Clutch System

As it was mentioned earlier, our system must be able to activate and deactivate the shafts which were connected to each other using gears. To solve this, a clutch-type system was implemented, very similar to that found in cars.

This system consisted mainly of 4 elements. A gear that had a "toothed" hub to allow the "teeth" of the sleeve to fit onto it. The sleeve, which is the most important element of the clutch, allowed the transmission of movement between the gear and the shaft. This component essentially has a sleeve to fit over the "toothed" hub of the free gear and the teeth of the hub gear. The system had 2 main requirements.

First, that the sleeve must always be in contact with the hub gear. To achieve this the tooth profiles for the inner portion of the sleeve and the hub gear must be the same.

Second, this component should be able to slide on the shaft to get in contact with the gear. The point of contact between the gear and the sleeve would likewise be a series of teeth, which have the particularity of being spaced enough to be able to mesh the teeth of the sleeve with those of the gear at the moment it is rotating, without this spacing, when rotating the two elements (gear and sleeve) it would be very complicated to make them fit.

Note that the section in the sleeve for the hub must be longer than the one of the gear in order to keep contact at all times with the hub of the shaft.

The third element was the hub gear, which, like the free gear, had a series of "teeth" to fit the sleeve, the difference was that these teeth do not need to be spaced, as they will always be in contact with the teeth of the sleeve.

The last component of this system was the actuator. For this, a small independent system was designed and modeled, consisting of a servo motor, a rack and a pinion. Together, these allowed us to transform the rotational movement of the servo motor into a linear movement, which was the type of movement necessary to move the sleeve.

In order to maintain contact with the sleeve, a cylinder-shaped fastener was added to the end of the rack, which would allow the sleeve to rotate, without the need for it to rotate.