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. - IMPROVED CAGE NUT ASSEMBLY USED IN FIXING ONE STRUCTURAL MEMBER TO ANOTHER.
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 cage nut assembly and more particularly to an improved cage nut assembly used in fixing one structural member to another.
BACKGROUND AND THE PRIOR ART
Cage nut assemblies are well known for provide very useful function. It holds a threaded nut at locations in a frame that are difficult or in some cases impossible to reach with a tool. This access is required at the time a threaded bolt is to be inserted into the nut.
US 6474917 discloses a metal nut (N) held by a plastic clip-body. The clip-body has a first arm, a second arm and an open end that includes a cam section for camming a member into the open end. It also includes an annular locator wall that extends upwardly from the second arm of the clip-body. The upper end of this locator wall is formed to slope upwardly as it extends inwardly from the open end of the clip-body. The sloping upper end of the locator wall helps to cam the member into the clip-body. The first arm has a transverse end section and sidewalls that extend upwardly from the first arm between the end section and the free end of the first arm.
US 5281064 disclose a fastening system that allows the panel mounting of handles and similar hardware in both front and rear mount configurations. A caged bolt is provided in a transverse aperture extending through the hardware item. A mounting bolt includes a head-distal shank portion for engagement with the bolt when inserted through the hardware rear face, and head-proximate unthreaded shank portion for capture by the caged nut when the bolt is inserted through the hardware item from the front face. The caged nut can be positioned along the length of the aperture to align with a panel mounting hole.

US 6146071 disclose an improved cage nut assembly for attachment to a frame, which includes a channel therein adapted to receive the caged nut assembly. The caged nut assembly includes a fastener body having a female connector therein and a retainer for encaging the fastener body. The retainer provides a limited range of movement of the fastener body in at least one direction and has cutouts therein sized and adapted to allow access to the female connector within the range of movement of the fastener body. At least one detent extends from a surface of the retainer, which detents are sized and shaped to correspond to at least one notch in the channel of the frame. The detents are biased toward a normal position, but are movable against the bias such that as the caged nut assembly is forced into the channel of the frame, the detents are moved against the bias until the detents are positioned adjacent to the notches in the channel, at which point the detents are biased into the notches, thereby securing the caged nut assembly within the channel. Thus, during a crash situation, the detents may be moved against the bias and the caged nut assembly may be moved within the channel in the frame.
US 6644902 disclose a cage-nut assembly includes a nut positioned within a cage structure. The cage structure is configured to provide high torsion strength to prevent rotation of the nut. The cage structure has a flat base and an at least partially open end portion. The cage structure includes a blocking member preventing the nut from moving laterally along the base through the at least partially open end portion. The blocking member is relatively structurally weak in a direction orthogonal to a torsion rotation direction of the nut. The structurally weak blocking member is bendable when less than approximately 20 lbs. of force is applied to the blocking member to open the end portion and allow the nut to move laterally along the base through the end portion for removal of the nut.
US 6811363 disclose a floating and captured cage nut assembly includes a structural member that is U-shaped with a pair of rolled sides defining mounting legs and a

rolled front end defining an anti-rotation flange. The rolled sides of the structural member are positioned on the component and are welded or otherwise secured thereto over the opening during manufacture. The floating and captured cage nut assembly further includes an anti-rotation plate having a hexagonal opening to receive a flange nut and a locking window. The anti-rotation plate and the flange nut are inserted within the structural member and the anti-rotation flange is received within the locking window with clearance to loosely secure the components together. The flange nut is retained on the component, and the anti-rotation plate prevents its rotation. The clearance between the anti-rotation flange and the locking window facilitates the threading of the fastener into the nut within a predetermined tolerance zone.
US 6854941 disclose a clip nut is provided having a plastic body holding captive a nut. The body includes two aligned arms projecting from an aft section, each arm defining an aperture at a forward portion of the arm. The nut includes a base and a upstanding portion extending from the base that defines an internally threaded bore. The body further includes a nut cage positioned disposed about the aperture of the first arm. The nut cage includes an upper wall spaced above the first arm that defines a slot having a narrowed inlet and a recess aligned with the apertures of the first and second arms. The body is configured to readily and securely receive the nut. To insert the nut into the cage, the nut is forced against the nut cage such that the upstanding portion presses into and past the narrowed inlet. In this manner, the cage yield receives the nut without undue manipulation of either piece.
The disadvantages of the existing assembly is loosening and falling out of nut from the frame assembly because of softness of material of cage nut assembly and the same can not be hardened because of their typical construction.
Thus, there is a need to overcome the problems of the prior art. The present invention therefore provides an improved cage nut assembly which would be used in fixing one

structural member to another member and would provide flexibility to the frame fixing where the access is difficult to hold the bolt and nut simultaneously.
OBJECTS OF THE INVENTION
A basic object of the present invention is to overcome the disadvantages/drawbacks of the known art.
Another object of the present invention is to provide an improved cage nut assembly used in fixing one structural member to another.
Another object of the present invention is to provide proper engagement of retainer
fastener within frame.
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 cage nut assembly used in fixing one structural member to another.
According to one embodiment of the present invention, there is provided cage nut assembly comprising a retainer cage comprising a bent profile for trapping a fastener, a slot for anti-rotation of said nut; and a duality of projections for firm fixing of said assembly.

Other embodiment of the present invention provides resting surface as well as projections for trapping the said fastener.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig 1 illustrates retainer cage and a fastener.
Fig 2 & 3 illustrates exploded view of the arrangement showing each block separately.
Fig 4, 5 & 6 illustrates different views of retainer cage
Fig 7 & 8 illustrates different views of sheet metal blank used for making retainer cage.
Fig 9, 10 & 11 illustrates different view of improved cage nut assembly.
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 retainer cage nut assembly is shown. It comprises a retainer cage and a fastener.

Fig. 2 & 3 shows different components separately. It shows retainer cage and fastener.
Fig. 4, 5 & 6 shows different constructional features. It shows bent profile for traping the nut, hexagonal slot, wedge shaped projections etc.
Fig. 7 & 8 shows the sheet metal blank with different views. The retainer cage is made out from a single sheet metal.
Fig. 9, 10 & 11 shows the assembly of an improved cage nut assembly used in fixing one structural member to another. It shows different view for the cage unit.
The invented system is thus an improved cage nut assembly used in fixing one structural member to another.
DETAILED DESCRIPTION OF THE INVENTION
Accordingly the present invention provides an improved cage nut assembly for perfect and proper engagement of a retainer fastener within structural frame member. The cage structure is configured to provide high torsion strength to prevent rotation of the nut.
The present invention makes assembly of frames / structural members simpler because of self alignment feature and anti-rotation feature. The firm fixing of this cage nut assembly is achieved using the wage shaped protrusion. This helps in positive engagement of this cage nut assembly with the structural frame member. The removal of this assembly from the frame will require a mechanical effort with the tool, so falling of this nut assembly is avoided due to any gravitational forces or vibration forces.

Due to variations in manufacturing tolerances, a degree of position adjustment for the female fastener like nut must be provided so that two fixing members/frames may be properly aligned during final assembly. The disadvantage of loosening and falling out from the frame assembly because of softness of material of the prior art has been taken care in this invention by hardening the sheet steel material of cage and then making an assembly with nut.
According to a preferred embodiment of the invention, there is provided an improved cage nut assembly. As shown in figure 1, Retainer Cage Nut Assembly comprises two parts such as Part 1 (Retainer Cage) and Part 2 (Fastener like Nut). Figures 2 and 3 show an exploded view of Part 1 and Part 2. A retainer cage is shown in figures 4, 5 and 6 which comprises features such as a bent profile (1a) for trapping the nut, Hexagonal slot (lb) for anti-rotation of hex nut as fastener, three flat surfaces (opposite to each other) of slot are fully hexagonal in shape which act as a resting surfaces for nut (1c), and another three surfaces are raised as a special projection to trap the nut in place (ld).This special shape is made by forming tool. There are two wedge shaped projections (1e) on either side for firm fixing of assembly into the frame. This will avoid falling of the assembly. The required strength is achieved by hardening the formed cage
Figures 7 and 8 show a sheet metal blank, which is for making the said retainer cage. It is made out of a single sheet. The appropriate cuts/slots/projections/forming are done to achieve the above mentioned features. Figures 9, 10 and 11 show the final assembly of the said retainer cage assembly and structural frame member. It consists of the following features such as the representative structural member, like Frame, Channel, Beam, Cross-piece, connector, etc... (3a) and the retainer cage assembly of Figure 1 (3b).

The functioning of the assembly is such that in the first step, insert the part 1 in Part 2 by slightly raising the Z-shaped bent surface of Part 2 as shown in figures 2 and 3. In the second step, Part 1 gets trapped inside the part 2 as shown in figure 1. The orientation of part 1 is properly mated with hexagonal surfaces of part 2. In the third step, assembly of Part 1 and Part 2 (3b) as shown in Figures 9, 10 and 11 is done with 3a. This will securely fasten the said retainer cage assembly (3b) into the structural member (3a).
ADVANTAGES
a) Perfect & Proper engagement of this retainer fastener within structural frame member.
b) High torsion strength of a cage structure.
c) Assembly of frames / structural members simpler because of self alignment feature and anti-rotation feature.
d) Ease of Assembly of nut into the cage.
e) The cage can be formed from a single sheet of steel.
f) Special forming is done to retain the nut in place.
g) Nut has a limited range of movement within the cage.
h) Wedges are provided to firmly secure the cage on the frame structure.
i) The base sheet steel material is hardened first and then the nut is inserted into
the cage. This gives more strength and longer life to an assembly, j) Flexibility to absorb the tolerances in "X" and "Y" planes, k) The hardening of cage can be carried out at the raw material stage or at
the formed component stage. 1) The falling of this nut assembly is avoided against any gravitational
forces or vibration forces.
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 cage nut assembly used for fixing one structural member to
another, said cage nut assembly comprising:
a retainer cage comprising a substantially bent profile for trapping a fastener,
a slot for anti-rotation of said nut; and
a duality of projections for firm fixing of said assembly.
2. Improved cage nut assembly as claimed in claim 1 wherein said slot is polygonal.
3. Improved cage nut assembly as claimed in claims 1 and 2 wherein said slot is hexagonal.
4. Improved cage nut assembly as claimed in claims 1 to 3 wherein said slot comprising three projected surfaces for trapping said nut.
5. Improved cage nut assembly as claimed in claim 1 wherein said retainer cage is made out of a single sheet.
6. An improved cage nut assembly used in fixing one structural member to another as herein substantially described and illustrated with reference to the accompanying drawings.