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US 2118318Freedom to Build
Public domain since 1955

You can freely build on How the First Coin-Operated Parking Meter Works

This patent expired in 1955. 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

DUAL PARKING METER Co

Patent granted

1938

Expired

1955

Forward citations

15

What this patent covers

The device functions as a mechanical timer housed in a weather-resistant casing. When a user inserts a coin, it engages a gear mechanism that physically rotates a dial or pointer to show the remaining time. As time passes, the internal clockwork mechanism slowly moves the pointer back to zero, at which point the parking time expires. This provided a way for cities to regulate curb space by physically limiting how long a vehicle could occupy a specific spot.

What is now free to use

All 0 claims of US 2118318 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 electronic or digital payment systems like credit card readers or mobile apps.

    • Does not cover networked systems that communicate with a central server to track occupancy.

    • Does not cover sensors that detect the presence of a vehicle to start or stop the timer automatically.

    Who is building on this today

    While the original Dual Parking Meter Company is no longer the dominant player, modern companies like IPS Group and Flowbird have built on this legacy by integrating cloud connectivity and digital payments into the physical parking meter infrastructure.

    Products built on expired version of this technology

    Original mechanical parking meters in Oklahoma City

    Vintage coin-operated parking meters found in historical districts

    How to cite this patent in your documentation

    DUAL PARKING METER Co. US Patent 2118318. Coin controlled parking meter. Granted 1938, expired 1955. 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.

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