Claims:1. A cradle (1) of a circuit breaker, said cradle (1) operatively coupled with a motorized racking mechanism (23) and comprising:
a base plate (2);
a motor (3) configured on the base plate (2); and
a gearbox (28), wherein the gearbox (28) has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out.
2. The cradle (1) of claim 1, wherein when supply is given to the motor (3), the motor (3) rotates and transmits power to the gearbox (28) to enable stages of speed reduction and sufficient torque to the provided to rack (18), wherein the rack (18) connects the gearbox (28) with racking screw (20).
3. The cradle (1) of claim 1, wherein the motor (3) is fixed on the base plate (2) by a holding bracket (4).
4. The cradle (1) of claim 1, wherein the motor (3) is mounted on side plate (24), and wherein a motor pinion (6) is mounted on the motor (3) such that when supply is given to the motor (3), the pinion (6) that is engaged with a helical gear (7) starts rotating.
5. The cradle (1) of claim 4, wherein the helical gear (7) is compounded with worm (8), wherein by rotation of the worm (8), worm wheel (9) mounted on a worm wheel shaft (10) starts rotating.
6. The cradle (1) of claim 5, wherein a spur gear (29) mounted on the worm wheel shaft (10) gets engaged with spur gear (13) that is mounted on spur gear shaft (11), and wherein bevel gear (14) that is also mounted on the spur gear shaft (11) rotates along with the spur gear (13).
7. The cradle (1) of claim 6, wherein the spur gear shaft (11) has bearings (26) mounted on top cover (9) and bottom plate (25) such that with rotation of the bevel gear (14), bevel pinion (15) that is mounted on racking pinion shaft (12) rotates, and wherein racking pinion (16) is compounded with the bevel pinion (15), and wherein the racking pinion shaft (12) is supported with a shaft support (27) to enable motion to be transferred from motor rotation to racking pinion rotation with sufficient speed reduction and increased torque.
8. The cradle (1) of claim 1, wherein rack (18) is operatively coupled with a racking pinion (16) of the gearbox (28) such that with rotation of the racking pinion (16), the rack (18) converts rotational motion to translational and rotates racking screw pinion (17) mounted on racking screw (20) such that the racking operation takes place with the rotation of the racking screw (20).
9. The cradle (1) of claim 8, wherein travel of the rack (18) is guided by two rack guides (22), and wherein the racking screw (20) is mounted on support bracket (21).
10. The cradle (1) of claim 1, wherein direction of the motor (3) is reversed for performing racking out operation.

11. A circuit breaker operatively coupled with a cradle (1), said cradle (1) operatively coupled with a motorized racking mechanism (23) and comprising:
a base plate (2);
a motor (3) configured on the base plate (2); and
a gearbox (28), wherein the gearbox (28) has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out. , Description:TECHNICAL FIELD
[0001] The present disclosure relates generally to the field of circuit breakers. In particular, the present disclosure pertains to a system and method for motorized racking mechanism for draw-out type circuit breakers.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Circuit breakers are electrical devices that are installed in electrical circuits to allow connection and disconnection of the circuits from power source. Circuit breakers are commonly known as interrupters that open and close to stop and start flow of electrical current to the electrical circuits.
[0004] Switchgear systems can be either fixed to busbar systems, or can be removable type known as draw-out circuit breakers with an enclosure cradle arrangement provided for establishing and removing connection with the bus bar system.As per international standards, depending upon construction, air circuit breakers are classified as fixed and draw-out type circuit breakers. Draw-out type circuit breakers comprise two major parts, cradle and breaker. Cradle is the fixed part and breaker is the moving part, wherein inside the cradle, there is an arrangement to put the circuit breaker, and move it in and out to achieve different positions such as isolated, test, and service. Cradle consists of a racking mechanism and a rail system along with locking system and contact system.
[0005] Racking mechanism in existing breakers consists of rack and pinion arrangement for inserting the circuit breakers in the cradle. Racking operation is done manually by using a racking handle, which requires high force to be applied at the interface level to completely rack-in and rack-out the breaker. If there is high racking torque issue, it becomes very difficult to rack-in the breaker manually. High racking force leads to incomplete racking operation and thus breaker cannot be closed.
[0006] There is therefore a need for an improved racking mechanism that eliminates human intervention in all three positions, viz., isolated, test and service, and provides a smooth and hassle-free racking operation.
[0007] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0008] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about”. Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0009] 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.
