US2062470A

US2062470A - Cooling tube for dynamo-electric machines

Info

Publication number: US2062470A
Application number: US717696A
Authority: US
Inventors: Mossay Paul Alphonse Hubert
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-04-03
Filing date: 1934-03-28
Publication date: 1936-12-01
Anticipated expiration: 1953-12-01

Description

Dec. l; 1936. l P. A; H. MossAY COOLING TUBE FOR DYNAMO-ELECTRIC MACHINES Filed March 28, 1934 5 Sheets-Sheet l Dec. l, 1936. P. A. H. MossAY COOLING TUB FOR DYNAMO-ELECTRIC MACHINES 5 Sheets-Sheet 2 .[/w/./vra/Q I 73M No# Filed March 28, 1934 Dec. 1,1936. p A, MOS'SAY l 2,062,470

COOLING TUBE FOR DYNAM0-ELECTR1C MACHINES 3 Sheets-Sheet` 3 Filed March 28, 1934 Patented Dec. l, 1936 UNITED STATES PATENT GFFICE Paul Alphonse Hubert Mossay, Norwich, England Application March 28,

1934, Serial No. 717,696

lin Great Britain April 3, 1933 1d) Claims.

The invention relates to cooling tubes through which the internal air of an enclosed electric dynamo machine is circulated and cooled by colder air blown over the outsides of the tubes, and particularly to those tubes which are made of sheet metal and shaped to an approximately rectangular cross-section, the ends of the tube being provided with bends for insertion into sheet metal cylinders or segments enclosing the machine near each end thereof.

The objects of the invention are to effect economy in manufacture while ensuring efcient jointing of the parts of the tubes, and between the tubes and the cylindrical parts or segments in which their ends are inserted so as to minimize leakage of dust laden air into the tubes or into the machine, and to increase further the strength and rigidity of the tubes and also to increase the cooling surface.

A cooling tube according to the invention is composed of two similar dished parts stamped or presse-d out of sheet metal, preferably having a straight portion and two end bends, and provided with perimetral anges, the two parts being placed together with the flanges in corresponding relation with intermediate strips or plates between the anges. When the tubes are made of steel, the parts are prefer-ably welded together, for example, by spot or seam welding, but if made of other metal, they may be soldered or brazed or hot galvanized.

The intermediate plate increases the thickness of the combined flanges, so that the slotted cylindrical casing parts or segments, in which the end bends of the tubes are inserted, can be efficiently punched with slots to receive the Bauges.

The intermediate plate increases the internal cooling surface and in order further to increase the cooling surface, the plate may extend beyond the anges of the dished parts of the tubes and, if desired, beyond the ends of the tubes and, therefore, beyond the end shields of the machine, so as to act as cooling ins as well as a diffuser that ensures an even distribution of the cooling air between the tubes.

The dished parts oi the tubes provided with end bends are preferably tapered, so that when the end bends are forced into the slots in the cylindrical casing segments or other parts of the machine by a wedging action, a tight iit is ensured.

In the drawings:

Figure 1 is a side view of a cooling tube, partly broken away at one end to show the intermediate plate, and

Figure 2 is an inverted plan of the tube.

Figure 3 is a cross-section on the line III-III of Figure 1.

Figure 4 is a similar cross-sectional view of another form of tube.

Figures 5 and 6 are, respectively, a plan and side view of a portion of a cooling tube xed in a portion of a slotted cylindrical casing seg ment.

Figure '7 is a side view of a portion of a still further form of tube.

Figure 8 is a side sectional elevation of part of an enclosed dynamo electric machine, showing one cooling tube in position.

Figure 9 is an end sectional elevation of part of the machine shown in Figure 8, the section being taken on the line IX-IX, Figure 8.

ln the examples illustrated, each tube comprises two dished parts l and 2 stamped or pressed from sheet steel, each of these parts having a straight channel 3, end channels or bends Ll and 5, and a flat perimetral flange 6, except at the edges l which are to surround the open ends of the tube.

The two parts i and 2 may be placed together, with their flanges in corresponding relation and with an intermediate flat steel strip or plate 8 conforming in shape to the flanges 6 inserted between them, as indicated in Figures 1, 2 and 3. The plate 8 near the open ends of the tube may have arcuate or other shaped edges 9 to permit free inlet to the air and provide room for using a simple expanding tool to open the tube orifice when inserted in the segment l2. A composite tube so compiled is clamped and the flanges and plate are secured together by Soldering or brazing, but preferably by spot welding, as indicated for example at the spots I0.

The plate divides the tube into separate passages. If desired, more than one plate 8 may be interposed, as indicated in Figure 4, some of the plates being dished, so as to sub-divide the tube into a number of passages, the air to be cooled being thus split into comparatively thin strata between walls of good heat conducting material, thereby considerably increasing the cooling eiect.

The dished parts i and 2 of the tube are so shaped that their end bends are tapered so as to ensure a tight fit when the bends are forced into correspondingly shaped holes i I in the cylindrical parts or segments l2 which form parts of the enclosing casing of the dynamo electric machine. The flanges 6 and the plate 8 are trimmed or tapered, as indicated at 20, for the same purpose.

