US3748621A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Locking mechanism
Assignee: S&C Electric Co
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Filing: 1972-09-25
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Granted: 1973-07-24
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Expires: 1992-09-25
Abstract
Abstract A locking mechanism for a removable roller mounted fuse drawer of a high voltage fuse enclosure. Locking levers are mounted on a first shaft adjacent loadbreak connectors so that when the loadbreak connectors are connected to fuse terminals they engage blocking levers causing the levers and shaft to pivot. The shaft is interconnected by a linkage arrangement to a second shaft adjacent the roller mounted fuse drawer. Mounted on the second shaft are blocking cams which engage stops on the fuse drawer to prevent movement of the fuse drawer when the loadbreak connectors are connected. When the loadbreak connectors are manually disconnected from the fuse terminals breaking the circuit to the fuses, the blocking levers and first shaft pivot causing the linkage arrangement to rotate the second shaft and move the blocking cams out of engagement with the drawer stops thus permitting the fuse drawer to be removed from the fuse enclosure. The fuse drawer can then be removed so that the fuses can be tested or replaced. The blocking cams prevent replacement of the fuse drawer in the fuse enclosure if any of the loadbreak connectors are reconnected to the fuse terminals after the fuse drawer is removed from the fuse enclosure. Thus, the fuse drawer can neither be opened nor closed any time a loadbreak connector is connected to the circuit thus preventing either opening of the fuse drawer when the fuses are under electrical load or closing the fuse drawer into an electrically loaded circuit.
Inventors
- 👤 G Sakats
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:00
CPC Classifications
H; H01; H01H; H01H31/00; H01H31/02; H01H31/04; H01H31/12; H01H31/122
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
280 words
In a high voltage switchgear assembly, the assembly comprising a fuse drawer mounted for reciprocal movement between an open position and a closed position, a fuse mounting affixed to the drawer and connected to an electrical power source, a fuse mounted on the fuse mounting, a fuse contact mounted in alignment with the drawer being adapted to receive and make electrical contact with the fuse when the drawer is moved to its closed position and electrically disconnected the fuse when the drawer is moved to its open position, a loadbreak connector electrically connected to the fuse contact and to an electrical load, the loadbreak connector being adapted to be disConnected from the fuse contact to break electrical contact with the fuse contact, a fuse drawer locking mechanism comprising: blocking means for engaging thee loadbreak connector when the loadbreak connector is connected to the fuse contact so that said blocking means moves to a first position, and for disengaging the loadbreak connector when the loadbreak connector is disconnected from the fuse contact so that said blocking means moves to a second position; and lock means operably connected to said blocking means so that said lock means engages the fuse drawer to prevent reciprocal movement of the fuse drawer when said blocking means is in its first position, and so that said lock means disengages the fuse drawer to permit reciprocal movement of the fuse drawer when the loadbreak connector is disconnected from the fuse contact, whereby the fuse drawer is prevented from being moved from its closed position to its open position and from its open position to its closed position until the loadbreak connector is disconnected from the fuse contact.
Claim 2
Dependent Claim
280 words
In a high voltage switchgear assembly, the assembly comprising a fuse drawer mounted for reciprocal movement between an open position and a closed position, a fuse mounting affixed to the drawer and connected to an electrical power source, a fuse mounted on the fuse mounting, a fuse contact mounted in alignment with the drawer being adapted to receive and make electrical contact with the fuse when the drawer is moved to its closed position and electrically disconnected the fuse when the drawer is moved to its open position, a loadbreak connector electrically connected to the fuse contact and to an electrical load, the loadbreak connector being adapted to be disConnected from the fuse contact to break electrical contact with the fuse contact, a fuse drawer locking mechanism comprising: blocking means for engaging thee loadbreak connector when the loadbreak connector is connected to the fuse contact so that said blocking means moves to a first position, and for disengaging the loadbreak connector when the loadbreak connector is disconnected from the fuse contact so that said blocking means moves to a second position; and lock means operably connected to said blocking means so that said lock means engages the fuse drawer to prevent reciprocal movement of the fuse drawer when said blocking means is in its first position, and so that said lock means disengages the fuse drawer to permit reciprocal movement of the fuse drawer when the loadbreak connector is disconnected from the fuse contact, whereby the fuse drawer is prevented from being moved from its closed position to its open position and from its open position to its closed position until the loadbreak connector is disconnected from the fuse contact.
Claim 3
Dependent Claim
150 words
A fuse drawer locking mechanism as claimed in claim 1 wherein said blocking means comprises a first pivotably mounted shaft; a blocking lever mounted on the first shaft and being adapted to engage the loadbreak connector when the loadbreak connector is connected to the fuse contact so that said blocking lever and said first shaft are pivoted to a first position, and to disengage the loadbreak connector when the loadbreak connector is disconnected from the fuse contact so that said blocking lever and said first shaft are pivoted to a second position; a second pivotably mounted shaft; and interconnecting means operably interconnecting said first and second shafts so that said second shaft is moved to a first positon when said first shaft is moved to its first position and so that said second shaft is moved to a second position whe said first shaft is moved to its second position.
Claim 4
Dependent Claim
70 words
A fuse drawer locking mechanism as claimed in claim 2 wherein said lock means comprises: cam means mounted on said second shaft and being adapted to engage the fuse drawer to prevent reciprocal movement of the fuse drawer when said second shaft is in its first position and to disengage the fuse drawer to permit reciprocal movement of the fuse drawer when said second shaft is in its second position.
Claim 5
Dependent Claim
61 words
A fuse drawer locking mechanism as claimed in claim 3 further comprising a multiplicity of abutments mounted on the fuse drawer and wherein said cam means comprises a multiplicity of engaging cams mounted along the length of said second shaft, said cams being positioned to engage one or more of said abutments when said second shaft is in its first position.
Claim 6
Dependent Claim
52 words
A fuse drawer locking mechanism as claimed in claim 2 wherein said interconnecting means comprises: a first lever mounted at a first end on said first shaft; a second lever mounted at a first end on said second shaft; a linkage member connecting the second ends of said first and second levers.
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) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |