US2456492A

US2456492A - Convector heating unit

Info

Publication number: US2456492A
Application number: US578091A
Authority: US
Inventors: Arthur G Dixon
Original assignee: Modine Manufacturing Co
Current assignee: Modine Manufacturing Co
Priority date: 1945-02-15
Filing date: 1945-02-15
Publication date: 1948-12-14
Anticipated expiration: 1965-12-14

Description

A. G. @man .2,456,492

CONVECTOR HEATING UNIT Fl@ Fb. l5, 1945 Patented Dec. 14, 1948 Arthur G. Dixon, Racine, Wis., assigner to Medine ManufacturingCompany, Racine, Wis., a corporation of Wisconsin Application February 15, 1945, Serial N0. 578,091

6 Claims. (Cl. 257-4136) This invention relates to 'a convector heating unit and its principal object is to increase the eiilciency of heating devices of this character. A convector heating unit is commonly installed in an enclosure or stack arranged to admit air from the room through an opening in the lower end of the enclosure and to emit the heated air through a grilled opening at the upper end of the enclosure. 'I'he lower opening may be grilled or not grilled, as desired. The air in the enclosure is warmed by the heating unit and, thereby is made lighter thanthe room air outside the enclosure and consequently rises in the enclosure and is discharged into the room through the upper opening of the enclosure.

For architectural reasons convector enclosures are usually installed either in or against a wall of a, room. Air enters the enclosure only through the opening at the bottom of the front wall thereof but occasionally the ends of the enclosure may be open to supplement the volume of air entering the heating unit through the lower front opening.-

In consequence of these limitations, the present day convector heatingv unit, which is usually rectangular in cross section, does not make wholly eflicient use for heat transfer purposes of .the metal which it contains. The air entering the lower front opening of the enclosure is caused by natural momentum to flow unevenly through the heating unit, tending to pass to a greater degree through the portion of the heating unit farthest removed from the air entrance opening. Thus the forward portion of the ordinary heating unit is relatively ineective. M

Another object of the invention is the provision of a convector heating unit formed of headers, tubes and ns, of which the ns are of inverted V shape or the major. portion of the iin surface Fig. 2 is a, vertical cross section taken on the -line 2-2 of Fig. 1;

Fig. 3 isa vertical cross section partly broken away and showingl a slightly modifiedl form of a convector heating unit; and

Fig. 4 is a similar section illustrating a second modification.

Referring to said drawings and first to Figs. 1 and 2., the reference character v5 designates a cabinet or other enclosure having a lower air inlet opening 6 in its front wall 'l and a warm air discharge opening 8 at the upper end of said front wall. The upper opening is provided with a grill 9 and the lower opening may or may not be provided with a grill.l l

Supported upon the side walls |10 of the cabinet,

as by hangers I l' and brackets I2,.is a convector heating unit I3 embodying a simpleform of the present invention and disposed entirely above the.

air inlet opening.,v The unit comprises headers I4 which are connected by tubes l5 alongwhich v are strung a multiplicity of fins I6 suitably bonded to the tubes. In this present'form the unit is' I shown as connected to a two-pipe steam or hot water system, but it may. be used in a one-pipe y system if so desired. The reference characters I1, I8 designate the supply and discharge respectively.

In order to obtain the most efficient heat transfer without the use of relativelyl wide fins, the latter arepreferably constructed of inverted V formation with one ofthe tubes I5 disposed at the apex portion of the iins and the other tubes that the width of the fin is reduced, consequently' disposed adjacent the ends thereof. The fins i1- lustrated in Figs. 1 and2 are of symmetrical design together with a symmetrical distribution of f the tubes in the cross section or depth of the unit.

An inverted V formation of fin has theadvantage reducing resistance to airflow through the unit; yet a total of extended surface area, is maintained, thereby sustaining the totalof heat transfer capacity asy equal to that of a. iin of greater width than the one shown. Heat transfer capacity with equal use of iin and tube materials s'gx'eater,

however, 'than that of a rectangular iin of thev same area because a kindfcf accumulation dome between the air entrance opening and heating unit isV provided, "serving to bring about more even flow of air through the heatingunit in terms of depth of the unit.

For strengthening and reinforcing the end edges of the iins, horizontally extending metal purposely made lunsymmetrical, with kthe apexV portionof its fln surface disposed behind a vertical linea--a drawn midway within the depth of the unit.- The middle `tuberlt' is disposedat the apex portion of the fins and behind said line af-a. The other tubes are disposed adjacent' the I ends of the uns. .As a result thegreatest amount of heat transference from the tubes and iins is concentrated toward the rear of the cabinet. 'I'he f air being free to enter the 'cabinet only atiits lower front end, in passing through the unit the I air tends to concentrate, in its passage, more at 'the rear of the unit than at the front.' In this form of the invention the tubes are unsymmetrical in distribution,A primary heat transfer thus being weighted to accommodate the greater concentration of secondary heat transfer surface at the rear of the heating unit.

