Description:TECHNICAL FIELD
[0001] The present disclosure relates, in general, to molded case circuit breaker, and more specifically, relates to compensating the overtravel provided for resetting the trip unit of a circuit breaker.

BACKGROUND
[0002] Circuit Breaker is a mechanical switching device capable of making, carrying, and breaking currents. Under normal circuit conditions, it may make the circuit, carry current for a specified time, and break the circuit under specified abnormal circuit conditions. Circuit Breakers are employed for the current interruption. More particularly, circuit breakers are utilized to protect instruments from damage during adverse conditions prevailing during the operation of the circuit in which the circuit breaker is employed. During adverse conditions like a short circuit, the current rises to an alarmingly high level. This high current may cause damage to the parts in the electrical system. Hence during these conditions, the circuit must be opened to protect the system.
[0003] When release senses abnormal conditions, it gives the trip command to the mechanism so that the latter opens the circuit. This tripping mechanism happens when release, through its tripping medium like flux shift device (FSD), under-voltage (UV) or shunt de-latches and applies a force greater than the trip force on the trip plate of the operating mechanism. Once the circuit breaker has tripped, it needs to be reset prior to subsequent ON operation. This is done through the operating handle and operating mechanism of the circuit breaker. During this reset operation of the circuit breaker, the de-latched release tripping medium like FSD, UV or shunt also gets reset through cam arrangement. To ensure the resetting of tripping mediums, additional travel known as overtravel is built into the system. This overtravel if not managed/compensated effectively may either not reset the tripping mediums and/or stress and damage the components of the tripping medium or operating mechanism.
[0004] An example of such circuit breaker is recited in a patent that talks about an arrangement of using elastic properties of a molded material to compensate for overtravel. Post-reset of the trip unit the excess travel is absorbed through the elastic deformation of a molded component used to reset it. This arrangement works fine for absorbing a low amount of overtravel and/or low forces due to overtravel. However, for higher travel/forces the risk of plastic deformation and thereby permanent damage increases substantially. Also, for robust and reliable working throughout the life of the product, depending on elastic deformation can be detrimental.
[0005] Therefore, it is desired to overcome the drawbacks, shortcomings, and limitations associated with existing solutions, and develop an arrangement for absorbing excess overtravel in a tripping mechanism using a calibrated spring arrangement. This allows for reliable resetting of the tripping mediums while minimizing stress on the components. The spring arrangement is designed to transfer the complete travel of the operating handle to reset the tripping mediums while absorbing only the excess travel after the completion of resetting. Overall, this arrangement provides a more efficient and effective way to reset the tripping mechanism.

OBJECTS OF THE PRESENT DISCLOSURE
[0006] An object of the present disclosure relates, to molded case circuit breaker, and more specifically, relates to compensating the overtravel provided for resetting the trip unit of a circuit breaker.
[0007] Another object of the present disclosure is to provide a mechanism for absorbing excess overtravel in a tripping mechanism using a calibrated spring arrangement.
[0008] Another object of the present disclosure is to provide a mechanism that allows for reliable resetting of the tripping mediums while minimizing stress on the components.
[0009] Another object of the present disclosure is to provide a mechanism to transfer the complete travel of the operating handle to reset the tripping mediums while absorbing only the excess travel after the completion of resetting.
[0010] Yet another object of the present disclosure is to provide a mechanism that provides a more efficient and effective way to reset the tripping mechanism.

SUMMARY
[0011] The present disclosure relates in general, to molded case circuit breaker, and more specifically, relates to compensating the overtravel provided for resetting the trip unit of a circuit breaker. The main objective of the present disclosure is to overcome the drawback, limitations, and shortcomings of the existing arrangement and solution, by providing a mechanism to absorb excess overtravel in order to reliably reset tripping mediums. A spring arrangement is calibrated to transfer the complete travel of the operating handle for resetting, while also absorbing only the excess travel beyond that point. This ensures that the resetting process is reliable and minimizes stress on the components involved.
[0012] In an aspect, the mechanism can include a tripping medium configured in chassis adapted to trip the MCCB, upon occurrence of fault. The operating handle of the operating mechanism is movable between a trip state and a reset state. An actuator of the tripping medium is movable between a first position and a second position to decompress and compress a spring arrangement so as to de-latch and latch the operating mechanism of the MCCB. At the first position, the actuator decompresses the spring arrangement for de-latching the operating mechanism of the MCCB. At the second position, the actuator compresses the spring arrangement and eventually latches onto the protruded feature of the chassis. Further, at the trip state of the MCCB, the actuator of the tripping medium is movable to decompress the spring arrangement so as to de-latch the operating mechanism of the MCCB and at the reset state of the MCCB, the actuator of the tripping medium movable to compress the spring arrangement so as to latch the operating mechanism of the MCCB.
[0013] In another aspect, the plate is pivotally coupled to the operating handle and rotated in a clockwise and counterclockwise direction to perform the reset operation. At the reset operation of the MCCB, the operating handle is rotated clockwise, which pushes the actuator rightward compressing the spring arrangement via a pin riveted to the plate and causing the plate to rotate clockwise latching the actuator of the tripping medium, and wherein at the latched state, the actuator is stopped to exceed the travel limit of the operating handle so as to prevent causing damage to the tripping medium.
[0014] The plate is pivotally coupled to the operating handle by a screw and biased in the counterclockwise direction by a torsion spring. The counterclockwise rotation of the plate is restricted by a bend feature that rests on the thickness profile of the operating handle such that excess force and travel do not get passed on to the tripping medium preventing it from getting damaged. At the latched state, the actuator of the tripping medium is stopped on the protruded feature of the chassis to prevent the remaining travel of the operating handle to reset the operating mechanism, from damaging the tripping medium. The pin generates a clockwise torque on the plate, which is higher than the counterclockwise torque of the torsion spring when the operating handle is rotated beyond the latching point. Further, the plate rotates in the clockwise direction absorbing the excess travel of the operating handle and preventing excess force from reaching the tripping medium thus avoiding damage.
[0015] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.
[0017] FIG. 1 illustrates the simplified representation of MCCB in the trip state, in accordance with an embodiment of the present disclosure.
[0018] FIG. 2 illustrates an exemplary simplified representation of MCCB in an intermediate position between trip & reset, in accordance with an embodiment of the present disclosure.
[0019] FIG. 3 illustrates an exemplary simplified representation of MCCB in the reset state, in accordance with an embodiment of the present disclosure.
[0020] FIG. 4A to FIG. 4B illustrate exemplary simplified representation of the MCCB operating mechanism in trip state and in reset state, in accordance with an embodiment of the present disclosure
[0021] FIG. 5A to FIG. 5B illustrate exemplary simplified representation of the MCCB tripping medium in a de-latched state and in latched state, in accordance with an embodiment of the present disclosure.
[0022] FIG. 6 illustrates an exemplary exploded view showing an assembly sequence of spring plate arrangement, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0023] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0024] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0025] The present disclosure relates to molded case circuit breaker, and more specifically, relates to compensating the overtravel provided for resetting the trip unit of a circuit breaker. The proposed mechanism disclosed in the present disclosure overcomes the drawbacks, shortcomings, and limitations associated with the conventional arrangement by providing an overtravel compensating mechanism for resetting a molded case circuit breaker (MCCB). The excess overtravel is absorbed by a spring arrangement. This arrangement is calibrated to transfer complete travel of the operating handle to reset the tripping mediums and absorb only the excess travel post-completion of resetting of tripping mediums. This ensures reliable resetting in terms of travel as well as stress on the components
[0026] In an aspect, the mechanism can include a tripping medium configured in chassis adapted to trip the MCCB, upon occurrence of fault. The operating handle of the operating mechanism is movable between a trip state and a reset state. An actuator of the tripping medium is movable between a first position and a second position to decompress and compress a spring arrangement so as to de-latch and latch the operating mechanism of the MCCB. At the first position, the actuator decompresses the spring arrangement for de-latching the operating mechanism of the MCCB. At the trip state of the MCCB, the actuator of the tripping medium is movable to decompress the spring arrangement so as to de-latch the operating mechanism of the MCCB. At the second position, the actuator compresses the spring arrangement and eventually latches onto the protruded feature of the chassis. At the reset state of the MCCB, the actuator of the tripping medium is movable to compress the spring arrangement so as to latch the operating mechanism of the MCCB.
