FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention. - IMPROVED PLUG IN MODULE FOR A 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:

TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to a circuit breaker and more particularly, the invention is concerned about an improved plug in module/mechanism for a moulded case circuit breaker for electrically connecting to a control panel.
BACKGROUND AND THE PRIOR ART
The plug-in device is used in panel boards to mount the circuit breaker. The main purpose of the plug-in base is to reduce the downtime in replacing the breaker.
All the busbars or the cables to the breaker are connected in the plug-in base and the rear connector in the circuit breaker makes a direct contact to the plug-in base contacts.
For the other manufactures plug-in, the user has to hold the breaker and pulled back manually for plugging-out operation thus providing difficultly in operation.
In the prior art for draw out operation the user have to hold the breaker and to apply the out ward force directly in the breaker.
The plug-in base is connected to the panel board, where the terminal (l)s of the plug-in base are bolted to the bus bars of the panel board. The major constraint for this type of contact is that these contacts have to engage and disengage frequently. And in engaged condition it have to carry continuous rated current.
Thus there is need to provide a draw out operation that is made simpler by the introduction of rail (13) arrangement arranged inside the plug-in base which is

actuated by a lever (10). By pulling this lever (10) the breaker can be easily withdrawn from the plug-in base.
The present inventors have found an additional mechanism which is incorporated in plug-in, so that just before the circuit breaker contact makes contact with the plug-in contact, it will trip the breaker. After the full insertion, the mechanism removes the trip command and breaker is free to work. Likewise while plug-out before the circuit breaker contact leaves the plug-in contact, it trips the breaker. Because of the introduction of this mechanism, the hazard involving the accidental plug-out or plug-in in the on condition of the circuit breaker is eliminated.
OBJECTS OF THE INVENTION
A basic object of the present invention is to overcome the disadvantages/drawbacks of the known art.
Other object of the present invention is to provide an improved plug-in module/mechanism for moulded case circuit breaker (MCCB) for electrically connecting it to panel boards.
Other object of the present invention is to provide a handle (9) and lever (10) arrangement in a MCCB so that plug-out operation is made simpler.
Yet another object of the present invention is to provide a trip unit mechanism in a MCCB which ensures tripping of the breaker while plug-in and plug-out operation.
These and other advantages of the present invention will become readily apparent from the following detailed description read in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION
There is provided an improved plug in module/mechanism for a moulded case circuit breaker for electrically connecting to a control panel.
According to one embodiment of the present invention, there is provided improved plug in module/mechanism for a moulded case circuit breaker for electrically connecting to a control panel, said module comprising a plug in base (3) to reduce downtime in replacing a breaker; a rail (13) arrangement placed inside said plug in base (3) actuated by a lever (10), said lever (10) on being pulled withdrawing said breaker from said plug in base (3); a handle (9) and lever (10) arrangement placed at side of said plug in base (3) to facilitate plug out operation; a plurality of springs to generate contact pressure; a back plate (5)having duality of bends, said bends connected to rear side of said breaker; a plurality of pins connected to said plate using bolts, two of said pins having extra cylindrical head length connected to a hollow cylindrical shaft for plug out operation.
Other embodiment of the present invention provides a safety trip mechanism (7) tripping said breaker during plug in and plug out operation mounted on rear side of said breaker.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
In the appended drawing:
Fig. 1 illustrates the view of the circuit breaker plugged in Plug-in base.
Fig. 2 illustrates the view of the circuit breaker plugged out from Plug-in base

Fig. 3 illustrates the rear side of the circuit breaker connected with the moving contacts, back plate (5)and trip mechanism unit.
Fig. 4 illustrates the plug-in base.
Fig. 5 illustrates the handle (9) and lever (10) arrangement.
Fig.6 illustrates the rail (13) and lever (10) arrangement in the plug-out position.
Fig.7 illustrates the handle (9), lever (10) and long head pin position at the plug-in position.
Fig.8 illustrates the movement of the handle (9), long head pin and the breaker during plug-out (position retaining spring not shown).
Fig.9 illustrates the trip mechanism unit.
Fig. 10 illustrates the trip mechanism unit connected to the rear side of the breaker.
Fig.l 1 illustrates trip plate actuating rectangular pin.
Fig,12 illustrates the trip actuator just touches the trigger pin while plugging in.
Fig. 13 illustrates the position of trip actuator after touching the trigger pin on further plugging in causing the trip plate actuating pin to move inside.
Fig. 14 illustrates the position of trip actuator after the complete plugging in operation.