[0010] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0011] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

OBJECTS OF THE INVENTION
[0012] An object of the present disclosure is to provide a system and method for motorized racking mechanism for draw-out type air circuit breakers.
[0013] An object of the present disclosure is to provide a cradle of a circuit breaker that has a motor and gearbox for racking operation of circuit breaker.
[0014] An object of the present disclosure is to provide a cradle that uses a rack and pinion arrangement for rotating racking screw to perform the racking operation.
[0015] An object of the present disclosure is to provide a cradle that provides sufficient torque for racking the breaker and reducing manual efforts.

SUMMARY
[0016] Aspects of the present disclosure relate to a motorized racking mechanism for draw-out type air circuit breakers. In an aspect, the proposed motorized racking mechanism has a motor and a gearbox for racking one or more air circuit breakers, wherein the gearbox can use gears such as a worm and a worm wheel, a bevel, a rack and pinion for controlling speed in order to get a desired speed reduction and generate a precise torque. Final rotation of the screw can be done with the help of the rack and pinion arrangement. The horizontally arranged gear can be housed as a kit and mounted on the base plate of a cradle. A micro switch can be used for supply cut off to the motor. Direction of the motor can be reversed through a rotation circuit that controls the direction of the motor.
[0017] In an aspect, the motorized racking mechanism includes a motor and a gearbox assembled on the base plate of a cradle, wherein the gearbox has a specific gear arrangement with suitable gear ratios for controlling the speed and generating a torque sufficient for racking operations. When the power is switched on, the motor can start rotating, transmitting power to the gearbox. Various gears of specific ratios can control the rotational speed at various stages resulting in a desired speed reduction at the end that can generate the required torque to a rack that can be engaged to the two pinions, one on the gearbox shaft and the other fixed on the racking screw, for final rotation of racking screw for the racking operation to take place.
[0018] In an aspect, direction of motor can be reversed through a rotation circuit controlling the direction of the motor for racking out of breaker.
[0019] In an aspect, the proposed motorized racking mechanism eliminates human efforts of racking the breaker manually as it presents a motorized racking mechanism for racking the breaker in all three positions, i.e., isolated, test and service. The motorized racking mechanism generates a torque sufficient to perform racking operation on Air Circuit Breakers in a smooth and hassle-free manner, taking care of excess torque, if any. The breaker can be easily moved from service position to maintenance position.
[0020] The proposed disclosure relates to a cradle of a circuit breaker, wherein the cradle is operatively coupled with a motorized racking mechanism, and comprises a base plate; a motor configured on the base plate; and a gearbox, wherein the gearbox has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out.
[0021] In an aspect, when supply is given to the motor, the motor rotates and transmits power to the gearbox to enable stages of speed reduction and sufficient torque to the provided to rack, wherein the rack connects the gearbox with racking screw. The motor can be fixed on the base plate by a holding bracket.
[0022] In another aspect, the motor can be mounted on side plate, wherein a motor pinion can be mounted on the motor such that when supply is given to the motor, the pinion that is engaged with a helical gear starts rotating. In an aspect, the helical gear can be compounded with worm, wherein by rotation of the worm, worm wheel mounted on a worm wheel shaft starts rotating. A spur gear that is mounted on the worm wheel shaft can get engaged with a second spur gear that is mounted on a spur gear shaft, wherein bevel gear that is also mounted on the spur gear shaft rotates along with the spur gear. In an aspect, the spur gear shaft has bearings mounted on top cover and bottom plate such that with rotation of the bevel gear, bevel pinion that is mounted on racking pinion shaft rotates, and wherein racking pinion is compounded with the bevel pinion, and wherein the racking pinion shaft is supported with a shaft support to enable motion to be transferred from motor rotation to racking pinion rotation with sufficient speed reduction and increased torque.
[0023] In an aspect, rack can be operatively coupled with a racking pinion of the gearbox such that with rotation of the racking pinion, the rack converts rotational motion to translational and rotates racking screw pinion mounted on racking screw such that the racking operation takes place with the rotation of the racking screw. In an aspect, travel of the rack can be guided by two rack guides, wherein the racking screw can be mounted on support bracket.
[0024] In an aspect, direction of the motor can be reversed for performing racking out operation.
The present disclosure further relates to a circuit breaker that is operatively coupled with a cradle, wherein the cradle is operatively coupled with a motorized racking mechanism and comprises a base plate; a motor configured on the base plate; and a gearbox, wherein the gearbox has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out..

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
[0025] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0026] FIG. 1 illustrates an exemplary overview of the cradle with motorized racking mechanism in accordance with embodiments of the present disclosure.
[0027] FIG. 2 illustrates an exemplary motorized racking assemblyin accordance with embodiments of the present disclosure.
[0028] FIG. 3 illustrates an exemplary exploded view of the gearbox with motor in accordance with embodiments of the present disclosure.
[0029] FIG. 4 illustrates an exemplary top view of the cradle with assembled gearbox for motorized racking in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION
[0030] 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. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0031] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0032] 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.
[0033] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0034] Various terms as used herein. To the extent a term used in a claim is not defined, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[0035] Aspects of the present disclosure relate to a motorized racking mechanism for draw-out type air circuit breakers. In an aspect, the proposed motorized racking mechanism has a motor and a gearbox for racking one or more air circuit breakers, wherein the gearbox can use gears such as a worm and a worm wheel, a bevel, a rack and pinion for controlling speed in order to get a desired speed reduction and generate a precise torque. Final rotation of the screw can be done with the help of the rack and pinion arrangement. The horizontally arranged gear can be housed as a kit and mounted on the base plate of a cradle. A micro switch can be used for supply cut off to the motor. Direction of the motor can be reversed through a rotation circuit that controls the direction of the motor.
[0036] In an aspect, the motorized racking mechanism includes a motor and a gearbox assembled on the base plate of a cradle, wherein the gearbox has a specific gear arrangement with suitable gear ratios for controlling the speed and generating a torque sufficient for racking operations. When the power is switched on, the motor can start rotating, transmitting power to the gearbox. Various gears of specific ratios can control the rotational speed at various stages resulting in a desired speed reduction at the end that can generate the required torque to a rack that can be engaged to the two pinions, one on the gearbox shaft and the other fixed on the racking screw, for final rotation of racking screw for the racking operation to take place.
[0037] In an aspect, direction of motor can be reversed through a rotation circuit controlling the direction of the motor for racking out of breaker.
[0038] In an aspect, the proposed motorized racking mechanism eliminates human efforts of racking the breaker manually as it presents a motorized racking mechanism for racking the breaker in all three positions, i.e., isolated, test and service. The motorized racking mechanism generates a torque sufficient to perform racking operation on Air Circuit Breakers in a smooth and hassle-free manner, taking care of excess torque, if any. The breaker can be easily moved from service position to maintenance position.
[0039] The proposed disclosure relates to a cradle of a circuit breaker, wherein the cradle is operatively coupled with a motorized racking mechanism, and comprises a base plate; a motor configured on the base plate; and a gearbox, wherein the gearbox has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out.
[0040] In an aspect, when supply is given to the motor, the motor rotates and transmits power to the gearbox to enable stages of speed reduction and sufficient torque to the provided to rack, wherein the rack connects the gearbox with racking screw. The motor can be fixed on the base plate by a holding bracket.
[0041] In another aspect, the motor can be mounted on side plate, wherein a motor pinion can be mounted on the motor such that when supply is given to the motor, the pinion that is engaged with a helical gear starts rotating. In an aspect, the helical gear can be compounded with worm, wherein by rotation of the worm, worm wheel mounted on a worm wheel shaft starts rotating. A spur gear that is mounted on the worm wheel shaft can get engaged with a second spur gear that is mounted on a spur gear shaft, wherein bevel gear that is also mounted on the spur gear shaft rotates along with the spur gear. In an aspect, the spur gear shaft has bearings mounted on top cover and bottom plate such that with rotation of the bevel gear, bevel pinion that is mounted on racking pinion shaft rotates, and wherein racking pinion is compounded with the bevel pinion, and wherein the racking pinion shaft is supported with a shaft support to enable motion to be transferred from motor rotation to racking pinion rotation with sufficient speed reduction and increased torque.
[0042] In an aspect, rack can be operatively coupled with a racking pinion of the gearbox such that with rotation of the racking pinion, the rack converts rotational motion to translational and rotates racking screw pinion mounted on racking screw such that the racking operation takes place with the rotation of the racking screw. In an aspect, travel of the rack can be guided by two rack guides, wherein the racking screw can be mounted on support bracket.
[0043] In an aspect, direction of the motor can be reversed for performing racking out operation.
[0044] The present disclosure further relates to a circuit breaker that is operatively coupled with a cradle, wherein the cradle is operatively coupled with a motorized racking mechanism and comprises a base plate; a motor configured on the base plate; and a gearbox, wherein the gearbox has a gear arrangement with suitable gear ratio for providing torque for racking operation of the circuit breaker to be carried out.
[0045] In an aspect, with reference to FIGs. 1-4, exemplary views of the proposed cradle 1 with motorized racking mechanism 23 in accordance with various embodiments of the present disclosure have been shown. The figures show cradle 1 of a draw-out air circuit breaker with a motorized racking mechanism 23 assembled on a base plate 2 with a motor 3 and a gearbox 28.The motor 3 can be fixed on the base plate 2 by a holding bracket 4. The rack 18 connects the gearbox 28 with racking screw 20.
[0046] In an aspect, the motorized racking assembly 28 can include the motor 3 and the gearbox 28, wherein FIG. 3 illustrates an exemplary exploded view of the gearbox 28 with motor 3 in accordance with embodiments of the present disclosure. The motor 3 can be mounted on the side plate 24. Motor pinion 6 can be mounted on the motor 3 such that when supply is given to the motor 3 it starts rotating, causing the motor pinion 6 engaged with a helical gear 7 to start rotating. The helical gear 7 can be compounded with the worm 8, causing a rotation in the worm 8. The rotating worm 8 causes the worm wheel 9 mounted on the worm wheel shaft 10 to rotate. Spur gear 29 mounted on the worm wheel shaft 10 gets engaged with the spur gear 13 mounted on the spur gear shaft 11. Bevel gear 14 also mounted on the spur gear shaft 11 rotates along with the spur gear 13. The spur gear shaft 11 has bearings 26 mounted on the top cover 9 and the bottom plate 25. With the rotation of the bevel gear 14, the bevel pinion 15 mounted on the racking pinion shaft 12 starts rotating. The racking pinion 16 is compounded with the bevel pinion 15. The racking pinion shaft 12 is supported with a shaft support 27. Thus, the motion is transferred from the motor 3to the racking pinion16with necessary reduction in the speed to achieve desired increase in the torque.
[0047] FIG. 4 illustrates an exemplary top view of the cradle 1 with assembled gearbox 28 for motorized racking in accordance with embodiments of the present disclosure. As shown in FIG. 4, the rack 18 is engaged with the racking pinion 16. With the rotation of racking pinion 16, the rack 18 converts rotational motion into translational motion and rotates the racking screw pinion 17 mounted on the racking screw 20. With the rotation of the racking screw 20, the racking operation takes place. Travel of the rack 18 can be guided by two rack guides 22. The racking screw 20 can be mounted on the support bracket 21.While racking out, direction of the motor 3 can be reversed through a motor direction rotation circuit (not shown).
[0048] In an aspect, the proposed disclosure presents a cradle with a motorized racking mechanism assembled with a motor and a gearbox on the base plate of the cradle, wherein the gearbox has a specific gear arrangement with suitable gear ratio for providing sufficient torque for racking operation to be carried out. When supply is given, the motor rotates and transmits power to gearbox and then through stages of speed reduction, sufficient torque is provided to a rack engaged to two pinions one on the gearbox shaft and other fixed on the racking screw for final rotation of racking screw for racking operation to take place.
[0049] In an aspect, direction of motor can be reversed through a circuit for motor direction rotation for racking out of breaker.
[0050] In another aspect, the gearbox can include gear arrangement using gears such as worm and worm wheel, bevel, spur helical gears, rack and pinion, for providing larger reduction in speed and increase in torque required to carry out the racking operation. It is to be appreciated that the proposed gearbox arrangement is only one exemplary implementation of the gearbox, and any other mode/construction/structure of making the proposed gearbox is completely with in the scope of the present disclosure till the time the same is being used for use in motorized racking of circuit breakers. In an aspect, the gearbox is horizontal, and the gear arrangement can be enclosed in a housing as a kit, wherein the complete assembly can be mounted on the base plate of the cradle. A micro-switch can be used for supply and cut off to the motor, wherein direction of the motor can be reversed through a circuit for motor direction rotation circuit.
[0051] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

ADVANTAGES OF THE INVENTION
[0052] The present disclosure provides a system and method for motorized racking mechanism for draw-out type air circuit breakers.
[0053] The present disclosure provides a cradle of a circuit breaker that has a motor and gearbox for racking operation of circuit breaker.
[0054] The present disclosure provides a cradle that uses a rack and pinion arrangement for rotating racking screw to perform the racking operation.
[0055] The present disclosure provides a cradle that provides sufficient torque for racking the breaker and reducing manual efforts.