Functions & Components

External Features

Below is a picture of one of the most popular single serve coffee makers on the market, the Keurig. The outside of this pod style coffee maker consists of four main components: (1) The water housing, (2) the lid, (3) controls, and the (4) drip tray.

1. Water Housing

The water housing stores water so that the user does not have to add water every time they make a cup of coffee. This housing varies in size for different coffee makers, but for the standard Keurig it holds 48 oz [1]. That is enough water to fill six cups of coffee.


2. Pod Housing

The pod housing is a complex mechanical system on the top of the machine that houses the pod (see 2.1 for pod details). When the silver handle on the lid is lifted, the housing tilts forward. This allows for a pod to fit into the cup holder. At the bottom of the cup holder and inside top of the pod housing is a sharp metal pin, that penetrates the top and bottom of the pod when the lid is closed.


2.1. Pod

A pod is a small plastic cup that holds a single serving size of coffee grounds. As seen in the picture above, there is a small paper filter in the pod, and then the grounds are held in the filter. The pod is sealed by an aluminum lid on top. As the single serve coffee making has taken off, several companies come out with their own pods, that come in a variety of flavors.

For more information on the pod, visit the link below.


3. Controls

The controls are the main electrical component of the coffee maker. The various lights, are different indications of the actions or requirements for the machine. The other blue buttons are controls for different amounts of coffee. This is also where you turn the coffee maker on, and set the “Auto Off” function. This “Auto Off” function is a key component for the pod style coffee makers efficiency. This keeps the coffee maker from being left on too long, and wasting electricity.


4. Drip Tray

The drip tray is a removable component on the bottom of the coffee maker. This is where a coffee cup is set in order to get filled up. It is also designed to store overflow, so that if a cup is overfilled, or the machine is turned on without a cup underneath it, there will not be a mess.

All above images source:


Internal Features

Rear view of the internal component parts of a Tassimo coffee maker

Image source:

In the above image, components 2-4 are the main internal features.

2. Water Heater – this component heats the water up so that the beverage is warm when consumed. It heats the water from 20 C to 85 C in under one minute [2].

3. Water Pump – the pump moves water from the holding tank to water heater.

4. Air Compressor – the air compressor forces pressurized water from the water heater into the pod so that the the water can flow through the pod filter into the cup.

For more information on the pod style coffee maker check out this link.


How it works!

Artwork showing how a pod coffee maker works

Image source:

Above is a diagram from Explain That Stuff [2] that shows the process of brewing coffee in a pod style coffee maker, assuming that a pod has already been inserted in the pod housing.

  1. Water is added to the water housing
  2. The water is pumped from the water housing into the heating element
  3. Heat the water and force it up to the pod housing
  4. Water is forced through a funnel, to increase the pressure, into the pod
  5. Coffee is brewed inside the pod
  6. The coffee is forced through the filter in the bottom of the pod and into the cup
  7. Finished cup of coffee
For video representation of how it works, check out this link.



[1] Keurig. (2020). [online] Available at: [Accessed 14 Feb. 2020].

[2] Woodford, C. (2020). Single-serve pod coffee makers | How they work. [online] Explain that Stuff. Available at: [Accessed 14 Feb. 2020].