FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003 As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
A hinge assembly for a switchgear enclosure
APPLICANT
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTORS
Shete Shekhar Shashikant, Gadre Parag and Deore Yogesh of Crompton Greaves Ltd., S3 Division, Switchgear Complex, A3 MIDC Ambad, Nashik, Maharashtra, India, all Indian Nationals
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
This invention relates to the field of switchgear enclosures and particularly relates to the construction of the enclosure or housing with respect to the means for locking the door of an enclosure. More particularly, the present invention relates to a hinge assembly for doors on enclosures for electrical apparatus such as switchgears and to such enclosures incorporating the hinge assembly.
BACKGROUND OF THE INVENTION
The enclosures for electrical apparatus, such as for switchgear, include doors Which are used for opening and closing the box containing the mechanism of the circuit breaker. As the box is situated outside, it is exposed to atmosphere and is vulnerable to dust and water. The Ingress Protection (IP) ratings, which are developed by the European Committee for Electro Technical Standardization, specify the environmental protection the enclosure provides. The IP Ratings provide for the protection against solid objects like dust and against liquids.
The enclosures for switchgears known in the prior art comprised of a door fixed to the box, wherein one side of the enclosure was a knob and the other side was a hinge assembly pivotally connecting the said door to the box. The said enclosure, known in the prior art, has a IP Rating of 1P55, signifying that the said enclosure can protect only limited dust ingress and a limited ingress of low pressure jets of water from all directions. The enclosure could not be used in open or under water. The enclosure used a 'D' type of sealing gasket between the box and the door surface, which is compressed between the two surfaces. Since the enclosure used hinges on one side, the compression of the sealing

gasket was non-uniform. There was also a gap in the door; non-uniform gap, resulting in non-uniform pressure in the gasket.
OBJECTIVES OF THE INVENTION
An objective of the invention is to provide an enclosure which could overcome the aforesaid drawbacks.
DETAILED DESCRIPTION OF THE INVENTION
In order to achieve the aforesaid and other objectives, according to the invention, a hinge assembly for switchgear encfosure is disclosed. The enclosure includes a box which houses a circuit breaker, said box having a door openable at one end using a known knob and bracket and hinged at the other end using the hinge assembly, which comprises of a fixed member on the door and a moving member perpendicular to the fixed member. The moving member comprises of at least a nut and threaded portion to accept the nut, such that the movement of the nut on the threaded portion is substantially perpendicular to the fixed member on said door.
These and other aspects, features and advantages of the invention will be better understood with reference to the following detailed description, accompanying drawings and appended claims, in which,
Fig. la illustrates the top view of the enclosure.
Fig. lb illustrates a sectional view of the enclosure taken at A-A.
Fig. lc illustrates an exploded view of the hinge specified as B in Fig lb.

Referring to the figures, the present invention relates to a hinge assembly for a switchgear enclosure, which includes a box (1) housing a circuit breaker (not shown in the figure). The box has a door (2), which is openable at one end using a known knob and bracket (not shown in the figure) and hinged at the other end using said hinge assembly (B). The hinged assembly comprises of a fixed member (4) on the door (2) and a moving member (5) perpendicular to said fixed member. The moving member comprises of at least a nut (6) and threaded portion (7) to accept said nut, such that movement of the nut on the threaded portion is substantially perpendicular to the fixed member on said door. The nut (6) engages the door (2) in order to provide a sealing mechanism. The enclosure described herein has an IP Rating of IP67, signifying that the enclosure disclosed in the present invention totally protects against dust and against the entry of water, if water seeps in even if the enclosure or box is immersed in the water.
Although the invention has been described with reference to a specific embodiment, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiment, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the invention as defined.

We claim:
1. A hinge assembly for a switchgear enclosure including a box housing a circuit breaker, said box having a door openable at one end using a known knob and bracket and hinged at the other end using said hinge assembly comprising of a fixed member on said door and a moving member perpendicular to said fixed member, said moving member comprising of at least a nut and threaded portion to accept said nut, such that movement of said nut on said threaded portion is substantially perpendicular to the fixed member on said door.
2. A hinge assembly as claimed in Claim 1. wherein said nut engages with said door to provide sealing characteristics.