Fig. 15 illustrates the position of trip actuator during plugging out operation.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The following drawings are illustrative of particular examples for enabling methods of the present invention, are descriptive of some of the methods, and are not intended to limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description.
Reference is first invited to Fig 1 where an improved plug in module/mechanism for a moulded case circuit breaker for electrically connecting to a control panel is shown.
Fig. 2 shows the circuit breaker plugged out from Plug-in base.
Fig. 3 shows moving contact, circuit, back plate, shaft and trip mechanism unit. Back plate (5)which has two 90 degree bends, connected at the rear side of the breaker is shown.
Fig. 4 shows terminal (1), handle (9), lever (10), shaft, bush, rail (13), trigger pin etc. Two rail (13)s are connected inside the plug-in base, each plate is connected to the base by screws and the distance between the plate and base is maintained by bushes along with the screws.
Fig. 5 shows position retaining spring, handle (9), lever (10) shaft and bush. At the projected end of shaft, a handle (9) is riveted. At the other end of this shaft, which is inside the plug-in, a special designed lever (10) is connected, which will rotate along with the shaft as shown.

Fig. 6 shows handle (9), lever (10), triggering pin (14) and long head pin.
Fig. 7 shows circuit breaker in plugged in position.
Fig. 8 shows the anti clock movement of handle (9). The lever (10) which is in contact with the lengthier pin pushes it through the slot, outwards. This pin which is connected to the back plate, which is connected to the breaker, pushes the breaker outwards through the slot disconnecting moving and fixed contacts
Fig. 9 shows the trip plate actuator located inside the plastic casing and on mounted on a pin. It has one slot on one end, which is always in contact with the pin in the trip plate actuating rectangular pin as shown.
Fig. 10 shows the trip plate actuating pin is a long pin having a rectangular cross section, which is extended from the rear side of the breaker to the trip plate inside the circuit breaker
Fig. 11 shows split end of the actuator. It also shows stepped pin type in the actuator.
Fig. 12-15 shows different position of trip actuator during plugging operation.
The invented system is thus an improved plug in module for a moulded case circuit breaker for electrically connecting to a control panel.
DETAILED DESCRIPTION OF THE INVENTION
Accordingly in the present invention an improved plug-in module/mechanism for moulded case circuit breaker (MCCB) for electrically connecting it to panel boards is provided.

The present invention consists of a contact connected with the Circuit Breaker (also called as moving contact as the breaker can be moved), fixed contact which is connected with the plug-in base, and springs for contact pressure.
The purpose of the present system is to electrically connect the circuit breaker with the plug-in base.
In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and illustrate the best mode presently contemplated for carrying out the invention. Further functioning of the mechanism has been discussed below to describe the way the mechanism operates. However, such description should not be considered as any limitation of scope of the present unit. The structure thus conceived is susceptible of numerous modifications and variations, all the details may furthermore be replaced with elements having technical equivalence. In practice the materials and dimensions may be any according to the requirements, which will still be comprised within its true spirit.
The handle (9) provided at the side of the plug-in base. A rail (13) is also provided in the plug-in for the free in and out movement (figure 4). A mild steel (MS) back plate, which has two 90 degree bends, is connected at the rear side of the breaker as shown (figure 3). Seven number of special pins, Which has a cylindrical head on one end and threads at other end, are connected to the plate using bolts as shown (figure 3). Out of the seven pins two pins have extra cylindrical head length, for plug-out purpose, is connected to a hollow cylindrical MS shaft (figure 3). This shaft saves the purpose of holding both pins and prevents the bend back of the plates over time or temperature variations. So that the distance between the between plates remains constant all the time.

