Circuit breaker lock-out assembly

A circuit breaker lock-out assembly which is engageable with a circuit breaker includes a body having a top and a bottom joined by walls. The walls define a passageway extending from the body top to the body bottom. A button having one end extending into the body passageway through the body top is movable between a lock position and an unlock position. A pair of leaf springs are fixed to the button, and extend through the passageway. A nose extends from the body bottom, ant is engageable with the leaf springs. A pin extends from each of the leaf springs. Each pin is engageable with a hole formed in the circuit breaker walls adjacent the switch tongue, wherein slidable movement of the button toward at least one of the lock position and unlock position engages the leaf spring with the nose to move each pin relative to the hole.

BACKGROUND OF THE INVENTION

The field of invention is switch lever lock-outs for locking switch levers in a desired position, and more particularly to switch lever lockouts which engage holes formed in switch cavity walls.

Switches are used in many applications to control the flow of electrical energy. The switches can be used to redirect electrical energy from one circuit to another, and can be used to stop the flow of electrical energy through a circuit. In both cases the circuits become de-energized, that is without a voltage.

One particular type of switch is a circuit breaker which cuts off the flow of electrical energy when the flow of electrical energy through the switch exceeds a predetermined value. Many of these circuit breakers include a switch tongue movable between an “On” position and an “Off” position. Walls adjacent the switch tongue between the “On” and “Off” positions define a switch tongue cavity. Opposing holes in the wall can receive pins to prevent movement of the switch tongue.

Maintenance personnel often use a circuit breaker to interrupt the flow of electrical energy through a, circuit when the circuit, or electrical components connected thereto, require maintenance. The circuit breaker, however, is often remote from the location requiring maintenance. Therefore, it is desirable to lock out the circuit breaker to prevent an individual from inadvertently energizing the circuit while maintenance is being performed.

A known circuit breaker lock-out disclosed in French Patent No. 2,424,619 shows leaf springs having pins which engage the inwardly opening holes of the switch tongue cavity walls. However, operation of the lock-out is difficult, and requires two hands to engage and disengage the lock-out from the circuit breaker. Therefore, a need exists for an effective, easy to use, circuit breaker lock-out assembly.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a circuit breaker lockout assembly which is engageable with a circuit breaker. The assembly includes a body having a top and a bottom joined by walls. The walls define a passageway extending from the body top to the body bottom A button having one end extending into the body passageway through the body top is movable between a lock position and an unlock position. A pair of leaf springs is fixed to the button, and extends through the body passageway. A nose extends from the body bottom, and is engageable with the leaf springs. A pin extends from each of the leaf springs. Each pin is engageable with a hole formed in the circuit breaker walls adjacent the switch tongue, wherein slidable movement of the button toward at least one of the lock position and unlock position engages the leaf spring with the nose to move each pin relative to the hole.

A general objective of the present invention is to provide a circuit breaker lock-out assembly which is engageable with holes formed in walls adjacent a circuit breaker tongue. This objective is accomplished by providing leaf springs fixed to the button, wherein pins extending from each leaf spring are engageable with the holes formed in the walls adjacent the circuit breaker tongue.

Another objective of the present invention is to provide a circuit breaker lock-out assembly which is easily operated. This objective is accomplished by providing leaf springs fixed to a slidable button and arms which extend from the assembly body which are engageable with user fingers to allow single handed operation of the circuit breaker lock-out assembly.

The foregoing and other objectives and advantages of the invention will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown by way of illustration a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIGS. 1-4, a circuit breaker lock-out assembly10is engageable with a circuit breaker12to lock-out the circuit breaker12and prevent undesired operation. The lock-out assembly10includes a hollow body14having an open top16and open bottom18. A button20slidably inserted into the body top16retains a pair of opposing leaf springs22which extend through the body bottom18. A nose24extending from the body bottom18engages the leaf springs22to locks the circuit breaker12. Advantageously, the assembly10is operable by a user using one hand.

The circuit breaker12includes a switch tongue26movable between an “On” position and an “Off” position Walls28adjacent the switch tongue26between the “On” and “Off” positions define a switch tongue cavity30. Opposing holes32in the adjacent walls28can receive pins34to prevent movement of the switch tongue26. The circuit breakers can be any commercially available circuit breaker having a switch tongue movable between two or more positions, and having holes formed in opposing walls adjacent the switch tongue which can receive pins.

The circuit breaker lock-out assembly body14includes a front wall36and rear wall38joined by side walls40. The walls36,38,40define a passageway42extending from the open body top16to the open body bottom18. A step44formed in each side wall40can engage the nose24and prevent slidable movement of the nose24further into the passageway42. A cleat slide opening46having an upper end48and a lower end50is formed in the body front wall36, and receives cleats52,54extending from the button20and nose24. Preferably, a cleat slide opening (not shown) is also formed in the body rear wall38, and also receives cleats (not shown) extending from the button20and nose24.

Opposing arms56extend outwardly from each side wall40for engagement by user fingers. The arms56provide a grasping point for the user to enable single handed operation of the assembly10. The exterior surface58of each side wall40below the arms56can be arcuately shaped to further accommodate the finger shape of the user.

The button20includes a base62having a bottom64slidably inserted into the passageway42through the open body top16. A base top66and the base bottom64are joined by front and rear faces68. A head70fixed to the base top66provides a thumb engagement surface for urging the button20into the body passageway42along an assembly axis60extending through the body passageway42.

The button20slidably engages the body walls36,38,40for slidable movement in the passageway42along the assembly axis60. The button20is slidable between a lock position (shown inFIGS. 1 and 3) and an unlock position (shown in FIGS.2and4). In the lock position, the button20is only partially inserted into the body passageway42. In the unlock position, the button20is inserted further into the body passageway42than in the lock position.

