Field of the Invention

This invention generally relates to provide a floating male fastener within the profile of an entity to fasten another entity by coupling a nut with the said floating male fastener where nut fastener is used for fastening with a screw

Background

Telecommunication circuit networks essentially consist of electronic devices arranged in a system. This system provides for a front panel consisting of a face plate, Printed Circuit Board (PCB), card cage and a latch mechanism on either side of the face plate to fasten the front panel with the chassis. The face plate area through the openings is the access point to the services offered by the PCB. The front panel with the PCB is guided by a card cage to attach the PCB with the back plane of the system. To firmly secure the front panel with the card guide attached to the chassis, a screw nut mechanism is provided on its either sides. The major consideration is fixing the screw with the nut axis in effective alignment with the axis of the screw. This offset caused an assembly issue when the card is assembled to the chassis. Further repeated Jack-in and Jack-out of the front panel from the card cage and re-fixing the screw with the nut in spite of this offset damages the card guide as well as the face plate and renders it unfit for further use. Moreover, the distance between the two nuts of the respective card guides fails to maintain any tolerance so as to align the screw axis with the nut axis because in manufacturing it is difficult to maintain the pitch within 0.2 mm tolerance as lot of assemblies are involved. Another solution would be to use a standard floating nut. The limitation in the standard floating nut is that the nuts require a minimum card guide width of 17.6 mm. Therefore a viable solution would be to provide a floating male fastener instead of a floating nut on the card guide such that the male fastener's head, its depth, its width can be customised to suit the mounting space on the card guide.

Summary of the invention

An aspect of the present invention is to address at least the above mentioned problems or disadvantages and to provide the advantages as below:

Accordingly an aspect of the present invention is to provide a floating male fastener within the profile of an entity. The floating male fastener is provided with one or more obstructions integrally and external to it and in one such embodiment the obstruction is provided by riveting the male fastener to a piece of sheet metal which would be later assembled within the profile of the card guide. This sheet of metal housing the male fastener has protrusions in plurality of shapes and in one embodiment of the invention the shape includes a rectangle, projecting like wings at its either sides which is placed into small rectangular slots provided on either side within the profile of the card guide. The embodiments of the invention provide for appropriate slots matching the shape of the protrusion within the profile of the card guide. The floating movement of the male fastener is caused by providing one or more obstructions integral with and external to the male fastener such that the movement of the obstructions with other entity is limited along its rotational and linear movement.

Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

Brief description of the drawings

The features, advantages and other aspects of the embodiments of the present invention will be obvious to any person skilled in the art to appreciate the invention when read with the following description taken in conjunction with the accompanying drawings.

FIG 1 shows an isometric view of the male fastener in accordance with the principles of the present invention.

FIG 2 shows an isometric rear view of the card guide in accordance with the embodiments of the present invention.

FIG 3 shows an isometric rear view of the male fastener mounted on the respective slot on the card guide in accordance with the principles of the present invention.

FIG 4 shows the assembling sequence of the male fastener with the card guide in accordance with the embodiments of the present invention.

FIG 5 shows the front view of the card guide engaged with the male fastener in accordance with the embodiments of the present invention.

FIG 6a shows the assembly sequence of the male fastener in accordance with one aspect of the present invention.

FIG 6b shows an isometric view of the male fastener in accordance with one aspect of the present invention.

FIG 6c shows an isometric view of the male fastener in accordance with another aspect of the present invention.

FIG 7 shows a lateral side view of the male fastener in accordance with one aspect of the present invention.

FIG 8 shows the cross-sectional top view of the male fastener in accordance with one aspect of the present invention.

The figures are not drawn to scale and are illustrated for simplicity and clarity to help understand the various embodiments of the present invention. Throughout the drawings it should be noted that like reference numbers are used to depict the same or similar elements, features and structures.

Detail description of the Invention

The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

Figs. 1 to 8 discussed below and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way that would limit the scope of the disclosure.
Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged systems. The terms used to describe various embodiments are exemplary. It should be understood that these are provided to merely aid the understanding of the description, and that their use and definitions in no way limit the scope of the invention.

Any term specifically reciting some of the present invention's characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the present invention was intended to provide.

Figure 1 depicts the floating nut 12 in accordance with the embodiments of the present invention. In an embodiment of the invention a metal sheet 10 is customised to form a structure as shown in figure 1 with its body 10b having rectangular protrusions 10c on its both horizontal ends. The top vertical end surface 10e of the metal sheet 10 is flat which is followed by two adjacent inclined surfaces 10d on its either sides. Similar symmetrical shape encompasses the bottom surface (as shown partially in figure 1). The ends of the inclined surface 10f are bent perpendicularly towards the protrusion 10c such that the protrusion with its adjacent sides 10g resemble a rectangular flap having as its sides 10g along its length and 10h along its breadth. Through the metal sheet structure 10, a cylindrical threaded projection 11 is riveted through the body of the metal sheet 10b such that the maximum area 10b of the metal sheet is enclosed by the cylindrical projection 11. The cylindrical threaded projection 11 and its circumference 11a is of specified dimension so as to suit its varied applications. The cylindrical threaded projection 11 riveted with the metal sheet 10 comprises to form a male fastener 12 with its axis along 11b.

