• All sections
• G - Physics
• G09B - Educational or demonstration appliances; appliances for teaching, or communicating with, the blind, deaf or mute; models; planetaria; globes; maps; diagrams
• G09B 3/04 - Manually- or mechanically-operated teaching appliances working with questions and answers of the type wherein the student is expected to construct an answer to the question which is presented or wherein the machine gives an answer to the question presented by the student of chart form

Patent holdings for IPC class G09B 3/04

Total number of patents in this class: 2

10-year publication summary

Principal owners for this class