Starter Engaging Relay Cover Rupture Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Engagement relays for internal combustion engine starters are prone to cover rupture under extreme loads, leading to potential short circuits between the relay pin connected to the battery and the body.

Innovation Solution

The relay cover is designed using elastically deformable plastic with an axially rigid edge zone and optional stiffening inserts to absorb sudden loads without breaking, ensuring secure fixation and flexibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the relay cover is made of rigid material to maintain fixed position of relay bolts, then the clamping force is maintained, but the cover may rupture under extreme sudden loads

Engineering Contradiction:
Improveclamping forceVSAvoidresistance to sudden loads
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent applies parameter changes by transitioning from a completely rigid material to an elastically deformable plastic material. This change in material parameter allows the cover to maintain sufficient clamping force for normal operation while acquiring the ability to absorb extreme sudden loads through elastic deformation, thereby preventing rupture and improving reliability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs composite materials by combining an elastically deformable plastic base material with stiffening inserts made of different material properties. This composite structure allows the cover to exhibit both flexibility for absorbing sudden loads and localized rigidity for maintaining clamping force, resolving the contradiction between these two requirements.

Inventive Principle:
Principle #40Composite materials

2Reliability

If the relay cover is made of flexible plastic to absorb sudden loads, then the reliability is improved, but the clamping force may be compromised

Engineering Contradiction:
Improveresistance to sudden loadsVSAvoidclamping force
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies local quality by implementing stiffening inserts at specific locations where relay bolts are clamped to the cover. These localized rigid elements ensure that the clamping force is maintained at critical interfaces, while the rest of the cover remains flexible to absorb sudden loads, thus resolving the contradiction between flexibility and clamping strength.

Inventive Principle:
Principle #3Local quality

3Strength

If the cover is designed to be completely rigid to prevent breakage, then the strength is improved, but the ability to absorb sudden loads through deformation is lost

Engineering Contradiction:
Improveresistance to breakingVSAvoidload absorption capacity
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The patent changes the material parameter from completely rigid to elastically deformable plastic, enabling the cover to absorb sudden loads through controlled elastic deformation. This parameter change allows the cover to maintain strength while gaining load absorption capacity, preventing catastrophic failure.

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 maintains clamping force and absorbs extreme loads through elastic deformation, preventing cover rupture and short circuits, thus enhancing reliability and safety.

Implementation Method 1

the flexibility of the cover ensures that extreme loads, in particular loads that act suddenly on the respective relay bolt, can be at least partially absorbed by corresponding elastic deformation of the cover

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

an actuating magnet (4) that acts on a magnet armature (5) in a fixed position

Methodology Applied
Scientific EffectMagnetic force: Magnetism

Data Source

PatentEP2140131B1Engaging relay for starter
Publication Date: 2014.04.09 ROBERT BOSCH GMBH
  • EP2140131B1 patent drawingFigure 1~3

AI summary

An engaging relay 1 for starters for internal combustion engines has a relay cover 8 on the front side of a relay housing 2 that encompasses the armature 5, said cover being made of a material in the region of the circumferential edge zones of openings 16, 17 for relay bolts 12, 13 that are to be axially braced against the relay cover 8, said material being more rigid in compression than in the remaining cover region.