In the modified form illustrated in Fig. 4 an unsymmetrical distribution of both iin and tube material is shown, with purposely greater weighting of these materials toward the rear of the heating unit, to serve the purpose of fitting the distribution of these materials to the inherent tendency of air passing through a convector heat ing unit to concentrate/toward the rear thereof. In this illustration the ns ISb are shown with unparallel top and bottom edges with the greatest width disposed at the rear of the unit. The tubes I5 are also unsymmetrically disposed, the middle tube being located to the rear of the median vertical line of the unit.

The shapes of the ns and locations of the tubes illustrated and described are merely exemplary of the principle and other fin shapes and tube locations might be employed to exploit this principle. The principle is that of employing to a uniform advantage and to the fullest advantage the tube and fin materials of a convector heating unit by strategic symmetrical or unsymmetrical in depth distribution'of tube and n materials, thus fitting the distribution of these materials to the inherent tendency of air passing through a convector heating unit to concentrate toward the rear in depth of the heating unit in its passage therethrough. The fin shapes may vary with the overall depth of the heating unit, inasmuch as the air entrance opening height is generally a constant and whereas the convector unit depths are varied in order to obtain variable capacities of convectors within fixed convector length and convector height dimensions.

The fin illustrated in Fig. 4 mayl be inverted if desired so as to have the upper edge extend in a horizontal direction, but with the weight of materials nevertheless most heavy behind a vertical line drawn midway between the depth of the heating unit; by such inverting, the center of gravity of heat transfer metal would be slightly lowered and hence the net chimney or stack height, causing flow of air through the 'convector to be slightly increased.

The heater may be set in a niche in a wall as shown or may be placed against a Wall of a room.

In the several forms of heating unit disclosed, an edge of the fin, either top or bottom edge or both inclines or slopes from the middle toward the front and rear or from front toward the rear. These lines may be straight or curved Yor angle shaped.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence, I do not Wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described or uses men'- tioned.

What I claim as new and desire to secure by Letters Patent is:

1. The combination with an enclosure having ers connected by tubes, and inverted V-shaped fins traversing said, tubes with their apexes disposed closer tothe rear of the enclosure than the front thereof, and there being a greater proportion of tubes adjacent the rear lof the enclosure than at the front thereof.

2. In a convector heating unit, an enclosure having an air inlet opening at its lower end, headers therein, a plurality of tubes connecting said headers and disposed in an unsymmetrlcal inverted ,V-shaped formation, and a multiplicity of unsymmetricalv inverted V-shaped ns traversing said tubes and being bonded thereto there being a greater distribution of tubes adjacent an air inlet opening adjacent -the lower end of its front wall, and a discharge air opening adjacent the upper end of the said wall, of a convector heating unit supported in said enclosure entirely above the air inlet opening and comprising head- Number Name Date 1,345,591 Fulton July 6, 1920 1,778,538 Trane Oct. 14, 1930 1,863,056 Kuenstler June 14, 1932 1,882,719 Armstrong etal. Oct. 18, 1932 1,941,705 Mertzanoi Jan. 2, 1934 2,055,549 Modine Sept. 29, 1936 2,065,873 Ruff Dec. 29, 1936 FOREIGN PATENTS Number Country Date 186,934 Switzerland July 18, 1935 the rear of the enclosure than at the front thereof.

3. In a convector heating unit, an enclosure having an air inlet opening at its lowerend, headers therein, a plurality of unsymmetrically arranged tubes connecting said headers, there being a greater distribution of tubes adjacent the f rear of the enclosurefthan at the front thereof,

and a multiplicity of ns traversing said tubes with the greater portion of their heat transfer capacity disposed at the rear side of a vertical line bisecting the unit.

4. In a convector heating unit having a front wall and a rear Wall and there being an inlet opening at the bottom of the front wall and an outlet opening adjacent the top thereof, headers, a plurality of tubes connecting said headers and disposed in an unsymmetrical inverted V-.shaped formation with the'greater portion thereof disposed adjacent the rear Wall, and a multiplicity of unsymmetrical inverted V-shape fins traversing said tubes and bonded thereto with the greater heat transfer capacity disposed adjacent the rear wall. a

5. In a convector heating unit, headers, a plurality of tubes connecting-said headers, and a multiplicity of ns traversing said tubes, said ns increasing in Width from front to rear of the unit, whereby the greater heat transfer capacity of the ns is disposed adjacent the rear Wall.

6. In a convector heating unit, headers, a plurality of tubes connecting said headers, and a multiplicity of fins traversing said tubes, said ns being in the form of trapeziums with their unparallel edges running from front to back of the unit, and the greatest width of the ns being disposed at the rear of the unit whereby the greater heat transfer capacity of the ns is disposed adjacent the rear wall.

ARTHUR G. DIXON.

REFERENCES CITED file of this patent:

UNITED STATES PATENTS