US3629529A - Retaining means for operating handle of molded-case electric circuit breaker - Google Patents
Retaining means for operating handle of molded-case electric circuit breaker Download PDFInfo
- Publication number
- US3629529A US3629529A US13974A US3629529DA US3629529A US 3629529 A US3629529 A US 3629529A US 13974 A US13974 A US 13974A US 3629529D A US3629529D A US 3629529DA US 3629529 A US3629529 A US 3629529A
- Authority
- US
- United States
- Prior art keywords
- operating handle
- circuit breaker
- retaining means
- handle
- slot
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- 239000000969 carrier Substances 0.000 description 3
- 241000220317 Rosa Species 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/20—Interlocking, locking, or latching mechanisms
- H01H9/28—Interlocking, locking, or latching mechanisms for locking switch parts by a key or equivalent removable member
- H01H9/286—Interlocking, locking, or latching mechanisms for locking switch parts by a key or equivalent removable member making use of a removable locking part acting directly on the operating part
Definitions
- An object of the invention is to provide retaining means for holding an operating handle of a molded-case electric circuit breaker in ON position while it is being biased toward OFF position by the internal-operating mechanism of the circuit breaker due to latching of the movable contact arm carrier in OFF position by a remotely and electromagnetically operable latching means. Upon release of the latching means, the contact arms move to ON position, being biased theretoward by the internal-operating mechanism of the circuit breaker due to the holding of the operating handle in ON position.
- the system is particularly useful when it is considered necessary to close a number of circuit breakers at exactly the same time.
- FIG. I is a fragmentary perspective view of a circuit breaker having retaining means constructed in accordance with an embodiment of the invention provided on the operating handle thereof and holding the handle in ON position;
- FIG. 2 is a front elevational view of the retaining means of FIG. I;
- FIG. 3 is a rear elevational view of the retaining means of FIG. 1;
- FIG. 4 is a left side elevational view of the retaining means of FIG. I.
- FIG. 5 is a sectional view taken along the line 5-5 of FIG. 4.
- FIG. I a fragmentary front portion of a casing of an electric circuit breaker is shown.
- a raised portion I00 of the casing 10 defines an opening or slot 12 through which an operating handle I3 projects, the handle 13 being pivotable about an axis disposed within the casing and the projecting portion of the handle normally being reciprocable within the slot 12 between ON and OFF positions in a manner well understood in the art.
- the operating handle 13 is provided with retaining means 14 constructed in accordance with the invention.
- the retaining means 14 includes a two-piece body having a base 16 and a cover 17 secured together by a pair of socket-head screws 18.
- the base I6 and the cover 17 are each wider than the slot 12, but they are narrowed adjacent their lower ends to provide lower extensions 16a and 17a which fit within the slot 12.
- the base 16 including the extension 16a is provided with a recess 16b for receiving the handle I3, the cover I7 being provided with a matching recess 17b.
- the extension I60 is also narrower than the remainder of the base 16 in a direction longitudinal of the slot 12, as indicated by the inwardly offset surface 160 in FIG. 4.
- a double-shouldered screw 20 having a pair of generally flat locking members 21 and 22 pivotally mounted thereon is threaded into the cover 17.
- the screw 20 has an inner end portion of relatively small diameter threaded tightly into the cover 17 until a shoulder on an intermediate unthreaded portion of relatively large diameter contacts the cover 17.
- the locking members 21 and 22 are pivotally mounted on the intermediate portion and held against outward movement axially of the screw 20 by an enlarged head portion of the screw, as best shown in FIG. 4.
- the locking members respectively include handle portions 21a and 22a respectively having facing tang portions 21b and 22b on which a compression spring 24 is mounted.
- the locking members respectively include locking foot portions 21c and 22 which are biased by the spring 24 into engagement respectively with cross grooves 25 and 26 provided in the casing portion on opposite sides of the slot 12 adjacent the handle I3 when it IS III ON position.
- the handle portion 21a is outwardly offset into the plane of locking member 22, to provide clearance for the spring 24.
- the retaining means 14 is placed over the handle I3 while the handle portions 21a and 22a of the locking members are squeezed together against the force of the spring 24, enabling the locking foot portions 21c and 22c to enter the slot 12.
- the locking members are then released and the circuit breaker handle 13 is moved to ON position, at which the locking foot portions 21c and 220 respectively enter the grooves 25 and 26 under the influence of the spring 24.
- the handle 13 is then held in ON position by the retaining means 14, though biased toward OFF position by the internaloperating mechanism of the circuit breaker due to the latching of the contact arm carriers in OFF position.
