FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
COMPLETE SPECIFICATION (See section 10 and rule 13)
1. TITLE OF THE INVENTION:
Auxiliary Contact Device for Switching 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,
L&T House, Ballard Estate, P. 0. Box: 278, Mumbai 400 001, India
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

Auxiliary Contact Device for Switching Devices
Field of the invention
The present invention relates to an auxiliary contact device and more particularly, to an auxiliary contact device for modular devices for example switching devices.
Background of the invention
Auxiliary contacts devices are the secondary switching devices which work in conjunction with primary switching devices such as circuit breakers, relays and contactors. These contacts are physically linked to the main switching mechanism and activate at the same time as the primary switching devices. They are commonly used as interlocks or retainers on the primary device's control circuit and often used to give remote indication of its state of operation.
Generally auxiliary contacts devices are mounted on a side or bottom of a modular device. These auxiliary contacts devices occupy extra space on a din-rail inside a distribution box and have restriction in the type of termination.
Accordingly, there is a need to provide an auxiliary contact device that overcomes the problems in the prior art.
Objects of the present invention
An object of the present invention is to provide a compact auxiliary contact device that fits on any modular devices and saves the space on a din-rail inside a distribution box.

Yet another object of the present invention is to indicate contact position of a modular device.
Still another object of the present invention is to facilitate termination of the types including but not limited to pin type bus-bar, fork bus-bar (flat and L type), cable termination (rigid and flexible).
Summary of the invention
Accordingly, the present invention provides an auxiliary contact device for a modular/switching device. The auxiliary contact device comprises a first housing/cover, a second housing, a lever, a micro-switch, a box clamp and screw assembly and a stopper assembly. The first housing is secured to the second housing.
The lever extends from a portion between the first housing and the second housing and is capable of inserting in a slot of the switching device thereby mounting the auxiliary contact device to a bottom of the switching device. The'lever is capable of actuating the micro-switch. The lever is pushed and activated by a moving contact of the switching device to actuate the micro-switch. The lever is activated when the moving contact is not in a welded condition that is when the moving contact is in any of an OFF condition and a TRIP condition.
The micro-switch is positioned between the first housing and the second housing. The micro-switch when actuated by the lever occupies any of NO and NC states to indicate contact position of the switching device remotely. The micro-switch is connected to the box clamp and screw assembly by a plurality of connectors. The box clamp and screw assembly allows termination to proceed there from.

The stopper assembly includes a base and a slider. The base is secured to a bottom portion of the second housing for providing support during termination. The termination is selected from any of pin, fork, and cable type of terminations. The slider is connected to the base and adapted to slide with the base to assemble and disassemble with a bus bar for connecting the bus bar to the switching device.
Brief description of the invention
The objectives and advantages of the present invention will become apparent from the following description read in accordance with the accompanying drawings wherein,
Figure 1 shows a perspective view of an auxiliary contact device, in accordance with the present invention;
Figure 2 shows another perspective view of the auxiliary contact device of figure 1;
Figure 3 shows an exploded view of the auxiliary contact device of figure 1;
Figure 4 shows a sectional view of the auxiliary contact device of figure 1;
Figure 5 shows an exploded view of a stopper assembly of the auxiliary contact device of figure 1;
Figure 6 shows a perspective view of the stopper assembly in an assembled state;
Figure 7 shows a perspective view of the stopper assembly with a bus-bar;

Figure 8 shows a perspective view of the stopper assembly without the bus-bar;
Figure 9 shows a perspective view of the auxiliary contact device mounted to a switching device, in accordance with the present invention;
Figure 10 shows a perspective view of the auxiliary contact device mounted to the switching device with the L type bus bar, in accordance with the present invention; and
Figure 11 shows a perspective view of the auxiliary contact device mounted to the switching device with the flat type bus bar. in accordance with an embodiment of the present invention.
Detailed description of the invention
The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiment.
The present invention provides an auxiliary contact device for a switching device. The auxiliary contact device of the present invention fits on any switching device to indicate contact position of the switching device. The auxiliary contact device of the present invention is compact and saves the space on a din-rail inside a distribution box. The auxiliary contact device makes different types of termination possible for the switching device.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures.
Referring now to figures 1-11, there is shown an auxiliary contact device (100) for a modular device such as a switching device (200), in accordance with the present invention. The auxiliary contact device (100) comprises a first housing (10), a second housing (20), a lever (30), a micro-switch (40), a box clamp and screw assembly (50) and a stopper assembly (60). The auxiliary contact device (100) is assembled using any suitable means known in the art.
The first housing (10) acts as a cover of the auxiliary contact device (100). The second housing (20) is secured to the first housing (10). The lever (30) extends from a portion between the first housing (10) and the second housing (20). Specifically, the lever (30) extends from a front central opening (not numbered) between the first housing (10) and the second housing (20). The lever (30) is capable of inserting into a slot (not shown) of the switching device (200). The lever (30) is inserted in the slot in such a way that the auxiliary contact device (100) is mounted to a bottom of the switching device (200).
The lever (30) inside the switching device (200) is activated upon being pushed by a moving contact (not shown) of the switching device (200). Specifically, the lever (30) is activated when the moving contact is in an OFF condition or in a TRIP condition. In other words, the lever (30) activated when the moving contact is not in a welded condition. The lever (30) upon activation causes actuation of the micro-switch (40).

The micro-switch (40) is positioned between the first housing (10) and the second housing (20). The micro-switch (50) is adapted to occupy two types of contact states: NO and NC states depending on the connection configuration. The micro-switch (50) changes the state according to the connection. The micro-switch (40) upon actuation by the lever (30) occupies any of NO and NC states to indicate contact position of the switching device (200). Specifically, the micro-switch (40) gives a remote indication of contact position of the switching device (200). The micro-switch (40) is connected to the box clamp and screw assembly (50).
The box clamp and screw assembly (50) is connected to the micro-switch (30) by a plurality of connectors (45). In an embodiment, the plurality of connectors (45) is a copper strip or wires. The box clamp and screw assembly (50) along with the micro-switch (40) is fitted on a top portion (not numbered) of the second housing (20). The box clamp and screw assembly (50) includes a box clamp (not numbered) and a termination screw (not numbered) for allowing termination to proceed there from.
The stopper assembly (60) is secured to a bottom portion (not numbered) of the second housing (20) using a suitable means known in the art. The stopper assembly (60) includes a base (54) and a slider (54). The base (54) provides support to the auxiliary contact device (100) during termination. The slider (58) is connected to the base (54) (refer to figure 6). The slider (5$) is adapted to slide/to be pushed manually with the base (54) to assemble and disassemble with a bus bar (150) thereby connecting the bus bar (150) to the switching device (200). Specifically, the slider (58) slides in a forward direction to assemble with the bus bar (150) (refer to figure 7). The slider (58) slides in a backward direction to disassemble with the bus bar (150) (refer to figure 7). The bus bar (150) is a pin type bus bar, a fork (flat and L-type), a cable (rigid and flexible) and the like. Thus, the device (100) allows the

switching device (100) to have terminations of pin type, fork (flat and L-type), cable (rigid and flexible) for connection to the bus bar (150).
Advantages of the present invention
1. The auxiliary contact device (100) is compact and occupies less space on the modular/switching device (200) thereby saving the space on the din-rail in the distribution box.
2. The auxiliary contact device (100) is compact and hence capable of fitting at the bottom of any modular device (200) where mechanical actuation is possible.
3. The auxiliary contact device (100) allows flexibility connecting to the modular device (200) where there is no possibility to use conventional auxiliary contacts.
4. The auxiliary contact device (100) is capable of easy mounting at the site depending on the type of termination possible at the end user.
5. The auxiliary contact device (100) facilitates different type's termination such as pin type bus-bar, fork bus-bar (flat and L type), and cable termination (rigid and flexible) in the modular device (200).
6. The stopper assembly (60) of the auxiliary contact device (100) is a multi-level stopper depending on the type of termination and is capable of being adjusted at the site.
7. The auxiliary contact device (100) takes inputs from the moving contact of the modular device (200) and hence indicates true contact position of the modular device (200). This is the true contact indication of the modular device (200) as the auxiliary contact device (100) is not activated in contact welded condition.
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention described in the present embodiment. Detailed descriptions of

the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure, or matter. The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention.

We Claim:
1. An auxiliary contact device (100) for a modular/switching device (200),
the auxiliary contact device (100) comprising:
• a first housing/cover (10);
• a second housing (20) secured to the first housing (10);
• a lever (30) extending from a portion between the first housing (10) and the second housing (20), the lever (30) being capable of inserting in a slot of the switching device (200) thereby mounting the auxiliary contact device (100) to a bottom of the switching device (200);
• a micro-switch (40) positioned between the first housing (10) and the second housing (20), the micro-switch (40) being capable of actuating by the lever (30) for occupying any of NO and NC states to indicate contact position of the switching device (200);
• a box clamp and screw assembly (50) connected to the micro-switch by a plurality of connectors (45) for allowing termination to proceed there from; and
• a stopper assembly (60) having
a base (54) secured to a bottom portion of the second housing (20) for providing support during termination, and
a slider (58) connected to the base (54), the slider (58) adapted to slide with the base (54) to assemble and disassemble with a bus bar (150), the bus bar (150) being capable of connecting to the switching device (200), wherein, a moving contact of the switching device (200) pushes and activates the lever (30) to actuate the micro-switch (40) to indicate contact position of the switching device (200).
2. The auxiliary contact device (100) as claimed in claim 1, wherein the
lever (30) is activated when the moving contact is not in a welded condition.

3. The auxiliary contact device (100) as claimed in claim 1, wherein the
lever (30) is activated when the moving contact is in any of an OFF condition and a TRIP condition.
4. The auxiliary contact device (100) as claimed in claim 1, wherein the micro-switch (40) indicates contact position of the switching device (200) remotely.
5. The auxiliary contact device (100) as claimed in claim 1, wherein the termination is selected from any of pin, fork, and cable type of terminations.