CVT Transmission Demonstration Model

This is a compact CVT (Continuously Variable Transmission) demonstrator designed to illustrate the basic operating principle of CVT technology.

The wheel component can be printed in TPU. A firmer TPU is recommended, as it provides better grip and reduces slipping during operation.

In addition to the 3D-printed parts, the following components are required:

• 12 × M3 heat-set inserts

• 12 × M3 screws, 8 mm long

• 4 × mr74zz ball bearings

• 1 × micro DC motor

• 1 × 4.5 V power supply

All off-the-shelf components used in this project are available from the Bambu Lab website. Their dimensions were used as reference when designing the model.

How It Works

The transmission ratio can be adjusted by sliding the pusher along the mechanism. As the pusher changes position, the effective contact diameter changes, resulting in a different gear ratio.

The spinners are designed to make this change clearly visible and help demonstrate how the transmission ratio varies during operation.

Assembly guide

This model needs several heat-set inserts, so I recommend putting them in place first.

Let's start the assembly

Put the wheel and pusher onto the pin.

Put the previous assembly onto its place on the stand and fasten it.

Put the upper rod through the holes and lock it in place with the screws.

Put the ball bearings into their place on the holders. You will have to do this four times.

Put the cone rods into the cones. You will have to do this twice.

Put the cones through the holes of the ball bearings. You will have to do this twice.

Put the spinners into their places on the ends of the cones.

Put the big gear on the 1st cone.

Put the DC motor in place.

Put the small gear onto the DC motor.

Put the cones in place and fasten them.

Put the power supply in place and connect the electronics.