Stator Bar Ends for Printed Circuit Board Interconnection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for connecting electrically conductive bars in electrical machines to printed circuit boards are complex and costly, especially when dealing with rectangular cross-sectional bars, as they require additional production steps like milling and the use of separate components for mechanical force absorption.
Innovation Solution
The solution involves reducing the cross-sectional area of the bar ends to fit through standard circular holes in the printed circuit board, allowing for a non-positive connection without additional components, and optionally using forked or curved ends for enhanced conductivity and mechanical fit.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rectangular cross-sectional bars are connected to printed circuit board through through-openings, then electrical connection is achieved, but the through-opening requires complex milling which increases production steps and costs
Solution Approach 1:
The bar is segmented into two distinct parts: a first cross-sectional area in the region of the slots with rectangular shape for electrical connection, and a second reduced cross-sectional area at the end for mechanical insertion through circular through-openings. This segmentation allows the bar to fulfill both electrical and mechanical requirements without requiring complex milling of the printed circuit board.
Solution Approach 2:
Different parts of the bar have different cross-sectional areas optimized for their specific functions: the first cross-sectional area maintains rectangular shape for electrical conductivity and connection, while the second cross-sectional area is reduced to enable easy insertion through standard circular holes. This local differentiation eliminates the need for complex milling operations.
2Strength
If additional contact elements are used to connect winding to inverter circuit, then mechanical forces are absorbed, but the connection becomes complex requiring welding or soldering
Solution Approach 1:
The bar combines both electrical conduction and mechanical force absorption functions into a single integrated component. The reduced second cross-sectional area at the end of the bar provides mechanical strength for force absorption while maintaining electrical continuity, eliminating the need for separate contact elements and complex welding or soldering operations.
Solution Approach 2:
The bar serves multiple functions simultaneously: it conducts electricity from the winding to the inverter circuit, absorbs mechanical forces through its reduced cross-sectional area, and provides structural support. This multi-functionality simplifies the overall connection structure by eliminating the need for separate specialized components.
3Reliability
If metal eyelets are introduced for electrical connection, then connection is achieved, but additional production steps and costs are incurred
Solution Approach 1:
The invention extracts the unnecessary intermediate component (metal eyelet) from the connection process. The bar itself is designed with the appropriate geometry to directly connect to the printed circuit board through standard circular through-openings, eliminating the need for additional metal eyelets and their associated production steps.
4Strength
If through-opening diameter is adapted to rectangular busbar cross section, then frictional connection is achieved, but the opening requires complex shape and separate production step
Solution Approach 1:
Instead of adapting the through-opening shape to match the rectangular busbar cross-section (which would require complex milling), the invention inverts the approach: the bar's second cross-sectional area is adapted to match the simple circular shape of the through-opening. This reversal simplifies the manufacturing of the printed circuit board while maintaining a secure frictional connection.
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 simplifies the manufacturing process, eliminates the need for complex cutouts, and provides a reliable electrical connection without additional components, reducing production time and costs while ensuring a secure mechanical fit.
Implementation Method 1
Depending on the diameter of the through-hole, this results in a frictional connection that holds the printed circuit board to the busbar
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an electrical machine (1) having a stator (2) with an electrical winding which has electrically conductive bars (5) which are arranged in slots (4) in the stator (2), and each of which has, in the region of the slots (4), a first cross-sectional area (21), and an inverter circuit (9) for supplying current to the winding in a controlled manner, wherein the inverter circuit (9) is electrically connected to the winding and/or the bars are electrically connected to one another by means of at least one printed circuit board arrangement (8). The invention provides that the at least one printed circuit board arrangement (8) has passage bores (11) with a diameter smaller than a maximum dimension (12) of the first cross-sectional area (21), and in each case one bar end (10) of one of the bars (5) is passed through each passage bore (11), wherein the bar end (10) which is passed through said passage bore has, in the region of the passage bore (11), a second cross-sectional area (22) with a maximum dimension (13) which is smaller than the diameter of the passage bore (11) or equal to the diameter of the passage bore (11).