Two MS rail (13)s are connected inside the plug-in base, each plate is connected to the base by 3 screws and the distance between the plate and base is maintained by 3 bushes along with the screws (figure 4).
Two special designed MS shaft is connected in between this rail (13)s and the plug-in base. This shaft is free to rotate and one end is projected outside the plug-in as shown (figure 4). At the projected end of this shaft, a handle (9) is riveted. At the other end of this shaft, which is inside the plug-in, a special designed lever (10) is connected, which will rotate along with the shaft (figure 5). This shaft pushes the breaker out, in the plug-out operation, when the operating handle (9) is pulled down. This lever (10) is held in this position by the help of another bush, here after called as bush 2 (figure 4 & 5), which is located in between this lever (10) and the rail (13).
After the pull-out operation, the handle (9) and the lever (10) is pulled to the home position by the position retaining spring, connected to the lever (10) (figure 5). While plug-in operation this seven special pins got engaged in the slot given in the rail (13)s. When the handle (9)s are pulled down for a plug-out operation, the shaft connected at the end of the handle (9) rotates. The lever (10), which is connected to the shaft rotates.
The lever (10) which is in contact with the lengthier pin pushes it through the slot, outwards. This pin which is connected to the back plate (5)is connected to the breaker, pushes the breaker outwards through the slot disconnecting moving and fixed contacts (figure 8), thus achieving a successful plug-out operation.
In plug-in base the Plug-in contacts are always at live condition, in which the circuit breaker is to be connected. So it is essential that the circuit breaker have to be in tripped condition or in off condition, both in plug-in operation and in Plug-out

operation, after this operation the breaker should work independently. This can be achieved by the introduction of a safety trip mechanism (7) in the breaker, which will trips the breaker while plug-in operation and plug-out operation. The safety trip mechanism (7) consists of a plastic case having a rectangular slit at the centre, a position retaining double torsion spring, a trip plate actuating rectangular pin, a special shaped trip plate actuator, a stopper pin (20)(20)located in the plastic case and a trigger pin located in plug-in base.
The trip plate actuating pin is a long pin having a rectangular cross section, which is extended from the rear side of the breaker to the trip plate inside the circuit breaker (figure 10). It is arranged in such a manner that a slight inside movement of this pin will actuate the trip plate, which in turn trips the breaker. It has a split head which holds a pin, and a stepped pin type projection (figure 11) which will act as a guide and moves inside the slot given in the plastic case. The plastic case is to be connected at the rear side of the breaker (figure 10). The trip plate actuating pin is placed in the rectangular slit in the plastic casing and the rectangular slit at the rear side of the breaker.
The trip plate actuator is located inside the plastic casing and on mounted on a pin. It has one slot on one end, which is always in contact with the pin in the trip plate actuating rectangular pin as shown (figure 9) and the other end protruded outside the plastic casing. This trip plate actuator is always pushed in anticlockwise direction by the double torsion spring which is also located in the same pin, where this trip plate actuator seated. This motion is restricted not beyond an angle by the stopper pin, which is also located in the plastic case (figure 9). The whole arrangement is located in the special provision given rear side of the circuit breaker, and moves along with the circuit breaker in the plug-in and plug-out operation. The trigger pin is located in the plug-in base connected to the rail (13) as shown in figure (figure 4).

