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 device for locating an electrical contact strip into a grooved surface of an object
APPLICANT
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTOR
Kulthe Sunil R of Crompton Greaves Ltd, S3, R&D Division, Nasik, Maharashtra, India, an Indian National
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 a device for locating an electrical contact strip into a grooved surface of an object and more particularly to a device for locating an electrical contact strip into a grooved inner surface of a stationary contact holder of a stationary contact assembly in a high voltage gas circuit breaker. BACKGROUND OF THE INVENTION
Electrical contact strip, such as a Multilam® (Multi-Electrical Ag, Switzerland) contact, is used as an electrical connector between stationary and moving contact of a high voltage gas circuit breaker. The electrical contact strip is inserted into a groove provided on an inner surface of a stationary contact holder of a stationary contact assembly. Usually, the electrical contact strip is inserted into the groove manually. A first end of the electrical contact strip is first pushed inside the grooved surface through a slightly widened spot on the grooved surface. Thereafter, the remaining part of the electrical contact strip is pushed manually inside the grooved surface until the second end of the electrical contact strip is received inside the grooved surface. At regular intervals, dabbing of the electrical contact strip inside the grooved surface is required due to uneven pushing to ensure that the electrical contact strip remains inside the grooved surface.
Manual insertion of the electrical contact strip and locating thereof inside the grooved surface is laborious, time consuming and inefficient. This also usually involves more than one skilled person. Moreover, there is a constant risk of damaging the electrical contact strip which is usually very expensive. Injury to the fingers of the person performing the above is also common.

DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a device for locating an electrical contact strip into a grooved surface of an object, the device comprising a frame having a top surface and a first and second wall extending therefrom in a spaced apart relationship with each other and a locking pin extending into the space between the first and second walls through the first wall, wherein the frame being configured on the object such that the grooved surface of the object faces an inner surface of the first wall, the frame being adapted to move on the object smoothly during said configuration, the locking pin being adapted to be selectively locked with a first end of the electrical contact strip pushed inside the grooved surface manually such that upon moving the frame on the object, the first end of the electrical contact strip being dragged forward in the grooved surface thereby pulling the remaining portion of the electrical contact strip into the grooved surface including the second end of the electrical contact strip.
According to a preferred embodiment, the object is a stationary contact holder of a stationary contact assembly in a high voltage gas circuit breaker and the electrical contact strip is a Multilam® (Multi-Electrical Ag, Switzerland) contact strip.
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 1 is an isometric view of a device for locating an electrical contact strip into a grooved surface of an object.
Fig 2 is an exploded view of a device for locating an electrical contact strip into a grooved surface of an object.

Fig 3a, 3b and 3c illustrates the application of a device for locating an electrical contact strip into a grooved surface of an object.
Figs 1 and 2 are respectively an isometric and exploded view of a device for locating an electrical contact strip inside a grooved surface of an object. According to a preferred embodiment, the electrical contact strip is a Multilam® (Multi-Electrical Ag, Switzerland). However, there may be used any type/brand of electrical contact strip (referred to as contact strip 9 hereafter). The object according to the preferred embodiment is a cylindrical stationary contact holder 10 of a stationary contact assembly of a high voltage gas circuit breaker. An inner surface 11 of the stationary contact holder 10 is provided with a groove 12 of a shape and size corresponding to the shape and size of contact strip 9. The length of the contact strip 9 corresponds to the circumference of the inner surface 11 of the stationary contact holder 10. The device according to a preferred embodiment comprises of a frame having a pair of walls (first 1 and second 2 wall) extending from a flat top surface 3 of the frame. The frame is configured on the stationary contact holder 10 such that the top surface 3 rests on a top edge 13 of the stationary contact holder 10 and the grooved inner surface 11 of the stationary contact holder 10 faces an inner surface 4 of the first wall 1. The frame is arc shaped for accommodating circular portions of the stationary contact holder 10 in the space between the walls 1 & 2. Two rows of three adjacent slots are provided in the first wall 1 of the frame for holding rollers 5 therein. The rollers 5 are held within the respective slots by means of a holding pin 6 extending vertically into the wall thickness through the center of slots. In the above stated configuration of the frame on the stationary contact holder 10, the rollers 5 on the first 1 and second 2 walls remain in contact with the inner surface 11 and outer surface of the stationary contact holder 10 respectively. Further, a locking pin 7 is provided