[0027] In another aspect, the plate is pivotally coupled to the operating handle and rotated in clockwise and counterclockwise direction to perform the reset operation. At the reset operation of the MCCB, the operating handle is rotated clockwise, which pushes the actuator rightward compressing the spring arrangement via a pin riveted to the plate and causing the plate to rotate clockwise latching the actuator of the tripping medium, and wherein at the latched state, the actuator is stopped to exceed the travel limit of the operating handle so as to prevent causing damage to the tripping medium.
[0028] The plate is pivotally coupled to the operating handle by a screw and biased in the counterclockwise direction by a torsion spring. The counterclockwise rotation of the plate is restricted by a bend feature that rests on the thickness profile of the operating handle such that excess force and travel do not get passed on to the tripping medium preventing from getting damaged. At the latched state, the actuator of the tripping medium is stopped on the protruded feature of the chassis to prevent the remaining travel of the operating handle to reset the operating mechanism, from damaging the tripping medium. The pin generates a clockwise torque on the plate, which is higher than the counterclockwise torque of the torsion spring when the operating handle is rotated beyond the latching point. Further, the plate rotates in the clockwise direction absorbing the excess travel of the operating handle and preventing excess force from reaching the tripping medium thus avoiding damage. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.
[0029] The advantages achieved by the mechanism of the present disclosure can be clear from the embodiments provided herein. The mechanism for absorbing excess overtravel in a tripping mechanism using a calibrated spring arrangement. This allows for reliable resetting of the tripping mediums while minimizing stress on the components. The spring arrangement is designed to transfer the complete travel of the operating handle to reset the tripping mediums while absorbing only the excess travel after the completion of resetting. Overall, this arrangement provides a more efficient and effective way to reset the tripping mechanism. The description of terms and features related to the present disclosure shall be clear from the embodiments that are illustrated and described; however, the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents of the embodiments are possible within the scope of the present disclosure. Additionally, the invention can include other embodiments that are within the scope of the claims but are not described in detail with respect to the following description.
[0030] FIG. 1 illustrates the simplified representation of MCCB in trip state, in accordance with an embodiment of the present disclosure.
[0031] Referring to FIG. 1, overtravel compensating mechanism 100 for resetting the trip unit of circuit breaker is disclosed. The overtravel compensating mechanism 100 can include tripping medium 102, an operating mechanism 104 shown in FIG.4A, an actuator 106, a spring 108, a plate 110, a pin 112, a pivot screw 114, a torsion spring 116 and a operating handle 118.
[0032] As depicted in FIG. 1, the MCCB is in the trip state and the operating mechanism 104 is de-latched and operating handle 118 is in the trip position and the tripping medium 102 is also in the de-latched state. The tripping medium 102 can include a chassis, where the tripping medium 102 is adapted to trip the MCCB, upon occurrence of fault. The operating handle 118 of operating mechanism 104 is configured in the chassis and movable between a first state and a second state. In an exemplary embodiment, the first state as present in the example is the trip state and the second state as present in the example is the reset state.
[0033] The tripping medium 102 is configured for tripping the circuit breaker by de-latching the operating mechanism 104 through the actuator 106. The tripping medium 102 can include the actuator 106 and the spring arrangement 108 which is designed to trip the MCCB by de-latching the operating mechanism 104 when a fault occurs. Once the MCCB is tripped, the operating handle 118 is in the trip state and needs to be reset before the subsequent ON operation.
[0034] The actuator 106 is a component of the tripping medium 102, the actuator 106 is movable between a first position and a second position to decompress and compress the spring arrangement 108 so as to de-latch and latch the operating mechanism 104 of the MCCB. The actuator 106 at the first position decompresses the spring arrangement 108 for de-latching the operating mechanism 104 of the MCCB, which triggers the trip state. During the reset operation, as the operating handle 118 is pushed in a clockwise direction, the actuator 106 is pushed rightward by pin 112 riveted to the plate 110. The actuator 106 at the second position compresses the spring arrangement 108 and eventually latches onto a protruded feature of the chassis triggering the reset state to prevent excess force and travel from damaging the tripping medium 102.
