Retaining Tool for Bolt Assembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

During automotive assembly, intermediate elements like bushes and washers tend to slide off bolts due to play, causing inefficiencies and requiring additional labor or costly welding, which introduces material and weight to the vehicle.

Innovation Solution

A retaining tool with engagement members that temporarily secure intermediate assembly elements onto threaded fasteners, allowing single-person assembly without permanent attachment, by being mountable and removable transversely to the fastener axis, reducing the risk of elements falling off during assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If intermediate elements are permanently fixed to components before assembly, then they will not fall off during assembly, but assembly time increases and cost increases

Engineering Contradiction:
Improveintermediate element retentionVSAvoidassembly time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

A retaining tool acts as a temporary intermediary device that holds intermediate elements on fasteners during assembly. The tool includes engagement members that fit over the fastener and retain the intermediate element, allowing single-person assembly without permanent pre-attachment, thereby reducing assembly time while preventing element loss.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If welding is used to prevent intermediate elements from falling off, then retention is ensured, but cost increases and additional material is added to the vehicle

Engineering Contradiction:
Improveintermediate element retentionVSAvoidvehicle material
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The retaining tool serves as a temporary intermediary holding mechanism during assembly, eliminating the need for permanent welding or additional material attachments to the vehicle. The tool is removed after assembly, leaving no additional material in the final product.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The retaining tool is a temporary, disposable assembly aid that is used only during the assembly process and then removed. It does not become part of the final vehicle structure, avoiding permanent material addition while ensuring intermediate elements are properly retained during assembly.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Reliability

If two assembly personnel are used to prevent intermediate elements from falling off, then retention is ensured, but labor efficiency decreases

Engineering Contradiction:
Improveintermediate element retentionVSAvoidassembly efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The retaining tool acts as a mechanical intermediary that performs the retention function automatically during assembly. This eliminates the need for a second worker to manually hold intermediate elements, allowing single-person operation while maintaining reliability.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The retaining tool is self-retaining through its engagement members that automatically secure intermediate elements on fasteners as they are inserted. The tool performs its own retention function without requiring additional human intervention, enabling single-person assembly operations.

Inventive Principle:
Principle #25Self-service

4Device complexity

If no retaining mechanism is used, then assembly is simpler, but intermediate elements fall off due to play between elements and fasteners

Engineering Contradiction:
Improveassembly process complexityVSAvoidintermediate element retention
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The retaining tool provides a simple intermediary mechanism that fits over the fastener and retains the intermediate element during assembly. The design is straightforward with engagement members that simply engage the fastener and hold the element, adding minimal complexity while ensuring reliable retention.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2644913B1Assembly method using retaining tool
Publication Date: 2019.10.30 NISSAN MOTOR MFG (UK) LTD
  • EP2644913B1 patent drawingFigure 1~2
  • EP2644913B1 patent drawingFigure 3~4
  • EP2644913B1 patent drawingFigure 5a~5d

AI summary

A tool (1) retains a bush (3) on each of at least two bolts (5), for example during assembly of parts (9) to vehicle engines. The tool includes at least two spaced engagement members (11, 13, Fig. 1), which define a slot (14, Fig. 1), which is open at one end (14L, Fig. 1), and may be tapered and/or curved. Hence, the tool (1) can be mounted on, and removed from, the bolts (5) in a direction transverse to the longitudinal axes of the bolts. These axes may be parallel. Numeral 15 (Fig. 1) denotes a handle. The tool may be moulded plastic, stamped or cut metal, or of composite construction. The engagement members are arranged to locate between teeth on the bolt thread(s). Several bolts may engage in one or each slot. An assembly system and method are also disclosed.