The kinematics aspects of the project include a four-bar crank rocker, Gear train, and a slider crank on the rocker.
A big challenge was how to release the card with the simple rotating motion of the crank.
As it can be seen from the Solidworks assembly. The four-bar crank rocker is the skeleton of the mechanism. The base of the crank is grounded to a shaft which allows it to rotate about that point. Crank is connected to a gear which is rotated as the crank is rotated. Additionally there is a gear train connecting to the shaft which connects to the rocker. The rotating end gear (smallest gear) causes the shaft to rotate which causes the slider crank mechanism to operate. Slider crank is attached to and slides on the rocker and performs the releasing of the card. The sliding motion on the rocker creates a Coriolis effect.
Materials:
The materials used in the project were:
¼” Acrylic
5mm Bearings
3D printed Material
5 mm diameter metal Shafts
All of the links were connecting using shafts and bearings provided. The bearing provided for a smooth rotating motion. The linkages were made out of acrylic and were laser cut. The card holder and the slider crank were both made out 3D printed material.
Sample Parts and Prototypes :
The slider which releases the card from the stack has sand paper at the end of it to help grip on to the card well. The slider went through multiple prototypes before it was finalized . The angle at which the slider contacted the cards was important because it could restrict the outward motion of the cards.
Card holder at the tip of the rocker.
Our initial idea was to use a gear belt between the largest gear and the smallest gear. However, this would have more room for error because any potential incorrect dimensions could cause the belt to skip teeth and not rotate properly.