FORM 2
The Patents Act 1970
(39 of 1970) &
The Patent Rules 2003 COMPLETE SPECIFICATION
(See Section 10 and rule 13)


TITLE OF THE INVENTION:
STORED ENERGY MOTOR OPERATING SYSTEM FOR CIRCUIT BREAKER OPERATION
APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai, 400 001, Maharashtra .
INDIA.
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED


A) TECHNICAL FIELD
[0001] The present invention generally relates to the circuit switching devices and circuit interrupters such as circuit breakers, contactors, motor starters, motor controllers and load controllers. The present invention particularly relates to molded case circuit breakers and more particularly to a stored energy motor operating mechanism used for switching the operation of the circuit breakers.
B) BACKGROUND OF THE INVENTION
[0002] The circuit switching devices such as circuit breakers are used to protect electrical circuitry and equipment from damage due to abnormal condition, such as an overload condition or a relatively high level short circuit or fault condition. Once a fault is detected, the contacts within the circuit breaker are opened to interrupt a circuit and the mechanically-stored energy in springs or compressed air is provided within the circuit breakers to separate the contacts. Small circuit breakers are manually operated whereas the larger circuit breakers have solenoids to trip the circuit breaker and electric motors are used to restore the energy into the springs.
[0003] The circuit switching devices are usually installed in an enclosure to have an entire control over the switching devices and to provide the operation of the switching devices externally to prevent a potential hazard to the personnel and access to the high voltage. One of the switching devices is a moulded case circuit breaker which is used

to provide an over current protection for various types of electrical equipments. However, in some applications, it is desirable to have the accessories arranged external to the circuit breaker enclosure for various other applications coupled with parent application i.e. the circuit breaker. The examples of external accessories include, a rotary extended mechanism intended to operate the circuit breaker externally from the circuit breaker enclosure for improving the operator safety. One more example includes, an electrical operator intended to provide the circuit breaker operation remotely.
[0004] The External accessories are mechanically coupled to an operating knob of the switching devices. The external accessories have actuating mechanism which includes a knob holder to hold the operating knob of the switching devices. The desired rotary or reciprocating motion is given to the knob holder through intended mechanisms. Further the knob holder carries the operating knob of the switching devices to one of ON, OFF or RESET states respectively.
[0005] In current scenario, only a portion of stored energy is used to close the circuit breaker. Thus the energy is wasted in overcoming the resistance introduced by the components used in charging systems. Further, when the charging system is manually operated, it can be interrupted or overrun. Yet in another scenario, some of the inventions use two springs of different stiffness for charging and discharging mechanisms provided in motor operating system for the switching operations in the circuit breaker.

[0006] In light of the foregoing discussion, there exists a need to provide a mechanism that minimizes the stored energy required for opening, closing and resetting operations of the circuit breaker mechanism. There exists a need to provide a stored energy motor operating system with less number of components for circuit breaker operation. Also, there exists a need to provide a stored energy motor operating system with unidirectional motion of mechanism to achieve the charging and discharging operations of a charging spring provided in the motor operating system, within one cycle. Also, there is a need for mounting the actuating mechanism in the stored energy motor operating mechanism on the circuit breaker such that the knob holder of the motor operating mechanism engages positively with the operating knob of the circuit breaker.
[0007] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
C) OBJECT OF THE INVENTION
[0008] The primary object of the present invention is to provide a stored energy motor operating system for circuit breaker operation externally or remotely, to drive the circuit breaker to one of ON, OFF or RESET states.
[0009] Another object of the present invention is to provide a stored energy motor operating system for circuit breaker operation with unidirectional motion of

mechanism to achieve the charging and discharging operations of a charging spring provided in the motor operating system, within one cycle.
[0010] Yet another object of the present invention is to provide a stored energy motor operating system for circuit breaker operation with a single spring along with a piston and cylinder arrangement provided in the motor operating system.
[0011] Yet another object of the present invention is to provide a stored energy system in a motor for circuit breaker operation with the actuating mechanism mounted on the switching devices such that the knob holder of the actuating mechanism engages positively with the operating knob of the switching devices.
[0012] Yet another object of the present invention to provide a stored energy
motor operating system for circuit breaker operation with less number of components to provide the higher mechanical advantage in the circuit breaker operation.
[0013] These and other objects and advantages of the present invention will
become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
D) SUMMARY OF THE INVENTION

[0014] The various embodiments of the present invention provides a stored
energy motor operating system for circuit breaker operation externally or remotely, to drive the circuit breaker to one of ON, OFF or RESET states.
[0015] According to one embodiment of the present invention, a stored energy
motor operating system for circuit breaker has a motor arranged on the side plate in the circuit breaker. A gearing system is connected to the motor. A cam shaft is coupled to the motor through the gearing system. A cam plate is attached to the cam shaft. A knob driving mechanism is mounted on a side plate in the circuit breaker. A knob holder is attached to the knob driving mechanism. A roller is provided in the knob holder. A cam pin assembly is mounted on the side plate in the circuit breaker. A charging spring is connected to the knob driving mechanism and to the mechanism side plate. A stopper plate is hinged on to the cam shaft. A latching spring is connected to the stopper plate and to the side plate. A solenoid actuator is mounted on the side plate of the assembly. The stopper plate holds the cam pin assembly after the completion of charging operation to store the entire spring energy on the knob driving mechanism and the solenoid actuator releases the cam pin assembly from the stopper plate to drive the knob driving mechanism to switch on the circuit breaker.
[0016] The motor drives the cam shaft through the gearing system to drive the
cam to displace the cam pin assembly to drive the knob driving mechanism to charge the charging spring. The knob driving mechanism has two side plates. The side plates in the knob driving mechanism has cam pin slot and cam shaft slot to receive the cam pin assembly and the cam shaft respectively. The cam pin assembly has a roller

mounted with cam pin at both ends. The knob holder attached to the knob driving mechanism has two side plates and a roller provided between the two side plates. The charging spring is connected to the knob driving mechanism at one end and to the mechanism side plate at the other end. The stopper plate has a latching profile to latch and hold the cam pin assembly at the end of the charging operation to store the energy in the charging spring.
[0017] The motor drives the cam shaft to drive the cam to displace the cam
pin assembly during a charging operation so that the roller of the cam pin assembly rolls inside the slot of the mechanism side plate and the roller is held between the cam pin and the side plate of the knob drive mechanism. The cam pin assembly is constrained to move in the cam pin slot provided at the side plate in the knob drive mechanism in the cam during the displacement of the cam pin assembly by the cam so that the cam pin assembly drives the knob driving mechanism to charge the charging spring. The solenoid actuator is activated to create a rotational displacement in the stopper plate to release the cam pin assembly from the stopper plate so that the energy stored in the charging spring is used to drive the knob driving mechanism to drive the knob of the circuit breaker.
E) BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The other objects, features and advantages will occur to those skilled
in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[0019] FIG. 1 illustrates a perspective view of a motor operating system for
circuit breaker operation according to one embodiment of the present invention.
[0020] FIG. 2 illustrates a perspective view of a knob driving mechanism in a
motor operating system for circuit breaker operation according to one embodiment of the present invention.
[0021 ] FIG. 3 illustrates a front perspective view of a charging device in a
motor operating system for circuit breaker operation according to one embodiment of the present invention.
[0022] FIG. 4 illustrates an exploded perspective view of a cam pin assembly
of a motor operating system according to one embodiment of the present invention.
[0023] FIG. 5 illustrates a perspective view of a knob holder of knob driving
mechanism in a motor operating system according to one embodiment of the present invention.

[0024] FIG. 6 illustrates a front view of a motor operating system for circuit
breaker operation during the latching operation according to one embodiment of the present invention.
[0025] FIG. 7 illustrates a front view of a motor operating system for circuit
breaker operation during the de-latching operation in a motor operating system for circuit breaker operation according to one embodiment of the present invention.
[0026] Although the specific features of the present invention are shown in
some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[0027] In the following detailed description, a reference is made to the
accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.

[0028] The various embodiments of the present invention provides a stored
energy motor operating system for circuit breaker operation externally or remotely, to drive the circuit breaker to one of ON, OFF or RESET states.
[0029] According to one embodiment of the present invention, According to
one embodiment of the present invention, a stored energy motor operating system for circuit breaker has a motor arranged on the side plate in the circuit breaker. A gearing system is connected to the motor. A cam shaft is coupled to the motor through the gearing system. A cam plate is attached to the cam shaft. A knob driving mechanism is mounted on a side plate in the circuit breaker. A knob holder is attached to the knob driving mechanism. A roller is provided in the knob holder. A cam pin assembly is mounted on the side plate in the circuit breaker. A charging spring is connected to the knob driving mechanism and to the mechanism side plate. A stopper plate is mounted on the knob driving mechanism. A latching spring is connected to the stopper plate and to the side plate in the circuit breaker. A solenoid actuator is mounted on the side plate of the assembly. The stopper plate holds the cam pin assembly after the completion of charging operation to store the entire spring energy on the knob driving mechanism and the solenoid actuator releases the cam pin assembly from the stopper plate to drive the knob driving mechanism to switch on the circuit breaker.
[0030] The motor drives the cam shaft through the gearing system to drive the
cam to displace the cam pin assembly to drive the knob driving mechanism to charge the charging spring. The knob driving mechanism has two side plates. The side plates in the knob driving mechanism has cam pin slot and cam shaft slot to receive the cam

pin assembly and the cam shaft respectively. The cam pin assembly has a roller mounted with cam pin at both ends. The knob holder attached to the knob driving mechanism has two side plates and a roller provided between the two side plates. The charging spring is connected to the knob driving mechanism at one end and to the mechanism side plate at the other end. The stopper plate has a latching profile to latch hold the cam pin assembly at the end of the charging operation to store the energy in the charging spring.
[0031 ] The motor drives the cam shaft to drive the cam to displace the cam
pin assembly during a charging operation so that the roller of the cam pin assembly rolls inside the slot of the mechanism side plate and the roller is held between the cam pin and the side plate of the knob drive mechanism. The cam pin assembly is constrained to move in the cam pin slot provided at the side plate in the knob drive mechanism in the cam during the displacement of the cam pin assembly by the cam so that cam pin assembly drives the knob driving mechanism to charge the charging spring. The solenoid actuator is activated to create a rotational displacement in the stopper plate to release the cam pin assembly from the stopper plate so that the energy stored in the charging spring is used to drive the knob driving mechanism to drive the knob of the circuit breaker.
[0032] FIG. 1 illustrates a side perspective view of a motor operating system
for circuit breaker operation according to one embodiment of the present invention. With respect to FIG. 1, cam 4 is positively attached to a cam shaft 3. The cam 4 is driven by a motor 5 through a gearing system 2 and knob driving mechanism 1 during the charging operation in the motor operating system. A cam pin assembly 12 is

provided in the knob driving mechanism 1. During the charging operation in the motor operating system, the cam pin assembly 12 is driven by the cam 4.
[0033] FIG. 2 illustrates a side perspective view of a knob driving mechanism in a motor operating system, for circuit breaker operation according to one embodiment of the present invention. With respect to FIG. 2, a knob holder 7 is supported between the side plates 6a of the knob driving mechanism. The knob holder 7 is further provided with a roller 8a. The side plates 6a on either sides are provided with a cam pin slot 9 and a cam shaft slot 10 respectively. The cam shaft 3 as shown in FIG. 1 is received by the cam shaft slot 10 and a cam pin assembly 12 as shown in FIG. 1 is received by the cam pin slot 9 of the knob driving mechanism respectively.
[0034] FIG. 3 illustrates a side perspective view of a charging device in a motor operator system for circuit breaker operation according to one embodiment of the present invention. With respect to FIG. 3, a cam 4 is positively attached to a cam shaft 3. The charging operation of the spring 11 in the motor operating system is achieved through displacement of the cam pin assembly 12 into the first slot 9a provided in a mechanism side plate 6b. During charging operation, a roller provided in the cam pin assembly 12 is rolled into the first slot 9a provided in the mechanism side plate 6b and the roller is held between the first slot 9a and a cam pin provided in the cam pin assembly 12, at this position. The cam pin assembly 12 is driven by the cam 4 and the knob driving mechanism is driven by the cam pin assembly 12 respectively. The cam pin assembly 12 is constrained to move into the slot 9a during the charging operation

of the motor operating system. A roller 8a as shown in FIG.2 associated with knob holder 7 is rolled into second slot 9b provided in the mechanism side plate 6b.
[0035] The charging spring 11 provided in the motor operating system gets charged simultaneously during the constrained movement of the cam pin assembly 12 into the first slot 9a. One end of the charging spring 11 is attached to the knob driving mechanism 1 and another end of the charging spring 11 is attached to the mechanism side plate 6b. The charging spring 11 gets fully compressed after the charging operation. Further, a knob associated with the circuit breaker is positively engaged with the knob holder 7 during the charging operation of the circuit breaker. The knob associated with the circuit breaker is moved to OFF position by the charging movement of the cam pin assembly 12 into the first slot 9a and by the charging movement of the knob holder 7 into the second slot 9b.
[0036] FIG. 4 illustrates an exploded perspective view of a cam pin assembly of a motor operating system according to one embodiment of the present invention. With respect to FIG. 4, the cam pin assembly is provided with a cam pin 12a, and a roller 8b on either side of the cam pin assembly. The cam pin assembly is received by a cam pin slot with help of the roller 8b. The roller 8b of the cam pin assembly is rolled into a first slot 9a provided in a mechanism side plate 6b as shown in FIG. 3, during the charging operation of the motor operating system. Further, the roller 8b is held between the cam pin 12a and the first slot 9a provided at mechanism side plate 6b of the motor operating system during the charging operation of the motor operating system.

[0037] FIG. 5 illustrates a perspective view of a knob holder of a knob driving mechanism in a motor operating system according to one embodiment of the present invention. With respect to FIG. 5, the knob holder is provided with the bushes 14. The bushes 14 are supported between supporting plates of knob holder assembly 13. The bush mounted at the extreme end the knob holder is provided with a roller 8a and a knob holder pin 15. During the charging operation in the motor operating system, the roller 8a is rolled into another slot provided in mechanism side plate 6b as shown in FIG. 3 and the bush 14 slides inside the another slot provided in the mechanism side plate 6b as shown in FIG. 3.
[0038] FIG. 6 illustrates a front view of a latching mechanism in a motor operating system for circuit breaker operation during latching operation, according to one embodiment of the present invention. With respect to FIG. 6, a cam 4 is positively attached to a cam shaft 3. The cam 4 is driven by a motor 5 through a gearing system 2 and a knob driving mechanism 1 as shown in FIG. 1, during the charging operation in the motor operating system. Charging operation in the motor operating system is achieved through the displacement of the cam pin assembly 12 into first slot 9a as shown in FIG. 3, provided in a mechanism side plate 6b. During the charging operation, the cam pin assembly 12 is driven by the cam 4.
[0039] The charging spring 11 provided in the motor operating system gets charged simultaneously during the constrained movement of the cam pin assembly 12 into the first slot 9a as shown in FIG. 3. The charging spring 11 gets fully compressed after

the charging operation. After the completion of the charging operation, the cam pin assembly 12 gets latched at the latching area 18 provided on the stopper plate 16. The stopper plate 16 is loaded with a latching spring 17 to hold the cam pin assembly in the charged position after the completion of the charging cycle. In the latched position, the cam pin assembly is held in charged position by the latching spring 17 loaded stopper plate 16. In the latched condition, the entire charged energy of the charging spring 11 gets stored on the knob driving mechanism which is driven by the cam pin assembly during the charging operation.
[0040] FIG. 7 illustrates a front view of a motor operating system for circuit breaker operation during de-latching operation, according to one embodiment of the present invention. With respect to FIG. 7, a cam 4 is positively attached to a cam shaft 3 in the latched condition. Once the circuit breaker gets ON command, the charged energy stored in the charging spring 11 is released during the de-latching operation and the released energy is used to drive the knob driving mechanism. Thus the discharging movement of cam pin assembly 12 provided in the knob driving mechanism 1 is used to move the knob associated with the circuit breaker to ON position thereby causing the circuit breaker to be switched ON. The cam pin assembly 12 is released from the latching spring loaded stopper plate 16 during the de-latching operation. The cam pin assembly 12 is released from the latching spring loaded stopper plate 16 using a solenoid actuator 19.
[0041] The solenoid actuator 19 hits the latching spring loaded mechanism side plates 6b which are hinged onto the cam shaft 3. The actuation of the solenoid

actuator 19 creates a rotational displacement in the latching spring loaded stopper plate 16. Due to the rotational displacement of the latching spring loaded stopper plate 16, the cam pin assembly 12 is released from the stopper plate 16. The released energy from the charging spring 11 is utilized to switch ON the circuit breaker since the knob associated with the circuit breaker is held with knob holder 7 of the knob driving mechanism 1. During the discharging operation, the bush 14 provided in the knob holder 7 of the knob driving mechanism 1 slides inside a second slot 9b provided in the mechanism side plate 6b. The second slot 9b is as shown in FIG. 3.
G) ADVANTAGES OF THE INVENTION
[0042] Thus the various embodiments of the present invention provide a stored energy motor operating system for circuit breaker operation. The invention provides unidirectional motion to achieve the charging and discharging operations of a charging spring provided in the motor operating system, within one cycle. The knob holder of the motor operating system engages positively with the operating knob of the circuit breaker. The motor operating system minimizes the stored energy required for opening, closing and resetting operations of the circuit breaker. The motor operating system is provided with less number of components which is cost effective and has higher mechanical advantage for operating the circuit breaker.
[0043] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims.

[0044] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter of language might be said to fall there between.

To,
The Controller of Patents,
The Patent office,
At Chennai

CLAIMS
What is claimed is:
1. A stored energy motor operating system for circuit breaker including a side plate comprising:
A motor arranged on the side plate in the circuit breaker; A gearing system connected to the motor; A cam shaft coupled to the motor through the gearing system; A knob driving mechanism mounted hingedly on the cam shaft; A knob holder attached to the knob driving mechanism; A roller provided in the knob holder;
A cam pin assembly mounted on the side plate provided in the circuit breaker; A charging spring connected to the knob driving mechanism and to a mechanism side plate;
A stopper plate mounted on the knob driving mechanism; A latching spring connected to the stopper plate and to the side plate in the circuit breaker; and
A solenoid actuator mounted on the side plate in the circuit breaker; Wherein the stopper plate holds the cam pin assembly after the completion of charging operation to store the entire spring energy on the knob driving mechanism and the solenoid actuator releases the cam pin assembly from the stopper plate to drive the knob driving mechanism to switch on the circuit breaker.

2. The system according to claim 1, wherein the motor drives the cam shaft through the gearing system to drive the cam to displace the cam pin assembly to drive the knob driving mechanism to charge the charging spring.
3. The system according to claim 1, wherein the knob driving mechanism has two side plates.
4. The system according to claim 1, wherein the side plates in the knob driving mechanism has cam pin slot and cam shaft slot to receive the cam pin assembly and the cam shaft respectively.
5. The system according to claim 1, wherein the cam pin assembly has a roller mounted with cam pin at both ends.
6. The system according to claim 1, wherein the knob holder attached to the knob driving mechanism has two side plates and a roller provided between the two side plates.
7. The system according to claim 1, wherein the charging spring is connected to
the knob driving mechanism at one end and to the mechanism side plate at the
other end.
8. The system according to claim 1, wherein the stopper plate has a latching
profile to latch hold the cam pin assembly at the end of the charging operation
to store the energy in the charging spring.

9. The system according to claim 1, wherein the motor drives the cam shaft to drive the cam to displace the cam pin assembly during a charging operation so that the roller of the cam pin assembly rolls inside the slot of the mechanism side plate and the roller is held between the cam pin and the side plate of the knob drive mechanism.
10. The system according to claim 1, wherein the cam pin assembly is constrained to move in the cam pin slot provided at the side plate in the the knob drive mechanism in the cam during the displacement of the cam pin assembly by the cam so that cam pin assembly drives the knob driving mechanism to charge the charging spring.
11. The system according to claim 1, wherein the solenoid actuator is activated to create a rotational displacement in the stopper plate to release the cam pin assembly from the stopper plate so that the energy stored in the charging spring is used to drive the knob driving mechanism to drive the knob of the circuit breaker.