Figure 2 depicts a portion of the card guide frame 20 in accordance with the embodiments of the present invention. The card guide 20 is a C-shaped rectangular metal frame with its side 20b along its breadth having openings 20f at regular intervals. The side 20a, bent backwards perpendicular to the side 20b, is projected to a determined length. The top layer of the projected length is provided with slots 20d at regular intervals exactly coinciding with the openings 20f on the side 20b. The side 20g which is bent backwards perpendicular to the side 20b and parallel to the side 20a is an elongated metal frame which guides Circuit boards, PCB's though the grooves 20e to attach it with the chassis and to the back plane of the system. The side 20g is provided with slots 20i of similar dimension as that on 20d at regular intervals exactly coinciding with the openings 20f on 20b.

Figure 3 depicts a portion of the card guide frame 20 with the male fastener 12 mounted on the C-profile of the card guide in accordance with the embodiments of the present invention. The protrusion 10c on the left side of the male fastener is engaged with the slot 20i on the side 20g of the card guide and the protrusion 10c on the right side of the male fastener is placed on the slot 20d on the side 20a of the card guide. The engagements of the protrusions with the slots are made easy as the width of the slots 20d and 20i on all its sides are greater than the width of the protrusion 10c on all its sides. The engagement of the protrusions 10c with the slots ensures that the cylindrical threaded projection 11 extends outside the card guide slot 20f on side 20b. The riveted junction 10i is visible at the rear portion of the metal sheet 10b.

Figure 4 shows the assembling sequence of the male fastener 12 with the card guide frame 20 in accordance with the embodiments of the present invention. The protrusion 10c when mounted on the slot 20d on the card guide frame 20a is covered on three of its sides leaving one side open. A card guide plate 30 is attached to the open end of the protrusion. The card guide plate is a rectangular metal sheet with holes provided on its opposite ends along its breadth. The card guide plate 30 is mounted to the card guide frame such that its length 30a covers the open ended surface of the protrusion 10c mounted on the slot 20d of the card guide frame 20a. The card guide plate 30 is fastened to the card guide 20 through screw nut fastening mechanism 40 enabled through the holes provided on the card guide plate 30 and the flaps 20h. The arrangement arrests the male fastener 12.

Figure 5 shows an isometric front view of the male fastener mounted on the C-profile of the card guide embodying the principles of the invention. The cylindrical threaded projection 11 and its circumference 11a extends outside the card guide frame 20b through the openings 20f. The slot 20i on the side 20g of the card guide holds the right side protrusion 10c of the male fastener with its extreme sides 10h visible externally. The C-profile of the card guide encompassing the sides 20a, 20b, 20c and 20g can house as many male fasteners as required by the system. The illustrated card guide frame shows three such male fasteners.

The vertical height of the slots 20d and 20i on sides 20a and 20g respectively on the C-profile of the card guide is bigger in size to that of the rectangular protrusion 10c of the male fastener. The horizontal width of the slots 20d on side 20a and 20i on side 20g on the card guide is lesser than that of the length 10g of the male fastener's protrusion 10c. This arrangement provides for horizontal gaps for the protrusion 10c of the male fastener on its sides such that the male fastener has a limited, horizontal, movement within the slot 20d and 20i on the C-profile of the card guide. The vertical gaps thus provided between the slots 20d, 20i and the protrusion 10c of the male fastener enables the male fastener to have a limited rotational movement along its axis 11b. The horizontal gap due to the relative size difference between the horizontal slot width and the width of the protrusion 10c on all its other sides enables the male fastener to have a limited linear movement along the plane of its axis. The desired limited movement of the male fastener along its vertical, horizontal and angular plane can be accomplished by allowing a pre-determined gap between the slot 20d and slot 201 on the C-profile of the card guide 20 and the protrusion 10c of the male fastener 12, such that the edges of the surfaces 10f and10g of the protrusion 10c encounters the inner surface of the slots 20d and 20i when it rotates at an angle or tends to make any to and fro motion. Thus, further rotation or to and fro movement is prevented due to the resistance offered by the inner slot surface to the sides of the protrusion 10c.

These pre-determined horizontal and vertical gaps thus provided to the male fastener 12 on all its sides, engendered by relative size difference between the slots 20d and 20i and the protrusion 10c facilitates floating feature. The pre-determined gap in the preferred embodiment is at least 1 mm between the slot and the protrusion 10c of the male fastener on all of its sides so as to provide a floating male fastener with a tolerance of 1mm.

