US4054045A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-piece mandrel assembly for deforming
Assignee: Individual
•
Filing: 1976-04-05
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Granted: 1977-10-18
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Expires: 1996-04-05
Abstract
Abstract A hole expansion mandrel assembly for expanding holes through work pieces including a drive pin with a leading pulling section and a trailing driving shoulder; and a collet removably carried on the drive pin and abutting the driving shoulder where the collet has an expansion surface to enlarge the holes as the drive pin is used to force the collet through the holes. The drive pin may incorporate a fastener trailing the collet. The method of using the apparatus is also contemplated.
Inventors
- 👤 John O. King, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:49
CPC Classifications
B; B23; B23P; B23P9/00; B23P9/02; B23P9/025; B21; B21J; B21J15/00; B21J15/02; B21J15/022; F; F16; F16B; F16B19/00; F16B19/04; F16B19/05; F16B4/00; F16B4/004; Y; Y10; Y10S; Y10S411/00; Y10S411/955; Y10S411/965; Y10S411/968; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49861; Y10T29/49885; Y10T29/49972
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
310 words
A hole expansion mandrel assembly for use in expanding a pilot hole with a prescribed hole diameter through a work piece comprising: an elongate drive pin having a support central axis, and including a pulling section adjacent the leading end of said drive pin and an annular driving shoulder rearwardly of said pulling section, said pulling section having a first outside diameter a prescribed amount smaller than the hole diameter and said shoulder defining an annular driving face on that side facing the leading end of said drive pin having a second outside diameter a second prescribed amount larger than said first outside diameter; and, a seamless annular expansion collet defining a central passage therethrough about a collet central axis and an outside expansion surface about said collet central axis that tapers outwardly from the leading end of said collet, said central passage having a third inside diameter at least as large as said first diameter of said pulling section and smaller than said second outside diameter of said driving face, said expansion surface having a fourth minor outside diameter smaller than the hole diameter and a fifth major outside diameter larger than said second outside diameter of said driving face and larger than the hole diameter by a fifth prescribed amount, said collet further defining an annular abutting surface on the trailing end thereof, said collet slidably received over said pulling section with said abutting surface engaged by said driving face of said shoulder so that said pulling section can be inserted through the hole, leading end, first, until said expansion surface on said collet engages one side of the work piece about the hole and the pulling section can be gripped from the opposite side of the work piece to force the collet through the hole without significantly changing the size of said collet to expand the hole.
Claim 2
Dependent Claim
310 words
A hole expansion mandrel assembly for use in expanding a pilot hole with a prescribed hole diameter through a work piece comprising: an elongate drive pin having a support central axis, and including a pulling section adjacent the leading end of said drive pin and an annular driving shoulder rearwardly of said pulling section, said pulling section having a first outside diameter a prescribed amount smaller than the hole diameter and said shoulder defining an annular driving face on that side facing the leading end of said drive pin having a second outside diameter a second prescribed amount larger than said first outside diameter; and, a seamless annular expansion collet defining a central passage therethrough about a collet central axis and an outside expansion surface about said collet central axis that tapers outwardly from the leading end of said collet, said central passage having a third inside diameter at least as large as said first diameter of said pulling section and smaller than said second outside diameter of said driving face, said expansion surface having a fourth minor outside diameter smaller than the hole diameter and a fifth major outside diameter larger than said second outside diameter of said driving face and larger than the hole diameter by a fifth prescribed amount, said collet further defining an annular abutting surface on the trailing end thereof, said collet slidably received over said pulling section with said abutting surface engaged by said driving face of said shoulder so that said pulling section can be inserted through the hole, leading end, first, until said expansion surface on said collet engages one side of the work piece about the hole and the pulling section can be gripped from the opposite side of the work piece to force the collet through the hole without significantly changing the size of said collet to expand the hole.
Claim 3
Dependent Claim
54 words
The hole expansion mandrel assembly of claim 1 wherein said drive pin further includes a support section between said pulling section and said driving shoulder, said support section defining a support surface therearound sized to engage said collet about said central passage so that said collet is in bearing support on said support section.
Claim 4
Dependent Claim
71 words
The hole expansion mandrel assembly of claim 2 wherein said drive pin further includes a breakneck section connecting said driving shoulder with said support section and defining a reduced diameter breakneck groove therein constructed and arranged to fracture at said breakneck groove to separate said driving shoulder from the rest of said drive pin upon application of a force in excess of a prescribed amount being applied to said drive pin.
Claim 5
Dependent Claim
46 words
The mandrel assembly of claim 3 wherein said fifth major outside diameter is located in a plane normal to said support central axis and located forwardly of the trailing end of said support section on said drive pin when said driving face engages said abuttment surface.
