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 Shaft has only one gear. Use a Simple Gear Train:

To increase the distance between the input and output shafts and still use small gears
To reverse the direction of the output shaft on a Simple Gear-Pair
To increase or decrease the Torque and Speed at the output-shaft.

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


Note:

1.Only the gears on the input and output shafts change the speed ratio. All other change the rotational direction.
2.The gears not on the input and output shafts are called idle gears or idlers.

Monobloc-scematic

Monobloc Machines

Monobloc machines are frequently used with Filling, Capping, Labelling, Coding, Orientating and many other high speed packaging applications.

The monobloc has a simple gear-train to transmit the motion from one 'head' to the next.

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

Simple Gear Train: Gear-Pair 1

QST14-3-1

Add a Simple Gear-Pair with an External Mesh - see Option 1 Step 14.1

Here, the number-of-teeth are:

T1=20Red-14-1b, T2=40Red-14-2. The Gear Ratio is T1/T2 = 2


The basic rule::

Three Parts, and three Lines, joined together with two Pin-Joints'.

Simple Gear Train: Prepare Gear-Pair 2

QST14-3-2A

Again, we need three Lines, in three Parts. Join the Parts with Pin-Joints. The Pin-Joints must join Points at the end of each Line.


Gear-Pair 2:

Line 1 and Part 1

Line 1 is the CAD-LineRed-14-2 in the Geared-Rocker (output-Gear) of Gear-Pair 1.

QST14-3-2

Gear-Pair 2:

Line 2 and Part 2

This will be the line-of-centres - it is the Line that joins the gear-centres

It is a new Line in the Base-Part.

1.Edit the Base-PartRed-14-3

 

QST14-3-3

2.Add a LineRed-14-1b

It does not matter how long.

IMPORTANT rule: You must MERGE PointRed-14-2 and PointRed-14-3

3.Do Geometry toolbar > Merge-Points
4.Select PointRed-14-2 and PointRed-14-3 at the end of the new LineRed-14-1b
5.Click the graphic-area to complete the merge-points.
6.Close the Part-Editor

QST14-3-4

Line 3 and Part 3

5.Add and Join a PartRed-14-4 to the end of the new Line, with a Pin-Joint.

The length of PartRed-14-4 is not important.

Simple Gear Train: Add Gear-Pair 2

CM-AddGearPair-clear-tags

Element 4 is the Dimension of Line 3

Element 4 is the Dimension of Line 3

Add Gear-Pair 2

1.Add Gear-Pair
2.Click the four elements, in sequence

QST14-3-7

You can see the Gear-Pair 2Red-14-2

 

MechDesigner adds two new gears.

A Simple Gear Train does not need one of the Gears of Gear-Pair 2.

We must hide the Gear on the same shaft centre.

This is a MechDesigner trick.

QST14-4-1

Use the Gear-Pair dialog-box to edit:

1.Module = 3
2.Number-of-teeth Gear 1 = 40 : the same as Gear 2 of Gear-Pair 1
3.Number-of-teeth Gear 2 = 20

 

The image shows the Gear-Pairs Stage 1 and Stage 2: Gear-PairRed-14-1b, Gear-PairRed-14-2

Gear 1 of Gear-Pair 2 is hidden. It is hidden by Gear 2 of Gear-Pair 1

Prepare and Add a Simple Gear Train: Stage 3

CM-AddGearPair-clear-tags

Preparation of model before we add the second Gear-Pair

Preparation of model before we add the second Gear-Pair

Preparation of Model to add the Gear-Pair. 3

1.Edit the Base-Part
2.Add LineRed-14-3

Merge the start-Point of the LineRed-14-3 to the end-Point of the Line-of-Centres in Gear-Pair 2

3.Close the Part-Editor
4.Add Gear-Pair
5.Click the four elements, in sequence

QST14-4-4

 

You can see the new Gear-Pair 3

 

QST14-4-5

To 'hide' the Gear we do not want , use the Gear-Pair dialog to edit the:

1.Module to 3
2.Number-of-teeth on Gear 1 of Gear-Pair 3 to 20 - the same as Gear 2 of the Gear-Pair Stage 2

Also, edit:

3.Number-of-teeth on Gear 2 of Gear-Pair 3 to 40

 

The image shows the Three Gear-Pairs: Gear-PairRed-14-1b, Gear-PairRed-14-2, and Gear-PairRed-14-3

Gear 1 of Gear-Pair 2 is hidden. It is hidden by Gear 2 of Gear-Pair 1
Gear 1 of Gear-Pair 3 is hidden. It is hidden by Gear 2 of Gear-Pair 2

Tutorials and Reference Help Files for MechDesigner and MotionDesigner 14.2 + © Machine, Cam, Mechanism, and Motion Design Software by PSMotion Ltd