- the movable contacts of the circuit breaker move to closed position.
- several circuit breakers may be made to close at exactly the same time by operation of a single electrical signal.
- retaining means 14 has been described with respect to an embodiment of the invention in which the retaining means is mountable on the operating handles of existing circuit breakers as a separate attachment, it is obvious that members equivalent in function to the screw 20, the locking members 21 and 22, and the spring 24 could be contained with the operating handle 13 in appropriate grooves and recesses as the circuit breakers are furnished from the factory.
- Retaining means for holding a pivotally mounted operating handle of an electric circuit breaker in ON position in a slot through which it protrudes from a casing of the circuit breaker while it is biased toward OFF position in the slot by an intemal-operating mechanism of the circuit breaker due to a latched OFF condition of movable contact arms of the circuit breaker, the retaining means comprising a locking member pivotally mounted on the operating handle for movement about a pivotal axis extending perpendicularly to a pivotal axis of the operating handle and movable with respect thereto when the operating handle is in ON position to dispose a portion thereof in an elongated groove formed in the casing of the circuit breaker adjacent the slot and extending transversely of the direction of movement of the operating handle in the slot.
- Retaining means as claimed in claim I wherein there are a pair of the locking members pivotally mounted on the operating handle for movement about the pivotal axis extending perpendicularly to the pivotal axis of the operating handle and each ismovable with respect thereto when the operating handle is in ON position to dispose a portion thereof in a respective one of a pair of elongated grooves formed in the casing of the circuit breaker adjacent the slot respectively on opposite sides thereof and extending transversely of the direction of movement of the operating handle in the slot.
- each of the locking members includes a handle portion and the biasing of the locking members is effected by a spring disposed between the handle portions of the locking members.
- Retaining means as claimed in claim I including a body having a recess therein which the operating handle is received, and wherein the locking member is mounted on the body.
Landscapes
- Breakers (AREA)
Abstract
The portion of a circuit breaker casing defining an opening for a pivotable operating handle is provided with a pair of grooves respectively disposed on opposite sides of the opening adjacent an ON position of the handle and extending transversely of the direction of movement of the handle. A retaining means provided on the handle includes a pair of pivotally mounted locking members having end portions insertable respectively in the grooves to lock the handle in ON position while it is being biased toward OFF position by the internal operating mechanism of the circuit breaker.
Description
United States Patent Inventor Robert E. Dietz Cedar Rapids, Iowa Appl. No. 13,974
Filed Feb. 25, 1970 Patented Dee. 2I, I971 Assignee Square D Company Park Ridge, III.
RETAINING MEANS FOR OPERATING HANDLE OF MOLDED-CASE ELECTRIC CIRCUIT BREAKER 5 Claims, 5 Drawing Figs.
US. Cl 200/42 Int. Cl H021 1/10 Field of Search ZOO/42:42
[56] References Cited UNITED STATES PATENTS 2,983,799 5/1961 Osieja et al. J 200/42 T 3, I 53,707 10/1964 Barnes 200/42 T 3,388,224 6/1968 Higgins 200/42 T Primary Examiner-Herman .I. Hohauser Attorneysl*larold J. Rathbun and Paul 1. Rose ABSTRACT: The portion of a circuit breaker casing defining an opening for a pivotable operating handle is provided with a pair of grooves respectively disposed on opposite sides of the opening adjacent an ON position of the handle and extending transversely of the direction of movement of the handle. A retaining means provided on the handle includes a pair of pivotally mounted locking members having end portions insertable respectively in the grooves to lock the handle in ON position while it is being biased toward OFF position by the in ternal operating mechanism of the circuit breaker.
PATENTEI] DEBZI BTI 2Ib 24 22b l4 l6a INVENTOR.
ROBERT E. DIE TZ RETAINING MEANS FOR OPERATING IIANDLE OF MOLDED-CASE ELECTRIC CIRCUIT BREAKER This invention relates to retaining means for the handle of a circuit breaker having a remotely and electromagnetically operable contact arm carrier latching means, as disclosed in copending application, Ser. No. 866,668, filed Nov. 18, 1969, and now U.S. Pat. No. 3,601,724, issued Aug. 24, I97l.