One aspect of the present invention was to remove the disadvantage of the existing prior art by providing at least a tolerance level of one mm between the nut axis and screw axis on a card guide whose width 20b is at least a minimum of 12 mm; where the prior art failed to maintain any tolerance for fastening the screw with the nut.

An advantageous feature of the above embodiments is that in case of card guide widths 20b getting reduced below 12 mm on technological advancements, still the tolerance level can be either maintained or increased beyond 1mm by reducing the size of obstruction 10 and the cylindrical threaded projection 11 of the male fastener corresponding to the decreased width of the card guide. Further, the width of 20b can be matched as close to the diameter of the cylindrical threaded projection 11 as allowed by the technology.

Further, in addition to the above illustrated male fastener which is one among the embodiments of the present invention, it is possible to have male fasteners of varying shapes and having additional components. Accordingly, figures 6 to 8 depict male fasteners with varying features in accordance with the embodiments of the present invention.

Figure 6a through 6b illustrates a male fastener 12 in accordance with one embodiment of the present invention. In this embodiment the male fastener 12 comprises an external obstruction 10. The obstruction 10 is in the shape of rectangular box having 10a as its sides along its length and 10b as its breadth. Two rectangular protrusions 10c are provided at the mid-point of the side 10b. A rectangular sheet 10d is attached perpendicular to the top side 10a, mid-point along its length. This external obstruction 10 is mounted to the male fastener's head 11c by placing the rectangular sheet 10d on the surface 11d of the male fastener such that the mid-point of the rectangular sheet 10d coincides with the line of the axis 11b of the male fastener. In this embodiment the head of the male fastener 11c is semicircular with its flat side 11e facing the surface 10e of the rectangular sheet. The rectangular sheet 10d can be firmly secured to sheet 10. The above physical feature prevents the male fastener from sliding out in the direction of 10d along the surface 10e of the obstruction 10, as few applications may demand easy removal of the male fastener by not securing the portion 11e of the male fastener with 10e of the obstruction 10. The obstruction 10 having protrusions 10c on either side along its breadth is mounted on slot 20d and 20i on the C-profile of the card guide such that the protrusion 10c on the left side of the obstruction 10 is engaged with the slot 20i on the side 20g of the card guide and the protrusion 10c on the right side of the obstruction 10 is placed on the slot 20d on the side 20a of the card guide. The engagements of the protrusions with the slots are made easy as the width of the slots 20d and 20i on all its sides are greater than the width of the protrusion 10c on all its sides. The engagement of the protrusions 10c with the slots ensures that the cylindrical threaded projection 11 extends outside the card guide frame 20b through the opening 20f.

Figure 6c illustrates a male fastener in accordance with one embodiment of the present invention. The male fastener illustrated in the above figure, comprises of an external obstruction 10 secured firmly with the head 11c of the male fastener. In this embodiment, the rectangular sheet 10d is dispensed with as the side 11e (not shown in fig) of the male fastener's head is firmly attached with the side 10e (not shown in fig) of the obstruction either by riveting it or by fastening it with a screw and nut mechanism. The obstruction 10 having protrusions 10c on either side along its breadth is mounted on slot 20d and 20i on the C-profile of the card guide such that the protrusion 10c on the left side of the obstruction 10 is engaged with the slot 20i on the side 20g of the card guide and the protrusion 10c on the right side of the obstruction 10 is placed on the slot 20d on the side 20a of the card guide. The engagements of the protrusions with the slots are made easy as the width of the slots 20d and 20i on all its sides are greater than the width of the protrusion 10c on all its sides. The engagement of the protrusions 10c with the slots ensures that the cylindrical threaded projection 11 extends outside the card guide frame 20b through the opening 20f. This particular embodiment of the invention can be used in applications which require a custom designed male fastener where removal of the male fastener from the obstruction is not frequented.

Figure 7 shows a male fastener 12 with its head portion 11c enclosed within a rectangular box frame 10. The head of the male fastener 11c (shown in dotted lines as it is hidden behind 10a) is the flange portion of the cylindrical threaded projection 11. The cylindrical threaded projection 11 of the male fastener extends outside the rectangular box frame 10 through its opening 10a. The flange portion 11c arrests the male fastener and prevents its ejaculation through the opening 10a of the rectangular box frame. One end of the flange portion 11c is provided with a small protrusion 11e. The rectangular box frame 10 comprising of its sides 10b along its breadth and 10d along its length has a small upright protrusion 10e at its bottom length 10b projecting inside the box frame. This protrusion 10e acts as an obstruction to the protrusion 11e of the head of the male fastener 11c so as to prevent a 360 degree rotation of the male fastener along its axis 11b. Protrusions 10c provided at either side, along the length 10d of the rectangular frame, acts as an external obstruction to the male fastener. (One of the protrusions is hidden by the cylindrical threaded projection 11) The protrusion 10c on the left side of the rectangular enclosure is engaged with the slot 20i on the side 20g of the card guide and the protrusion 10c on the right side of the rectangular enclosure 10 is placed on the slot 20d on the side 20a of the card guide. The engagements of the protrusions with the slots are made easy as the width of the slots 20d and 20i on all its sides are greater than the width of the protrusion 10c on all its sides. The engagement of the protrusions 10c with the slots ensures that the entire cylindrical threaded portion 11 of the male fastener extends outside the card guide frame 20b through the opening 20f.

