US3658296A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for post-tensioning and anchoring prestressing tendons
Assignee: Individual
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Filing: 1970-09-24
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Granted: 1972-04-25
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Expires: 1990-09-24
Abstract
Abstract A system for applying tension to and anchoring the end of a prestressing tendon extending from a concrete structure. The system includes a jack for applying tension to the tendon at a first location along the length thereof, anchoring means comprising an anchoring plate and collar means disposed about the tendon and adapted for movement into cooperation with the anchoring plate to grip the tendon located at a point on the tendon between the first location and the concrete structure, and actuator means mounted for movement relative to the jack and the anchoring plate to position the collar means into engagement with the plate and into gripping engagement with the tendon. The actuator means and the collar means incorporate cooperable structure for retaining the collar means against movement relative to the actuator means until the collar means moves into said gripping engagement.
Inventors
- 👤 Lawrence R Yegge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:33
CPC Classifications
E; E04; E04C; E04C5/00; E04C5/08; E04C5/12; E04C5/122; E04G; E04G21/00; E04G21/12; E04G21/121; Y; Y10; Y10T; Y10T29/00; Y10T29/53; Y10T29/53796; Y10T29/5383
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
220 words
An assemblage for applying tension to and anchoring the end of a prestressing tendon extending from a concrete structure, said assemblage comprising: A. a jack having a base member disposed in compression imparting relationship to said structure and a ram selectively expansible relative to said base member disposed in gripping engagement with said tendon at a first location along the length of said tendon; B. anchoring means disposed about said tendon at a second location along the length thereof between said structure and said first location, said anchoring means comprising: a. an anchoring plate having a truncated conical hole through which the tendon is directed; and b. collar means disposed about said tendon and adapted for movement relative to said tendon from a first position wherein said collar means is out of engagement with said anchoring plate to a second position wherein said collar means is wedged into said anchor plate hole and grippingly engages said tendon; and C. actuator means mounted for movement relative to said base member for moving said collar means from said first position to said second position, said actuator means and said collar means incorporating cooperable structure for retaining said collar means against movement relative to said actuator means until the collar means reaches said second position whereupon said Actuator means releases said collar means.
Claim 2
Dependent Claim
220 words
An assemblage for applying tension to and anchoring the end of a prestressing tendon extending from a concrete structure, said assemblage comprising: A. a jack having a base member disposed in compression imparting relationship to said structure and a ram selectively expansible relative to said base member disposed in gripping engagement with said tendon at a first location along the length of said tendon; B. anchoring means disposed about said tendon at a second location along the length thereof between said structure and said first location, said anchoring means comprising: a. an anchoring plate having a truncated conical hole through which the tendon is directed; and b. collar means disposed about said tendon and adapted for movement relative to said tendon from a first position wherein said collar means is out of engagement with said anchoring plate to a second position wherein said collar means is wedged into said anchor plate hole and grippingly engages said tendon; and C. actuator means mounted for movement relative to said base member for moving said collar means from said first position to said second position, said actuator means and said collar means incorporating cooperable structure for retaining said collar means against movement relative to said actuator means until the collar means reaches said second position whereupon said Actuator means releases said collar means.
Claim 3
Dependent Claim
39 words
The assemblage of claim 1 wherein said collar means comprises a plurality of internally toothed wedge segments, said cooperable structure including biasing means cooperable with the wedge segments to continuously urge said wedge segments into engagement with said tendon.
Claim 4
Dependent Claim
73 words
The assemblage of claim 2 wherein said tendon comprises a plurality of strands, said anchoring plate having at least one truncated conical hole for each strand of said tendon, and a plurality of wedge segments are provided for each of said strands, said actuator means cooperable with said wedge segments to substantially simultaneously move all of the wedge segments provided for all of the strands from said first position to said second position.
Claim 5
Dependent Claim
66 words
The assemblage of claim 1 wherein said jack includes a housing within which said actuator means is slidably disposed and defining at least one longitudinal slot providing communication between the interior of said housing and the exterior thereof, said actuator means incorporating handle means projecting outwardly through said slot and adapted to be engaged by the operator to move said actuator means relative to the housing.
Claim 6
Dependent Claim
62 words
The assemblage of claim 1 wherein said collar means comprises a plurality of internally toothed wedge segments, said cooperable structure comprising: a recess formed in said actuator means; a reduced end portion formed on each of said wedge segments for reception in said recess; and a flexible element compressably disposed in said recess between said actuation means and said reduced end portions.
Claim 7
Dependent Claim
50 words
The assemblage of claim 5 wherein each of said reduced end portions has a groove formed in the outer surface thereof, said grooves being disposed in circumferential alignment about said tendon, said flexible element comprising an O-ring of resilient material disposed in said aligned grooves of said reduced end portions.
Claim 8
Dependent Claim
18 words
The assemblage of claim 6 wherein said actuator means includes means for securing said O-ring within said recess.
Claim 9
Dependent Claim
67 words
The assemblage of claim 7 wherein said securing means comprises a retention plate affixed to said actuator means and defining an aperture, said aperture overlying said actuator means recess and having a cross-sectional dimension less than the corresponding cross-sectional dimension of said recess whereby a portion of said retention plate is disposed over said recess and said O-ring is prevented thereby from moving out of said recess.
Claim 10
Dependent Claim
26 words
The assemblage of claim 8 wherein said actuator means has a throughbore formed therein in communication with said recess, said throughbore slidably receiving said tendon therein.
Claim 11
Dependent Claim
36 words
The assemblage of claim 8 wherein said wedge segments have shoulders formed thereon, said shoulders being in abutting engagement with said retention plate when said collar means is retained against movement relative to said actuation means.
Claim 12
Dependent Claim
105 words
The assemblage of claim 1 wherein said jack ram has affixed thereto a jack plate having a conical throughbore formed therein for receiving said tendon; an apertured auxiliary plate mounted on said jack plate for reciprocal movement relative thereto; means biasing said apertured plate into spaced relation relative to said jack plate with said aperture and said throughbore in substantial alignment; and a locking collar disposed about said tendon releasably retained within the aperture of said auxiliary plate, said collar upon movement of said auxiliary plate against the force exerted by said biasing means moving into said throughbore and into gripping engagement with said tendon.
Claim 13
Dependent Claim
137 words
Apparatus for establishing gripping engagement with a prestressing tendon extending from a concrete structure for the purpose of post-tensioning said structure, said apparatus comprising: a plate having a truncated conical hole formed therein for receiving said tendon; a collar slidably disposed about said tendon and including internally dispoSed teeth, a generally conical-shaped outer surface, said collar movable from a first position out of engagement with said plate to a second position wherein said collar is wedged into the plate hole with said conical-shaped outer surface in engagement with said plate and said collar grippingly engaging said tendon; and means releasably connected to said collar and mounted for slidable movement relative to said plate to move said collar from said first position to said second position, said means releasing said collar when said collar reaches said second position.
Claim 14
Dependent Claim
137 words
Apparatus for establishing gripping engagement with a prestressing tendon extending from a concrete structure for the purpose of post-tensioning said structure, said apparatus comprising: a plate having a truncated conical hole formed therein for receiving said tendon; a collar slidably disposed about said tendon and including internally dispoSed teeth, a generally conical-shaped outer surface, said collar movable from a first position out of engagement with said plate to a second position wherein said collar is wedged into the plate hole with said conical-shaped outer surface in engagement with said plate and said collar grippingly engaging said tendon; and means releasably connected to said collar and mounted for slidable movement relative to said plate to move said collar from said first position to said second position, said means releasing said collar when said collar reaches said second position.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-25 | 1975-10-25 | 1976-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-25 | 1979-10-25 | 1980-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-25 | 1983-10-25 | 1984-04-25 | $7700.00 | Window Closed / Lapsed |