Rotary Knife Blade Gear Geometry for Lower Wear and Vibration

Solution Overview

Problem

Conventional power operated rotary knives face challenges in increasing rotational speed while minimizing heat generation, vibration, and wear rates, which affect operational efficiency and component lifespan during cutting and trimming operations.

Innovation Solution

The design incorporates an annular rotary knife blade with a convex arcuate surface and overlapping gear teeth that reduce gear reaction forces and wear rates, along with a lubrication system to minimize heat and vibration, allowing for higher rotational speeds and extended operational life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If rotational speed of the rotary knife blade is increased to improve cutting efficiency, then productivity increases, but heat generation and vibration increase leading to accelerated wear and reduced component lifespan

Engineering Contradiction:

Improvecutting efficiencyVSAvoidcomponent lifespan

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies spheroidality by replacing conventional straight gear teeth with arcuate (curved) gear teeth that follow a circular path. This curvature allows the gear teeth to engage more smoothly and distribute reaction forces more evenly throughout the gear mesh, reducing peak stresses and vibration. The arcuate geometry of the gear teeth in the rotary knife blade creates a more uniform force distribution during rotation, which reduces vibration and heat generation while maintaining high rotational speeds, thus improving both productivity and reliability

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Ease of manufacture

If conventional straight gear teeth are used in the rotary knife blade, then manufacturing is simpler, but gear reaction forces and wear rates are high reducing operational life

Engineering Contradiction:

Improvegear tooth fabricationVSAvoidoperational life

Core Design Contradiction:

Ease of manufactureVSDuration of action of moving object

Solution Approach 1:

The patent replaces straight gear teeth with arcuate (curved) gear teeth that follow a circular path. This curvature allows the gear teeth to engage more smoothly and distribute reaction forces more evenly throughout the gear mesh, reducing peak stresses and vibration. The arcuate geometry of the gear teeth in the rotary knife blade creates a more uniform force distribution during rotation, which reduces vibration and heat generation while maintaining high rotational speeds, thus improving both productivity and reliability

Inventive Principle:

Principle #14Spheroidality (Curvature)

3Speed

If high rotational speeds are achieved without design modifications, then cutting speed increases, but heat generation accelerates wear and requires more frequent maintenance

Engineering Contradiction:

Improverotational speedVSAvoidwear rate

Core Design Contradiction:

SpeedVSLoss of substance

Solution Approach 1:

The patent applies spheroidality by replacing conventional straight gear teeth with arcuate (curved) gear teeth that follow a circular path. This curvature allows the gear teeth to engage more smoothly and distribute reaction forces more evenly throughout the gear mesh, reducing peak stresses and vibration. The arcuate geometry of the gear teeth in the rotary knife blade creates a more uniform force distribution during rotation, which reduces vibration and heat generation while maintaining high rotational speeds, thus improving both productivity and reliability

Inventive Principle:

Principle #14Spheroidality (Curvature)

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 enhances operational efficiency by reducing wear rates and heat generation, leading to longer component lifespan and increased rotational speed without compromising the integrity of the rotary knife blade and blade housing.

Implementation Method 1

along with a lubrication system to minimize heat and vibration

Methodology Applied

Scientific EffectLubrication: Lubrication

Implementation Method 2

The design incorporates an annular rotary knife blade with a convex arcuate surface and overlapping gear teeth that reduce gear reaction forces and wear rates, along with a lubrication system to minimize heat and vibration

Methodology Applied

Scientific EffectVibration: Vibration

Data Source

PatentUS11839988B2Power operated rotary knife

Publication Date: 2023.12.12 BETTCHER IND INC

AI summary

A power operated rotary knife including an annular rotary knife blade supported for rotation in a blade housing. The rotary knife blade including a body and a blade section extending from the body. The body includes an outer wall including an arcuate surface having an upper region extending from a first upper end portion to a second intermediate portion and a lower region extending from the second intermediate portion to a third lower end portion. A plurality of gear teeth extend downwardly from the upper end of the body, each of the plurality of gear teeth including an outer peripheral face forming a portion of the upper region of the arcuate surface of the outer wall. The body outer wall includes a bearing surface having a lower bearing face in the lower region of the arcuate surface and an upper bearing face in the upper region of the arcuate surface.