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Mechanical Components 1

Overview

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Mechanical Components

This Lecture Will Provide an Overview of

Mechanical Components and ApplicationExamples

Next Lecture Will Go Into More DetailIncluding Analysis and Sizing of CertainComponents

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Testing Machine

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Racing Tricycle

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Racing Tricycle

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Racing Tricycle Completed

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Mechanical Components

Components To Be Covered

Bearings Power Transmission

Belts

Chains Gears

Springs

Power Screws Linkages

Couplings

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Bearings

Allow Relative Rotary or Linear Motion

With Reduced Friction Two Major Types

Plane Antifriction

Others

Air, Magnetic

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Bearings

Plane Bearings

Radial or Thrust orLinear

Bronze, Teflon, Delrin

Lower Cost

Snap-onThrust bearing

Thrust Bearing

Linear Bearing

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Bearings

Antifriction

Radial or Thrust or

Linear Usually Steel

Ball, Roller, Needle

More Expensive

Ball Bearing

Roller Bearing Roller Bearing Dimensions

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Needle Bearings

Examples of Bearings

Air Bearings

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Bearings

Design Issues

Cost Friction

Mounting Sizing

Load

RPM Life

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Bearing Mounting Examples

Bearing MountedPerpendicular to Shaft Rotation

Bearing Mounted Parallelto Shaft Rotation

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Power Transmission

Transmission of Rotary Motion Between

Two or More Shafts Belts

Chain

Gears

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Belts

V-Belts

Relatively Inexpensive Round Belts

Can Make Custom Belt Lengths

Can Make Pulleys

Relatively Inexpensive

Gearbelt or Timing Belts Positive Drive

More Expensive

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Belt ExamplesV-Belts: Timing Belts:

Round Belts:

Solid Vs. Hollow Round Belt Adjustable Length Round Belt

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Chain

Positive Drive

Inexpensive-Bicycle Components More Expensive-Industrial

Components

Single Strand Chains Vs. Double Strand Chains

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Gear Examples

Worm Gears Bevel Gears

Spur Gears Helical Gears

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Gears

Materials

Brass, Steel, Cast Iron, Plastic Wide Range Of Cost

RC Gears: Relatively Inexpensive Industrial Gears: More Expensive

Sensitive To Mounting Distance

Most Hold Center to Center DistanceTolerances

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Springs

Three Major Types

Compression Extension

Constant Force

Many Others

Leaf

Torsional

Others

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Spring Examples Cont.

Torsion Springs:

Constant Force Springs:

Torsion Spring Dimensions

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Springs

Spring Constant

F = KX Example

Compression Springs In Parallel F = (K1 + K2)X

Compression Springs in Series

F = ((K1K2)/(K1+K2))X

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Power Screws

Used For Raising Weights or Exerting

Forces in Machines Square

Acme

Buttress

Ball

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Power Screw ExamplesAcme Power Screw: Ball Power Screws:

Ball Screws

Ball Screw Mounts

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Linkages

Mechanical

Advantage Motion Generation

Mechanical Logic

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Couplings

Join Two Shafts Together

Connection Allow For Misalignment

Allow For Rotation

Absorb Shock