How Walter Hunt Invented the Modern Safety Pin
Walter Hunt's 1849 patent for a simple, coiled wire device that keeps sharp points covered while fastening fabric.
Original patent title: “Walter hunt”
Walter Hunt's 1849 patent for a simple, coiled wire device that keeps sharp points covered while fastening fabric. Granted to Walter Hunt in 1849 with 4 forward citations.
Key facts
Coverage
What does this patent actually cover?
The device consists of a single piece of wire bent into a spring-like coil at one end. This coil provides the tension necessary to keep the pin closed. The other end features a protective sheath or guard that covers the sharp point of the pin when it is snapped into place. This mechanism allows the pin to pierce fabric and remain securely fastened without pricking the user.
The gap
What does this patent NOT cover?
- Does not cover straight pins lacking a protective clasp mechanism.
- Does not cover buttons, zippers, or other types of mechanical fasteners.
- Does not cover the use of multiple materials, as the patent specifically details a single continuous wire structure.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
By using the inherent tension of a coiled wire, Hunt created a self-closing mechanism that acts as both the hinge and the spring, eliminating the need for complex multi-part assemblies.
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 safety pins used in sewing kits
Diaper pins
Temporary clothing repairs
Why it matters
The bigger picture
This invention replaced dangerous, primitive straight pins that easily fell out or caused injury. It became a universal household staple for garment repair and textile manufacturing, demonstrating how a simple mechanical improvement can achieve global utility.
Granted
April 10, 1849
Market context
Who's building on this
Companies in this space
The basic design is now in the public domainpublic domainThe status of an invention no longer protected by any IP rights — anyone can use it freely. Patents enter the public domain after expiration.Read more →, meaning manufacturers globally produce variations of this pin. It remains a foundational design for simple, low-cost mechanical fastening.
Market impact
The invention standardized a safe, reliable method for fastening fabric, effectively creating a new category of consumer hardware that has remained largely unchanged for over 170 years.
Claim 1 — Plain English
What this patent covers
The device consists of a single piece of wire bent into a spring-like coil at one end. This coil provides the tension necessary to keep the pin closed. The other end features a protective sheath or guard that covers the sharp point of the pin when it is snapped into place. This mechanism allows the pin to pierce fabric and remain securely fastened without pricking the user.
The clever bit
By using the inherent tension of a coiled wire, Hunt created a self-closing mechanism that acts as both the hinge and the spring, eliminating the need for complex multi-part assemblies.
What it does not cover
- Does not cover straight pins lacking a protective clasp mechanism.
- Does not cover buttons, zippers, or other types of mechanical fasteners.
- Does not cover the use of multiple materials, as the patent specifically details a single continuous wire structure.
PatentBrief Score
Impact Score
Limited data
Citation count
14/40
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
$5K – $15K
Midpoint $10K · expired or expiring · industry ×1.6
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
(1849). How Walter Hunt Invented the Modern Safety Pin (U.S. Patent No. 6,281). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/6281/safety-pin-hunt
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 Walter Hunt Invented the Modern Safety Pin cover?
Walter Hunt's 1849 patent for a simple, coiled wire device that keeps sharp points covered while fastening fabric.
Who owns patent US 6281?
Walter Hunt owns this patent, granted in 1849.
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 6281 cited by?
This patent has been cited by 4 later patents that build on its ideas.
What problem does this patent solve?
This invention replaced dangerous, primitive straight pins that easily fell out or caused injury. It became a universal household staple for garment repair and textile manufacturing, demonstrating how a simple mechanical improvement can achieve global utility.
What does this patent NOT cover?
Does not cover straight pins lacking a protective clasp mechanism.
Patent monitoring