Food Processor Safety Coupling With Guide Pin Disengagement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing food preparation appliances with rotary tools and drive shafts pose a safety risk due to stable coupling when the lid is held upside down without the container, leading to potential user injury upon motor activation.

Innovation Solution

A food preparation appliance design featuring a guide pin and driver coupling that allows torque transmission but not radial support, preventing stable engagement when the container is absent, ensuring safety by disengaging the rotary tool if the lid is held incorrectly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If a cross-shaped indentation coupling is used between the driver and rotary tool hub, then stable engagement is achieved, but user safety deteriorates due to risk of injury when the lid is held upside down without the container

Engineering Contradiction:
Improveengagement stabilityVSAvoiduser injury risk
Core Design Contradiction:
Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The coupling function is segmented into two independent parts: torque transmission (via conjugate shapes) and radial support (via guide pin). This segmentation allows the torque transmission to occur without stable radial engagement, preventing the tool from remaining coupled when the lid is inverted, thus eliminating the safety hazard while maintaining functional capability during proper use.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The radial support function is extracted from the driver-tool coupling and transferred to the guide pin mechanism. By removing the radial support capability from the conjugate shapes coupling, the invention ensures that torque can be transmitted only when the guide pin provides proper radial alignment through the container, preventing accidental operation when the lid is held upside down without the container.

Inventive Principle:
Principle #2Taking out (Extraction)

2Stability of the object's composition

If radial support is provided through the driver-tool coupling, then stable positioning is achieved, but the ability to transmit torque without stable engagement is lost

Engineering Contradiction:
Improveradial positioningVSAvoidtorque transmission capability
Core Design Contradiction:
Stability of the object's compositionVSPower

Solution Approach 1:

The functions of radial positioning and torque transmission are separated into different mechanical elements. The guide pin through the hub and driver provides radial positioning, while the conjugate shapes between the driver and hub provide torque transmission. This segmentation allows each function to be optimized independently, enabling torque transmission only when proper radial alignment is established by the guide pin.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The guide pin acts as an intermediary element that mediates between the container and the rotary tool assembly. It provides the necessary radial alignment and support, allowing the conjugate shapes to transmit torque effectively only when the tool is properly positioned within the container, thus enabling conditional torque transmission based on correct assembly.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP1806079B1Cooking appliance equipped with a safety coupling between a drive shaft and a rotating tool
Publication Date: 2008.10.22 SEB SA
  • EP1806079B1 patent drawingFigure 1
  • EP1806079B1 patent drawingFigure 2
  • EP1806079B1 patent drawingFigure 3~4

AI summary

The food processor has a base (1) containing a vertical shaft (10). The hub (20) of the cutter (2) is threaded over this and the drive shaft (4) of a drive in the lid is then fitted, so that corresponding sections (200, 201; 400, 401) on the cutter hub and drive shaft lock together.