While plug-in, the protruded end of the trip plate actuator makes first contact with the triggering pin (14). On the further inside movement causes the trip plate actuator to rotate downwards, against the double torsion spring action. This in turn results in pushing of trip plate actuating pin, which in turns actuate the trip plate of the circuit breaker causing the tripping of the breaker before the plug-in contacts makes contact with the circuit breaker rear contacts (figure 12 &13). At the full insertion time the trip plate actuator profile again comes in the home position because of the special shape of the trip plate actuator accompanied by the action of the double torsion spring (figure 14). Now the trip plate of the circuit breaker is free and the breaker is free to operate, thus achieving a successful tripping operation at the plug-in operation.
While Plugging out, the trip plate actuator profile again get contact with the triggering pin (14), causing it to rotate downwards, against the double torsion spring action, this in turn results in pushing of trip plate actuating pin, which in turns actuate the trip plate of the circuit breaker causing the tripping of the breaker before the plug-in contacts leaves the rear contacts of the circuit breaker (figure 15), thus achieving a successful tripping operation at the time of draw-out operation.
Benefits:
• Easy disengagement with the help of handle (9) and rail (13) arrangement.
• Better safety in plug-out and plug-in operations with the help of safety trip.
Features:
• The handle (9) and rail (13) arrangement for the easy plug out, so that the breaker can be ejected from the plug-in base easily.

• The introduction of the safety trip mechanism (7) , which can be mounted on the rear side of the breaker and which trips the breaker both in the plug-in and plug-out operation with minimum number of components.
• By the introduction of handle (9) and lever (10) arrangement plug-out operation made simpler. Introduction of trip unit mechanism which ensures tripping of the breaker while plug-in and plug-out operation.
• A handle (9) and rail (13) arrangement is provided for easy disengagement of the breaker at plug-out operation.
• A safety trip mechanism (7) which ensures tripping of the breaker both at plug-in and plug-out operation.
• At any point of time, the breaker can be easily replaced by the new one.
• A safety trip device is employed so that even if it tried to plug-out or plug-in with the breaker in on condition before making the breaker contacts with the plug-in base contact, it will trip the breaker.
Although the embodiments herein are described with various specific embodiments, it will be obvious for a person skilled in the art to practice the embodiments herein with modifications. However, all such modifications are deemed to be within the scope of the claims.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the embodiments described herein and all the statements of the scope of the embodiments which as a matter of language might be said to fall there between.

WE CLAIM
1. An improved plug in module/mechanism for a moulded case circuit breaker for electrically connecting to a control panel, said mechanism comprising:
a plug in base (3) to reduce downtime in replacing a breaker;
a rail (13) arrangement placed inside said plug in base (3) actuated by a lever (10) means, said lever (10) means on being pulled withdraw said breaker from said plug in base (3);
a handle (9) and lever (10) arrangement placed at one side of said plug in base (3) to facilitate plug out operation;
a safety trip mechanism (7) tripping said breaker during plug in and plug out operation mounted on rear side of said breaker;
a plurality of spring means to generate contact pressure;
a back plate (5) having duality of bends, said bends connected to rear side of said breaker;
a plurality of pin means connected to said plate using bolts, two of said pin means having extra cylindrical head length connected to a hollow cylindrical shaft for plug out operation.
2. Mechanism as claimed in claim 1 wherein said connection between plug in base (3) and panel board configured to engage and disengage frequently.
3. Mechanism as claimed in claim 1 carrying continuous rated current during engaged condition.

4. Mechanism as claimed in claim 1 wherein said trip mechanism trip said breaker before said breaker contact making contact with said plug in contact during plug in operation.
5. Mechanism as claimed in claim 1 wherein said trip mechanism trip said breaker before said breaker contact leaves said plug in contact during plug out operation.
6. Mechanism as claimed in claim 1 wherein said rail (13) provide free in and out movement.
7. Mechanism as claimed in claim 1 further comprising a plurality of bushes along with the screws to maintain distance between said plug in base (3) and said plate.
8. Mechanism as claimed in claim 1 further comprising a position retaining spring connected to said lever (10) to pull said handle (9) and lever (10) to initial position after pull out operation.
9. Mechanism as claimed in claim 1 further comprising a trip plate actuator located inside a plastic casing and mounted on a pin.
10. Mechanism as claimed in claim 9 further comprising a stopper pin (20) to control movement of said trip plate actuator.