A coupling is a device used to connect two parallel shafts together for the purpose of transmitting power. This coupling transmits rotary motion from one shaft to another. This coupling uses a direct-contact method to rotate two shafts in the same direction. There are three disks mounted on each shaft with a hole bored through the disk that is not concentric to its outer diameter. These three disks are rotated 120° from each other. When the input shaft is rotated, the output shaft turns at the same speed due to the cam interaction of the disks. These steps are meant for those who wish to 3D print and assemble the 6 Disk coupling device. These steps will contain information on how to "post process" and assemble individual parts into the final device.
The 5 different components of the device are as follows;
1. 3 Fused disks (2)
2. Crankshaft (1)
3. Shaft (1)
4. Arrow Pin (2)
5. Base (1)
The Lesson Plan for the 6 Disk Coupling Mechanism is attached to this page for the Instructors who wish to teach students about this device.
Post Processing note: If you are printing with an FDM printer you should expect small ridges on parts where the extruder last touches the piece. Carefully inspect each piece after they are printed for these small imperfections as they will hinder the operation of your device.
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Step 1: Print 6 Disk Coupling Parts
Download the 5 .stl files and upload them to your 3D printer's system. The quality of each part will increase depending on the orientation of the part on the print tray. Print each respective part in the orientations shown in the provided images;
1. 3 fused disks: Horizontal (Face down)
2. Arrow pin: Horizontal
3. Crankshaft: Horizontal
4. Base: Vertical (Bottom down)
5. Shaft: Horizontal
Step 2: Post Process Individual Parts
Based on the brand and quality of your 3D printer, the tolerances of your parts will vary so your parts may not need any refinements, or they may need a lot. The steps we have provided are the techniques we found were useful for making the device run as smoothly as possible. The following tools were used to refine the parts; file (varying sizes), fine sandpaper, Dental picks.
For 6 Disk Coupling: Look for ridges on the outside edges of the disks and sand them down until entire edge is smooth enough for operation. If the edges have small ridges on them they will bind up and not spin easily. Sand the cylindrical and hexagonal faces of the shaft until they mate properly with the base holes and fused disk piece.
Step 3: Assembling the Device
Now that all the parts are refined they are ready to be assembled to create the operation 6 Disk Device.
1. Insert crankshaft through base through hole, while holding the fused 3 disk piece in-between base arches. Push crankshaft through the fused 3 disk piece and second arch of base.
2. Insert arrow pin through rectangular through hole at the end of crankshaft.
3. Repeat step 1 for the shaft piece.
4. Repeat step 2 at the end of the shaft.
Congratulations! You now have a fully functioning 6 Disk Coupling!