How the First Automatic Pop-Up Toaster Works
Charles Strite's 1921 patent for the first toaster that automatically pops bread up after a set time, preventing it from burning.
Original patent title: “Bread-toaster”
Charles Strite's 1921 patent for the first toaster that automatically pops bread up after a set time, preventing it from burning. Granted to Individual in 1921 with 2 forward citations, and it is now in the public domain.
Coverage
What does this patent actually cover?
The patent describes a mechanical toaster featuring a timer mechanism that controls the heating duration and a spring-loaded carriage. Once the timer expires, it triggers a release mechanism that allows the spring to push the bread carriage upward, effectively removing the toast from the heating elements. This design ensures the bread is toasted to a specific degree without requiring manual monitoring or intervention.
The gap
What does this patent NOT cover?
- Does not cover electronic sensors that detect the color or moisture level of the bread.
- Does not cover toasters that use conveyor belts for continuous toasting.
- Does not cover induction-based heating methods.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
Key facts
What made this novel
The innovation lies in integrating a mechanical timer with a spring-loaded release, solving the problem of burnt toast by decoupling the heating process from human presence.
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
Standard household pop-up toasters
Commercial bread toasting equipment
Why it matters
The bigger picture
This invention fundamentally changed breakfast habits by moving bread toasting from a manual, attention-heavy task to an automated one. It established the standard 'pop-up' interaction model used in nearly every household toaster today.
Filed
June 22, 1920
Granted
October 18, 1921
Market context
Who's building on this
Companies in this space
Major appliance manufacturers like Sunbeam, Breville, and KitchenAid continue to refine the basic mechanical pop-up architecture established by Strite.
Market impact
This patent enabled the creation of the modern home appliance market for breakfast toasting. It shifted consumer expectations toward convenience and automation, effectively replacing manual toasting forks and open-flame methods.
Claim 1 — Plain English
What this patent covers
The patent describes a mechanical toaster featuring a timer mechanism that controls the heating duration and a spring-loaded carriage. Once the timer expires, it triggers a release mechanism that allows the spring to push the bread carriage upward, effectively removing the toast from the heating elements. This design ensures the bread is toasted to a specific degree without requiring manual monitoring or intervention.
The clever bit
The innovation lies in integrating a mechanical timer with a spring-loaded release, solving the problem of burnt toast by decoupling the heating process from human presence.
What it does not cover
- Does not cover electronic sensors that detect the color or moisture level of the bread.
- Does not cover toasters that use conveyor belts for continuous toasting.
- Does not cover induction-based heating methods.
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
Patent enters public domain
This patent is in the public domain
See the Freedom to Build guide — what is free to use, what is not, and how to cite this patent.
PatentBrief Score
Impact Score
Limited data
Citation count
10/40
Early citations
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 – $21K
Midpoint $13K · expired or expiring · industry ×2.2
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Claim text not yet imported for this patent
Concepts involved
Citations
Patent lineage
Cite this patent
Strite, C. P. (1921). How the First Automatic Pop-Up Toaster Works (U.S. Patent No. 1,394,450). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/1394450/pop-up-toaster-strite
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 Automatic Pop-Up Toaster Works cover?
Charles Strite's 1921 patent for the first toaster that automatically pops bread up after a set time, preventing it from burning.
Who owns patent US 1394450?
Individual owns this patent, granted in 1921.
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 1394450 cited by?
This patent has been cited by 2 later patents that build on its ideas.
What problem does this patent solve?
This invention fundamentally changed breakfast habits by moving bread toasting from a manual, attention-heavy task to an automated one. It established the standard 'pop-up' interaction model used in nearly every household toaster today.
What does this patent NOT cover?
Does not cover electronic sensors that detect the color or moisture level of the bread.
Same assignee
More from Individual
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