Having formulated a clear vision for the sustainable coffee solution, the ideation phase starts with brainstorming. The ideas are evaluated and elaborated further starting with figuring out the mechanical working principles. Lastly the exterior appearance is designed, leading into a final concept.
Ideas to concept
Mechanical working principles
For the coffee machine under design, new mechanical working principles are sought as a system is needed to feed and extract the pods in and out of the machine.
For the first concept, the focus was on downscaling the full automatic process in more expensive machines to make it more appealing for a home setting. The concept developed worked as follows: A bag of pre-portioned ground coffee sealed in plastic. As the user, you need to rip open the little bag with coffee, and the contents they pour into the hopper of the machine. Following this, by means of a lever pull, the ground coffee is compressed into the brewing chamber. Then, when the appropriate button is pressed on the machine, the coffee will be made. Finally, the waste coffee ground is stored in a container that needs to be cleaned occasionally. However, the downside of this system is that it sacrifices user comfort.
For another idea, inspiration is taken from the American weapons industry. Specifically, the way pump-action shotguns load and extract their shells. Since the shells used in shotguns are also made of plastic, sometimes even biodegradable plastic, the mechanism used in these shotguns could be adapted to coffee machines. Drawings are created to work the mechanism out more. Version one aims to replicate the shotgun mechanism closely, with a bolt and hook mechanism. The bolt (red) fits nicely into the hollow cavity of the pod. Since the hook (green) is spring loaded, it will move out of the way when the pod is fed into the mechanism. When the pod is inserted into the mechanism, the pod is securely held in place. Then, when the bolt moves back, the pod is pulled back as well. At the end of the pulling motion, a small ramp ensures that the pod is ejected to the side. One issue with this mechanism is that the pod is not supported on the outside of the bolt, and that the pod cannot be made with injection molding techniques. Manufacturing the pod would require the use of blow molding. Blow molding is a process used to create hollow plastic products, such as bottles and containers.
Version two incorporates a more streamlined bolt, with less sharp corners, ribs, and equal wall thickness throughout. The mechanism and how it functions have not changed compared to version one.
For version three, the issue of the pod not being supported on the sided is fixed, by changing the shape of the bolt receiver. The rest of the bolt remains the same as in concept two. The mechanism and how it functions also remain the same as in concept two.
As a proof of concept, a LEGO model has been created to show how the pods would be fed and extracted.
Shotgun working principle
Version one, two, and three of Franchi
Concept 3
The idea behind this concept is to combine the familiarity of the popular senseo machines, and combine that with a layer of innovation. From the senseo machines, the idea of a latch to open and close the machine was taken. Moreover, by adapting a similar latching system as the Smith and Wesson 1870 Schofield model 3 revolver, a hybrid version of a latching system was created. The benefit of this latching system is that it allows for very high pressures inside the brewing chamber, since the latching lever is in pure tension. Furthermore, the latching lever is self-engaging, which means more comfort for the user. For this concept, another LEGO model was created as a proof of concept.
Schofield model proof of concept, version 1
Initial concept drawing of Schofield
Prepacked coffee info
When critically evaluating the functionality of the designed mechanism, it was realized that a secondary lever to flip the coffee pod upwards would make the design overcomplicated. Instead, a removable holder for the coffee disc was thought up to replace the secondary lever. The LEGO model has also been modified to match this change.