Slidable Coil Former for Current Transducer Core Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing current transducers face challenges in cost-effective manufacturing and maintaining high performance due to the need for costly and complex winding processes, which can lead to plastic deformation of the magnetic core, affecting the transducer's performance, especially for coils with many turns or small transducers.
Innovation Solution
A current transducer design featuring a housing with a coil support that includes a radially inner and outer support portion with spacer elements, allowing for slidable displacement and maintaining a core receiving channel, enabling easy assembly and winding of coils without plastic deformation of the magnetic core, thus ensuring reliable performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the coil is wound around the magnetic core by passing the wire through the air gap, then the coil can be assembled, but the process requires special tooling and is costly and complex
Solution Approach 1:
A coil support structure is introduced as an intermediary component between the magnetic core and the coil. The coil support includes a core receiving channel that guides the magnetic core and provides a stable foundation for coil winding. This intermediary structure eliminates the need for complex tooling to pass wire through the air gap, as the coil can now be wound around the support structure in a straightforward manner.
2Ease of manufacture
If the magnetic core is bent to allow coil insertion, then the coil can be mounted easily, but plastic deformation modifies the soft magnetic properties of the magnetic core
Solution Approach 1:
The coil support structure is prepared in advance with a core receiving channel that is specifically designed to receive and properly position the magnetic core without requiring any deformation of the core itself. The support structure is configured beforehand to accommodate the magnetic core in its natural, undeformed state, thereby preserving the magnetic core's soft magnetic properties while still enabling easy coil mounting.
3Reliability
If the coil extends over a long section of the magnetic core with large number of turns, then the transducer performance is improved, but the winding process becomes even more difficult and costly
Solution Approach 1:
The coil support structure serves as a mediator that facilitates the winding of coils with large numbers of turns over long sections of the magnetic core. The support structure provides a stable, extended framework that guides the wire during winding, making it easier to create numerous turns without requiring complex tooling or procedures. This intermediary structure transforms a difficult winding operation into a more manageable process.
4Volume of moving object
If small current transducers are made, then the device size is reduced, but winding the coil becomes difficult or impossible using traditional techniques
Solution Approach 1:
The coil support structure is designed as a separate, modular component that can be independently manufactured and then assembled with the magnetic core and coil. This segmentation allows the support structure to be precisely sized and shaped for small transducer applications, providing the necessary framework for coil winding in compact geometries where traditional winding techniques would be impossible.
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 design facilitates cost-effective and efficient assembly of current transducers with high performance and reliable measurement ranges, particularly for coils with a large number of turns, by avoiding plastic deformation of the magnetic core and maintaining the core's magnetic properties.
Implementation Method 1
The magnetic flux generated by the electrical current flowing in the primary conductor is concentrated by the magnetic core and is representative of the primary current
Implementation Method 2
the magnetic field sensor is connected in a feed-back loop to a compensation coil, also generally called a secondary coil, which is typically wound around a portion of the magnetic core in order to generate a compensation current that tends to cancel the magnetic field generated by the primary conductor
Implementation Method 3
Secondary coils are also employed in current transducers of the open-loop type, but as pick-up coils that measure the magnetic field concentrated in the magnetic core in a transformer effect
Data Source
Figure 1a~2
Figure 3~4b
Figure 5a~5c
AI summary
Current transducer including a housing (2) comprising a coil support (4), a magnetic core (5) extending between a first end (20a) and a second end (20b), and a coil (6) comprising a plurality of windings formed around the coil support (4). The coil support (4) comprises a core receiving channel (13) within which the magnetic core is inserted, the coil support comprising a radially inner support portion (10) and a radially outer support portion (12) between which the core receiving channel (13) is disposed. The radially inner support portion (10) is slidably movable with respect to the radially outer support portion (12).