You can freely build on How Mary Anderson Invented the Windshield Wiper

What this patent covers

The device consists of a swinging arm with a rubber blade attached to a lever inside the car. When the driver moves the lever, the arm pivots across the glass to clear away moisture or debris. It was designed to improve visibility during bad weather without requiring the driver to stop the car and exit to clean the windshield manually.

What is now free to use

All 0 claims of US 743801 are in the public domain. Specifically:

The 0 dependent claims add narrowing limitations and are also free.

What is NOT covered

Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.

• Does not cover automatic or motorized wiper systems.

• Does not cover sensors that detect rain to trigger wiping.

• Does not cover intermittent or variable speed control mechanisms.

Who is building on this today

While the original patent has long expired, every major automotive manufacturer like Ford, Toyota, and Volkswagen builds on the fundamental concept of windshield clearing systems. Modern suppliers like Bosch and Denso continue to iterate on the efficiency and automation of these systems.

Products built on expired version of this technology

How to cite this patent in your documentation

Individual. US Patent 743801. Window-cleaning device.. Granted 1903, expired 1923. Now in the public domain.

Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.

PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.