An object of the invention is to provide retaining means for holding an operating handle of a molded-case electric circuit breaker in ON position while it is being biased toward OFF position by the internal-operating mechanism of the circuit breaker due to latching of the movable contact arm carrier in OFF position by a remotely and electromagnetically operable latching means. Upon release of the latching means, the contact arms move to ON position, being biased theretoward by the internal-operating mechanism of the circuit breaker due to the holding of the operating handle in ON position. The system is particularly useful when it is considered necessary to close a number of circuit breakers at exactly the same time.
Other objects and advantages will become apparent when the following specification is considered along with the accompanying drawings, in which:
FIG. I is a fragmentary perspective view of a circuit breaker having retaining means constructed in accordance with an embodiment of the invention provided on the operating handle thereof and holding the handle in ON position;
FIG. 2 is a front elevational view of the retaining means of FIG. I;
FIG. 3 is a rear elevational view of the retaining means of FIG. 1;
FIG. 4 is a left side elevational view of the retaining means of FIG. I; and
FIG. 5 is a sectional view taken along the line 5-5 of FIG. 4.
With reference to FIG. I, a fragmentary front portion of a casing of an electric circuit breaker is shown. A raised portion I00 of the casing 10 defines an opening or slot 12 through which an operating handle I3 projects, the handle 13 being pivotable about an axis disposed within the casing and the projecting portion of the handle normally being reciprocable within the slot 12 between ON and OFF positions in a manner well understood in the art. The operating handle 13 is provided with retaining means 14 constructed in accordance with the invention.
In the embodiment of the invention shown, the retaining means 14 includes a two-piece body having a base 16 and a cover 17 secured together by a pair of socket-head screws 18. For the most part, the base I6 and the cover 17 are each wider than the slot 12, but they are narrowed adjacent their lower ends to provide lower extensions 16a and 17a which fit within the slot 12. The base 16 including the extension 16a is provided with a recess 16b for receiving the handle I3, the cover I7 being provided with a matching recess 17b. The extension I60 is also narrower than the remainder of the base 16 in a direction longitudinal of the slot 12, as indicated by the inwardly offset surface 160 in FIG. 4.
A double-shouldered screw 20 having a pair of generally flat locking members 21 and 22 pivotally mounted thereon is threaded into the cover 17. The screw 20 has an inner end portion of relatively small diameter threaded tightly into the cover 17 until a shoulder on an intermediate unthreaded portion of relatively large diameter contacts the cover 17. The locking members 21 and 22 are pivotally mounted on the intermediate portion and held against outward movement axially of the screw 20 by an enlarged head portion of the screw, as best shown in FIG. 4.
The locking members respectively include handle portions 21a and 22a respectively having facing tang portions 21b and 22b on which a compression spring 24 is mounted. At their other ends on the opposite side of the screw 20 the locking members respectively include locking foot portions 21c and 22 which are biased by the spring 24 into engagement respectively with cross grooves 25 and 26 provided in the casing portion on opposite sides of the slot 12 adjacent the handle I3 when it IS III ON position. As best shown in FIG. 4, the handle portion 21a is outwardly offset into the plane of locking member 22, to provide clearance for the spring 24. I
With the contact arm carriers latched in OFF position by latching means such as disclosed in the aforementioned copending application, and with the handle I3 of the circuit breaker in OFF position, the retaining means 14 is placed over the handle I3 while the handle portions 21a and 22a of the locking members are squeezed together against the force of the spring 24, enabling the locking foot portions 21c and 22c to enter the slot 12. The locking members are then released and the circuit breaker handle 13 is moved to ON position, at which the locking foot portions 21c and 220 respectively enter the grooves 25 and 26 under the influence of the spring 24. The handle 13 is then held in ON position by the retaining means 14, though biased toward OFF position by the internaloperating mechanism of the circuit breaker due to the latching of the contact arm carriers in OFF position. Upon release of the contact arm carriers by remote control, the movable contacts of the circuit breaker move to closed position. Thus, several circuit breakers may be made to close at exactly the same time by operation of a single electrical signal.
Although the retaining means 14 has been described with respect to an embodiment of the invention in which the retaining means is mountable on the operating handles of existing circuit breakers as a separate attachment, it is obvious that members equivalent in function to the screw 20, the locking members 21 and 22, and the spring 24 could be contained with the operating handle 13 in appropriate grooves and recesses as the circuit breakers are furnished from the factory.
