Knex Pull-back Car, Ball Machine Element

by mathsboy314 in Living > LEGO & K'NEX

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Knex Pull-back Car, Ball Machine Element

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This element is a lever and a car. The lever engages a motor which pulls the car to the top of a ramp. Then the ball gets on the car and drives back down the ramp.

This was used in my most recent ball machine: https://youtu.be/-u3Mi7ozmv0?t=25

Frame

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Lever Axel

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Combining Steps

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Ball Arm

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This is where the ball waits while the car is getting pulled back.

Lever Counterweight

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Motor Axel

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Engaging Gear

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This gear will be attached to the lever. This is what engages the motor to the rest of the mechanism.

Further Frame

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This holds the lever so it doesn't tilt too far backwards.

Disengaging Gears

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When the lower gear has does 3/4 of a revolution, it will force the lever to tilt back. This will disengage the motor, release the ball, and let the car go down the ramp.

Even Further Frame

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This stops the Disengaging Gears from rotating too far backwards.

Reel

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This is what pulls the car up the ramp.

​Final Frame

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This helps the ball land properly on the car.

The Car

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Once you're done, tie this to the Reel, and build a track for the car to go on.