed is uniformly reduced to avoid insulator breakage, then reliability is improved, but productivity is degraded

Engineering Contradiction:
Improveinsulator breakage preventionVSAvoidproductivity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

Rather than uniformly reducing speed, the insertion speed is dynamically adjusted - reduced specifically between the start and end of the second process when compaction stress is highest, while maintaining higher speeds during other phases to preserve productivity.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The insertion process uses periodic variation in speed - faster insertion during initial and final stages, with reduced speed during the critical compaction phase between start and end, optimizing both reliability and productivity through timed speed modulation.

Inventive Principle:
Principle #19Periodic 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

This approach prevents insulator breakage and maintains high yield and productivity by optimizing the compaction process, especially when reducing spark plug size and diameter.

Implementation Method 1

the insulator after finishing the first process is heated to a temperature equal to or greater than the softening temperatures of the first to third powder materials

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

compact the first to third powder materials by the terminal electrode

Methodology Applied
Scientific EffectCompaction: Compression

Data Source

PatentEP2214276B1Method of manufacturing spark plug
Publication Date: 2019.09.04 NITERRA CO LTD
  • EP2214276B1 patent drawingFigure 1
  • EP2214276B1 patent drawingFigure 2
  • EP2214276B1 patent drawingFigure 3

AI summary

A decrease in yield and degradation of productivity can be avoided when a spark plug having an insulator with low mechanical strength is manufactured. In a second process, a terminal electrode 15 is inserted to a predetermined position in a state where an insulator 12 is heated to a temperature equal to or greater than the softening temperatures of first to third powder materials 16P, 17P, and 18P such that the first powder material 16P becomes a first conductive sealing material layer 16, the second powder material 17P becomes a resistor 17, and the third powder material 18P becomes a second conductive sealing material layer 18. In addition, a speed at which the terminal electrode 15 is inserted is reduced between the start and the end of the second process.