Rotating Push Handle Control Logic to Prevent Tool Misstart

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Solution Overview

Problem

The accidental triggering of a motor switch during the retraction of a push rod in electric gardening tools poses a significant safety hazard to operators, as it can start the tool while the operator is too close, leading to potential injury.

Innovation Solution

An electric tool with a push handle component that can rotate between working and non-working positions, featuring a signal unit to feed back different state signals and a control circuit that adjusts motor starting logic based on the handle's position, incorporating varying trigger times and signal feedback to prevent accidental startup in the non-working position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the push handle component is made rotatable for space-saving during transportation, then the transportation space is reduced, but the operator may accidentally trigger the motor switch during retraction causing safety hazards

Engineering Contradiction:
Improvetransportation spaceVSAvoidsafety hazard
Core Design Contradiction:
Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

The patent implements a signal unit that detects the position of the push handle component and feeds back position information to the control circuit. The control circuit uses this feedback to determine whether to enable motor starting, thereby preventing accidental startup during retraction while allowing normal operation when the handle is in the working position area.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The control circuit is configured to preliminarily determine the position state of the push handle component before allowing motor startup. By checking the position signal in advance, the system prevents accidental motor activation during the retraction process, ensuring safety before the actual starting action occurs.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If the control circuit enables motor startup in all positions for operational flexibility, then the ease of operation is improved, but the safety risk increases due to potential accidental startup during retraction

Engineering Contradiction:
Improveoperational flexibilityVSAvoidsafety risk
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent applies different control characteristics to different spatial regions of the push handle component. When the handle is in the working position area, the motor can be started normally for operational flexibility. When the handle is in the non-working position area (during retraction), the motor startup is restricted to prevent accidental activation, thus achieving local differentiation of control quality.

Inventive Principle:
Principle #3Local quality

3Productivity

If the trigger holding time is shortened for quick startup, then the productivity is improved, but the probability of accidental triggering increases

Engineering Contradiction:
Improvestartup speedVSAvoidaccidental triggering probability
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The control circuit performs a preliminary position check before enabling the motor startup function. This preliminary action ensures that even if the trigger is pressed quickly, the motor will only start if the push handle is in the correct working position area, thereby maintaining quick startup capability while preventing accidental triggering during retraction.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4582887A1Electric tool
Publication Date: 2025.07.09 POSITEC POWER TOOLS (SUZHOU) CO LTD
  • EP4582887A1 patent drawingFigure 1
  • EP4582887A1 patent drawingFigure 2~3
  • EP4582887A1 patent drawingFigure 4

AI summary

The invention relates to an electric tool, and a control method for a motor of an electric tool. A signal unit feeds back a first state signal when a push handle component is in a working position area and the push handle component is locked relative to a main unit; and the signal unit feeds back a second state signal when the push handle component is in a non-working position area. When receiving the first state signal, a control unit controls a motor to be started according to a first control logic; and when receiving the second state signal, the control unit controls the motor to be started according to a second control logic, where the second control logic is different from the first control logic. In this way, when the push handle component is in the non-working position area, a different starting logic is used to control the motor to be started, so that a probability that a user accidentally starts an electric tool because of accidentally triggering a switch assembly is reduced, and a use risk of the user is reduced, thereby improving safety of the electric tool.