Simple Gear-Trains

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Simple Gear-Trains

Simple Gear Trains

Schematic of Simple Gear Train

Schematic of Simple Gear Train

A Simple Gear-Train has two or more Gear-Pairs that you connect in series. The Driven-Gear of one Gear-Pair becomes the Driving-Gear of the next Gear-Pair in the series, and so on in the series.

Use a Simple Gear-Train to:

increase the distance between the input and output shafts and still use small gears

reverse the direction of the output shaft on a Simple Gear-Pair

increase or decrease the Torque and Speed at the output-shaft.

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


Note:

1.The Driving-Gear on the first Gear-Pair and the Driven-Gear or the last Gear-Pair in the series of gears control the gear and speed ratio.

2.All other gears are idle gears or idlers - they do not affect the overall Gear-Ratio.

Schematic of a Monobloc machine.

Schematic of a Monobloc machine.

Application of Simple Gear-Train - a Monobloc Machine

Monobloc machines include Filling, Capping, Labeling, Coding, Orientating and many other high-speed applications.

The Monobloc uses a simple gear-train to transmit the motion from shaft to shaft.

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

 

Gear-Pair 1

Gear-Pair with Fixed Centers

Gear-Pair with Fixed Centers

Add a Gear-Pair

1.Do Add a Gear-Pair with Fixed-centers

2.Edit the Gear-Pair.

Open the Gear-Pair dialog:

3.Edit the Gear 1 and Gear 2:

number-of-teeth, Z1=20 Red-14-2

number-of-teeth, Z2=40 Red-14-3

4.Edit the Module:

Module = 2

Gear Ratio is Z1/Z2 = 2 ; Distance between Gear Axes = 60mm

Gear-Pair 2 : PREPARATION

Line-1(5) in Part-1(4)

Line-1(5) in Part-1(4)

Line 1 in Part 1 :

The Driven-Gear of Gear-Pair 1 will be the Driving-Gear of the Gear-Pair 2.

LineRed-14-5 in PartRed-14-4 - see Gear-Pair 1, above

Line 2 in Part-2 Before you do Merge-Points

Line 2 in Part-2 Before you do Merge-Points

Line 2 in Part 2 (the Base-Part)

1.Edit the Base-Part

2.Geometry toolbar > Add LineRed-14-1b


IMPORTANT Rule for a Gear-Train: You must MERGE PointRed-14-3 and PointRed-14-4.

To merge the Points:

Either

a)Drag to add LineRed-14-1b - hover above PointRed-14-3 to merge PointRed-14-3 and PointRed-14-4 automatically.

OR

a)Drag to add the LineRed-14-1b (near to PointRed-14-3)

Geometry toolbar > Merge-Points

a)Click the end-PointRed-14-3 of the Line-of-Centers of Gear-Pair 1

b)Click the start-PointRed-14-4 of LineRed-14-1b

c)Click the graphic-area

3.Geometry toolbar > Add DimensionRed-14-2

a)Add a DimensionRed-14-2 to LineRed-14-1b (the length is not important)

4.Close the Part-Editor.

Line 3 in Part 3 (new Part)

Line 3 in Part 3 (new Part)

Line 3 in Part 3 :

A new Part - it will be the Driven-Gear.

1.Click Kinematics-toolbar > Add Part: Drag to add PartRed-14-6

2.Click Kinematics-toolbar > Add Pin-Joint :

a)Click the start-Point of CAD-Line in PartRed-14-6

b)Click the end-Point of LineRed-14-1b in the Base-Part.

The length the CAD-LineRed-14-7 in PartRed-14-6 is not important.

Gear-Pair 2 : ADD GEAR-PAIR

GST-14.A2-05

You can now add Gear-Pair 2

1.Click Machine-elements toolbar > Add Gear-Pair

2.Click the elements, Red-14-5Red-14-7Red-14-1bRed-14-2 from top to bottom - refer to Preparation images, above

3.Click OK-tiny-11-15  at the bottom of the Command-Manager.

 

GST-14.A2-06

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

There are two new gears.

However, a Simple Gear Train has three gears.

You must edit Gear-Pair 2 so that its Gear-1 has an equal number-of-teeth to the Gear-2 of the Gear-Pair 1.

 

GST-14.A2-07

Use the Gear-Pair dialog 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 is Gear-PairRed-14-1b and Gear-PairRed-14-2

The position of Gear 2 of Gear-PairRed-14-1b is identical to Gear 1 of Gear-Pair Red-14-2.