Title of Invention

AN ACOUSTICALLY INSULATING ENCLOSURE FOR ELECTRICAL AND MECHANICAL ROTATING MACHINES

Abstract

The invention relates to an acoustically insulting enclosure for electrical mechanical rotating machines in particular an engine or generator comprising:- -a side cover assembly (1) constituting of two symmetrical sub-assembles (3) bolted together at a joint face (4), said symmetrical subassemblies (3) each having a plurality of end walls (5), and a side wall (6); -a top cover assembly (2) constituting of a plurality of symmetrical end walls (29), a plurality of side walls (30) facing each other, and a top wall (31), said top cover assembly (2) being releasably connected to said side cover assembly (1) by a plurality of clamps, a gasket material being held in compression in a plurality of mating surface (34,24,25), -characterized in that said side wails (5,6,29,30) of said side and top assemblies (1,2) being configured double walls, outer sheet of each wails being a straight single piece, inner sheet of each wails comprising a series of pieces (11,12,18,19,20,38,39) each being disposed at a predetermined distance (x) from said outer sheet at a predetermined angle () below 5° and in that a plurality of ribs (13,14,16,17,21,25) being provided perpendicularly on an inner surface of said outer sheet, each adjacent ribs of said plurality of ribs having variable height such that said inner sheet welded on said ribs achieve a taper configuration forming said predetermined angle with respect to said outer sheet. {Figs-l,3,4,4a&7}