I claim:
1. Retaining means for holding a pivotally mounted operating handle of an electric circuit breaker in ON position in a slot through which it protrudes from a casing of the circuit breaker while it is biased toward OFF position in the slot by an intemal-operating mechanism of the circuit breaker due to a latched OFF condition of movable contact arms of the circuit breaker, the retaining means comprising a locking member pivotally mounted on the operating handle for movement about a pivotal axis extending perpendicularly to a pivotal axis of the operating handle and movable with respect thereto when the operating handle is in ON position to dispose a portion thereof in an elongated groove formed in the casing of the circuit breaker adjacent the slot and extending transversely of the direction of movement of the operating handle in the slot.
2. Retaining means as claimed in claim I wherein there are a pair of the locking members pivotally mounted on the operating handle for movement about the pivotal axis extending perpendicularly to the pivotal axis of the operating handle and each ismovable with respect thereto when the operating handle is in ON position to dispose a portion thereof in a respective one of a pair of elongated grooves formed in the casing of the circuit breaker adjacent the slot respectively on opposite sides thereof and extending transversely of the direction of movement of the operating handle in the slot.
3. Retaining means as claimed in claim 2 wherein the locking members are elongated and pivotally mounted respectively generally centrally thereof, and opposite end portions of each are biased respectively away from corresponding opposite end portions of the other.
4. Retaining means as claimed in claim 3 wherein each of the locking members includes a handle portion and the biasing of the locking members is effected by a spring disposed between the handle portions of the locking members.
5. Retaining means as claimed in claim I including a body having a recess therein which the operating handle is received, and wherein the locking member is mounted on the body.
Claims (5)
1. Retaining means for holding a pivotally mounted operating handle of an electric circuit breaker in ON position in a slot through which it protrudes from a casing of the circuit breaker while it is biased toward OFF position in the slot by an internal-operating mechanism of the circuit breaker due to a latched OFF condition of movable contact arms of the circuit breaker, the retaining means comprising a locking member pivotally mounted on the operating handle for movement about a pivotal axis extending perpendicularly to a pivotal axis of the operating handle and movable with respect thereto when the operating handle is in ON position to dispose a portion thereof in an elongated groove formed in the casing of the circuit breaker adjacent the slot and extending transversely of the direction of movement of the operating handle in the slot.
2. Retaining means as claimed in claim 1 whErein there are a pair of the locking members pivotally mounted on the operating handle for movement about the pivotal axis extending perpendicularly to the pivotal axis of the operating handle and each is movable with respect thereto when the operating handle is in ON position to dispose a portion thereof in a respective one of a pair of elongated grooves formed in the casing of the circuit breaker adjacent the slot respectively on opposite sides thereof and extending transversely of the direction of movement of the operating handle in the slot.
3. Retaining means as claimed in claim 2 wherein the locking members are elongated and pivotally mounted respectively generally centrally thereof, and opposite end portions of each are biased respectively away from corresponding opposite end portions of the other.
4. Retaining means as claimed in claim 3 wherein each of the locking members includes a handle portion and the biasing of the locking members is effected by a spring disposed between the handle portions of the locking members.
5. Retaining means as claimed in claim 1 including a body having a recess therein which the operating handle is received, and wherein the locking member is mounted on the body.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US1397470A | 1970-02-25 | 1970-02-25 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3629529A true US3629529A (en) | 1971-12-21 |
Family
ID=21762806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US13974A Expired - Lifetime US3629529A (en) | 1970-02-25 | 1970-02-25 | Retaining means for operating handle of molded-case electric circuit breaker |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3629529A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4704504A (en) * | 1986-07-21 | 1987-11-03 | Jones Samuel V | Pinching deactivator for automobile electric switches |
