Fuel Injector Needle Guide Electrical Connection
Solution Overview
Problem
Existing fuel injectors face challenges in accurately controlling the needle movement due to component wear and dispersion issues, which are exacerbated by connection reliability problems and productivity issues related to the assembly of resistive coatings and electrical connections required for diagnosis.
Innovation Solution
A fuel injector design featuring a first and second electrical connection extending from the needle guide to an external connector pin, allowing for the transmission of an electrical signal representing the needle's position, utilizing a metal strip and spring system for contact, and a method of assembly that includes positioning a metal ring on the actuator and connecting metal extensions for reliable electrical contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If resistive coatings and electrical connections are arranged in the injector for needle position diagnosis, then measurement precision of needle position is improved, but device complexity and assembly time increase
Solution Approach 1:
The patent combines the electrical connection function with the existing needle guide structure. The second electrical connection is integrated into the needle guide, eliminating the need for separate resistive coatings and complex electrical connection arrangements. This merging approach maintains measurement precision while reducing device complexity.
Solution Approach 2:
The needle guide serves multiple functions: it guides the needle mechanically and simultaneously provides electrical connection capabilities through the integrated second electrical connection. This multi-functionality eliminates the need for separate diagnostic electrical components, reducing assembly complexity while maintaining detection capability.
2Measurement precision
If resistive coatings and electrical connections are arranged in the injector for needle position diagnosis, then measurement precision of needle position is improved, but assembly time and productivity decrease
Solution Approach 1:
By merging the electrical connection function into the needle guide structure, the patent eliminates multiple separate assembly steps for resistive coatings and electrical connections. This integration significantly reduces assembly time and improves productivity while maintaining measurement precision.
Solution Approach 2:
The second electrical connection is pre-integrated into the needle guide during manufacturing, so that during final assembly, no additional electrical connection steps are required. This preliminary integration of electrical functionality accelerates the assembly process and improves productivity.
3Measurement precision
If electrical connections are established in the injector for needle position diagnosis, then measurement precision is improved, but connection reliability deteriorates due to wear and dispersion
Solution Approach 1:
The patent merges the electrical connection with the robust needle guide structure, utilizing the existing mechanical precision and stability of the needle guide to ensure reliable electrical contact. This integration eliminates the reliability issues associated with separate resistive coatings and electrical connections.
Solution Approach 2:
The needle guide, which is already a critical precision component in the injector, serves its own dual function of guiding the needle and providing electrical connection. This self-service approach eliminates the need for separate electrical connection components that would be subject to wear and dispersion, thereby improving reliability.
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 accurate detection of needle position and movement, improving control strategies by enhancing connection reliability and reducing assembly time, thus addressing the challenges of wear and dispersion in fuel injectors.
Implementation Method 1
The first electrical connection may be in contact with the metal lamella by a spring system arranged at the end of the first electrical connection
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A fuel injector (10) for an internal combustion engine comprises: an injector body (12) in which there are positioned an actuator (14), a control valve (21) and a needle guide (24). The actuator actuates the control valve (21), the control valve (21) controlling an injection needle (38) sliding in its guide (24) between an open position in which injection is permitted and a closed position in which the injection of fuel is prevented. The injector (10) additionally comprises a first electrical connection (42) extending from the guide (24) of the needle (38) to intermediate electrical connection means (40) internal to the injector, and also comprises a second electrical connection (44) extending from said intermediate connection means (40) to a connector pin (46) accessible from the outside of the injector so that an electrical signal indicative of the position of the needle can be transmitted from the guide (24) of the needle (38) to the connector pin (46) and therefore be accessible to an external electronic computer.