Claims:1. A device for a jaw cluster replacement from cradle terminal of circuit breakers, the said device comprising:
a first and a second essentially rigid elongated body members;
a fastening means for the said first and second body members;
a clamp for holding the jaw cluster;
a rivet to fasten the clamp;
wherein the first and second body members each have a jaw end, a handle end and an intermediate portion;
wherein the fastening means comprises a slot in the neck portion of the first body member and a pawl pivotably secured to the neck portion of the second body member and disposed to slide within the said slot;
wherein the fastening means permits the jaw ends to move toward each other in a sliding action in response to a manual force being applied to the handle ends;
wherein the rivet fixes the clamp on the jaw end of the first and second members; and
wherein the clamp mechanically pivots on jaw end of the first and second members.

2. The device as claimed in claim 1, wherein the clamp comprises two ends.

3. The device as claimed in claim 2, wherein the clamp is substantially rectangular or square in shape when the two ends are in contact with each other.

4. The device as claimed in claim 3, wherein the clamp completely encases the jaw cluster in its cavity when the handles are slid towards each other.

5. The device as claimed in claim 1, wherein the clamp comprises of grooves for gripping the jaw cluster.

6. The device as claimed in claim 1, wherein the handles are covered by an insulation sleeve.

7. The device as claimed in claim 6, wherein the insulation sleeve protects from high electric voltages.

8. The device as claimed in claim 6, wherein the insulation sleeve provides traction for gripping the device.

9. The device as claimed in claim 6, wherein the clamp ends separate as the handles are slid away from each other.

10. The device as claimed in claim 1, wherein the jaw cluster of circuit breaker is replaced in an electrically live condition.

11. The device as claimed in claim 1, wherein the jaw cluster is replaced from top or bottom or middle slots of a cradle terminal.

12. The device as claimed in claim 1, wherein the jaw cluster can be replaced from multiple directions.

13. The device as claimed in the claim 1, wherein the clamp prevents the jaw cluster to fall on electrically live parts of the circuit breaker in dust or humid conditions.
, Description:FIELD OF THE INVENTION

[001] The subject matter of the present invention, in general, relates to circuit breakers and particularly, pertains to a device for jaw cluster replacement of circuit breakers.

BACKGROUND OF INVENTION

[002] A circuit breaker is an automatically operated electrical switching device that protects electrical circuits from damage owing to excess flow of current typically resulting from an overload or short circuit. Its basic function is to interrupt current flow after a fault is detected. Unlike a fuse that operates only once and needs to be replaced when blown, a circuit breaker is a resettable device (either manually or automatically) to resume normal operation.

[003] There are varieties of circuit breakers available based on type, area of application etc. One such type of circuit breaker is the air circuit breakers that is usually used in low voltage applications. These are circuit breakers find application as the main circuit breaker for power distribution systems for buildings, factories, ships, etc. Importantly they are employed to realize high-level circuit monitoring and friendly networking. Its trip characteristics are often fully adjustable including configurable trip thresholds and delays. This type of circuit breaker is used to carry, make and break the flow of current in low-voltage applications. There are two type of air circuit breakers, viz., fixed type air circuit breaker and withdrawable (draw-out type) type.

[004] The draw-out circuit breaker has two parts, one is the base that is bolted and wired to the frame and the actual breaker and which slides into and electrically mates with the base thereby allowing the unit to be replaced without having to turn off the power feeding the breaker. The load must be turned off to test or remove the unit. In the draw-out type of air circuit breaker the moving switching module is the breaker while the fixed compartment is referred to as a cradle. Power supply is fed to cradle terminal of cradle compartment in draw out type of air circuit breaker. Breaker is a separable component and needs to be inserted into the cradle compartment during normal operating conditions to complete the electrical path. Also, it may be removed from cradle during maintenance or as and when the need arises.

[005] The fixed type of air circuit breakers comprises of housing-mounted fixed conductor and a moving conductor assembly that forms a part of the moving switching module. A cradle compartment comprises of a conducting jaw cluster and an intermediate connecting adaptor also known as the cradle terminal that connects the housing-mounted conductor also known as the breaker adaptor with jaw cluster. The jaw cluster is a flexible conducting device and mounted on housing-mounted conductor also known as the breaker adaptor and intermediate connecting adaptor also known as cradle terminal. The jaw cluster assembly comprises of one support element, conducting plates and spring. The supporting elements often referred as a jaw cage that holds the conducting plates also known as jaw fingers and the spring.

[006] Presently, the method of inserting and removing the jaw cluster from the cradle terminal is accomplished on makeshift basis and leads to a possibility of loose assembly of the jaw cluster in a cradle terminal that results in a loose connection between cradle terminal and housing-mounted conductor also known as the breaker adaptor which is neither a desirable condition or a desirable connection. Moreover, the jaw cluster is required to be removed and inserted on a regular basis for maintenance of the air circuit breaker, to clean the jaw cluster to ensure proper operation, to inspect for damaged jaw clusters and electrical deterioration of jaw clusters with usage.

