US3668968A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Expansion fastener
Assignee: Individual
•
Filing: 1970-04-14
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Granted: 1972-06-13
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Expires: 1990-04-14
Abstract
Abstract The fastener has a spirally wound anchor sleeve which is circumferentially expanded within its mounting hole by inserting into the sleeve an anchor bolt or screw having a cross-section larger than the initial internal peripheral outline of the sleeve thereby locking the sleeve to the surrounding wall material. Initial grip of the sleeve in the mounting hole is provided and locking is further strengthened by providing on the outside of the sleeve teeth which bite into the wall material when the sleeve is inserted and expanded.
Inventors
- 👤 Henry J Modrey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:48
CPC Classifications
F; F16; F16B; F16B13/00; F16B13/12; F16B13/122; F16B13/02; F16B13/025
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
343 words
An expansion fastener for mounting in a mounting hole of a support member, said fastener comprising: an elongate anchor sleeve formed of a spirally wound strip made of springy material, the outer end of said strip extending outwardly from the outer peripheral wall of the sleeve substantially tangentially thereto and in opposition to the winding direction of the strip, the edge of said outer strip end being toothed, said toothed edge including portions disposed in axially and circumferentially staggered relationship on said peripheral outer wall, the inner end of said strip having substantially across the width thereof a radially inwardly protruding portion defining a lengthwise row of incomplete screw threads on the inner sleeve wall, said row of threads being upwardly slanted with reference to the center axis of the sleeve from one sleeve end toward the other, said one end of the sleeve being the leading end thereof and the other the trailing end, said leading end of the sleeve being inwardly tapered to facilitate insertion of the sleeve into the mounting hole; and an anchor bolt having a spirally threaded shank, the outer circumference of the threads on the shank gradually increasing from the tip of the shank toward the other end thereof, the maximal outer circumference of said shank threads being larger than the circumference defined by the incomplete threads at the trailing end of the sleeve, whereby upon insertion of the leading sleeve end into the mounting hole and threading of the bolt shank into the sleeve from the trailing end thereof the resulting outwardly directed radial pressure by the shank threads against the incomplete threads causes a substantially uniform circumferential expansion of the sleeve along the entire length thereof, said circumferential expansion of the sleeve causing pressure engagement of the toothed edge on the outside of the sleeve with the wall of the mounting hole thus locking the sleeve in a rotationally fixed position in the hole, and the coaction of the incomplete threads and the shank threads preventing axial displacement of the bolt relative to the sleeve.
Claim 2
Dependent Claim
343 words
An expansion fastener for mounting in a mounting hole of a support member, said fastener comprising: an elongate anchor sleeve formed of a spirally wound strip made of springy material, the outer end of said strip extending outwardly from the outer peripheral wall of the sleeve substantially tangentially thereto and in opposition to the winding direction of the strip, the edge of said outer strip end being toothed, said toothed edge including portions disposed in axially and circumferentially staggered relationship on said peripheral outer wall, the inner end of said strip having substantially across the width thereof a radially inwardly protruding portion defining a lengthwise row of incomplete screw threads on the inner sleeve wall, said row of threads being upwardly slanted with reference to the center axis of the sleeve from one sleeve end toward the other, said one end of the sleeve being the leading end thereof and the other the trailing end, said leading end of the sleeve being inwardly tapered to facilitate insertion of the sleeve into the mounting hole; and an anchor bolt having a spirally threaded shank, the outer circumference of the threads on the shank gradually increasing from the tip of the shank toward the other end thereof, the maximal outer circumference of said shank threads being larger than the circumference defined by the incomplete threads at the trailing end of the sleeve, whereby upon insertion of the leading sleeve end into the mounting hole and threading of the bolt shank into the sleeve from the trailing end thereof the resulting outwardly directed radial pressure by the shank threads against the incomplete threads causes a substantially uniform circumferential expansion of the sleeve along the entire length thereof, said circumferential expansion of the sleeve causing pressure engagement of the toothed edge on the outside of the sleeve with the wall of the mounting hole thus locking the sleeve in a rotationally fixed position in the hole, and the coaction of the incomplete threads and the shank threads preventing axial displacement of the bolt relative to the sleeve.
Claim 3
Dependent Claim
31 words
The expansion fastener according to claim 1 wherein the direction of the spiral winding of the sleeve and the hand of the screw thread on the bolt shank are in opposition.
Claim 4
Dependent Claim
44 words
The expansion fastener according to claim 1 wherein said inwardly protruding portion at the inner end of the strip is an inwardly bent strip portion toothed at its free edge, said toothed edge constituting said incomplete threads on the inner wall of the sleeve.
Claim 5
Dependent Claim
62 words
The expansion fastener according to claim 1 wherein said inwardly protruding portion comprises an axially elongate portion of the strip defining part of the inner wall of the sleeve and raised with reference to the underlying strip material, said raised strip portion including slots slanted with reference to the sleeve axis, said slots defining said incomplete threads on the inner sleeve wall.
Claim 6
Dependent Claim
76 words
The expansion fastener according to claim 1 and comprising means on the anchor sleeve adjacent to the trailing end thereof for rewinding the sleeve from its circumferentially expanded configuration to substantially its non-expanded configuration for withdrawing the sleeve from the mounting hole after removal of the bolt from the sleeve, said means comprising an outwardly extending peripheral flange at the trailing end of the sleeve, said flange including a cut-out for insertion of a rewinding tool.
Claim 7
Dependent Claim
33 words
The expansion fastener according to claim 1 wherein said outwardly extending outer strip end terminates in a stepped edge defining steps extending lengthwise of the sleeve, the edges of said steps being toothed.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |