FORM 2
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 ARRANGEMENT OF SAFETY
SHUTTER AT TERMINATION IN MODULAR DEVICES
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
This invention relates generally to a modular switchgear devices and more particularly to an improved arrangement of safety shutter at termination in modular switchgear devices.
BACKGROUND AND THE PRIOR ART
Modular switchgear devices mainly consists of circuit breakers in which the height of the front face is not more than 45mm. This is because front face can come out easily from the slots in Distribution Boards for easy access for its operation. Modular circuit breaker comprises Miniature Circuit Breaker, Residual Current Circuit Breaker, Earth Leakage Circuit Breaker, Isolator, RCBO. Undervoltage release, Overvoltage release etc.
It has been found that in modular devices, the moment the terminal screw is tightened, box clamp moves up which creates a blind gap at the bottom of box clamp. Now if any one tries to put the wire in the device facing front side, he or she can put the wire in that blind gap because the top cannot be seen from front side of the panel. This can lead to lose electrical connection of wire to the device which is not advisable from safety perspective.
To avoid the wire from entering the blind gap, safety shutter is provided behind the terminal which occupies the blind gap developed when terminal screw is tightened.
Till now, solid inflexible part is used as a safety shutter behind the terminal in modular switchgear devices.

JP2010225445 discloses a circuit breaker for easily and safely carrying out connection and removal of an external connection line of a main circuit terminal, and further screwing work of terminal screws, even with the external connection line connected to an attachment terminal of an attachment circuit. However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
KR20080093973 (A) discloses a fault-current circuit breaker comprising a housing with at least one clamping opening and/or at least one clamping screw opening. The aim of the invention is to reduce the costs of manufacture and storage of such a switchgear. For this purpose, a locking element, preferably comprising an insulating material, is arranged in the clamping screw opening and at least partially fills the clamping screw opening. However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
JP2009272149 (A) discloses
terminal cover-mounting structure of a circuit breaker, which is improved so that: a terminal cover mounted to the mold case of the circuit breaker can be firmly fixed by fastening a screw while conforming to new safety standards; and reliability of a screw fastening function can be also improved besides improvement of work efficiency for detaching the terminal cover, regardless of whether the circuit breaker is new or old. However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
DE10340465 (Al) discloses a connecting terminal which fits inside a switchgear casing near a narrow side. In a terminal mounting, a retaining area (RA) is accessible from outside to clamp on connecting conductors. The RA fits between a bottom transverse link and a link moved by an adjusting screw (18). A terminal box covering

part (1) has two legs (100,200) at right angles to each other. However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
FR2556124 (Al) discloses a Covering element for uncovered terminals of a switch which are operated by screws, in particular for line-safety breakers, which includes a bent part made of an insulating material, kept level with the head of the screw of the terminal and covering the uncovered portion of the terminal, characterised in that the bent part made of an insulating material includes appended portions in the form of plates, which grasp the screw head laterally and, after being pushed perpendicularly to the direction of the axis of the terminal screw , are held there by automatic tightening, and is engaged, virtually without play, by a projection made on the wing of the bent part which is almost parallel to the terminal screw and covers the outside of a fixed pressure clamp , in an opening in the pressure clamp, so that only an uncovered terminal housing which has to be manoeuvred by way of the terminal screw may move in the longitudinal direction. However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
US6172586 discloses a circuit breaker including a terminal barrier system. The terminal barrier system includes a terminal barrier attached to a circuit breaker base at the terminals, line and load, of the breaker and a terminal connector mounted in the terminal barrier to align with a terminal of the breaker. Several embodiments of the terminal barrier and terminal connector are provided which allow flexibility in combining the various terminal barriers and terminal connectors for a given current rating of the breaker. The terminal barrier system protects the terminals of the circuit breaker during short circuit condition operations, prevents pole to pole electrification and prevents accidental contact with live electrical wires in the contacts. The circuit breaker also includes a molded case, a first and second terminal mounted in the case,

the first contact electrically coupled to the first terminal and a second contact electrically coupled to the second terminal . An operating mechanism having a pivoting member movable between an ON position and OFF position and a TRIPPED position is coupled to the second contact. An intermediate latch mechanism mounted in the housing is coupled to the operating mechanism and is selectively operated by a trip unit coupled to the second contact and the second terminal. An electric arc extinguishing apparatus is mounted in the housing and positioned in confronting relation with the first and second contact.
However, it doesn't talks about the flexible insulation part used as a safety shutter at terminal which can be accommodated in lesser space.
OBJECTS OF THE INVENTION
A basic object of the present invention is to overcome the disadvantages/drawbacks
of the known art
If safety shutter is in the form of solid inflexible part, it requires more space behind
the terminal for its movement. Thus there is a need to provide for an improved
arrangement of safety shutter at termination for addressing the existing problem.
The object of the invention is to minimize the space requirement of safety shutter
behind the terminal. This innovative flexible safety shutter can be accommodated in
less space available behind the terminal.
Another object of this invention is to reduce the part cost & implementation cost.
Since the thickness requirement of an insulating piece is less, in order to achieve
flexibility, and also process of punch press will be used instead of moulding, it will
be cheaper to implement this innovative design of safety shutter.
Yet another object of the present invention is to provide a method of providing safety
using a safety shutter at termination in modular devices

Another object of the present invention is to provide an improved arrangement of
safety shutter at termination in modular devices.
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 arrangement of safety shutter at termination in modular devices.
According to one embodiment of the present invention, there is provided an improved arrangement of safety shutter at termination in modular devices, said safety shutter comprising an insulation paper strip placed over a box clamp; movement of said insulation paper strip guided by a slot provided in housing and cover; said shutter covering a gap below said box clamp.
Other embodiment of the present invention provides a method of providing safety using a safety shutter at termination in modular devices comprising the steps of tightening the screw resulting in lifting of box clamp, said box clamp taking insulation paper strip along with; movement of said insulation paper strip guided by a slot provided in both housing and cover.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 illustrates a modular device without a safety shutter. Figure 2 illustrates a safety shutter in rectangular box.

Figure 3 illustrates the internal arrangement of safety shutter in the switch.
Figure 4 illustrates the steps of folding of pre-cut Insulation Paper to form a Safety Shutter arrangement.
Figure 5 illustrates the exploded view of terminal assembly with safety shutter.
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 a modular device without a safety shutter is shown. It shows termination window easily accessible from outside.
Fig. 2 shows a safety shutter in a rectangular box. Gap below the box clamp is fitted with a safety gear.
Fig. 3 shows internal arrangement of safety shutter in the switch. It shows fixing of shutter with box clamp.
Fig. 4 shows the steps of folding of pre-cut Insulation Paper to form a Safety Shutter arrangement.
Fig. 5 shows the exploded view of terminal assembly with safety shutter. It shows safety shutter, box clamp, terminal screw etc.
The invented system is thus an improved arrangement of safety shutter at termination in modular devices.

DETAILED DESCRIPTION OF THE INVENTION
Accordingly in the present invention an Insulation paper strip arrangement of small thickness is provided which will act as a shutter at termination when box clamp lifts while tightening the screw. This Insulation paper strip arrangement is having a zigzag shape which gives strength to it while movement. Insulation paper strip arrangement is put over the Box Clamp. The moment a screw is tightened, this box clamp lifts which takes Insulation paper strip arrangement along with it. The movement of Insulation paper is guided by means of a slot provided in both housing and cover.
This shutter covers the gap which doesn't allow anyone to insert a wire in the gap below to box clamp. Following are the parts which are used in the assembly of safety shutter:
1) Housing
2) Cover
3) Safety Shutter
4) Box Clamp
5) Terminal Screw
There are some images which will describe the whole operation of safety shutter.
Figure 1) shows a modular device without a safety shutter. In this it is clearly visible that in on condition the termination window (Shown in rectangular Box) is easily accessible from outside. By mistake anyone can put wire in this blind gap. In this invention we will cover this gap with the help of safety shutter to remove the accessibility of this gap from outside.
In fig 2) a safety shutter in rectangular box can be seen. From the above figure it is clearly visible that now the gap below to box clamp is filled by safety shutter in ON condition. Now by mistake if anyone tries to access this gap from outside there will be an interference with safety shutter, which will make him realize the presence of

safety shutter. So he will remove the wire from this module and will put the wire in the intended module.
Fig 3) shows the internal arrangement of safety shutter in the switch. In the above figure cover is removed to see the arrangement. Here the fixing of shutter with box clamp can be seen. Fig 4) shows the steps of folding of pre-cut Insulation Paper to form a Safety Shutter arrangement. Fig 5) is the exploded view of terminal assembly with safety shutter.
The arrangement can be used in domestic and industrial applications, applications where modular devices are used and the like.
Advantages:
• It is a cost effective solution
• Assembly is much easier
• It can assemble in switch without any change in some other part.
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 arrangement of safety shutter at termination in modular devices,
said safety shutter comprising:
an insulation paper strip placed over a box clamp; movement of said insulation paper strip guided by a slot provided in housing and cover; said shutter covering a gap below said box clamp.
2. Improved arrangement of safety shutter as claimed in claim 1 wherein said insulation paper strip is substantially zig-zag shape.
3. A method of providing safety using a safety shutter at termination in modular devices comprising the steps of tightening the screw resulting in lifting of box clamp, said box clamp taking insulation paper strip along with; movement of said insulation paper strip guided by a slot provided in both housing and cover.
4. Method as claimed in claim 4 wherein said safety shutter covers the gap below to said box clamp.
5. An improved arrangement of safety shutter at termination in modular devices as herein described and illustrated with reference to the accompanying drawings.

6. A method of providing safety using a safety shutter at termination in modular devices as herein described and illustrated with reference to the accompanying drawings.

1. Title of the invention: AN IMPROVED ARRANGEMENT OF SAFETY SHUTTER AT TERMINATION IN MODULAR DEVICES

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 describes the invention

Field of the invention

The present invention relates to an improved arrangement of safety shutter at termination in modular devices. The arrangement can be used in domestic and industrial applications, applications where modular devices are used and the like.

Background of the invention

In Modular devices the moment the terminal screw is tightened, box clamp moves up which creates a blind gap at the bottom of box clamp. Now if any one tries to put the wire in the device facing front side, he or she can put the wire in that blind gap because the top cannot be seen from front side of the panel. This can lead to loose electrical connection of wire to the device which is not advisable from safety perspective.

Thus there is a need to provide for an improved arrangement of safety shutter at termination for addressing the existing problem.

Objects of the invention

One object of the present invention is to overcome the drawbacks/disadvantages of the prior art.

A basic object of the present invention is to provide an improved arrangement of safety shutter at termination in modular devices.

As described above, in this invention we are providing a safety shutter solution in modular devices. The technical specifications and other assembly details are as following.

Brief description of the accompanying drawings

Figure 1 shows a modular device without a safety shutter.

Figure 2 shows a safety shutter in rectangular box.

Figure 3 shows the internal arrangement of safety shutter in the switch.

Figure 4 shows the steps of folding of pre-cut Nomex.Paper to form a Safety Shutter arrangement.

Figure 5 is the exploded view of terminal assembly with safety shutter.

Detailed description of the accompanying drawings

In the present invention an Insulation (Nomex) paper strip arrangement of 0.25mm thickness is provided which will act as a shutter at termination when box clamp lifts while tightening the screw. This Insulation paper strip arrangement is having a zig- zag shape which gives strength to it while movement. Insulation paper strip arrangement is put over the Box Clamp. The moment a screw is tightened, this box clamp lifts which takes Insulation paper strip arrangement along with it. The movement of Insulation paper is guided by means of a slot provided in both housing and cover.

This shutter covers the gap which doesn’t allow anyone to insert a wire in the gap below to box clamp.

Following are the parts which are used in the assembly of safety shutter:

1) Housing
2) Cover
3) Safety Shutter
4) Box Clamp
5) Terminal Screw

There are some images which will describe the whole operation of safety shutter.

Figure 1) shows a modular device without a safety shutter. In this it is clearly visible that in on condition the termination window (Shown in rectangular Box) is easily accessible from outside. By mistake anyone can put wire in this blind gap. In this invention we will cover this gap with the help of safety shutter to remove the accessibility of this gap from outside.

In fig 2) a safety shutter in rectangular box can be seen. From the above figure it is clearly visible that now the gap below to box clamp is filled by safety shutter in ON condition. Now by mistake if anyone tries to access this gap from outside there will be an interference with safety shutter, which will make him realize the presence of safety shutter. So he will remove the wire from this module and will put the wire in the intended module.

Fig 3) shows the internal arrangement of safety shutter in the switch. In the above figure cover is removed to see the arrangement. Here the fixing of shutter (Nomex Paper) with box clamp can be seen.

Fig 4) shows the steps of folding of pre-cut Nomex.Paper to form a Safety Shutter arrangement.

Fig 5) is the exploded view of terminal assembly with safety shutter.

Advantages :

• It is a cost effective solution
• Assembly is much easier
• It can assemble in switch without any change in some other part.