[0035] The reset mechanism can include plate 110 which is pivoted to the operating handle 118 of the MCCB by means of the screw 114. The plate 110 is forcibly biased in the counterclockwise direction by the torsion spring 116. The counterclockwise rotation of the plate 110 is restricted by a bend feature on the plate 110 resting on the thickness profile of the operating handle 118.
[0036] The plate 110 is a pivotal component of the operating mechanism 104 of the MCCB, which is designed to reset after tripping due to the action of the tripping medium 102. The plate 110 is pivotally coupled to the operating handle 118 by the screw 114 and biased in the counterclockwise direction by the torsion spring 116. The purpose of this design is to ensure that excess force and travel do not get passed on to the tripping medium, preventing it from getting damaged.
[0037] For example, during the reset operation, the operating handle 118 is pushed in the clockwise direction to initiate the reset operation of the MCCB. As the operating handle 118 travels clockwise, the actuator 106 of the tripping medium 102 also gets pushed rightward, compressing the spring 108, by means of the pin 112 riveted to the plate 110. The plate 110 rotates counterclockwise, delivering a counterclockwise torque slightly higher than the maximum clockwise torque that plate 110 may experience through pin 112 as it pushes the actuator 106 of the tripping medium 102 to its latched position.
[0038] The value of force to compute maximum clockwise torque on plate 110 is the force delivered by the spring 108 at the latched position of tripping medium 102. The counterclockwise rotation of plate 110 is restricted by means of a bend feature on plate 110 resting on the thickness profile of the operating handle 118. Once the tripping medium 102 is latched, the actuator 106 of the tripping medium 102 is stopped on a protruded feature of the chassis to prevent the remaining travel of operating handle 118 to reset the operating mechanism 104, from damaging the tripping medium 102.
[0039] If the operating handle 118 is further rotated, pin 112 experiences a drastically higher force that generates a clockwise torque on plate 110 that is higher than the counterclockwise torque delivered by the torsion spring 116. This causes plate 110 to rotate in the clockwise direction and absorb the excess travel of the operating handle 118, thus preventing any excess force from being passed on to the tripping medium 102 and preventing damage.
[0040] The spring 116 and plate arrangement 110, along with the stopper on the chassis, ensure that the tripping medium 102 is protected from damage during the reset operation. The present invention provides a reliable and efficient mechanism for resetting MCCBs after they have tripped, thus ensuring the proper functioning of the electrical system.
[0041] Thus, the present invention overcomes the drawbacks, shortcomings, and limitations associated with existing solutions, and provides an arrangement for absorbing excess overtravel in a tripping mechanism using a calibrated spring arrangement. The arrangement allows for reliable resetting of the tripping mediums while minimizing stress on the components. The arrangement to transfer the complete travel of the operating handle to reset the tripping mediums, while absorbing only the excess travel after the completion of resetting and provides a more efficient and effective way to reset the tripping mechanism.
[0042] FIG. 2 illustrates an exemplary simplified representation of MCCB in an intermediate position between trip and reset, in accordance with an embodiment of the present disclosure. The operating mechanism 104 is still not latched and operating handle 118 is being pushed to reset from earlier trip position. This travel of operating handle 118 has now reset the tripping medium 102 which is now latched.
[0043] FIG. 3 illustrates an exemplary simplified representation of MCCB in the reset state, in accordance with an embodiment of the present disclosure. The operating mechanism 104 is latched, and operating handle 118 is in a reset position. The tripping medium 102 had latched earlier, and the excess travel of operating handle 118 is absorbed by the spring plate arrangement.
[0044] FIG. 4A to FIG. 4B illustrate exemplary simplified representation of the MCCB operating mechanism in trip state and reset state, in accordance with an embodiment of the present disclosure. FIG. 4A depicts the simplified representation of MCCB operating mechanism in trip state. The tripping medium 102 configured in chassis adapted to trip the MCCB, upon occurrence of fault. The operating handle 118 of operating mechanism 104 is movable to the trip state. FIG. 4B depicts the simplified representation of the MCCB operating mechanism in the reset state.
[0045] FIG. 5A to FIG. 5B illustrate exemplary simplified representation of the MCCB tripping medium in de-latched state and latched state, in accordance with an embodiment of the present disclosure. FIG. 5A depicts and simplified representation of MCCB tripping medium 102 in de-latched state at trip position and FIG. 5B depicts and simplified representation of MCCB tripping medium in latched state at reset position.
[0046] FIG. 6 illustrates an exemplary exploded view showing an assembly sequence of spring plate arrangement, in accordance with an embodiment of the present disclosure. The spring 116 and plate arrangement 110, along with the stopper on the chassis, ensure that the tripping medium 102 is protected from damage during the reset operation. The present invention provides a reliable and efficient mechanism for resetting MCCBs after they have tripped, thus ensuring the proper functioning of the electrical system.
[0047] It will be apparent to those skilled in the art that the mechanism 100 of the disclosure may be provided using some or all of the mentioned features and components without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF THE PRESENT INVENTION
[0048] The present invention provides a mechanism for absorbing excess overtravel in a tripping mechanism using a calibrated spring arrangement.
[0049] The present invention provides a mechanism that allows for reliable resetting of the tripping mediums while minimizing stress on the components.
[0050] The present invention provides a mechanism to transfer the complete travel of the operating handle to reset the tripping mediums while absorbing only the excess travel after the completion of resetting.
[0051] The present invention provides a mechanism that provides a more efficient and effective way to reset the tripping mechanism.

, Claims:1. An overtravel compensating mechanism (100) for resetting a molded case circuit breaker (MCCB), the mechanism comprising:
a tripping medium (102) configured in chassis adapted to trip the MCCB, upon occurrence of fault;
an operating handle (118) of operating mechanism (104) movable between a trip state and reset state;
an actuator (106) of the tripping medium (102) movable between a first position and a second position to decompress and compress a spring arrangement (108) so as to de-latch and latch the operating mechanism (104) of the MCCB; and
a plate (110) is pivotally coupled to the operating handle and rotated in clockwise and counterclockwise direction to perform reset operation, wherein at the reset operation of the MCCB, the operating handle (118) is rotated clockwise, which pushes the actuator (106) rightward compressing the spring arrangement (108) via a pin (112) riveted to the plate (110) and causing the plate (110) to rotate clockwise latching the actuator (106) of the tripping medium (102), and wherein at the latched state, the actuator (106) is stopped to exceed the travel limit of the operating handle (118) so as to prevent causing damage to the tripping medium (102).
2. The mechanism as claimed in claim 1, wherein at the first position, the actuator (106) decompresses the spring arrangement (108) for de-latching the operating mechanism (104) of the MCCB.
3. The mechanism as claimed in claim 1, wherein at the second position, the actuator (106) compresses the spring arrangement (108) and eventually latches onto the protruded feature of the chassis.
4. The mechanism as claimed in claim 1, wherein at the trip state of the MCCB, the actuator (106) of the tripping medium (102) is movable to decompress the spring arrangement (108) so as to de-latch the operating mechanism (104) of the MCCB.
5. The mechanism as claimed in claim 1, wherein at the reset state of the MCCB, the actuator (106) of the tripping medium (102) is movable to compress the spring arrangement (108) so as to latch the operating mechanism (104) of the MCCB.
6. The mechanism as claimed in claim 1, wherein the plate (110) is pivotally coupled to the operating handle (118) by a screw (114) and biased in the counterclockwise direction by a torsion spring (116).
7. The mechanism as claimed in claim 1, wherein the counterclockwise rotation of the plate (110) is restricted by a bend feature that rests on the thickness profile of the operating handle (118) such that excess force and travel do not get passed on to the tripping medium preventing from getting damaged.
8. The mechanism as claimed in claim 1, wherein at the latched state, the actuator 106 of the tripping medium (102) is stopped on the protruded feature of the chassis to prevent the remaining travel of the operating handle (118) to reset the operating mechanism (104), from damaging the tripping medium (102).
9. The mechanism as claimed in claim 1, wherein the pin (112) generates a clockwise torque on the plate (110), which is higher than the counterclockwise torque of the torsion spring (116), when the operating handle (118) is rotated beyond the latching point.
10. The mechanism as claimed in claim 9, wherein the plate (110) rotates in the clockwise direction absorbing the excess travel of the operating handle (118) and preventing excess force from reaching the tripping medium (102) thus avoiding damage.