FIXED CENTRES:

One Gear-Pair
Two or more Gear-Pairs, including
oSimple Gear-Train
oCompound Gear-Trains
oReverted Gear-Trains

tog_minus        One Gear-Pair

Fixed Gear Centres

External

Gear 1 < Gear 2

External

Gear 1 > Gear 2

Internal

Gear 1 < Gear 2

Internal

Gear 1 > Gear 2

Gears - Fixed Centres- External Mesh - Decreasing Gear Ratio

Gears - Fixed Centres - External Mesh - Increasing Gear Ratio

Gears - Fixed Centres - Internal Mesh - Increasing Gear Ratio

Gears - Fixed Centres - Internal Mesh - Decreasing Gear Ratio

tog_minus        Simple Gear-Trains

Schematic of Simple Gear Train

Schematic of Simple Gear Train

A Simple Gear-Train is a number of Simple Gear-Pairs in series. Each rotating shaft has only one gear.

Simple Gear-Trains are used to:

Increase the distance between the input and output shafts, so it is possible to use a number of smaller gears than when you use one gear-pair
Reverse the direction of the output shaft of a Simple Gear-Pair

The image to the left shows a schematic of a 'Simple Gear Train'.


Notes for Simple:

Gears that are not on the input and output shafts do not change the speed ratio. They only change the direction of rotation.
The gears between the input and output shafts are 'idle gears' or 'idlers'.

Monobloc-scematic

'Monobloc Machines'

This is a schematic of the gears you frequently find on a 'Monobloc' machine. Monobloc are often use for Filling, Capping, Labelling, Coding, Orientating and many other high-speed packaging applications.

Monobloc machines use Simple Gear-Trains to transmit the motion from one 'wheel', or 'head' to the next.

See Also: the YouTube Video: http://youtu.be/fvRp2lC1aXw


Video:

tog_minus        Compound Gear-Trains

Schematic of Compound, three stage, Gear Train.

Schematic of Compound, Three-Stage, Gear Train

A 'Compound Gear Train' has at least:

two Gear-Pairs
one shaft with more than one gear

Compound Gears are used to:

Increase the distance between the input and output shafts and still use small gears
Dramatically reduce the speed between the input and output shafts
Give 'difficult' gear ratios

The image to the left shows a Compound Gear Train. There is more than one gear-pair and two shafts have two gears.

Therefore, it agrees the definition of the Compound Gear Train.

tog_minus        Reverted Gear-Pairs

Schematic of Compound, three stage, Gear Train.

Schematic of Compound, Three-Stage, Gear Train

A 'Reverted Gear Train' has:

two Gear-Pairs
two shafts
the input and output shafts are co-axial
the two shafts are usually co-axial

It is a Compound Gear with, two Gears-Pairs, and a special condition that makes the total number of teeth of the first gear-pair equals the number of teeth of the second-gear-pair, when the module is the same.

The image to the left shows a Reverted Gear Train. There is more than one gear-pair, two shafts, and the input and output shafts are co-linear.

Therefore, it agrees the definition of the Reverted Gear Train.

See Also: Simple Gear-Pair, Simple Gear-Trains, Planetary Gear-Trains

 

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd