FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION:
"A Side Indication mechanism for Modular Electric Auxiliary Devices"
2. APPLICANT:
(a) NAME: Larsen & Toubro Limited
(b) NATIONALITY: Indian Company registered under the
provisions of the Companies Act-1956.
(c) ADDRESS: Larsen & Toubro Limited
Electrical & Automation North Wing, Gate 7, Level 0, Powai Campus, Saki Vihar Road, Mumbai 400 072, INDIA
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

A Side Indication mechanism for Modular Electric Auxiliary Devices Field of Invention
The present invention relates to switchgear and modular electrical protection devices especially accessory products such as but not limited to auxiliary contacts, on-off indications, trip indications, trip alarm, under-voltage release, over-voltage release etc.
Background of the Invention
In the known art it is generally known to couple to an MCB one or more auxiliary modular devices, such as:
- auxiliary contact (ON/OFF indication, trip indication, with or without selector),
- shunt release,
- under voltage release
- overvoltage release etc
Those auxiliary modular devices are mechanically coupled together and with the MCB and are provided by actuating means for actuating the operation of the electrical devices (for example opening or closing of a circuit or similar operation).
The auxiliary modular devices have two major opposite faces to be mounted, in operation, on the lateral sides of the device.
Actuating means are usually in two parts, a male part and a female part, each one of which is associated to one of such faces the auxiliary modular device. In this way any modular device is provided with a male or female part of the actuating means which is usually fixed with respective face )lelf or right).

Multiple auxiliary devices are then joined in a chain by mutually engaging the male and female parts of the actuating means of one device with those of the two neighboring devices, so as to generate a chain.
Since the male and female parts of the actuating means are usually fixed in position, therefore it is possible only to have either left-chain or right-chain, starting from a MCB. This implies disadvantages since modules born for a left-chain cannot be mounted in a right-chain, thus leading to have two kinds of modules, each one of which provided by male and female parts of the actuating means on the right or left side.
To overcome this problem, there is a solution provided, in which there are two actuating means in which:
The first actuating means have a male part which is mounted on a slider: the male part can be slidably displaced so to protrude from one face or the opposite. The slider has a "Z" shape so that the seat opened next to one face is not in line with the pin protruding from the opposite side.
The second actuating means includes a removable shaft having as well substantially "Z" shape and a corresponding seat: the shaft can be removed from one side, leaving the seat open, and joined to opposite side.
In this way the auxiliary module can be mounted either on a left-chain or on a right-chain.
The above mentioned prior art solution has following drawbacks:
The first actuating means has the slider positioned not on the axis of rotation, but eccentrically, the slider is joined to the handle, which is usually made in plastic,

this generates an high momentum during actuation (by rotation of the handle) and can cause breakage of the actuating means.
The second actuating means comprised a metallic shaft curved twice about an angle of 90° (substantially in a "Z" shape). When the user disengage the shaft from one side of the auxiliary device and wants to engage the same to the other side, then he must rotate and carefully rotate the shaft, which is quite difficult to perform also because of very small dimensions of the shaft and seat.
Another drawback lies in the fact that, once a multiplicity of auxiliary modular devices and MCBs are mounted together in a same complex of electrical board. An operator may get confused in understanding which auxiliary modular devices are connected to which MCB (i.e. understanding if it is a left-chain or a right-chain).
This drawback is made even worse considering that auxiliary modular devices and/or MCBs in the same electrical board must be mounted in a strict contact each other so as to guarantee an high safety level and a reduction in occupied spaces.
The solution in which the actuating means are provided on the electrical device are movable at least between a first position in which they are operational on one side of the electrical device and a second position in which they are operational on the opposite side of the electrical device. The first actuating means is provided with a slider which slide on its axis of rotation, particularly the axis of rotation of the handle of the MCB and Auxiliary device. This solved the problem of high torque transmission and breakage. The second actuating means comprises a detachable double shaft having two opposite ends provided with different shape and developing each other on the same axis as shown in figure 1.

Objects of the Invention
Object of the present invention is to provide a side indication mechanism for modular electric auxiliary devices, which is reduces confusion in understanding which auxiliary modular devices are connected to which MCB (i.e. understanding if it is a left-chain or a right-chain).
Another object of the present invention is to provide a side indication mechanism for modular electric auxiliary devices, which makes the indication fool-proof thereby eliminating chances of wrong indication.
Summary of the invention
According to the present invention there is provided an indicating mechanism for indicating side of coupling of modular electric devices adapted to couple from both side, the mechanism comprising:
an indication window configured on a casing of the modular electric device;
a flag having at least one indicating surface and a protrusion, wherein the protrusion adapted to dispose in a first cavity of a knob, wherein the indicating surface of the flag are visible from the indication window;
a pin disposed in a second cavity of the knob, the slit is disposed on the protrusion thereby enabling sliding of the pin therearound for connecting another modular electric device,
wherein the slit is partially occupied by the protrusion and the remaining portion shows either of the colour strips thereby indicating the side of coupling.
Brief description of the figures
Figure 1 shows front view of modular auxiliary devices showing actuation element of the prior art;

Figure 2 MCB/RCCB/RCBO or any such device of prior art shown with its both sides;
Figure 3 cross section AA and details of it with a modular electric device;
Figure 4 Flag, knob and pin group of the modular electric device; and
Figure 5 exploded view of the modular electric device;
Figure 6 assembled view of the modular electric device; and
Figures 7a and 7b indication for left-side/right side coupling.
Detail description of the invention
Various embodiment of the present invention provide an actuation mechanism for coupling a plurality of electrical devices, the mechanism comprising a shaft for each electrical device, the shaft having a variable cross-section, the shaft adapted to reversibly engage with an internal operating system of the electrical devices; and a seat on a casing of each electrical device, the seat providing an access to the internal operating system of the electrical devices.
The present invention provides a side indication mechanism for modular electric auxiliary devices. The side indication mechanism reduces confusion in understanding which auxiliary modular devices are connected to which MCB (i.e. understanding if it is a left-chain or a right-chain). Further, the side indication mechanism makes the indication fool-proof thereby eliminating chances of wrong indication.

This present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description.
Refereeing now to figure 3 shows a cross section of a modular electric device (herein after referred as the "device 1") is shown. The device 1 includes a casing 2, a knob 5, and a pin 4. The improvement comprising a flag 6 and an indication window 2c configured on a side portion of the device 1. The flag 6 has a protrusion 6a and indicating surface 6b painted or stuck or another component/components mounted on it for side indication purpose. The knob 5 has a first cavity 5c and a second cavity 5d. The protrusion 6a is disposed in the first cavity 5 c of the knob.
Referring now to figure 4, exploded view of knob 5, the pin 4 and the flag 6 is shown. The pin 4 has a slit 4a. The pin 4 is disposed in the second cavity 5d of the knob 5 and over the flag 6. The slit 4a of the pin 4 is disposed over the protrusion 6a of the flag 6. The slit 4a is disposed on the protrusion 6a thereby enabling sliding of the pin 4 therearound for connecting another modular electric device 1. The pin 4 can be pressed to shift the coupling from other side and a double shaft 11 can be shifted from one side to another side of the device 1 for coupling on desired side refer figure 1. The slit 4a is partially occupied by the protrusion 6s and the remaining portion shows either of the colour strips 6b thereby indicating the side of coupling refer figures 7a & 7b. The colour strips 6b are visible from the indication window 2cs which will guide an operator to indicate on which side the device is connected thereby makes the indication fool-proof thereby eliminating chances of wrong indication
It should be understood that the present invention is not to be limited by the exact details of the illustrated embodiment. However, it is to be taken as the preferred example of the invention and that various changes may be resorted to by a person

skilled in the art without departing from the spirit of the invention or the scope of below mentioned claims. Also, the terminologies used herein are for the purpose of description and should not be regarded as limiting.

We Claim:
1. An indicating mechanism for indicating side of coupling of modular
electric devices adapted to couple from both side, the mechanism comprising:
at least one indication window configured on a casing of the modular electric device;
at least one flag having at least one indicating surface and a protrusion, wherein the protrusion adapted to dispose in a first cavity of a knob, wherein the indicating surface of the flag are visible from the indication window;
a pin disposed in a second cavity of the knob, the slit is disposed on the protrusion thereby enabling sliding of the pin therearound for connecting another modular electric device,
wherein the slit is partially occupied by the protrusion and the remaining portion shows either of the colour strips thereby indicating the side of coupling.
2. The An indicating mechanism as claimed in claim 1, wherein the slit of the pin is provided in the flag.
3. The An indicating mechanism as claimed in claim 1, wherein the protrusion of the flag can be provided in pin interchangeably
4. The An indicating mechanism as claimed in claim 1, wherein the indication surfaces are colour strips painted or stuck or another component/components mounted on it for side indication purpose.