Electric Tool Dual-Bearing Support for Stable Torque Transmission

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electric tools experience instability in operations due to radial and thrust loads applied to the tip tool and driving unit, leading to eccentricity and frictional forces in the transmission mechanism.

Innovation Solution

The electric tool incorporates a transmission mechanism supported by a first and second bearing, with the second bearing in contact with the cover, and a regulating structure to stabilize the output shaft, reducing eccentricity and frictional forces by distributing applied loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single bearing supports the output shaft, then the structure is simple, but radial loads cause eccentricity and operational instability

Engineering Contradiction:
Improvebearing arrangementVSAvoidoperational stability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The output shaft support is segmented into two separate bearings: a first bearing supporting the output shaft at one location, and a second bearing supporting the transmission mechanism and output shaft at another location. This segmentation distributes the radial load across multiple support points, reducing eccentricity and improving operational stability without excessive complexity.

Inventive Principle:
Principle #1Segmentation

2Force

If radial load is applied to the tip tool and driving unit, then the tool can perform work, but frictional forces increase and stability decreases

Engineering Contradiction:
Improveradial load capacityVSAvoidoperational stability
Core Design Contradiction:
ForceVSReliability

Solution Approach 1:

The second bearing acts as an intermediary element between the transmission mechanism and the output shaft. It mediates the radial load by providing an additional support point that reduces the frictional forces between the transmission mechanism and output shaft, thereby maintaining stability while preserving radial load capacity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If the second bearing contacts the transmission mechanism and cover, then frictional forces are reduced, but the structure becomes more complex

Engineering Contradiction:
Improvefriction reductionVSAvoidbearing configuration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The second bearing serves multiple functions simultaneously: it supports the output shaft rotatably, supports the transmission mechanism, and reduces frictional forces between these components. This multi-functionality justifies the additional structural complexity by delivering multiple benefits from a single structural arrangement.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

Stabilizes torque values and reduces frictional forces in the transmission mechanism, ensuring consistent and stable operation by distributing radial and thrust loads effectively.

Implementation Method 1

The first bearing and the second bearing are arranged to support the output shaft (6) rotatably

Methodology Applied
Scientific EffectBall bearing: Ball Bearing

Data Source

PatentEP4582218A1Electric tool
Publication Date: 2025.07.09 PANASONIC HOLDINGS CORP
  • EP4582218A1 patent drawingFigure 1
  • EP4582218A1 patent drawingFigure 2
  • EP4582218A1 patent drawingFigure 3

AI summary

The problem to be overcome by the present disclosure is to contribute to stabilizing operations. An electric tool (1) includes a motor (2), an output shaft (6), a transmission mechanism (3), a first bearing (8A) and a second bearing (8B), and a cover (10B). The output shaft (6) is to be coupled to a tip tool (11). The transmission mechanism (3) is engaged with the output shaft (6) to transmit torque generated by the motor (2) to the output shaft (6). The first bearing (8A) and the second bearing (8B) support the output shaft (6) rotatably. The cover (10B) houses the motor (2), the transmission mechanism (3), the first bearing (8A), and the second bearing (8B). The first bearing (8A) is interposed between the second bearing (8B) and the tip tool (11). The second bearing (8B) is arranged to be in contact with the transmission mechanism (3) and the cover (10B) in a region where the transmission mechanism (3) is engaged with the output shaft (6).