Patent US4408173A successfully refreshed from Google Patents.
US4408173A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric switch
Assignee: ABB Norden Holding AB
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Filing: 1981-10-28
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Granted: 1983-10-04
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Expires: 2001-10-28
Abstract
Abstract An electromagnetically operated electric switch combines the function of a contactor and a current-limiting circuit-breaker. The contact assembly of the switch includes two contact systems, which are different in function, with a fixed contact which is common to both systems. The first contact system is intended for normal operating current connections, whereas the other contact system is intended for breaking short-circuit currents. The contact-making elements in the two contact systems can be made of different contact materials, in order to obtain a long electrical and mechanical life.
Inventors
- 👤 Bo Adlerteg
- 👤 Lennart Grees
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:02
CPC Classifications
H; H01; H01H; H01H89/00; H01H89/06; H01H71/00; H01H71/10; H01H71/66; H01H71/68; H01H77/00; H01H77/02; H01H77/10
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
200 words
An electromagnetically operable electric switch having a predetermined current rating comprising: at least one breaking unit comprising: a first openable contact system; and a second openable contact system electrically series connected to said first openable contact system; said first openable contact system comprising: a movable first contact; a fixed second contact; and electromagnetic means controlling engagement of said first contact with said second contact; said second openable contact system comprising: a movable third contact normally engaged with said fixed second contact and disengageable from said fixed second contact exclusively in response to electrodynamic forces created by the passage of a current through said switch greater than ten times said predetermined current rating and comprising a second material having properties suitable for interrupting short circuit currents; said fixed second contact being disposed intermediate said first and third contacts and comprising: a first contact element forming a part of said first contact system and comprising a first material suitable for making and breaking currents occurring during normal operation of said switch; and a second contact element forming a part of said second contact system and electrically connected to said first contact element and comprising said second material different from said first material.
Claim 2
Dependent Claim
200 words
An electromagnetically operable electric switch having a predetermined current rating comprising: at least one breaking unit comprising: a first openable contact system; and a second openable contact system electrically series connected to said first openable contact system; said first openable contact system comprising: a movable first contact; a fixed second contact; and electromagnetic means controlling engagement of said first contact with said second contact; said second openable contact system comprising: a movable third contact normally engaged with said fixed second contact and disengageable from said fixed second contact exclusively in response to electrodynamic forces created by the passage of a current through said switch greater than ten times said predetermined current rating and comprising a second material having properties suitable for interrupting short circuit currents; said fixed second contact being disposed intermediate said first and third contacts and comprising: a first contact element forming a part of said first contact system and comprising a first material suitable for making and breaking currents occurring during normal operation of said switch; and a second contact element forming a part of said second contact system and electrically connected to said first contact element and comprising said second material different from said first material.
Claim 3
Dependent Claim
60 words
An electric switch according to claim 1, wherein said electromagnetic means comprises an armature, means mechanically connecting said armature to said first contact, and, an electromagnet for moving said armature between a first position in which said first and second contacts engage one another and a second position in which said first and second contacts are disengaged from one another.
Claim 4
Dependent Claim
24 words
An electric switch according to claim 1, wherein said first material is silver cadmium oxide and said second material is silver alloyed with tungsten.
Claim 5
Dependent Claim
48 words
An electric switch according to claim 1, wherein said first, second and third contacts form a loop-formed current path, whereby said third contact during passage of current therethrough, is influenced by an electrodynamic force in a direction tending to separate it from engagement with said fixed second contact.
Claim 6
Dependent Claim
23 words
An electric switch according to claim 1, wherein said third contact is biased by spring means into engagement with said fixed second contact.
Claim 7
Dependent Claim
35 words
An electric switch according to claim 1, and comprising two of said breaking units electrically series-connected with one another, wherein said first contacts of said two breaking units are combined to form a bridge contact.
Claim 8
Dependent Claim
79 words
An electric switch according to claim 1, and comprising two of said breaking units electrically series-connected with one another, wherein said third contacts of said two breaking units are mechanically interconnected by at least one tension spring means, which is arranged in such a way that, when said third contacts during an opening movement pass an intermediate position, said tension spring means changes from influencing said third contacts in a contact-closing direction to influencing them in a contact-opening direction.
Claim 9
Dependent Claim
24 words
An electric switch according to claim 1, wherein said first material is silver cadmium oxide and said second material is silver alloyed with graphite.
Claim 10
Dependent Claim
24 words
An electric switch according to claim 1, wherein said first material is silver cadmium oxide and said second material is silver alloyed with nickel.
References Cited (Backward Citations)
US4258343A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |