You can freely build on Ralph Teetor's Speed Control Device for Automobiles
This patent expired in 1968. Every claim — 0 independent, 0 dependent — is now unenforceable. Anyone can use, reproduce, manufacture, sell, or offer for sale this technology without a license.
Original assignee
Individual
Patent granted
1950
Expired
1968
Forward citations
23
What this patent covers
The device acts as a mechanical governor for an automobile's accelerator pedal. It uses a speed-sensing mechanism connected to the vehicle's drivetrain to monitor velocity. When the car reaches a pre-selected speed, the device engages a resistance mechanism that pushes back against the driver's foot on the gas pedal. This provides tactile feedback to the driver, effectively signaling or maintaining a constant speed by making it physically difficult to accelerate further without intentional effort.
What is now free to use
All 0 claims of US 2519859 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 fully electronic drive-by-wire throttle systems.
Does not cover automatic braking or collision avoidance systems.
Does not cover systems that maintain speed without providing physical feedback to the pedal.
Who is building on this today
Major automotive suppliers like Bosch and Continental have evolved these mechanical principles into sophisticated electronic cruise control and adaptive cruise control systems used by virtually every global automaker today.
Products built on expired version of this technology
Early mechanical cruise control systems in 1950s and 60s Chrysler vehicles
Speedostat systems
How to cite this patent in your documentation
Individual. US Patent 2519859. Speed control device for resisting operation of the accelerator. Granted 1950, expired 1968. 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.