How A.C. Gilbert Designed Early Interlocking Toy Construction Blocks

A 1913 patent by A.C. Gilbert for a system of toy building blocks designed to snap together to create structures.

What it covers

This patent describes a mechanical system for toy construction blocks that feature specific interlocking mechanisms. The design allows individual blocks to be joined together securely to form larger, stable structures. By utilizing specific protrusions and corresponding recesses on the surfaces of the blocks, the system enables children to build models that hold their shape during play.

What it doesn't cover

• —Does not cover modern plastic bricks that use friction-fit studs like LEGO
• —Does not cover electronic or motorized construction sets
• —Does not cover non-interlocking stacking blocks like wooden cubes

The clever bit

The innovation lies in the specific geometry of the connectors, which aimed to balance ease of assembly for a child with enough structural integrity to keep the model from falling apart.

Why it matters

Alfred C. Gilbert was a major figure in the American toy industry, best known for his Erector Sets. This patent represents an early attempt to standardize how children could physically assemble toys, moving beyond simple stacking toward modular, structural engineering play.

Real-world examples

• 1.Early 20th-century wooden construction block sets
• 2.Mysto Manufacturing toy kits