The button cleat52extends from the button base front face68into the body cleat slide opening46. The button cleat52engages the cleat slide upper end48to prevent the base bottom64from sliding out of the passageway42through the body top16. Preferably, a second button cleat (not shown) extends from the base rear face, and extends into a cleat slide opening farmed in the body rear wall38.

An aperture72formed through the button base62from the front face68to the rear face is exposed when the button20is in the lock position. A pin member, such as a lock hasp, can be slipped through the aperture72to prevent the button20from being moved to the unlock position.

A cavity74formed in the base front face68receives the pair of leaf springs22which extend past the base bottom64. The leaf springs22engage stops76extending substantially perpendicular to the axis60. The stops76prevents the leaf springs22from slipping axially in the cavity74. Although a cavity74having stops76to prevent axial movement of the leaf springs22is shown, other methods for fixing the leaf springs22to the button20can be used, such as fanning a groove in the base front face to receive the leaf springs, embedding a proximal end of each leaf spring in the body, and the like, without departing from the scope of the present invention.

The leaf springs22are fixed to the button20, and extend through the body passageway42past the button base bottom18. Preferably, the leaf springs22are formed from high tension spring wire joined at one end to form a U-shaped member, wherein each leaf spring22is a leg of a U-shaped member. A distal end78of each leaf spring22extends out of the nose24slidably mounted in the passageway42.

A pin34is formed at each leaf spring distal end78, and extends substantially perpendicular to the axis60. The pins34engage the holes32formed in the switch tongue cavity walls28to prevent movement of the switch tongue26between the “On” and “Off” positions. In the embodiment shown inFIGS. 1-4, the leaf springs22are biased to move laterally inwardly away from the body side walls40, and the pins34extend outwardly in opposite directions for engagement with the inwardly opening holes32formed in the switch tongue cavity walls28.

The nose24channels the leaf spring22as the button20axially moves between the lock and unlock positions. The nose24extends out of the body passageway42through the body bottom18, and includes a front wall80and rear wall82joined by side walls84. The walls80,82,84define a passageway86extending from an open nose top88to a pair of openings90in a nose bottom92. A bottom wall94disposed between the openings90closes the nose bottom92. Although a single passageway86extending through the nose24is shown, separate passageways leading to each opening90for each leaf spring22can be used without departing from the scope of the present invention.

The nose24slidably engages the body walls80,82,84, and is dimensioned for slidable movement in the body passageway42. Slidable movement of the nose24into the passageway42is limited by the body side wall steps44which can engage the nose top88. Although slidably fixing the nose24in the body passageway42is preferred, the nose24can be rigidly fixed to the body14, or formed as an integral part of the body14without departing from the scope of the present invention.

As in the button20, the nose cleat54extends from the nose front wall80, and is received in the body cleat slide opening46. The nose cleat54engages the cleat slide lower end50to prevent the nose24from sliding out of the passageway42through the base bottom18. Preferably, a second nose cleat (not shown) extends from the nose rear wall82, and extends into the cleat slide opening formed in the body rear wall38. Although cleats52,54received in the cleat slide opening46are shown to limit axial movement of both the button20and nose24in the body passageway42, other methods known in the art for limiting slidable movement, such as steps formed in the body14, button20, and nose24, can be used without departing from the scope of the present invention.

The nose side walls84converge toward the axis60, such that the open top88is laterally wider than the bottom92. Bach bottom opening90is formed at the junction of one of the side walls84and the bottom wall94. Each leaf spring22extends through one of the openings90. As the leaf rigs22slidably move through the openings90to a lock position, the bottom wall94urges each leaf spring distal end78, and thus the pins34, outwardly to engage the switch tongue cavity holes32.

Preferably, a helical spring96interposed between the button20and nose24biases the button20toward the lock position. The spring96has one end98engaging the nose top88and an opposing end100engaging the button bottom64. Although a spring biasing the button toward the lock position is preferred, the lock-out assembly can be used with a biasing member biasing the button in the unlock position, and can be used without a biasing member biasing the button in any direction, without departing firm the scope of the invention.

In use, the user urges the button20toward the unlock position by depressing the button20which extends the leaf springs22through the nose bottom openings90. The extended leaf springs22are biased inwardly, such ta the pins34can be slipped between the switch tongue cavity walls28and aligned with the inwardly opening holes32. The user aligns the pins34with the holes32, and then releases the button20. When the button20is released, the helical spring96urges the button20to the lock position, and retracts the leaf springs22through the nose bottom openings90. As the leaf springs22retract, the nose bottom wall94forces the leaf springs22outwardly, such that the pins34are forced into the holes32. Once the pins34are received in the holes32, the user can slip a lock hasp through the button aperture72to prevent the button20from being depressed to disengage the lock-out assembly10from the circuit breaker12.

The process is reversed to disengage the lock-out assembly10from the circuit breaker12. Advantageously, the lock-out assembly10can be engaged and disengaged from the circuit breaker12using one hand by imply depressing and releasing the button20using a thumb while two fingers are wrapped around the body arms56to hold the lock-out assembly10.

In another embodiment shown inFIGS. 5-7, a lock-out assembly110engages outwardly opening holes126formed in the walls128adjacent a circuit breaker switch tongue130. In this embodiment, the leaf springs122are biased outwardly, and the pins134formed on the leaf spring distal ends178extend inwardly toward each other for engagement with the outwardly opening holes126. The nose bottom192in the alternate embodiment assembly110is open, and the side walls184of the nose124force the leaf springs122, and thus the pins134, inwardly when the button120moves from the unlock position to the lock position.