Vehicle Power Relay Three-Point Contact Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional power relays for commercial vehicles face issues with reliable contacting due to operational vibrations, which increase transition resistance between the movable contact bridge and terminal bolts, and increasing contact pressure requires a stronger magnet system, which is undesirable.

Innovation Solution

A power relay design featuring a housing with a force transmission element coupling a magnet armature to a contact bridge, which forms three-point contacts with mating contact elements, including a punctiform and convexly arched contact point, and a concave arched contact area, providing stable contact even under vibrations without the need for a stronger magnet system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If contact pressure is increased to counter vibrations, then contacting reliability is improved, but magnet system strength must be increased, which increases device complexity and size

Engineering Contradiction:
Improvecontacting reliabilityVSAvoidmagnet system strength
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The contact element features a convexly arched contact area with a defined support point, while the counter-contact element has a concave arched contact area. This curved surface geometry ensures that vibrations cause the contact elements to remain engaged at their support points without requiring increased contact pressure or magnet system strength, thereby resolving the contradiction between reliability and device complexity.

Inventive Principle:
Principle #14Spheroidality (Curvature)

2Ease of manufacture

If conventional flat contact surfaces are used, then manufacturing is simplified, but vibrations cause increased transition resistance and unreliable contacting

Engineering Contradiction:
Improvecontact surface manufacturingVSAvoidcontacting reliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

Instead of flat contact surfaces, the invention employs convex and concave arched contact areas that form a three-point support contact. This curved geometry actively compensates for vibrations by maintaining stable contact at the support points, thereby improving reliability while remaining manufacturable through standard forming processes.

Inventive Principle:
Principle #14Spheroidality (Curvature)

3Quantity of substance

If solid connection bolts with large diameter are used, then current carrying capacity is improved, but transition resistance increases under vibrations

Engineering Contradiction:
Improvecurrent carrying capacityVSAvoidtransition resistance stability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The convex and concave arched contact areas create a three-point support contact system that stabilizes the electrical connection between connection bolts and contact elements. This curved geometry prevents vibration-induced separation and maintains low transition resistance, allowing the use of appropriately sized connection bolts without compromising reliability.

Inventive Principle:
Principle #14Spheroidality (Curvature)

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 ensures reliable and stable electrical connections despite vibrations, maintaining contact integrity without the need for increased magnetic force, thus enhancing the operational reliability of the power relay.

Implementation Method 1

a magnetic coil and a magnet armature, which is coupled to a contact bridge via a force transmission element and can be displaced in the housing under the effect of a magnetic field generated by the magnet coil

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Data Source

PatentEP3086351B1Power relay for a vehicle
Publication Date: 2017.08.30 ELLENBERGER & POENSGEN GMBH
  • EP3086351B1 patent drawingFigure 1
  • EP3086351B1 patent drawingFigure 2
  • EP3086351B1 patent drawingFigure 3~4

AI summary

The invention relates to a power relay (1) for a vehicle, comprising a housing (2) into which two connecting bolts (10) are inserted for contacting a load circuit, and a coil assembly (16) arranged in the housing (2), which includes a magnetic coil (21) and a magnetic armature (19) which is coupled via a force transmission element (23) to a contact bridge (17) which is reversibly movable between a closed position and an open position and is displaceable in the housing (2) under the influence of a magnetic field generated by means of the magnetic coil (21), wherein the contact bridge (17) carries two contact elements (34) which, with mating contacts (33) of the connecting bolts (10), form a first contact pair (33, 34) and a second contact pair (33, 34), wherein the contact pairs (33, 34) form a three-point contact in the closed position.