US3191670A

US3191670A - Finned heat exchangers

Info

Publication number: US3191670A
Application number: US126263A
Authority: US
Inventors: William C Jones
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1961-07-24
Filing date: 1961-07-24
Publication date: 1965-06-29
Anticipated expiration: 1982-06-29

Description

June 29, 1965 w. c. JONES 3,191,670

FINNED mm EXC NGERS United States Patent 3,191,670 FTNNED TEAT EXCHANGERS William 6. Tones, Medford, Mass, assignor to Westinghouse Electric Corporation, East iittsburgh, Pa., a corporation of Pennsylvania Filed 11113 24, 1961, Ser. No. 126,263 1 Claim. (Cl. 16576) This invention relates to heat exchangers having finned tubes in metal casings.

Many heat exchangers used for the cooling and heating of air, consist of spaced-apart, hollow tubes having closely spaced, plate-type fins common to all tubes, supported in protective casings having air inlets and outlets, and having headers at the ends of the tubes. In prior heat exchangers of this type, the casings have had sheet metal, top and bottom walls in contact with the tops and bottoms respectively, of the fins, and the finned tube cores have been held in the casings by structural angles attached to the top and bottom walls, and contacting opposite edges of the fins.

This invention forms internally bulging ribs in the iongitudinal centers of the top and bottom walls of a casing, and forms complemental-shaped notches in the centers of the tops and bottoms of the fins, with the ribs fitting snugly in the noches. Advantages of this construction are that the ribs stifien the sheet metal top and bottom of a casing; the ribs in the notches in the fins locate and hold the core in the casing, and the ribs in the notches prevent air from by-passing the core by flowing between the top and bottom walls and the core.

An object of this invention is to stiffen the sheet metal top and bottom walls of a casing of a heat exchanger by forming ribs in the longitudinal centers of the walls.

Another object of this invention is to use ribs in the longitudinal centers of the top and bottom walls of the casing of a heat exchanger having plate-type fins, and notches in the centers of the tops and bottoms respectively, of the fins for locating and holding the finned tube core within the casing.

Another object of this invention is to use ribs in the top and bottom walls of a casing of a heat exchanger having plate-type fins, and notches in the centers of the tops and bottoms respectively, of the fins for preventing the bypassing of air around such ends.

This invention will now be described with reference to the annexed drawings, of which:

FIG. 1 is a perspective view of a heat exchanger embodying this invention;

FIG. 2 is a section along the lines 22 of FIG. 1, and

FIG. 2 is a section similar to FIG. 2, but showing a Wider heat exchanger having difierently shaped ribs and notches.

Referring first to FIGS. 1 and 2, a row of vertically aligned, parallel, spaced-apart, hollow tubes 10, has ve1ti cally-extending, closely-spaced, plate-type fins 11 of sheet metal around and in contact with all of the tubes 10. The tops and bottoms of the fins 11 have semi-circular notches formed in the centers, and in which are fitted semi-circular ribs 12 and 13 respectively, in the longitudinal centers of the sheet metal top wall 15, and bottom wall 16 respectively, of casing 17 The top wall 15 has end portions 18 which extend normal thereto, and has inturned portions 19 at the upper ends of the portions 18, which extend parallel to the Wall 15. The bottom Wall 16 has end portions 20 which extend normal thereto, and has inturned portions 21 at the lower ends of the portions 20, which extend parallel to the wall 16. The wall portions 18 and 20 have perforations 22 and'23 respectively, for receiving rivets or bolts for securing a duct to the casing 17.

3,191 ,670 Patented June 29, 1965 'ice A flanged end plate 25 has outwardly-turned portions 27 which extend across and are attached to the ends of the wall portions 19 and 21, and has outwardly-turned portions 23 which extend across and are attached to the ends of the wall portions 18 and 20, at one end of the casing 17. A similar, flanged end plate 30 has outwardlyturned portions 31 which extend across and are attached to the ends of the wall portions 19 and 21, and has outwardly-turned portions 32 which extend across and are attached to the ends of the wall portions 18 and 20 at the other end of the casing 17 A tie rod 40 extends through the walls 15 and 16 midway between the end plates 25 and 30 and to one side of the fins 11, and has threaded ends with nuts 41 thereon above and below the walls 15 and 16. A similar tie rod 42 extends through the walls 15 and 16 opposite the tie rod 40 on the other side of the fins 11, and has threaded ends with nuts 43 thereon above and below the walls 15 and 16. The nuts 41 and 43 are adjustable on the tie rods 40 and 42 respectively, for moving the walls 15 and 16 towards each other until the ribs 12 and 13 fit snugly into the notches provided therefor in the tops and bottoms respectively, of the fins 11.

The end fins 11 are spaced from the end plates 25 and 30 for providing spaces for headers which are not shown. A typical tube connection 50 to one header is shown on FIG. 1.

FIG. 3 of the drawings shows another embodiment of this invention in which the heat exchanger core has three vertical rows of tubes 10A, and in which the fins 11A are wider than the fins 11 of FIG. 2 for contacting the additional tubes. Also, the fins 11A of FIG. 3 have triangular notches in their tops and bottoms in which are fitted triangular ribs 12A and 13A respectively, in the longitudinal centers of the top and bottom walls 15A and 16A respectively. The remainder of the structure of FIG. 3 is similar except as to size, as corresponding structure of FIG. 2, and so has been given the same reference characters.

The ribs in the top and bottom plates by being drawn tightly into the notches in the tops and bottoms of the fins, locates the finned core and holds it against displacement. By-passing of the air being conditioned around the tops and bottoms of the fins is also prevented. The ribs also stifien the sheet metal top and bottom plates.

What is claimed is:

A heat exchanger comprising a plurality of spacedapart, hollow tubes having parallel axes, a plurality of spaced-apart, parallel, plate-type fins around and in contact with said tubes, said fins having notches in the centers of their ends, casing walls of sheet metal in contact with said ends of said fins and having ribs in their centers shaped complemental to the shape of said notches in said notches, and tie rods extending through said walls on opposite sides of said fins, the ends of said rods being threaded, and nuts on said threaded ends on opposite sides of said Walls.

References Cited by the Examiner UNITED STATES PATENTS 123,602 2/72 Wiegard 130 1,208,790 12/16 Junkers 16585 2,267,905 12/41 Frantz 165-122 2,599,965 6/52 Young 165-434- CHARLES SUKALO, Primary Examiner.

HERBERT L. MARTIN, ROBERT A. OLEARY,

Examiners.