extending into the space between the first 1 and second 2 walls through the center of the first wall 1. The locking pin 7 is preferably made of rubber material and a first end 8 thereof disposed between the space of the walls 1 & 2 has a teethy surface corresponding to the shape of the contact strip 9 so as to be lockingly engaged therewith upon pushing (by a user) of the locking pin 7 against the contact strip 9.
Fig 3a, 3b and 3c illustrates the application of the device. As shown in Fig 3a (sectional isometric view of the stationary contact holder), a first end of the contact strip 9 is manually inserted into the grooved inner surface 11 through a widened spot (not shown) thereupon. Thereafter, the frame is configured on the stationary contact holder ] 0 such that the top surface 3 of the frame rests on the top edge ] 3 of the stationary contact holder 10 and the grooved inner surface 11 of the stationary contact holder 10 faces the inner surface 4 of the first wall 1. The frame is adjusted on the stationary contact holder 10 such that the first end 8 of the locking pin 7 faces the first end of the contact strip 9. The locking pin 7 is then pushed against the contact strip 7 such that the first end 8 of the locking pin 7 and the contact strip 9 are locked together. Thereafter, the frame is pushed forward on the top edge 13 of the stationary contact holder 10 along the grooved inner surface 11. Rollers 5 facilitate smooth movement of the frame on the stationary contact holder 10. As the frame moves forward, the first end of the electrical contact strip 9 too gets dragged forward into the grooved inner surface 11 along with the frame (on account of it being locked with the locking pin of the frame). Consequently, the remaining part of the contact strip 9 outside the grooved inner surface 11 too gets sucked inside the grooved inner surface 11. As shown in fig 3b. pushing of the frame is continued until the second end 14 of the contact strip is received inside the grooved inner surface 11. Once the entire contact strip 9 is located inside the grooved inner surface 11, the locking pin 7 is

pulled to disengage its first end 8 from the first end of the contact strip 9. The frame is then removed off the stationary contact holder 10 as shown in fig 3c.
According to a preferred embodiment, an alignment pin 15 extends through the center of the second wall 2 of the frame into the space between the first 1 and second 2 walls. In the aforementioned configuration of placement of the frame on the stationary contact holder 10, a first end 16 of the alignment pin 15 is disposed in the space of the first 1 and second 2 walls and faces the outer surface of the stationary contact holder 10. Before the frame is being pushed forward on the top edge of the stationary contact holder, the alignment pin is positioned such that its first end maintains a small distance from the outer surface of the stationary contact holder. This is to ensure that the space between the inner surfaces of the walls and the corresponding opposite surfaces of the stationary contact holder does not increase beyond a tolerance limit. This tolerance limit is equivalent to the space between the first end 16 of the alignment pin 15 and the outer surface of the stationary contact holder 10. This ensures that the first end 8 of locking pin 7 is not pulled outwardly (thereby disengaging itself with the first end of the locking strip) while the frame moves inwardly during pushing thereof forwardly on the top edge 13 of the stationary contact holder 10.
It will be obvious to a person skilled in the art that appropriate modifications can be carried out in the device depending upon the object on which the device is intended to be used. For example, the shape of the frame may vary depending on the shape of the object and may not necessarily be arc shaped. There may be means other than rollers as described above to adapt the frame to be moved smoothly on the object. The rollers itself may be held in some other fashion instead of a holding pin. The locking pin and alignment pin may not necessarily be made up of rubber material.

Even though the frame is made of up of metal according to the preferred embodiment. it may not be necessarily so. The teethy surface of the first end of the locking pin is only intended to form a locking arrangement between the first ends of locking pin and the contact strip and there may be other shapes for achieving the same result. Although, the frame is designed to be pushed forward manually on the object, there may be means attached to the frame to move the frame on the object automatically or semi-automatically. Similarly, there may also be semi-automatic or automatic means configured with the locking pin to lock/unlock thereof with the contact strip.
According to the invention, there is provided a device which eliminates a substantial amount of manual labour involved in locating the electrical contact strip into a grooved surface of the object. Consequently, locating of the electrical contact strip in the grooved inner surface of an object is faster and hassle free. Also, instances of the electrical contact strip being damaged and the person locating the electrical contact strip getting injured during locating is eliminated substantially.
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 scope of the invention as defined in the appended claims.

We claim:
1. A device for locating an electrical contact strip into a grooved surface of an object, the device comprising a frame having a top surface and a first and second wall extending therefrom in a spaced apart relationship with each other and a locking pin extending into the space between the first and second walls through the first wall, wherein the frame being configured on the object such that the grooved surface of the object faces an inner surface of the first wall, the frame being adapted to move on the object smoothly during said configuration, the locking pin being adapted to be selectively locked with a first end of the electrical contact strip pushed inside the grooved surface manually such that upon moving the frame on the object, the first end of the electrical contact strip being dragged forward in the grooved surface thereby pulling the remaining portion of the electrical contact strip into the grooved surface including the second end of the electrical contact strip.
2. A device as claimed in claim 1, wherein the electrical contact strip is a Multilam contact strip.
3. A device as claimed in claim 1, wherein the object is a cylindrical stationary contact holder of a high voltage circuit breaker, the groove being provided on the inner circular surface of the stationary contact holder.
4. A device as claimed in claim 3, wherein the frame is arc shaped to accommodate the circular wall of the stationary contact holder within the space between the first and second walls of the frame.
5. A device as claimed in claim 1, wherein a plurality of rollers are provided on one or both walls of the frame such that the frame when placed on the object

the rollers being in contact with the object for facilitating smooth movement of the frame on the object.
6. A device as claimed in claim 1, wherein the end of the locking pin disposed between the first and second walls is provided with a teethy surface formed of rubber material for engaging and locking thereof with the first end of the electrical contact strip.
7. A device as claimed in claim 1, wherein an alignment pin extends through the center of a second wall of the frame into the space between the first and second walls such that during said configuration of the frame on the object, an end of the alignment pin disposed between the spaces of the walls faces the outer surface of the object and is in a predetermined spaced apart relationship therewith.