Claim 6
Dependent Claim
60 words
The mandrel assembly of claim 4 wherein said drive pin further includes a fastener having a leading engagement section to be engaged to lock said fastener in place, a bearing section connected to the trailing end of said engagement section and a head connected to the trailing end of said bearing section, said engagement section integral with said driving shoulder.
Claim 7
Dependent Claim
15 words
The mandrel assembly of claim 5 wherein said engagement section defines nut receiving threads thereon.
Claim 8
Dependent Claim
15 words
The mandrel assembly of claim 5 wherein said engagement section defines lockbolt locking grooves therein.
Claim 9
Dependent Claim
78 words
The mandrel assembly of claim 2 wherein said drive pin further includes a driving extension rearwardly of said driving shoulder, said driving extension defining a driven face on the rear end thereof oriented perpendicular to the support central axis; said assembly further including a driver adapted to drivingly engage said driven face to exert a force on said drive pin toward the leading end thereof; and locating means for maintaining alignment between said driven face and said driver.
Claim 10
Dependent Claim
36 words
The hole expansion mandrel assembly of claim 2 wherein said drive pin further includes connection means releasably connecting said driving shoulder with said support section so that said driving shoulder is coaxial with said support section.
Claim 11
Dependent Claim
36 words
The hole expansion mandrel assembly of claim 6 wherein said drive pin further includes connection means releasably connecting said driving shoulder with said support section so that said driving shoulder is coaxial with said support section.
Claim 12
Dependent Claim
58 words
The hole expansion mandrel assembly of claim 6 wherein said abutting surface on said collet has a sixth prescribed outside diameter at least as small as the root diameter of said threads, said collet further defining a clearance surface extending outwardly from and forwardly of said abutment surface to prevent damage to said threads on said engagement section.
Claim 13
Dependent Claim
91 words
The hole expansion mandrel assembly of claim 1 wherein said expansion surface on said collet has a first average expansion slope and wherein said collet further defines a contraction surface thereon trailing said expansion surface and tapering inwardlly toward the trailing end of said collet from said fifth major outside diameter of said expansion surface to a seventh trailing minor diameter smaller than the recovered diameter of the holes after passage of said collet therethrough, said contraction surface having a second average contraction slope less than said first average expansion slope.
Claim 14
Dependent Claim
32 words
The hole expansion mandrel assembly of claim 12 wherein said expansion surface has a first surface area and said contraction surface has a second surface area larger than said first surface area.
Claim 15
Dependent Claim
30 words
The hole expansion mandrel assembly of claim 1 wherein said expansion surface is convex with a decreasing slope from its leading end toward its trailing end of increasing mechanical advantage.
Claim 16
Dependent Claim
16 words
The hole expansion mandrel assembly of claim 14 wherein said expansion surface is semi-ellipsoidal in shape.
Claim 17
Dependent Claim
55 words
The hole expansion mandrel assembly of claim 1 further including a compressible cleaning member mounted on said drive pin forward of said collet, said cleaning member having an eighth outside uncompressed diameter larger than the hole diameter so that said cleaning member leads said collet through the hole and cleans the inside of said hole.
Claim 18
Dependent Claim
33 words
The hole expansion mandrel assembly of claim 16 wherein said cleaning member includes a lubricant, said cleaning member expelling the lubricant onto the hole surface as said cleaning member passes through the hole.
Claim 19
Dependent Claim
23 words
The hole expansion mandrel assembly of claim 17 wherein said cleaning member is removably mounted on the leading end of said pulling section.
Claim 20
Dependent Claim
51 words
The mandrel assembly of claim 1 wherein said drive pin further includes a fastener integral with and trailing said driving shoulder, said fastener including a bearing section for passage into said pilot hole after expansion by said expansion collet and an enlarged head on the trailing end of said bearing section.
Claim 21
Dependent Claim
60 words
The mandrel assembly of claim 1 wherein said drive pin further includes a fastener having a leading engagement section to be engaged to lock said fastener in place, a bearing section connected to the trailing end of said engagement section and a head connected to the trailing end of said bearing section, said engagement section integral with said driving shoulder.
Claim 22
Dependent Claim
15 words
The mandrel assembly of claim 20 wherein said engagement section defines nut receiving threads thereon.
Claim 23
Dependent Claim
58 words
The hole expansion mandrel assembly of claim 21 wherein said abutting surface on said collet has a sixth prescribed outside diameter at least as small as the root diameter of said threads, said collet further defining a clearance surface extending outwardly from and forwardly of said abuttment surface to prevent damage to said threads on said engagement section.
Claim 24
Dependent Claim
36 words
The hole expansion mandrel assembly of claim 22 wherein said drive pin further includes connection means releasably connecting said driving shoulder with said support section so that said driving shoulder is coaxial with said support section.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-17 | 1981-04-18 | 1981-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-17 | 1985-04-18 | 1985-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-17 | 1989-04-18 | 1989-10-18 | $7700.00 | Window Closed / Lapsed |