[007] Significantly, a jaw cluster can be removed from the air circuit breaker only when the cradle terminal of cradle compartment is isolated from electrical connection. Removing the jaw cluster in an electrically live condition without proper device is a dangerous condition. Thus, to insert or remove the jaw cluster from the cradle terminal of cradle compartment requires total shut down of power distribution systems, which is undesirable and cumbersome.

[008] Therefore, there is a need for a handheld device that allows an operator to remove or insert the jaw cluster from the cradle terminal of a low voltage air circuit breaker in an electrically live condition to do away with the requirement of shutting down the power distribution of system completely.

SUMMARY OF THE INVENTION

[009] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[0010] An object of the present invention is to provide a handheld device for jaw cluster replacement of circuit breakers.

[0011] Another object of the present invention is to provide a device that aids in removing or inserting the jaw cluster from the cradle terminal of a circuit breaker in an electrically live condition.

[0012] Another object of the present invention is quick, easy and safe replacement of the jaw cluster from the cradle terminal of a circuit breaker without shutting down the power distribution system.

[0013] Another object of the present invention is a device for jaw cluster replacement of circuit breakers in live electrical condition that provides the operator with high voltage protection and proper grip during operation.

[0014] Another object of the present invention is the ability to replace jaw clusters situated at the top or middle or bottom slots of the cradle terminal.

[0015] Yet another object of the present invention is to provide a device with a clamp riveted on a plier that can be mechanically pivoted.

[0016] Yet another object of the present invention is to provide grooves on the clamp for proper gripping of the jaw cluster.

[0017] Yet another object of the present invention is to provide a cage like clamp that snugly holds the jaw cluster in its cavity.

[0018] Yet another object of the present invention is to provide an insulation sleeve on handle of the plier that provides high voltage protection and aids in proper gripping of the device by the operator during operation.

[0019] Briefly, a handheld device to manually replace a jaw cluster from a cradle terminal of a circuit breaker in an electrically live condition by an operator is disclosed. The device comprises of a clamp riveted on a plier that can be mechanically pivoted and has an insulation sleeve on the handles of the plier for protection and proper griping of the device when used in high voltage conditions. The clamp is shaped like a cage like structure so that the jaw cluster is snugly held within the cavity of the clamp and grooves on the clamp provides proper gripping of the jaw cluster by the clamp. The clamp design ensures that the jaw cluster does not slip and fall on live parts.

[0020] The present invention discloses a device for jaw cluster replacement of circuit breakers, the said device comprising of a first and a second essentially rigid elongated body members, a fastening means to secure the first and second body members together, a clamp for holding the jaw cluster, and a rivet to fasten the clamp. The first and second body members each have a jaw end, a handle end and an intermediate portion and secured together by the fastening means that comprises a slot in the neck portion of the first body member and a pawl pivotably secured to the neck portion of the second body member and disposed to slide within the said slot. The fastening means permits the jaw ends to move toward or away from each other in a sliding action in response to the direction of manual force being applied to the handle. The rivet fixes the clamp on the jaw end of the first and second members and enables the clamp to mechanically pivot on the jaw ends of the first and second members.

[0021] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

[0022] The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0023] Figure 1 illustrates the device for removing the jaw cluster from the circuit breaker according to one implementation of the present invention.

[0024] Figure 2 illustrates a cluster jaw assembly of a conventional low voltage air circuit breaker.

[0025] Figure 3 illustrates the cradle terminal of a conventional low voltage air circuit breaker.

[0026] Figure 4 illustrates the jaw cluster insertion procedure according to one implementation of the present invention.

[0027] Figure 5 illustrates the jaw cluster removal procedure according to one implementation of the present invention.

[0028] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0029] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0030] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0031] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0032] It is to be understood that the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise.

[0033] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0034] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0035] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or component but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0036] The subject invention lies in providing a device for replacing a jaw cluster from a cradle terminal of a circuit breaker in an electrically live condition.

[0037] In the present invention, a handheld device to be operated by an operator to manually replace a jaw cluster from the cradle terminal of a circuit breaker in an electrically live condition is disclosed. The device comprises of a clamp riveted on a plier that can be mechanically pivoted. It has an insulation sleeve on the handles of the plier for protecting the operator from high voltage and also aids in proper griping of the device. The cage like clamp snugly holds the jaw cluster within its cavity and the grooves on the clamp provides traction for proper gripping of the jaw cluster by the clamp thereby avoiding the jaw cluster falling onto live parts.

[0038] In one implementation, a handheld device for manual replacement of a jaw cluster of circuit breakers is provided for.

[0039] In one implementation, a device that aids in removing or inserting the jaw cluster from the cradle terminal of a circuit breaker in an electrically live condition is provided for.

[0040] In one implementation, quick, easy and safe replacement of the jaw cluster from the cradle terminal of a circuit breaker without shutting down the power distribution system is provided for.

[0041] In one implementation, a device for jaw cluster replacement of circuit breakers in live electrical condition that provides the operator with high voltage protection and proper gripping is provided for.

