Bus Bar Spacer Design Preventing Vibration Detachment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for attaching bus bars to chassis in electronic devices, such as DC-DC converter units in hybrid vehicles, face issues with resin spacers falling off due to vibration during screw fastening, leading to increased man-hours for reattachment and potential wastage of time during manufacturing and use.
Innovation Solution
A bus bar design featuring integrated resin spacers with a head portion covering the peripheral edge of the through hole and a body portion with a larger lower end cross-sectional area, preventing upward movement and securely adhering to the bus bar body, combined with a heat-transfer sheet for efficient heat release.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If resin spacers are attached to bus bar before screw fastening, then insulation between bus bar and chassis is secured, but resin spacers may fall off due to vibration during screw fastening requiring reattachment
Solution Approach 1:
The resin spacer is pre-formed with a head portion that covers the peripheral edge of the through hole and a body portion with a larger lower end cross-sectional area than upper end cross-sectional area. This preliminary structural design ensures that when the spacer is inserted into the through hole, the head portion prevents upward movement and the body portion provides frictional resistance, eliminating the need for reattachment during screw fastening operations.
Solution Approach 2:
The resin spacer is made of resin material that provides both electrical insulation properties and mechanical bonding properties. The composite structure combines the insulating function with the retaining function through the integrated head and body portions, achieving both insulation security and prevention of spacer detachment.
2Reliability
If multiple resin spacers are attached at multiple positions, then complete insulation is achieved, but increased complexity in assembly process occurs
Solution Approach 1:
Multiple resin spacers are pre-formed with the head-body structure before assembly. This preliminary preparation ensures that during the assembly process, workers simply need to insert the spacers into the through holes without complex operations, maintaining insulation completeness while minimizing assembly complexity.
3Reliability
If separate spacer fitting is performed, then insulation is secured, but additional manufacturing steps and time are required
Solution Approach 1:
The resin spacers are pre-formed with the optimized head-body structure before the bus bar assembly process. This preliminary preparation eliminates the need for separate spacer fitting steps during manufacturing, as the spacers are designed to be directly inserted and retained in the through holes, thereby reducing manufacturing cycle time while ensuring insulation security.
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 effectively prevents resin spacers from falling off, reducing wasteful processes and rework, enhancing manufacturing efficiency and ensuring reliable attachment without the need for separate spacer fitting or additional molds.
Implementation Method 1
An outer peripheral surface of the body portion is fixedly adhered to the inner peripheral surface of the first through hole portion so that resistance occurs when the spacer moves toward the head portion side relative to the bus bar body.
Implementation Method 2
A heat-transfer sheet for releasing heat of the bus bar body to the chassis is interposed between the surface of the bus bar, the surface being in the same plane as the extremity of the body portion and a position where the bus bar is fixed.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A bus bar includes a bus bar body and a spacer provided on the bus bar body, the spacer being an insulator. The bus bar body includes a through hole portion forming a through hole that allows a part of a fixing member for fixing the bus bar body to be inserted therethrough. The spacer includes a head portion and a body portion extending from the head portion. When the spacer is provided on the bus bar body, the head portion covers at least a part of a peripheral edge region of an end opening of the through hole and the body portion covers an inner peripheral surface of the through hole portion. An extremity of the body portion and a surface of the bus bar body are substantially in a same plane. An outer peripheral surface of the body portion of the spacer is fixedly adhered to the inner peripheral surface of the through hole portion so that resistance occurs when the spacer moves toward the head portion side relative to the bus bar body.