Systems and methods for locking a circuit breaker

Patent metadata

Field	Value
Publication number	US-9812268-B2
Application number	US-201615041155-A
Country	US
Kind code	B2
Filing date	Feb 11, 2016
Priority date	Feb 11, 2016
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A circuit breaker includes an accessory pocket, an accessory cover and a locking device to lock the circuit breaker such that an unauthorized switching of the circuit breaker from OFF to ON or from ON to OFF states is prevented. The locking device includes a first subassembly including a pocket housing. The first subassembly is configured to be installed in the accessory pocket. The locking device further includes a second subassembly including a cylinder lock. The second subassembly is configured to be mounted to the accessory cover. The first subassembly and the second subassembly are configured to self align upon final assembly of the circuit breaker to perform a locking function of the circuit breaker. In this way, the locking device prevents circumvention of a locking feature and selectively provides an ability to lock in an ON state of the circuit breaker.

First claim

What is claimed is:

1. A key locking device accessory for use with a circuit breaker, the key locking device accessory comprising:
a locking device to lock the circuit breaker such that an unauthorized person is prevented from switching the circuit breaker from an OFF state to an ON state or from the ON state to the OFF state, the locking device including:
a first subassembly including a pocket housing, the first subassembly is configured to be installed in an accessory pocket,
a second subassembly including a cylinder lock, the second subassembly is configured to be mounted to an accessory cover, and
wherein the first subassembly and the second subassembly are configured to self align upon final assembly of the circuit breaker to perform a locking function of the circuit breaker, wherein the first subassembly including a cover to enclose a locking mechanism that interfaces with an operating mechanism of the circuit breaker.

2. The key locking device accessory of claim 1 , wherein the locking mechanism includes:
a guide pin either attached to the pocket housing or is held in cups between the pocket housing and the cover;
a return spring;
a locking pin subassembly having a locking pin carrier with at least one locking pin attached; and
a slider to be housed in the pocket housing of the first subassembly, the slider having a hollow cylinder.

3. The key locking device accessory of claim 2 , wherein the second subassembly includes:
a lock housing to mount the cylinder lock of the second subassembly, the lock housing having a snap; and
a component including a flipper and at least one actuating finger.

4. The key locking device accessory of claim 3 , wherein the accessory cover having a cylinder lock mounting hole to install the second subassembly using the snap of the lock housing.

5. A circuit breaker, comprising:
an accessory pocket;
an accessory cover; and
a locking device to lock the circuit breaker such that an unauthorized person is prevented from switching the circuit breaker from an OFF state to an ON state or from the ON state to the OFF state, the locking device including:
a first subassembly including a pocket housing, the first subassembly is configured to be installed in the accessory pocket,
a second subassembly including a cylinder lock, the second subassembly is configured to be mounted to the accessory cover, and
wherein the first subassembly and the second subassembly are configured to self align upon final assembly of the circuit breaker to perform a locking function of the circuit breaker, wherein the first subassembly including a cover to enclose a locking mechanism that interfaces with an operating mechanism of the circuit breaker.

6. The circuit breaker of claim 5 , wherein the pocket housing having one or more snaps and one or more hooks and the accessory pocket having guides to ensure placement for installing the first subassembly in the accessory pocket by snapping it in place.

7. The circuit breaker of claim 5 , wherein the locking mechanism includes:
a guide pin either attached to the pocket housing or is held in cups between the pocket housing and the cover;
a return spring;
a locking pin subassembly having a locking pin carrier with at least one locking pin attached; and
a slider to be housed in the pocket housing of the first subassembly, the slider having a hollow cylinder.

8. The circuit breaker of claim 7 , wherein the locking pin carrier having a hole to allow the at least one locking pin to be mounted about the hollow cylinder that is provided on the slider.

9. The circuit breaker of claim 7 , wherein the return spring is installed about the guide pin between the locking pin subassembly and the pocket housing to aid in the locking mechanism return and to maintain a contact between the locking pin carrier and the slider.

10. The circuit breaker of claim 7 , wherein the cover affixes onto the pocket housing and constrains the guide pin.

11. The circuit breaker of claim 7 , wherein the pocket housing including first and second holes to allow for one or more locking pins to protrude through the pocket housing and provide alignment once the locking pin subassembly is installed onto the guide pin in the pocket housing.

12. The circuit breaker of claim 7 , further comprising:
one or more blocking tabs molded over an exposed end of an ON locking pin to provide access to a feature of locking the circuit breaker in an ON state by a user by mechanically modifying the locking pin subassembly by removing the one or more blocking tabs to fully expose the ON locking pin.

13. The circuit breaker of claim 7 , wherein the second subassembly includes
a lock housing to mount the cylinder lock of the second subassembly, the lock housing having a snap; and
a component including a flipper and at least one actuating finger.

14. The circuit breaker of claim 13 , wherein the accessory cover having a cylinder lock mounting hole to install the second subassembly using the snap of the lock housing.

15. The circuit breaker of claim 13 , wherein when the circuit breaker is locked with the second subassembly, the flipper captures the guide pin locking the second subassembly to the first subassembly thus preventing the separation of the first and second sub-assemblies.

16. A method of locking a circuit breaker, the method comprising:
providing a first locking device subassembly including a pocket housing, the first locking device subassembly is configured to be installed in an accessory pocket; and
providing a second locking device subassembly including a cylinder lock, the second locking device subassembly is configured to be mounted to an accessory cover, wherein the first locking device subassembly and the second locking device subassembly are configured to self align upon final assembly of the circuit breaker to perform a locking function of the circuit breaker such that an unauthorized person is prevented from switching the circuit breaker from an OFF state to an ON state or from the ON state to the OFF state, wherein the first locking device subassembly including a cover to enclose a locking mechanism that interfaces with an operating mechanism of the circuit breaker, wherein the locking mechanism includes:
a guide pin either attached to the pocket housing or is held in cups between the pocket housing and the cover;
a return spring;
a locking pin subassembly having a locking pin carrier with at least one locking pin attached; and
a slider to be housed in the pocket housing of the first locking device subassembly, the slider having a hollow cylinder.

17. The method of claim 16 , wherein the second locking device subassembly includes:
a lock housing to mount the cylinder lock of the second locking device subassembly, the lock housing having a snap; and
a component including a flipper and at least one actuating finger.

Assignees

• Siemens Ag

Inventors

• Cowans John Quentin

Classifications

• H01H71/1054 Primary

  Means for avoiding unauthorised release · CPC title

• E05B65/006

  for covers or panels (for manholes E02D29/1427; for holes enabling access to installations in buildings E04F19/08; for pressure vessels F16J13/00) · CPC title

• H01H9/285 Primary

  Locking mechanisms incorporated in the switch assembly and operable by a key or a special tool · CPC title

• E05B55/005

  Cylindrical or tubular locks · CPC title