Full Text

Fleld of Invention: The invention relates to 94 insulating enclosure. electrical and mechanical rotating machines. Background of the Invention. Electrical synchronous generator, CACW (Closed Air circuit water cooled) and the like electrical rotating machines produce noise of the order of I04dBA It is necessary to reduce this high level of noise to audible level. Therefore, the main object of the present invention is to propose a simple and inexpensive enclosure which effectively reduces noise produced by rotating machines while in operation. Another object of the present invention is to propose a double wall type enclosure which reduces the noise to a deBired level without any increase in space-requirement Yet another object of the present invention is to propose a double wall type with taper configuration enclosure which effectively arrest the sound waves. A further object of the present invention is to propose an enclosure to acoustically insulate sound waves of all frequencies including frequencies ranging from 31 Hz to 8KHz generated by a rotating electric or mechanical machine. Summary of the invention: According to the present invention, there is provided an acoustically insulating enclosure for electrical mechanical rotating machines in particular an engine or generator comprising a side cover assembly constituting of two symmetrical sub-assembles bolted together at a joint face, said symmetrical subassemblies each having a plurality of end walls, and a side wall; a top cover assembly constituting of a plurality of symmetrical end wallB, a plurality of side walls facing each other, and a top wall, said top cover assembly being releasably connected to said side cover assembly by a plurality of clamps, a gasket material being held in compression in a plurality of mating surface, characterized in that said side walls of said side and top assemblies being configured double walls, outer sheet of each walls being a straight single piece, inner sheet of each walls comprising a series of pieces each being disposed at a predetermined distance from Baid outer Baid outer Bheet at a predetermined angle (a) below 5° and in mat a plurality of ribs being provided perpendicularly on an inner surface of said out sheet, adjacent ribs of said plurality of ribs having variable height such mat said inner sheet welded on said ribs achieve a taper configuration forming Baid predetermined angle with respect to Baid outer sheet The nature of the invention, its objectives and further advantages residing in the same will be apparent from the following description made with reference to non-limiting exemplary embodiments of the invention represented in the accompanying drawings. Brief description of the Accompanying drawings. Fig 1. Conventional and new enclosure looking from outside. Fig 2. Isometric view of new enclosure Fig. 3 Wire Frame model of side cover assembly Fig. 4. Cross section view taken along line A-A of Fig. 3. Fig. 4a. Detailed 'Y' of Fig. 4 Fig. 5. Wire Frame model of Top cover assembly Fig. 6. Cross section view taken along line B-B of Fig. 5. Fig. 7. Cross section view taken along C-C. Description of the preferred embodiment. Fig. 1 refers to both conventional and new enclosure. From out side both the enclosures will look alike. New enclosure is different from the conventional due to the structure of enclosure walls. Conventional enclosure has number of single iron sheet walls of thickness 5, 8 or 10mm, welded at edges to give the required shape of side cover and top cover assembly. New enclosure also has similar shape and size of walls as of conventional enclosure, but each wall is specially configured double wall. Outer wall is iron sheet of 5, 8 or 10 mm thickness in a single piece having number of perpendicular ribs welded on the inner surface. Height of adjacent ribs is different so that the inner iron sheet of 3.15, 4 or 5 mm welded on the ribs form a predetermined angle with respect to outer sheet. Referring to Fig. 2, which is the isometric view of new enclosure, enclosure comprises two assemblies- side cover assembly 1 and top cover assembly 2. Top cover assembly 2 is placed on side cover assembly 1 with gasket glued on the mating surfaces 34, 24 and 25 and secured by clamps to form the complete enclosure as shown in Fig. 1. Fig. 3 refers side cover assembly 1 which is made of two symmetrical assemblies 3, bolted together at joint face8. Symmetrical assemblies 3 are made of two similar end walls 5, a side wall 6, a top side wall 7 and a bottom side wall 8. Top side wall 7 and bottom side wall 8 have rectangular opening 9 for accommodating cooler tube bundle. Fig. 4 refers to the cross section view taken along line A-A of Fig. 3. Side wall 6 is made of outer single piece wall 10 of thickness 5, 8 or 10 mm. Inner wall of 3.15, 4 or 5mm thickness, is a series of pieces 11 and 12 welded on the edges of ribs 13 and 14. Height of the ribs 13 and 14, and the distance between them are so chosen that the inner wall pieces forms an angle (a) of about 5° with the outer wall and has a distance x mm (refer fig 4a). Depending on the length of side wall 6, number of these taper configurations will vary keeping the angle a and the distance x same. End walls 5 also has similar taper configurations as shown in fig 4, having single piece outer wall 15 and inner wall pieces 18,19 and 20 welded on the ribs 16, 17, 21, 22, 23 , 24 and 25 (Refer Fig. 3). End wall has rectangular openings 26 for approaching the foundation bolts of the machine. This opening is covered with a suitable double wall cover. End wall also has a flange 27 welded on outer wall having holes to take bolts for assembly of two symmetrical assemblies 3. Angle 28 welded on the end wall forms the surface on which complete enclosure gets supported on the machine base frame. Fig. 5 refers to the wire frame model of the top cover assembly 2. Top cover assembly is made of two symmetrical end walls 29 and side walls 30 facing each other and a top wall 31. Fig. 6 refers to the cross section view taken along section line B-B of fig. 5. Top wall 31 and end walls 29 have similar taper wall configurations as that of side wall 6, having straight outer wall and taper inner walls. Side wall 30 has two straight parallel sheets 32 separated by a distance of 50 mm. Bottom of the side wall 30 is formed by the horizontal flange 33. Bottom surface of the flange 33 rests on the top side cover 7 at location 34 and bottom surface of angles 36 and 37 rests on the ribs 24 and 25 respectively of side cover (fig. 3) when the top cover 2 is placed on the side cover 1. Semicircular opening in top cover 2 matches with the symmetrical opening in side cover 1 to form the complete circular opening 42 for rotor shaft to pass through on both drive and non-drive end side. Fig. 7 is the cross sectional view taken along section line C-C. Outer wall 35 of the end wall (29) is a single piece wall bent at edges, so that when top cover assembly 2 rests on the side cover assembly 1, the bent portion will overlap on the end walls of the side cover 1. Inner taper sheets 38 and 39 welded on the edges of ribs 40 and 41 and angles 36 and 37. The invention described hereinabove is in relation to a non-limited embodiment of the invention. The other features will also fall within the accompanying claims. WE CLAIM: l. An acoustically insulting enclosure for electrical mechanical rotating machines in particular an engine or generator comprising;- -a side cover assembly (1) constituting of two symmetrical sub-assembles (3) bolted together at a joint face (4), said symmetrical subassemblies (3) each having a plurality of end walls (5), and a side wall (6); -a top cover assembly (2) constituting of a plurality of symmetrical end wails (29), a plurality of side walls (30) facing each other, and a top wall (31), said top cover assembly (2) being releasably connected to said side cover assembly (i) by a plurality of clamps, a gasket material being held in compression in a plurality of mating surface (34,24,25), -characterized in that said side walls (5,6,29,30) of said side and top assemblies (1,2) being configured double walls, outer sheet of each walls being a straight single piece, inner sheet of each wails comprising a series of pieces (11,12,18,19,20,38,39) each being disposed at a predetermined distance (x) from said outer sheet at a predetermined angle () below 5° and in that a plurality of ribs (13,14,16,17,21,25) being provided perpendicularly on an inner surface of said outer sheet, each adjacent ribs of said plurality of ribs having variable height such that said inner sheet welded on said ribs achieve a taper configuration forming said predetermined angle with respect to said outer sheet. 2.The enclosure as claimed in claim 1, wherein said symmetrical subassemblies (3). a top side wall (?) and a bottom side wall (8) each having an opening (9) for accommodating cooler tube of said machines, 3.The enclosure as claimed in claim 1, wherein said end wails (5) has an plurality of bolts for assembly of said symmetrical subassemblies (3), an angle piece (28) being provided on the end walls (5) forming a surface on which said enclosure supported on a base frame of said machine. 4. The enclosure as claimed in claim 1, wherein a bottom surface of said side walls (30) is formed by a flange (33) resting on said top side cover (7) at a location (34), said walls (30) having formed with two parallel vertical sheets (32) being maintained separated by a distance of 50 mm. 5. The enclosure as claimed in claim 1, wherein said side cover assembly (1) and said top cover assembly (2) each comprises of metal sheet of mild steel or any metal sheet selected for constructing the structure of the enclosure. 6. The enclosure as claimed in claim 4, wherein said end walls (29) has outer wall (35) bent at edges for over lapping on said end walls (5) when said top cover assembly (2) rests on said side cover assembly (1). 7. The enclosure as claimed in claim 3, wherein said inner sheet (38, 39) of said end walls (29) is welded on a edge of a ribs (40, 41) and on an angle pieces (36, 37). 8. The enclosure as claimed in claim 1, wherein a thickness of said outer sheet is selected dependent on the frequency of noise to be suppressed, preferably above 5 mm. 9. The enclosure as claimed in claim 1, wherein said predetermined distance (x) between said outer sheet and said inner sheet is selected at a value preferably of 50 mm. 10. An acoustically insulating enclosure for electrical and rotating machines in particular an engine or generator as herein described and illustrated.

Documents:

843-del-2003-abstract.pdf

843-del-2003-claims.pdf

843-del-2003-complete specification (granded).pdf

843-del-2003-correspondence-others.pdf

843-del-2003-correspondence-po.pdf

843-del-2003-description (complete).pdf

843-del-2003-drawings.pdf

843-del-2003-form-1.pdf

843-del-2003-form-19.pdf

843-del-2003-form-2.pdf

843-del-2003-form-3.pdf

843-del-2003-gpa.pdf

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