[0042] In one implementation, is the ability to replace jaw clusters situated at the top or middle or bottom slots of the cradle terminal is provided for.

[0043] In another implementation, a device with a clamp riveted on a plier that can be mechanically pivoted is provided for.

[0044] In another implementation, grooves on the clamp for proper gripping of the jaw cluster is provided for.

[0045] In another implementation, the cage like clamp snugly holds the jaw cluster in the cavity of the clamp is provided for.

[0046] In another implementation, an insulation sleeve on handle of the plier for high voltage protection and proper gripping of the device by the operator during operation is provided for.

[0047] Figure 1 illustrates the device for replacing the jaw cluster of a circuit breaker. The device (11) comprises of a clamp (1, 2), a plier (3), a rivet (4) for fixing the clamp (1, 2) on plier (3) and an insulation sleeve (5) on handles. The clamp has two ends (1) and (2) that substantially resembles a rectangle or a square when in contact with each other. The handles, when brought towards each other close the clamp ends and when moved away from each other opens the clamp ends. The plier (3) comprises of a first and second rigid elongated body members, with each member have a jaw portion, a neck portion and handle portion, that are secured together with a fastening means involving a slot in the neck portion of the first body member and a pawl pivotably secured to the neck portion of the second body member and disposed to slide within the said slot thereby allowing the jaw ends of the device to move towards or away from each other in a sliding action when manual force is applied to the handle ends.

[0048] Figure 2 illustrates a jaw cluster assembly (12) that comprises of a support element or jaw cage (6), conducting plates or jaw finger (8) and springs (7). The jaw cage (6) holds the jaw fingers (8) and spring (7). The jaw cluster assembly (12) is held by the device (11) with the help clamp (1, 2) which is riveted (4) to the plier (3).

[0049] Figure 3 illustrates the cradle terminal (10) that has a slot (9) to engage the jaw cluster (12). The device (11) grips the jaw cluster assembly (12) that is housed within the cradle terminal (10) with the clamp (1, 2). The operator holds the insulation sleeve (5) on the handles to operate the device (11).

[0050] Figure 4 illustrates the procedure to insert a jaw cluster (12) in cradle terminal (10) of cradle compartment. It involves holding the jaw cluster (12) to be inserted in cradle terminal (10) of the cradle compartment with the clamp (1, 2) of the device (11), aligning the supporting part or jaw cage (6) of the jaw cluster (12) in the cradle terminal’s (10) slot (9), and holding the jaw cluster assembly (12) and pushing it inside cradle terminal (10). The operator needs to ensure that jaw cluster assembly (12) properly rests in cradle terminal (10) slot (9) of cradle compartment.

[0051] Figure 5 illustrates the procedure to remove a jaw cluster assembly (12) from the cradle terminal (10) of cradle compartment. It involves holding the jaw cluster (12) to be removed from the cradle terminal (10) of cradle compartment with the clamp (1, 2) of the device (11), holding and tilting the jaw cluster assembly (12) in suitable direction (it may be left or right right) with the device (11), and pulling the jaw cluster (12) snugly held by the clamps (1, 2) of the device (11) towards the operator.

[0052] Conventionally, a jaw cluster is removed from the cradle compartment of a low voltage air circuit breaker only when the cradle terminal of cradle compartment is isolated from electrical connection as there are no dedicated tools available for removing the jaw cluster in an electrically live condition. Trying to remove such jaw clusters without a proper device in an electrically live condition can be dangerous and sometimes near fatal for the operator. Thus, to insert or remove the jaw cluster from the cradle terminal of cradle compartment requires that the power distribution system is completely shut down, which is undesirable and cumbersome because jaw clusters need to be removed and inserted on a regular basis for cleaning and maintenance of the air circuit breaker, to inspect for damages and electrical deterioration of jaw clusters with passage of time.

[0053] Therefore, there is a need for a handheld device that allows the operator to remove or insert a jaw cluster from the cradle terminal of a low voltage air circuit breaker in an electrically live condition to do away with the requirement of shutting down the power distribution of system completely.

[0054] The present invention discloses a device with an insulated handle that makes the task of jaw cluster replacement possible in live condition of electric supply. It comprises of a first and a second rigid elongated body members, a fastening means for securing the first and second body members together, a clamp for holding the jaw cluster, and a rivet to fasten the clamp. The first and second body members each have a jaw end, a handle end and an intermediate portion. The fastening means comprises a slot in the neck portion of the first body member and a pawl pivotably secured to the neck portion of the second body member and disposed to slide within the said slot. It is the fastening means that permit the jaw ends of the device to move toward each other in a sliding action when manual force is applied to the handle ends to bring them closer to each other and vice-versa. The rivet fixes the clamp on the jaw end of the first and second members and enables the clamp to mechanically pivot.

[0055] Although a simple, economic and cost effective device for replacing the jaw cluster within the cradle compartment of a low voltage air circuit breaker been described in language specific to structural features indicated, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or devices described therein. Rather, the specific features are disclosed as examples of implementations of the device for removing or inserting a jaw cluster of a circuit breaker.