Spiroid Provides the Mechanical Advantage

Technical Document Access Below

CASE STUDIES: Helicon vs. Worm

(DOWNLOAD ALL THREE)

CASE STUDY.
DESIGN FOCUS: MAXIMIZE TORQUE

Each gear type offers performance trade-offs depending on its unique design characteristics.  Our goal is to quickly help you evaluate which type of gear technology is best-suited to fit the specific performance requirements of your design project.

What’s in the Case Study?
This case study compares the specific performance characteristics of Helicon and Worm gear sets for design applications that require maximum torque capacity.

CASE STUDY.
DESIGN FOCUS: MINIMIZE SPACE CLAIM
Each gear type offers performance trade-offs depending on its unique design characteristics. As an Engineer, it is your job to evaluate which type of gear technology is best-suited to fit the specific performance requirements of your design project.

What’s in the Case Study?
This case study compares the specific performance characteristics of Helicon and Worm gear sets for design applications that require minimal space claim.

CASE STUDY.
DESIGN FOCUS: MAXIMIZE EFFICIENCY
Each gear type offers performance trade-offs depending on its unique design characteristics. As an Engineer, it is your job to evaluate which type of gear technology is best-suited to fit the specific performance requirements of your design project.

What’s in the Case Study?
This case study compares the specific performance characteristics of Helicon and Worm gear sets for design applications that require maximum efficiency.

WHITE PAPER: High Torque Skew Axis Technical Primer

What’s in the White Paper? 
This guide provides a technical framework that is the foundation of Spiroid’s competitive advantage in the high torque right angle gear marketplace. It covers topics such as:

  • Spiroid Gearset Characteristics
  • Basic Theory
  • Tooth and Blank Proportions
  • Gearset Sizing
  • Application Engineering

APPLICATION DATA SHEET

Would you like to learn how Spiroid Gears can be used in your application? Fill out the contact form and we’ll respond immediately.   You can also call us at 320-762-7133. We’ll get you connected directly to the right person to answer any specific question you might have.

If you have specific application requirements, please fill out and send us the Application Data Sheet.  We’ll be able to serve your inquiry more efficiently.  Thank you.

INERTIA BALANCE IN A GEARBOX

“When such an inertia relationship does not exist between gear and the pinion, at the point of irreversibility (self-locking), intermittent separation of the pinion and gear teeth occur and result in jerky operation because, alternatively, the pinion advances ahead of the gear through the gear clearance and then the descending load causes the gear to catch up with the pinion and engage with impact.”

From ‘Worm-drive Jitters can be Avoided’ by S.J. Mikina

“Stick slip” occurs when a self-locking gear set achieves overhauling mode. That is to say it occurs when the gear, for whatever reason, begins to drive the pinion.

To avoid the stick-slip phenomenon when designing a gearbox, it is important to design it in such a way that the cumulative mass moment of inertia of the input (pinion) side is always greater than the cumulative mass moment of inertia of the output (gear) side.

Achieving non-stick-slip gearbox design

The kinetic energy (KE) of a non-rotating particle of mass m travelling at speed v is represented by KE = ½mv2

Per the law of conservation of energy:

½m1v1 2 = ½m2v2 2(1)

In rotary motion, mass (m) is replaced by mass inertia (I),while velocity (v) is replaced by angular velocity (ω).

Substituting mass inertia (I) and angular velocity (ω) into equation (1)   ½I1ω12 = ½I2ω22(2)

For reduction ratio (R),  ½I1(Rω22 = ½I22)2  I1R2 = I2

Taking efficiency into account, formula ≥ I2(3)

Where I1 = cumulative moment of inertia of the input
I2 = cumulative moment of inertia of the output

The inertias I1 and I2 are calculated for the entire shaft assembly. For example, the output side inertia I2 must include the gear, shaft, bearing races, etc. Essentially, it must include everything rotating at that output speed. Further, while calculating the cumulative output side moment of inertia, it is also important to consider the maximum output torque. See below:

I2 = Igear + Ishaft + Ibearing races + Ioutput torque + etc.

THEORETICAL PERFORMANCE RATINGS

This ratings data represents theoretical performance values for a given size and ratio range – at various speeds. These values are not intended to represent actual gear sets that Spiroid maintains in stock. While Spiroid does maintain an inventory of cutting tools, our customer’s specific applications will determine whether ‘Stock’ or ‘Custom’ cutting tools are appropriate.  Please contact us directly for further information (320) 762-7133.