Resilient Contact Arms for Oil Pressure Switch Wear Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing oil pressure switches in motor vehicle technology experience accelerated wear due to high or fluctuating engine oil pressures, which directly transmit to rigid contact elements, leading to premature wear and frequent replacement.

Innovation Solution

A pressure switch design featuring a contact piece with resilient contact arms and shoulders, where the contact pressure remains constant and decoupled from media pressure, utilizing a plunger and parameter spring to manage contact with a contact plate, ensuring the contact force does not exceed a predefined value, even at high pressures or fluctuations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If rigid contact elements are used to transmit engine oil pressure directly, then the pressure switch can respond to pressure changes, but the contact elements experience accelerated wear due to high pressures and high-frequency pressure fluctuations

Engineering Contradiction:
Improveresponse speed to pressure changesVSAvoidservice life of contact elements
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The contact piece is designed with resilient contact arms that change their mechanical parameters (flexibility, contact pressure) based on the applied media pressure. At low pressures, the resilient arms remain flexible to allow contact closure. At high pressures, the resilient arms deform to limit contact pressure to a predefined value, preventing wear while maintaining electrical contact functionality.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The contact piece transitions from a static rigid structure to a dynamic resilient structure that adapts its contact pressure based on operating conditions. The resilient contact arms dynamically adjust their deformation state according to the media pressure, allowing the system to respond to pressure changes while protecting contact elements from excessive wear.

Inventive Principle:
Principle #15Dynamics

2Reliability

If the contact area is designed to maintain constant contact pressure independent of media pressure, then wear is reduced, but the contact force must be decoupled from the media pressure transmission

Engineering Contradiction:
Improveservice life of contact elementsVSAvoidcomplexity of contact piece structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The contact piece is segmented into multiple resilient contact arms with contact nubs, rather than a single rigid contact element. This segmentation allows each contact arm to independently deform and limit contact pressure, distributing the mechanical stress and enabling the decoupling of contact pressure from media pressure while maintaining electrical contact functionality.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The resilient contact arms act as intermediaries between the media pressure transmission path and the electrical contact elements. These intermediaries absorb and limit the transmission of high media pressures to the contact elements, allowing constant contact pressure to be maintained while preventing wear from excessive forces.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If multiple contact arms with contact nubs are used to limit contact pressure, then wear is reduced, but the manufacturing precision requirements increase

Engineering Contradiction:
Improveservice life of contact elementsVSAvoidprecision of contact arm geometry and bending length
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The resilient contact arms are designed with specific geometric parameters (bending length, cross-section, material properties) that determine their spring characteristics. By carefully selecting these parameters, the contact arms naturally limit contact pressure to predefined values through their elastic deformation, reducing wear while maintaining manufacturability through standardized spring design principles.

Inventive Principle:
Principle #35Parameter changes

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 significantly extends the service life of contact elements by maintaining a constant contact pressure, reducing wear and improving electrical properties, while maintaining reliable operation under varying oil pressures.

Implementation Method 1

the contact arm has at its beginning a contact shoulder which has no contact with the contact plate in a pressureless state and is in contact with the contact plate from a predetermined pressure of a medium

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

a parameter spring, the plunger and the parameter spring being arranged in such a way that the plunger and the contact piece are positioned at a lower stop in the pressureless state and move towards an upper stop as the pressure increases

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP2410545B1Pressure switch
Publication Date: 2014.02.26 FEP FAHRZEUGELEKTRIK PIRNA GMBH
  • EP2410545B1 patent drawingFigure 1~2
  • EP2410545B1 patent drawingFigure 3~4

AI summary

Pressure switch (1), in particular oil pressure switch, which has as contact elements a contact plate (3) and a switching element (2), wherein the switching element (2) has at least one contact area which in a pressureless state has no contact with the contact plate (3) and is in contact with the contact plate (3) from a predetermined pressure of a medium, and wherein the switching element (2) and the contact plate (3) are shaped such that the contact force of the contact area of ​​the switching element (2) on the contact plate (3) does not exceed a predefined value regardless of the medium pressure.