How should improvements on existing inventions be illustrated in patent drawings?

When illustrating improvements on existing inventions, patent drawings should follow specific guidelines as outlined in MPEP 608.02(d):

1. Show the improved portion disconnected from the old structure
2. In a separate view, show only enough of the old structure to demonstrate the connection with the improvement

The MPEP cites 37 CFR 1.83(b): When the invention consists of an improvement on an old machine the drawing must when possible exhibit, in one or more views, the improved portion itself, disconnected from the old structure, and also in another view, so much only of the old structure as will suffice to show the connection of the invention therewith. This approach helps to clearly distinguish the new, improved elements from the existing technology.

To learn more:

• patent drawings
• improvement inventions
• existing technology
• illustration guidelines