| US5077452A (en) * | 1990-08-20 | 1991-12-31 | Mathers Lee F | Doorbell block |
| US5165528A (en) * | 1991-09-18 | 1992-11-24 | The United States Of America As Represented By The United States Department Of Energy | Circuit breaker lockout device |
| US5181602A (en) * | 1991-09-18 | 1993-01-26 | The United States Of America As Represented By The United States Department Of Energy | Lockout device for high voltage circuit breaker |
| US5270503A (en) * | 1992-10-26 | 1993-12-14 | Frye James A | Electric circuit lock-out safety device |
| US5290979A (en) * | 1993-04-19 | 1994-03-01 | Eaton Corporation | Handle block for electrical switching device |
| US5412167A (en) * | 1993-10-08 | 1995-05-02 | Eaton Corporation | Locking device for an electrical switch |
| US5593020A (en) * | 1995-03-07 | 1997-01-14 | Alexander; Richard L. | Apparatus for locking a circuit breaker, and methods for forming and using same |
| WO1997043776A1 (en) * | 1996-05-14 | 1997-11-20 | Square D Company | Circuit breaker with handle locking device |
| US6469264B2 (en) | 2001-01-29 | 2002-10-22 | Brady Worldwide, Inc. | Switch lever lock out assembly |
| US6727441B2 (en) | 2002-09-04 | 2004-04-27 | Brady Worldwide, Inc. | Switch lever lock out assembly |
| US20040159530A1 (en) * | 2001-03-21 | 2004-08-19 | Benda Steven J. | Circuit breaker lock-out assembly |
| CN102222582A (en) * | 2010-04-14 | 2011-10-19 | 鸿富锦精密工业(深圳)有限公司 | Electronic devices with buttons that prevent misoperation |
| TWI469164B (en) * | 2010-04-23 | 2015-01-11 | Hon Hai Prec Ind Co Ltd | Electronic device having button without risk of accidental activation |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2983799A (en) * | 1958-07-28 | 1961-05-09 | Fed Pacific Electric Co | Switching apparatus with lock-off device |
| US3153707A (en) * | 1960-10-10 | 1964-10-20 | North American Aviation Inc | Toggle switch locking device |
| US3388224A (en) * | 1964-08-31 | 1968-06-11 | Ite Circuit Breaker Ltd | Circuit breaker locking device |
-
1970
- 1970-02-25 US US13974A patent/US3629529A/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2983799A (en) * | 1958-07-28 | 1961-05-09 | Fed Pacific Electric Co | Switching apparatus with lock-off device |
| US3153707A (en) * | 1960-10-10 | 1964-10-20 | North American Aviation Inc | Toggle switch locking device |
| US3388224A (en) * | 1964-08-31 | 1968-06-11 | Ite Circuit Breaker Ltd | Circuit breaker locking device |
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4704504A (en) * | 1986-07-21 | 1987-11-03 | Jones Samuel V | Pinching deactivator for automobile electric switches |
| US5077452A (en) * | 1990-08-20 | 1991-12-31 | Mathers Lee F | Doorbell block |
| US5165528A (en) * | 1991-09-18 | 1992-11-24 | The United States Of America As Represented By The United States Department Of Energy | Circuit breaker lockout device |
| US5181602A (en) * | 1991-09-18 | 1993-01-26 | The United States Of America As Represented By The United States Department Of Energy | Lockout device for high voltage circuit breaker |
| US5270503A (en) * | 1992-10-26 | 1993-12-14 | Frye James A | Electric circuit lock-out safety device |
| US5290979A (en) * | 1993-04-19 | 1994-03-01 | Eaton Corporation | Handle block for electrical switching device |
| US5412167A (en) * | 1993-10-08 | 1995-05-02 | Eaton Corporation | Locking device for an electrical switch |
| US5593020A (en) * | 1995-03-07 | 1997-01-14 | Alexander; Richard L. | Apparatus for locking a circuit breaker, and methods for forming and using same |
| WO1997043776A1 (en) * | 1996-05-14 | 1997-11-20 | Square D Company | Circuit breaker with handle locking device |
| US6469264B2 (en) | 2001-01-29 | 2002-10-22 | Brady Worldwide, Inc. | Switch lever lock out assembly |
| US20040159530A1 (en) * | 2001-03-21 | 2004-08-19 | Benda Steven J. | Circuit breaker lock-out assembly |
| US6844512B2 (en) * | 2001-03-21 | 2005-01-18 | Brady Worldwide, Inc. | Circuit breaker lock-out assembly |
| US6727441B2 (en) | 2002-09-04 | 2004-04-27 | Brady Worldwide, Inc. | Switch lever lock out assembly |
| CN102222582A (en) * | 2010-04-14 | 2011-10-19 | 鸿富锦精密工业(深圳)有限公司 | Electronic devices with buttons that prevent misoperation |
| US20110253518A1 (en) * | 2010-04-14 | 2011-10-20 | Hon Hai Precision Industry Co., Ltd. | Electronic device having button capable of preventing accidental depression |
| US8283584B2 (en) * | 2010-04-14 | 2012-10-09 | Fu Tai Hua Industry (Shenzhen) Co., Ltd. | Electronic device having button capable of preventing accidental depression |
| CN102222582B (en) * | 2010-04-14 | 2015-01-28 | 鸿富锦精密工业(深圳)有限公司 | Electronic device with buttons capable of preventing misoperation |
| TWI469164B (en) * | 2010-04-23 | 2015-01-11 | Hon Hai Prec Ind Co Ltd | Electronic device having button without risk of accidental activation |
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