US3711049A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mechanical load limiter for power lines
Assignee: PACIFIC UTILITIES SUPPLY Co
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Filing: 1971-12-09
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Granted: 1973-01-16
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Expires: 1991-12-09
Abstract
Abstract A limiter is fixed at one end to a power line tower, or pole arm, and at the other to an insulator attached to a power line. Movement of the line beyond a predetermined limit in either direction causes the limiter to release the insulator, dropping the line and preventing damage to the tower. In one modification, angular movement of the insulator upsets a toggle held in position by a latch in such manner that a cam surface attached to the insulator lifts the latch as the insulator pivots beyond a predetermined angle. The cam shape determines the angle which causes unlatching. In another modification, the horizontal component of the force on the tower is resisted by a springloaded lever system; and when the force exceeds a predetermined amount, the spring releases the lever system and the insulator is released.
Inventors
- 👤 R Grannis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:56
CPC Classifications
H; H02; H02G; H02G7/00; H02G7/05
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
176 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower, said first member comprising a casing and a link pivotally mounted on said casing about a first axis and having a support position and a release position, a second member having second means for suspending the upper end of an insulator string from said device, said second member movable relative to said first member with a horizontal component having a magnitude proportional to the horizontal load on a conductor attached to the lower end of said insulator string, third means normally holding said link in support position, said second member being supported from said first member, said second member being articulately connected to said link for relative pivotal movement about a second axis parallel to said first axis and vertically displaced therefrom, increase in magnitude of the horizontal load on said second member biasing said link toward release position to render said third means inoperative and to drop said insulator string from said pole or tower.
Claim 2
Dependent Claim
176 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower, said first member comprising a casing and a link pivotally mounted on said casing about a first axis and having a support position and a release position, a second member having second means for suspending the upper end of an insulator string from said device, said second member movable relative to said first member with a horizontal component having a magnitude proportional to the horizontal load on a conductor attached to the lower end of said insulator string, third means normally holding said link in support position, said second member being supported from said first member, said second member being articulately connected to said link for relative pivotal movement about a second axis parallel to said first axis and vertically displaced therefrom, increase in magnitude of the horizontal load on said second member biasing said link toward release position to render said third means inoperative and to drop said insulator string from said pole or tower.
Claim 3
Dependent Claim
124 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower, a second member having second means for suspending the upper end of an insulator string from said device, a link pivotally attached to said first member, a latch for latching said link in support position relative to said first member, third means for suspending said second member from said link when said link is in support position and releasing said second member when said link is pivoted out oF support position, and cooperating fourth means on said second member and said latch for unlatching said link from support position when the angle between said second member and said first member exceeds a pre-selected amplitude.
Claim 4
Dependent Claim
124 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower, a second member having second means for suspending the upper end of an insulator string from said device, a link pivotally attached to said first member, a latch for latching said link in support position relative to said first member, third means for suspending said second member from said link when said link is in support position and releasing said second member when said link is pivoted out oF support position, and cooperating fourth means on said second member and said latch for unlatching said link from support position when the angle between said second member and said first member exceeds a pre-selected amplitude.
Claim 5
Dependent Claim
46 words
A device according to claim 2 in which the upper end of said link is formed with a notch, said third means comprising a stud fitting into the bottom of said notch, said latch also fitting into said notch when said link is in support position.
Claim 6
Dependent Claim
29 words
A device according to claim 3 in which the pivot for said link, said stud and said latch are in vertical alignment when said link is in support position.
Claim 7
Dependent Claim
65 words
A device according to claim 4 in which the upper edge of said second member is formed with a cam surface and said latch with a cam-engaging surface engaging said cam surface when said second member pivots relative to said link through a restricted amplitude, said cam surface having latch lifting surfaces at either end lifting said cam-engaging surface when said preselected amplitude is exceeded.
Claim 8
Dependent Claim
140 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower and having a support for supporting the upper end of an insulator string, said support having a limited length in a horizontal direction, a link pivotted to said first member having an upright position, second means adapted to be attached to an insulator for pivoting said link responsive to horizontal movement of said string, and resilient third means biasing said link toward upright position, said link when in upright position maintaining said second means supported by said support, said second means having two release positions at opposite ends of said support, said link when in either of said release positions being unsupported by said support to permit said second means to move off said support to drop from said support.
Claim 9
Dependent Claim
140 words
A load limiting device comprising a first member having first means for suspending said device from a pole or tower and having a support for supporting the upper end of an insulator string, said support having a limited length in a horizontal direction, a link pivotted to said first member having an upright position, second means adapted to be attached to an insulator for pivoting said link responsive to horizontal movement of said string, and resilient third means biasing said link toward upright position, said link when in upright position maintaining said second means supported by said support, said second means having two release positions at opposite ends of said support, said link when in either of said release positions being unsupported by said support to permit said second means to move off said support to drop from said support.
Claim 10
Dependent Claim
54 words
A device according to claim 6 in which said third means comprises a pair of levers on opposite sides of said link and a spring interconnecting said levers to bias both said levers toward said link, said spring yielding responsive to force of said second means in a horizontal component relative to said link.
Claim 11
Dependent Claim
42 words
A device according to claim 6 in which said support comprises a horizontal ledge, said second means comprising a pin sliding on said ledge and supported by said ledge for the length of said limited length and then dropping from said ledge.
Claim 12
Dependent Claim
69 words
A device according to claim 6 in which said first member has a downward extension, said support formed on the lower end of said downward extension, said link pivoted to said downward extension and having a notch on its bottom edge, movable in proximity to said support, said second means comprising a pin fitting into said notch and resting on said support when said link is in upright position.
Claim 13
Dependent Claim
63 words
A device according to claim 9 in which said link has an upwardly extending ear, said third means comprising a pair of bell cranks pivoted to said first member each having an arm engaging said ear when said link is in upright position, and a spring interconnecting said cranks and biasing said arms toward each other with said ear interposed between said arms.
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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) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |