How the First Coin-Operated Parking Meter Works
Carl Magee's 1935 invention of the mechanical parking meter, which introduced the concept of paying for temporary street parking using a coin-activated timer.
Original patent title: “Coin controlled parking meter”
Carl Magee's 1935 invention of the mechanical parking meter, which introduced the concept of paying for temporary street parking using a coin-activated timer. Granted to DUAL PARKING METER Co in 1938 with 15 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
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.
The gap
What does this patent NOT cover?
- 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.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The innovation was not just the timer, but the integration of a coin-actuated trigger that forced the user to perform a physical action to initiate a time-limited state, solving the problem of 'parking hogs' in downtown areas.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Original mechanical parking meters in Oklahoma City
Vintage coin-operated parking meters found in historical districts
Why it matters
The bigger picture
This patent effectively created the modern urban parking industry. By turning curb space into a revenue-generating asset, it allowed cities to manage traffic flow and turnover in busy commercial districts, fundamentally changing how city streets are organized.
Filed
May 13, 1935
Granted
May 24, 1938
Market context
Who's building on this
Companies in this space
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.
Market impact
This patent triggered the rapid adoption of metered parking across the United States, creating a new municipal revenue stream and a standard method for managing urban traffic congestion that persisted for over 70 years.
Claim 1 — Plain English
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.
The clever bit
The innovation was not just the timer, but the integration of a coin-actuated trigger that forced the user to perform a physical action to initiate a time-limited state, solving the problem of 'parking hogs' in downtown areas.
What it does not cover
- 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.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Early stage
Citation count
24/40
Moderately cited
Claim breadth
0/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$7K – $23K
Midpoint $14K · expired or expiring · industry ×1.5
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Concepts involved
Citations
Patent lineage
Cite this patent
Magee, C. C. (1938). How the First Coin-Operated Parking Meter Works (U.S. Patent No. 2,118,318). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/2118318/parking-meter-magee
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does How the First Coin-Operated Parking Meter Works cover?
Carl Magee's 1935 invention of the mechanical parking meter, which introduced the concept of paying for temporary street parking using a coin-activated timer.
Who owns patent US 2118318?
DUAL PARKING METER Co owns this patent, granted in 1938.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 2118318 cited by?
This patent has been cited by 15 later patents that build on its ideas.
What problem does this patent solve?
This patent effectively created the modern urban parking industry. By turning curb space into a revenue-generating asset, it allowed cities to manage traffic flow and turnover in busy commercial districts, fundamentally changing how city streets are organized.
What does this patent NOT cover?
Does not cover electronic or digital payment systems like credit card readers or mobile apps.
Patent monitoring