FIG 8 shows the cross-sectional top view of the male fastener described above. The protrusion 11e on the head of the male fastener 11c acts as an obstruction integral and external to the male fastener and the projection 10e on the rectangular box enclosure 10 acts as an obstruction on the enclosure. The opening 10a (shown as dotted lines) on the rectangular box enclosure is covered by the flange 11c of the male fastener's head. The male fastener in this embodiment is made to perform maximum rotational movement within the range of above 270 degree to slightly less than 360 degree to suit its varied applications. The projection 10e on the rectangular enclosure obstructs the male fastener from making a complete rotation.

The above features discussed above merely illustrate the principles of the invention. The male fasteners discussed above can be modified to be used as a thread less fasteners wherein the female part to be coupled could be either threaded or thread less such that a magnetic force of attraction between the male and female parts fastens the component parts.

The inventor envisages the possibility of having obstruction integral with and external to the male fasteners in the shape of square, rectangle, octagonal, hexagonal, pentagonal, triangular etc., In such sizes and shapes, the slot 20d and 20i as shown in figure 2 can be designed to provide the necessary width, matching the dimensions of the obstruction so as to provide the male fastener with limited floating movement along its horizontal, vertical and angular plane by allowing pre-determined horizontal and vertical gaps.

A method of the above self-aligning nut pursuant to the principles of the invention can be made from any desired material. Indeed, it can be made of steel, mild steel, die-cast materials, plastic, fibre, moulded material depending upon its applications.

Advantages:

1. The existing prior art did not provide for any tolerance for coinciding of screw axis with the nut axis enabling to fasten the screw with the nut on the card guide having a width less than 13mm. One embodiment of the present invention provided a tolerance level of at least 1 mm each on either of two card guides thereby allowing a smooth attachment of the face plate with the card cage. Further this reduced the stress upon the fastening mechanism on repeated jack-in and jack-out of the Printed Circuit Board.

2. Another solution to address the above issue was to have a standard floating nut. But the standard floating nuts require a minimum card guide width of 17.6 mm. One embodiment of the present invention provided a male fastener instead of a floating nut that would fit into C-profile of the card guide of the size 12.0 mm or less within the confined space thereby dispensing with the requirement of standard floating nut.

3. The embodiments of the above invention can be applied to any card guides with varying sizes where space constraints are involved.

4. The embodiments of the above invention can be also used in any floating screw mechanisms where space constraints are involved.

5. The embodiments of the above invention made it possible to provide floating male fasteners in the card guide with limited modification of the form fit or function of the card guide.

It will thus be appreciated that those skilled in the art will be able to device numerous alternative arrangements that, while now shown or described herein, embody the principles of the invention and thus are within its spirit and scope.

We Claim:

1. The method for a male fastener by

Providing at least one or more obstructions for the male fastener in such a way that 360 degree rotational movement of the male fastener is prevented;

and

Limiting the Linear movement of the male fastener along the plane of its axis.

2. The method of claim 1, wherein obstruction is provided at least as an integral entity, external entity and a combination thereof.

3. The method of claim 2, wherein obstruction is at least one of plurality of shapes including a rectangle, square, triangle, octagonal, hexagonal, circular, semi-circular, conical, pentagonal etc.,

4. The method of claim 1 wherein male fastener enables the nut hole to have access to the axis of the male fastener during its coupling

5. The method of claim 1 wherein male fastener includes a standoff threaded externally, a bolt, off-the-shelf screw, caged screw, recess screw; thread less screw which can be coupled with thread less nut through magnetic force.

6. The method of claim 1 wherein the male fastener is made of a die-cast material, plastic, fibre, moulded materials, metal etc.,

7. The method of claim 1 wherein obstruction for the male fastener is made from die-cast material, plastic, fibre, moulded materials, metal, etc.

9. The male fastener comprising of

At least one or more obstructions, either externally or integrally, for the male fastener in such a way that 360 degree rotational movement of the male fastener is prevented and linear movement of the male fastener along the plane of its axis is limited.

10. The male fastener substantially described with reference to the accompanying drawings.