The bends are preferably welded to the segments I2, as indicated at I3, Figure 6, to ensure a further wedging action by the contraction of the Weld.

The plates 8 in conjunction with the flanges 6 form relatively thick composite flanges, so that the slots I4 in the segments I2 which receive them, can be of such width that they can be efficiently punched.

The tubes so constructed are not only eflicient from the cooling point of view and can be adequately sealed at their flanges, so as to exclude dust laden air, but they are strong and rigid.

Figures 8 and 9 illustrate part of an enclosed dynamo-electric machine provided with cooling tubes I'I of the form shown in Figures 1, 2 and 3. 'Ihe machine, as usual, has end shields I8 and I9 and sheet metal casing segments I2 comprising a casing, an external fan 2I for blowing air over the outsides of the cooling tubes I'I and an internal fan 22 for circulating the internal air through the interior of the cooling tubes. As usual, these fans are arranged to direct the flow of air in opposite directions, as indicated by the arrows 23 and 24, which respectively indicate the direction of flow of the cooling air and the internal air,

In order to increase further the cooling surface, the intermediate plate 8 may extend beyond the flanges 6 along the whole length and, if desired, also beyond the bends at the ends of the tubes, as shown in Figure 7.

I claim:

1. In combination with a dynamo electric machine comprising a casing; a cooling tube comprising two sheet metal parts each being dished and having a straight portion, two bends and a perimetral flange, an intermediate sheet metal plate, said parts being placed together with their flanges in corresponding relation and with said plate between and in contact with said flanges, said flanges and plate being welded or otherwise suitably secured together.

2. The combination with a dynamo electric machine a cooling tube as specified in claim 1, wherein an intermediate plate, which is adjacent to the open ends of the tube,\is provided with a cut away to facilitate the insertion of an expanding tool.

3. The combination with a dynamo electric machine a cooling tube as specified in claim 1, having tapered bends substantially as and for the purpose hereinbefore set forth.

4. The combination with a dynamo electric machine a cooling tube as specified in claim 1, having an intermediate plate which extends beyond the flanges of the dished parts of the tube, substantially as and for the purposes hereinbefore set forth.

5. In an enclosed dynamo electric machine having slotted cylindrical casing segments for the reception of cooling tubes, a plurality of cooling tubes each comprising two stamped sheet metal parts having straight portions, bends at the ends and perimetral flanges, and an intermediate metal plate, said parts being placed together with their flanges in corresponding relation and with the intermediate plate between and in contact with said flanges, said flanges and plate being welded together, and the bends of said tubes being inserted in the slots of said casing segments and being welded to said segments substantially as and for the purpose hereinbefore set forth.

6. In an enclosed dynamo electric machine having a casing provided with openings for the reception of cooling tubes, a plurality of cooling tubes mounted on said casing and each comprising two sheet metal parts having straight portions, bends at the ends and perimetral flanges, and an intermediate metal plate, said parts being placed together with their flanges in corresponding relation and with the intermediate plate between and in contact with said flanges, said flanges and plate being fixed together, and the bends of said tubes being inserted in the openings in said casing and suitably secured thereto.

7. In an enclosed dynamo electric machine having a casing, a plurality of cooling tube devices mounted on and exterior of the casing and communicating with the interior thereof, each of said devices comprising two outer dished metallic plates having flanged parallel edge portions and two inner dished metallic plates having flanged parallel edge portions, the flanges of the exterior and interior plates being secured together so as to provide an interior fluid passageway and two exterior fluid passageways surrounding and enclosing the interior passageway, whereby the air passing through all the passageways is split up and thoroughly exposed to the surfaces of the device to increase the cooling effect.

8. In an enclosed dynamo electric machine having a casing, a plurality of cooling tube devices mounted on and exterior of the casing, each of said devices comprising two outer dished metallic plates having flanged parallel edge portions and two inner dished metallic plates having flanged parallel edge portions, the flanges of the exterior and interior plates being secured together so as to provide an interior fluid passageway and two exterior fluid passageways surrounding and enclosing the interior passageway, whereby the air passing through all the passageways is split up and thoroughly exposed to the surfaces of the device to increase the cooling effect.

9. In an enclosed dynamo electric machine having a casing, a plurality of metallic cooling tube devices mounted on and exterior of the casing, each device comprising an interior fluid passageway and enclosing uid passageways surrounding the interior fluid passageways, whereby each cooling tube device is subdivided into a plurality of passageways certain of the heat-conducting walls whereof are exposed at both sides to the air flow to increase the cooling effect.

10. In an enclosed dynamo electric machine having a casing, a plurality of metallic cooling tube devices mounted on and exterior of the casing, each device comprising an interior fluid passageway and having end portions terminating exterior of the casing and fluid passageways enclosing the interior fluid passageway, all of said passageways communicating with the interior of the casing, said end portions increasing the area of the cooling surfaces of the device.

PAUL ALPHONSE HUBERT MOSSAY.