Not only can you see them, you can hear them as well. Many times very useful inventions are composed of simple parts and configurations. Such as this Torsionally Elastic Assembly for Driving a Centrifuge Rotor. If you are always thinking of simple little improvements, remember, if you don't patent it somebody else will. Some patents protect big and powerful machinery.
Some patents protect bigger and more powerful machinery.
While many other patents are issued for very tiny inventions. The novel feature in this drawing is found in reference number 2. Not all patents are mechanical or high technology devices. This inventor employs high technology to create this award plaque. It is comprised of a transparent material and a stone surface material, laser-cut to a conforming geometrical configuration.