US3710044A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Jackscrew type of racking mechanism for a movable switchgear unit
Assignee: General Electric Co
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Filing: 1971-12-23
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Granted: 1973-01-09
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Expires: 1991-12-23
Abstract
Abstract For racking a movable switchgear unit into and out of its enclosure, a racking mechanism is disclosed which comprises a jackscrew mounted on the movable switchgear unit, a traveling nut mounted on the jackscrew, and an anchoring device mounted on the enclosure having an opening receiving a lug on the traveling nut. A housing for the jackscrew contains a first slot extending axially of the jackscrew for holding the lug in said opening in the anchoring device during racking movement. The jackscrew housing also contains a second slot perpendicular to the first slot into which said lug can be moved when the nut is being uncoupled from the anchoring device. Friction means causes the nut to rotate with the jackscrew when the nut is properly positioned for uncoupling from the anchoring device, thereby causing jackscrew-rotation under these conditions to move the lug from the opening in the anchoring device into said second slot.
Inventors
- 👤 W Sharp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:02
CPC Classifications
H; H02; H02B; H02B11/00; H02B11/12; H02B11/127
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
374 words
Electric switchgear comprising an enclosure, a switchgear unit movable into and out of said enclosure, and racking mechanism for moving said switchgear unit into and out of a fully inserted contact engaging position within said enclosure, said racking mechanism comprising: a. a jackscrew, b. means for mounting said jackscrew on said switchgear unit so that said jackscrew is rotatable with respect to said switchgear unit, said jackscrew extending generally parallel to the direction of motion of said switchgear unit within said enclosure, c. a traveling nut mounted on said jackscrew and having a lug projecting radially therefrom, d. said jackscrew being movable axially with respect to said nut when rotated relative to said nut, thereby effecting movement of said switchgear unit if rotated relative to said nut while said nut is held against movement relative to said enclosure, e. an anchoring device fixed to said enclosure and having an opening that is adapted to receive said lug and hold said nut against movement relative to said enclosure when said jackscrew is being rotated to effect movement of said switchgear unit into and out of its fully inserted position, f. means for holding saiD lug in said opening in said anchoring device while said jackscrew is being rotated to effect movement of said switchgear unit comprising; structure fixed to said movable switchgear unit and containing a first slot that extends axially of said jackscrew for receiving said lug while said switchgear unit is moving to and from its fully inserted position, g. said structure also including a second slot extending generally perpendicular to said first slot and communicating with said first slot for receiving said lug when said lug is aligned with said second slot and said nut is rotated in one direction together with said jackscrew, h. rotation in said one direction of said nut together with said jackscrew when said lug is aligned with said second slot causing said lug to withdraw from the opening in said anchoring device and to enter said second slot, thereby uncoupling said nut from said anchoring device, and i. means for causing said nut to rotate together with said jackscrew when said lug is aligned with second slot and said jackscrew is rotated in said one direction.
Claim 2
Dependent Claim
374 words
Electric switchgear comprising an enclosure, a switchgear unit movable into and out of said enclosure, and racking mechanism for moving said switchgear unit into and out of a fully inserted contact engaging position within said enclosure, said racking mechanism comprising: a. a jackscrew, b. means for mounting said jackscrew on said switchgear unit so that said jackscrew is rotatable with respect to said switchgear unit, said jackscrew extending generally parallel to the direction of motion of said switchgear unit within said enclosure, c. a traveling nut mounted on said jackscrew and having a lug projecting radially therefrom, d. said jackscrew being movable axially with respect to said nut when rotated relative to said nut, thereby effecting movement of said switchgear unit if rotated relative to said nut while said nut is held against movement relative to said enclosure, e. an anchoring device fixed to said enclosure and having an opening that is adapted to receive said lug and hold said nut against movement relative to said enclosure when said jackscrew is being rotated to effect movement of said switchgear unit into and out of its fully inserted position, f. means for holding saiD lug in said opening in said anchoring device while said jackscrew is being rotated to effect movement of said switchgear unit comprising; structure fixed to said movable switchgear unit and containing a first slot that extends axially of said jackscrew for receiving said lug while said switchgear unit is moving to and from its fully inserted position, g. said structure also including a second slot extending generally perpendicular to said first slot and communicating with said first slot for receiving said lug when said lug is aligned with said second slot and said nut is rotated in one direction together with said jackscrew, h. rotation in said one direction of said nut together with said jackscrew when said lug is aligned with said second slot causing said lug to withdraw from the opening in said anchoring device and to enter said second slot, thereby uncoupling said nut from said anchoring device, and i. means for causing said nut to rotate together with said jackscrew when said lug is aligned with second slot and said jackscrew is rotated in said one direction.
Claim 3
Dependent Claim
47 words
The switchgear of claim 1 in which said means for causing said nut to rotate together with said jackscrew comprises a friction drive between said jackscrew and said nut which becomes operative when said nut is in a position where its lug aligns with said second slot.
Claim 4
Dependent Claim
38 words
The switchgear of claim 2 in which said friction drive is disabled from causing said nut and said jackscrew to rotate together when said nut is displaced from the location where its lug aligns with said second slot.
Claim 5
Dependent Claim
54 words
The switchgear of claim 1 in which said means for causing said nut to rotate together with said jackscrew comprises a ring of resilient material that is carried by said jackscrew in a position to frictionally engage said nut when said nut is in a position wherein its lug aligns with said second slot.
Claim 6
Dependent Claim
54 words
The switchgear of claim 1 in which at the start of a racking operation coupling of said nut to said anchoring device is effected by rotating said jackscrew together with said nut and said lug in an opposite direction to said one direction, thereby moving said lug into said opening in said anchoring device.
Claim 7
Dependent Claim
56 words
The switchgear unit of claim 5 in which means is provided for limiting movement of said lug in said opposite direction while in said opening in said anchoring device to a position wherein said lug aligns with said first slot and is free to enter said first slot during the early stages of a racking-in operation.
Claim 8
Dependent Claim
71 words
The switchgear of claim 5 in which: a. when said nut is uncoupled from said anchoring device, said lug is positioned in said second slot, b. blocking means is provided for blocking movement of said nut out of a position of alignment with said second slot if rotation of said jackscrew together with said nut in said opposite direction carries said lug past a position of alignment with said first slot.
Claim 9
Dependent Claim
72 words
The switchgear unit of claim 6 in which: a. when said nut is uncoupled from said anchoring device, said lug is positioned in said second slot, b. blocking means is provided for blocking movement of said nut out of a position of alignment with said second slot if rotation of said jackscrew together with said nut in said opposite direction carries said lug past a position of alignment with said first slot.
Claim 10
Dependent Claim
84 words
The switchgear of claim 1 in which: a. preparatory to a racking-in operation said movable switchgear unit is moved within said enclosure into a position wherein said lug aligns with said opening in the anchoring device, b. said nut is coupled to said anchoring device at the start of a racking-in operation by rotating said jackscrew together with said nut in an opposite direction to said one direction, thereby moving said lug out of said second slot into said opening in said anchoring device.
Claim 11
Dependent Claim
129 words
The switchgear of claim 1 in which: a. said second slot comprises one portion into which said lug must be moved to permit said nut to be uncoupleD from said anchoring device, b. said second slot also comprises an extension portion on an opposite side of said first slot from said one portion for receiving said lug should said lug be carried past a position of alignment with said first slot, c. said extension portion of the second slot acts as a locking means for blocking movement of said nut out of a position of alignment with said second slot if rotation of said jackscrew together with said nut in an opposite direction to said one direction carries said lug past a position of alignment with said first slot.
Claim 12
Dependent Claim
95 words
The switchgear unit of claim 1 in which: a. said movable switchgear unit comprises a main working portion and current-carrying studs projecting far out in front of said main working portion for carrying current to and from said main working portion when said switchgear unit is fully inserted, b. said anchoring device is located generally in alignment with said main working portion, considered in the direction of movement of said movable switchgear unit, when said movable switchgear unit is in a position wherein said lug can be withdrawn from the opening in said anchoring device.
Claim 13
Dependent Claim
134 words
The switchgear unit of claim 1 in which: a. the structure of (a), (b), (c), (f), (g), and (i) of claim 1 constitutes a first jackscrew assembly and the anchoring device of (e) of claim 1 constitutes a first anchoring device, b. said first jackscrew assembly is located at one side of said movable switchgear unit for cooperation said first anchoring device, c. a second jackscrew assembly corresponding to said first jackscrew assembly is provided on the opposite side of said movable switchgear unit, and d. a second anchoring device is provided for cooperating with said second jackscrew assembly in substantially the same manner as said first jackscrew assembly cooperates with said first anchoring device, and e. means is provided for mechanically coupling the jackscrews of said two assemblies together for rotation in unison.
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) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |