F0RM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention. - AN IMPROVED ELECTRICAL INTELLIGENCE
IN STORED ENERGY ELECTRICAL OPERATING MECHANISM FOR MOULDED CASE CIRCUIT BREAKER
2. Applicant(s)
(a) NAME : LARSEN & TOUBRO LIMITED
(b) NATIONALITY : An Indian Company.
(c) ADDRESS: L & T House, Ballard Estate, Mumbai 400 001,
State of Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
The present invention relates to an improved electrical wiring circuit of an electrical operating mechanism of a moulded case circuit breaker, which provides an interlocking arrangement for manual charging and automatic charging. More particularly, the invention relates to an improved electrical intelligence in stored energy electrical operating mechanism for moulded case circuit breaker where the electrical circuit with five terminals is adapted to provide an interlocking arrangement for dual operations of Electrical Operating Mechanism i.e. charging (OFF state) and discharging(ON state) with the help of toggle switch.
BACKGROUND OF THE INVENTION
The prior art electrical circuit of Electrical Operating mechanism (EOM) for moulded case circuit breaker (MCCB) consist of six terminals.
Electrical circuit diagram of Legrand Electrical Operating Mechanism for MCCB in figure 1 shows that the MCCB circuit has a 6 terminal arrangement.
Further figure 2 shows electrical circuit with 6 terminal of Schneider Electrical Operating Mechanism for MCCB.
Moreover the prior art circuit use micro-switch for interlocking means of dual operations. Dual operations comprises of the charging and the discharging operations.
Therefore the prior art methods of sensing the charging and discharging cycle use micro-switch. The micro-switch senses the position of a circular hub which rotates during charging and discharging cycles which are the two operations performed. The sensing methods use a single pole micro-switch in which NO and NC terminals are used for charging and discharging cycles respectively and C is common to both circuits (motor circuit and solenoid circuit). The sensing of the ON and OFF states of MCCB cannot be done with the help of micro-switch.
Further as both the circuits for its two operations use a single pole micro-switch therefore one circuit dose not get isolated when the other circuit is in active state. Therefore making is complicated and cumbersome.
US 5,302,786 discloses a molded case circuit breaker of the type containing an electronic trip unit to control an operating mechanism for automatically turning the circuit breaker

contacts between ON and OFF conditions under overload conditions and a handle operator for same under quiescent conditions is designed for operation with a motor operator unit. The operating mechanism unit is structured to resist the high impact forces translated to the mechanism by the motor operator unit.
US 6,734,768 discloses a remote controller of a circuit breaker capable of making an maintenance man control a circuit breaker instantly and safely at any place without approaching a certain area such as a control board or a control room, the circuit breaker includes a receiver for receiving a radio control signal for turning on/off or tripping a circuit breaker; a control unit for generating a first control signal or a second control signal depending on the radio control signal inputted from the receiver; a motor driver for controlling the on/off operation of the circuit breaker depending on the first control signal; and a trip unit for tripping the circuit breaker depending on the second control signal.
US 6,015,959 discloses a molded case electric power switches such as circuit breakers, disconnects and transfer switches have an energy storage spring which rotates a cam assembly to close and initiate opening of the switch contacts. The cam assembly includes a drive cam with a cam lobe which engages a drive cam follower on the moving contact assembly. Due to space limitations, the cam assembly is positioned so that the drive cam follower initially moves toward the cam assembly during closing. To accommodate for this, the cam lobe has a generally radial leading edge to prevent binding of the drive cam follower. A single latch mechanism latches the cam assembly in a spring charged position and in a closed position. A Y-shaped latch member has one leg which is engaged by a latch, a second leg which engages stops on the drive cam at the charged position and the closed position, and a third leg which sequentially engages the stops to reset the latch mechanism. The cam assembly, a charging mechanism including a rachet wheel and handle, the latch mechanism and the energy storage spring are all mounted between and supported by a pair of side plates. In a multi-pole switch, the drive cam engages the moving contact assembly of one pole, which is coupled to the moving contact assemblies of the other poles by a crossbar.
US 5,300,907 An operating for a circuit breaker including a pivoting handle for controlling opening and closing of the circuit breaker and resetting of the latch after tripping. The handle bears a resetting roller, which cooperates with a cam surface of the latch, which surface has a first cam section and a second cam section separated by a slope change point. The second section corresponds to the reset position and the slope of this section is chosen in such a way as to obtain a stable reset position of the handle.

US 4,736,174 discloses a circuit breaker operating mechanism for automated assembly finds application within circuit breakers of different ampere ratings. The circuit breaker contacts are opened and closed by means of a roller connected to the circuit breaker operating handle through a cradle link and a cam arranged on the movable contact carrier. The operating springs, cradle and latch are first assembled to the operating mechanism prior to assembly of the operating mechanism within the breaker housing.
US 4,650,944 discloses a molded case circuit breaker includes a highly integrated operating mechanism having an over-center, trip-free, pivot transfer toggle mechanism for opening and closing a pair of electrical contacts in response to overload and short circuit or fault current conditions. The toggle mechanism includes a pair of stationary, spaced apart links and a pair of movable, spaced apart toggle links. Each of the movable links includes an integrally formed, first or initial pivot point formed along its surface for engagement with a surface of one of the stationary links. Each of the stationary links includes a second pivot point formed along its surface for engagement by a surface of one of the movable links. The movable links are sequentially pivotably movable during a trip operation of the circuit breaker initially about the first pivot points and subsequently about the second pivot points. The movement of the movable links about the first pivot points effect a rapid separation of the electrical contacts at the beginning of the trip operation. The movement of the movable links about the second pivot points effect a rapid acceleration of a movable electrical contact during a subsequent portion of the trip operation to increase the arc voltage and thus rapidly extinguish any electrical arc between the electrical contacts.
US 4,528,531 discloses a molded case circuit breaker includes a highly integrated operating mechanism having an over-center toggle mechanism for opening and closing a pair of electrical contacts and a trip mechanism for responding to overload and short circuit or fault current conditions to separate the pair of electrical contacts. A generally flat, intermediate latch plate includes an upper latch surface for latching with a movable cradle of the over-center toggle mechanism and a lower latch surface for latching with a trip bar of the trip mechanism and a pair of outwardly projecting pivot arms disposed between the upper and lower latch surfaces. The over-center toggle mechanism includes a pair of upper toggle links and a pair of lower toggle links interconnected by a toggle spring pin. To increase the speed of separation of the first and second electrical contacts during a trip operation, the cradle is physically configured to engage and upwardly propel the toggle spring pin and, also, the upper toggle links have projections for physically contacting a rigid stop.
The disadvantage of the above mentioned prior art methods is that they are focused entirely on physical mechanisms inside an Electrical Operating Mechanism for moulded case circuit

breaker. There is no mechanism disclosed in the prior art, which relates to the electrical intelligence inside an electrical operating mechanism for moulded case circuit breaker.
To incorporate the electrical intelligence the EOM requires a lesser terminal arrangement than that mentioned in the prior art. The arrangement of the prior art is a bulky and costly one. Further the use of a single pole micro switch is an added disadvantage. The motor which is used in the prior art dose not have any protection.
Thus there is a need to provide an improved mechanism, which would incorporate electrical intelligence with help of stored energy inside the electrical operating mechanism for MCCB. Further to provide a circuit, which requires lesser space to fit in the EOM and reduces cost at the same time. Further protection of the motor is necessary.
OBJECTS OF THE INVENTION
The main object of the present invention is to overcome the disadvantages of the prior art. Another object of the present invention is to provide an improved EOM for selection of manual and automatic mode of charging/discharging with the help of micro switch.
Yet another object of the present invention is to provide an improved mechanism for mounting of EOM on MCCB correctly for proper functioning.
Yet another object of the present invention is to provide an improved mechanism for dual operation of EOM (charging and discharging) with the help of toggle switch.
Yet another object of the present invention is to provide an improved mechanism for protection the motor used.
Yet another object of the present invention is to provide an improved mechanism for activating charging cycle (switching off cycle) with a pulse of 25msec.
Yet another object of the present invention is to provide an improved mechanism, which use push buttons for remotely operating the EOM for ON,OFF and RESET sates and a lamp for checking the healthiness of internal circuit.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided an improved stored energy electrical operating mechanism (EOM) mounted into an electrical circuit assembly of a moulded case circuit breaker (MCCB) for switching ON (charging operations), switching

OFF (discharging operations) and RESET operations remotely either in manual mode or automatic mode, said mechanism comprising:
(i) five terminals arrangement of said electrical circuit;
(ii) plurality of pole switch means comprising two sets of plurality of contacts
operatively in association/connection with said 2nd and 4m terminals of
said circuit adapted to control said charging and discharging operation ;
(iii) a charging device means which is operatively connected with one of the
said pole switch means of said circuit adapted to execute/perform said
charging operation to switch OFF the said circuit;
(iv) a discharging device means which is operatively connected with one of
the said pole switch means of said circuit adapted to execute/perform discharging operations to switch ON the said circuit;
(v) a fuse means operatively connected with the 1st terminal of said circuit
adapted to protect said charging device from undesirable conditions;
(vi) an auto/manual micro switch means placed operatively in alignment with
the said fuse on the 1st terminal of said circuit adapted to execute selection of either said manual mode or said automatic mode for said
charging and discharging operations ;
(vii) a base micro switch means placed substantially in-between said fuse and
said auto/manual switch adapted to execute sensing/detection of the proper mounting of said EOM on said MCCB;
(viii) plurality of button means placed substantially in-between the said third
terminal of said circuit adapted to send signals to said circuit for initiating
the said charging and discharging operations.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Figure 1 illustrates electrical circuit diagram of Legrand Electrical Operating Mechanism for MCCB
Figure 2 illustrates electrical circuit diagram of Schneider Electrical Operating Mechanism for MCCB.
Figure 3 illustrates the method of manual charging by means of operating handle of the present invention.
Figure 4 illustrates the electrical circuit diagram of a stored energy type EOM for MCCB.

DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to internal and external electrical circuit of a Stored Energy Electrical Operating Mechanism (EOM) of a moulded case circuit breaker (MCCB).
There are three states of a MCCB that is the ON state, OFF state, TRIP state. The EOM has to switch on, switch off and reset it remotely.
The EOM consists of a motor for charging operation, a solenoid for discharging operation and a mechanism with gears.
The charging operation is adapted to switch OFF the MCCB and the discharging operation is adapted to switch ON the MCCB.
The operation from ON state to OFF state is performed by applying a puise to the motor of EOM. While performing this operation, a spring is also charged. At the end of this stroke, supply to the motor is cut-off by toggle switch and the mechanism is latched. When a suitable pulse is applied to a plunger type solenoid, the mechanism de-latches. The energy stored in the spring is sufficient to switch ON the MCCB. The toggle switch now cuts-off supply to the solenoid and at the same time motor circuit gets activated tor next operation. By this means, the states of the MCCB can be operated upon remotely by pulse of a push button.
Figure 4 of the invention illustrates the electrical circuit diagram of a stored energy type EOM for MCCB. The circuit with hatched line is an external circuit and below it is an internal circuit. Following are the components in the circuit.
Cartridge fuse (1) Base micro-switch (2) Auto / manual micro-switch (3) Delay micro-switch (4) Toggle switch (5) Universal motor (6) Solenoid (7) Mini fit connector (8) Spring type connector (9) Push to OFF button (10) Push to ON button (11) Lamp (12)

The EOM consists of electrical intelligence in the following mechanism as sated below.
The present invention relates to the interlocking arrangement for dual operations of EOM viz. charging and discharging by the use of toggle switch.
The present invention further relates to the simplified 5 terminal arrangement which can be wired externally. The present invention relates the use of a two pole toggle switch, C and NO terminals of one pole and C and NC terminals of other pole are used for charging and discharging cycles respectively. This completely isolates one circuit when the other circuit is in active state. Charging operation corresponds to OFF state and discharging operation corresponds to ON state. The toggle switch controls the said mechanism.
In the present invention, the toggle switch is placed at the center of MCCB ON and OFF positions; thereby actually sensing the two states of MCCB i.e. ON & OFF states and is the control mechanism
The two pole toggle switch has three terminal namely the NO (normally open), NC (normally close) and C (common) terminals.
Mini fit connectors (8) are of male - female type. The wires are crimped inside an insulating housing of connector by crimp terminals.
Charging operation is performed by the motor(6) when Push to OFF push button(10) is pressed. The function of delay micro-switch(4) is such that, when Push to OFF push button is pressed, it gets turned on after 25 msec. After this period, even if the Push to OFF push button is released, the charging cycle continues until MCCB is switched OFF by toggle switch(5). During this cycle, spring is also charged. Hence only a push of 25 msec of push to OFF button is required to switch OFF the MCCB. The entire switching OFF operation takes about 250 msec.
Now the solenoid circuit is activated. When Push to ON push button(11) is pressed, the solenoid (7) plunger releases the latching mechanism and the stored energy in the spring (9) switches ON the MCCB. The supply to the solenoid is cut-off by toggle switch again. And now the charging circuit is ready for next operation. The entire switching ON operation takes about 60 msec.
The invention further relates to the motor protection by the use of a cartridge fuse. The protection to the motor is provided by the use of a slow blow cartridge fuse, which is connected in series with the motor circuit. The characteristic of the slow blow fuse are

chosen so as to disconnect the motor circuit in the case of a specified over-current at a specified time; thereby protecting the motor burning.
The motor may draw heavy currents in case of locked rotor conditions, mechanical jamming inside the mechanism, any other abnormal conditions. Under such circumstances, the fuse mefts before the heavy current destroys the motor.
The present invention also relates to an interlocking arrangement for manual charging and automatic charging. Electrical circuit gets isolated if manual mode of operation is selected. The selection of manual mode or automatic mode is done by the use of a micro-switch which is accessible to the user on the front facia of EOM assembly. In automatic mode NC contacts of micro-switch are connected so that the electrical circuit is active. Whereas in manual mode, NO contacts are in the circuit which isolates the electrical circuit. In this mode, charging and discharging operations are performed manually i.e. by operating handle of EOM as shown in figure 3.
The present invention further relates to the interlocking arrangement for mounting of EOM on MCCB. Electrical circuit gets isolated if EOM is not mounted on MCCB correctly. The base micro-switch is mounted below the base of EOM such that its lever gets actuated when EOM is placed on MCCB. Since NO contact of the switch is connected in the electrical circuit, it will close the circuit if and only if its lever gets actuated by mounting the EOM base on MCCB.
The present invention also relates to the use of push buttons and lamp (for indication) externally.
Referring to electrical circuit diagram, one of the terminals of lamp is connected at terminal 3 and the other terminal is connected to Neutral.
The electrical circuit is activated if and only if fuse, base micro-switch (2) and auto/manual switch (3) are activated.
Healthiness of this circuit is indicated by lamp connected at terminal number 3.
The lamp glows if and only if all of the following conditions are met:-
Fuse is healthy. EOM is mounted on MCCB cover correctly so that base micro-switch is
activated. Auto mode is selected by the user.

We Claim
1. An improved stored energy electrical operating mechanism (EOM) mounted into an electrical circuit assembly of a moulded case circuit breaker (MCCB) for switching ON (charging operations), switching OFF (discharging operations) and RESET operations remotely either in manual mode or automatic mode, said mechanism comprising:
(i) five terminals arrangement of said electrical circuit;
(ii) plurality of pole switch means comprising two sets of plurality of contacts operatively in association/connection with said 2nd and 4th terminals of said circuit adapted to control said switch ON .Switch OFF and RESET operations;
(iii) a charging device means which is operatively connected with one of the said pole switch means of said circuit adapted to execute/perform said charging operation to switch OFF the said circuit;
(iv) a discharging device means which is operatively connected with one of the said pole switch means of said circuit adapted to execute/perform discharging operations to switch ON the said circuit;
(v) a fuse means operatively connected with the 1st terminal of said circuit adapted to protect said charging device from undesirable conditions;
(vi) an auto/manual micro switch means placed operatively in alignment with the said fuse on the 1st terminal of said circuit adapted to execute selection of either said manual mode or said automatic mode for said charging and discharging operations ;
(vii) a base micro switch means placed substantially in-between said fuse and said auto/manual switch adapted to execute sensing/detection of the proper mounting of said EOM on said MCCB;
(viii) plurality of button means placed substantially in-between the said

third terminal of said circuit adapted to send signals to said circuit for initiating the said charging and discharging operations.
2. Mechanism as claimed in claim 1 wherein said plurality of pole switch means are toggle switches having two poles viz first pole and second pole.
3. Mechanism as claimed in claim 1 wherein said two sets of plurality of contacts comprising NC {normally close), NO(normalIy open) and C (common) terminals in each set.
4. Mechanism as claimed in claims 1 to 3 wherein said switch OFF operation occurs when said C and said NC terminal of first pole of toggle switch are in contact.
5. Mechanism as claimed in claim 1 to 3 wherein said switch ON operation occurs when said C and said NC terminals of second pole of toggle switch are in contact.
6. Mechanism as claimed in claim 1 wherein said charging device means comprises a universal motor.
7. Mechanism as claimed in claim 1 wherein said charging device means further comprises a solenoid.
8. Mechanism as claimed in claim 1 wherein said plurality of button means comprises push to OFF button and push to ON button.
9. Mechanism as claimed in claims 1 and 6 wherein said motor is adapted to actuate said toggle switch so as to remotely switch OFF said MCCB by applying a pulse with assistance of said push to OFF button and correspondingly charging a spring.
10. Mechanism as claimed in claims 1 and 7 wherein said solenoid is adapted to actuate said toggle switch so as to remotely switch ON said MCCB by applying a pulse with assistance of push to ON button.
11. Mechanism as claimed in claim 1 wherein said push to OFF button being pressed for about 25 msec to switch OFF the MCCB , which is adapted with the help of delay micro-switch.

12. Mechanism as claimed in claim 1 wherein said switching OFF operation takes about 250 msec.
13. Mechanism as claimed in claim 1 wherein said switching ON operation takes about 60 msec.
14. Mechanism as claimed in claim 1 wherein said spring is adapted to switch ON the MCCB with the stored energy inside it during the discharging operation.
15. Mechanism as claimed in claim 1 wherein said automatic mode operation is performed by connection of NC contacts of said auto/manual switch with the said circuit.
16. Mechanism as claimed in claim 1 wherein said manual mode operation is performed by connection of NO contacts of said auto/manual switch with said circuit.
17. Mechanism as claimed in claim 1 wherein said fuse means comprises of a cartridge fuse.
18. Mechanism as claimed in claim 1 further comprises an operating handle for manual mode of operation.
19. Mechanism as claimed in any preceding claim is based on electrical intelligence.
20. Electrical operating mechanism as substantially described hereinbefore with reference to accompanying drawings.