US2269050A - Chimney cap - Google Patents

Description

Jan. 6, 1942. E. VZIMMERMAN 2,269,050

CHIMNEY CAP Filed Nov. 1, 1939 Zmventor Emil Zjmmbrm 012 3g I aw, 4'. 0g,

(Ittorneg Patented Jan. 6, 1942 UNITED STATES PATENT J OFFICE;-

p fcnnvnvavcn Emil zinimerman, Everett, Wa'sln U Application November 1, 1939, Serial no. 302,354. 7 j I 10 Claims,

My invention relates to a chimney cap, that is, a device intended for application to-the'upper end of a chimney or other flue pipe, for-,the dual purpose of preventing down drafts, which sometimes occur. from adverse wind oratmospheric conditions, and of employin the available wind, Whether strong or light, and from whateverdidicated, which so controls the movement of .the

rection, to assist in creating an upward draft, n

gree, assist in withdrawing the-'smoke-and gas from *the' flue. Such rotatable ,caps,however,- have certain definite and well known objections, not the least of which is that being exposed to the weather and being generally of inexpensive sheet metal construction, they shortly begin to rust and stick, and then are worse than'no'cap,

Devices for such purposes as heretofore known have also taken the formof concentric conical and frusto-conical structures in various combinations, surmounting the chimney; the surrounding' sleeves being open to the wind, the whole arranged with the intent that the wind entering at the lower end of such sleeves will pass out at the upper end and will tend to create something of an upward eductor effect, tending to withdraw the smoke and gas from the flue round about a central inverted conical deflector, but such devices have been found lacking in practical application' in that the 'windwill not follow the in-. tended path, but will tend to sweep generally horizontally around the conical deflector, wherefore its eductor effect is minimized, and whereby the: wind itself maytend, by eddy currents, to

interfere with the up draft, rather than t assist in creating the up dr g l provide a device for application as'an immovable cap to a chimney or other fluewhich, having no moving parts, is not subject to the objections attaching to the rotary caps, and which is so It is the object-of my invention; therefore, to

constructed as to avoid the drawbacks of the type windthat the wind iscaused to move through the. device in such away that it ishardly possible to create eddy currents or down drafts into the lime, and in such a way that the wind cannot sweep through the capin any'manner except such as will induce an upward draft through the flue; in other words, it is an object to produce a device for. sucha' purpose, which is. so constructed as to prevent, positively, mere sweeping through 'of the wind around andabout deflectors ina manner notintended, and not productive of the desired final up draft within the flue.

, It is a further objecttoprovide such a cap which while not rotary, i open in all directions,-

so that it will operate fromwhatever quarter the wind'pmay come, yet will function asin'tended, re,- gardless of thewinds direction; which ispositively ,closed against direct down drafts or through drafts of any sort; in which the internal partsjare protected and not likely tov collect rain water; in which the air currentsand the smoke currents are guided and afforded ample passage areas; andhwhich, may besimply and ruggedly constructed, of sheet metal, and which may therefore be inexpensively constructed.

With .these and other objects in mind, as will appear as the specification progresses, my inventioncomprisesthe novel chimney cap and the novel, construction and arrangement ,of the several parts thereof, as shown in the accompanym drawing in a preferred form, and as will be morefully, disclosed in thisspecification and definedby the claims.

Figure 1 isa top plan Viewwith'parts broken Figure 3 is an isometric view, with parts broken away to illustrate the interior construction. The'device is formed as an upstandinglcollar l, vvhich ispreferably of square or rectangular form incross section, to fit upon and extend upwardly from the chimney 9. At its base it may be variouslyformed to ,fitupon the. chimney,,as

for instance by providing it with the sleeve Ill. The particular formation of the collar in, this re spect islimmaterial. It only to be noted that it is carried by and extends upwardly from the chimney 9, substantially in line with the chimney flue 9|, and that the collar, being ofv sheet metal, anclof aboutthe cross-sectional area of the exterior of thechimney, has an internal cross-secti-onalarea considerablyin excess of the area At its top the collar I is closed by a plate or top I2, which is preferably relatively flat, so that it creates no appreciable change of direction of the wind flowing over it, and just below the top it is provided with openings I I in each of its four sides, for entrance of wind and for exit of wind and smoke. These openings lie in the upper half of the collar, and the total area of each is approximately equal to the cross-sectional area of the flue 9|. Instead of one continuous aperture II, several individual apertures may be provided, if preferred. It appears more desirable, however, to employ one individual aperture in each face or wall of the collar, rather than sever-- al smaller apertures in each wall.

In its interior the collar I is divided by twov partitions 2, which extend diagonally from, corner to corner, and therefore cross in the center of the collar, their junction forming a vertical centrally disposed line 2I.. These partitions 2 extend, unbroken and imperforate, from the top plate I2 downwardly to a level at below the lower edge of. the apertures I I. They divide the upper portion of the interior of the collar into four sectors, and each of these sectors has, in the side wall of the collar, one of the apertures II, but only one. such aperture; A hollow, inverted, pyramidal deflector 3., formed of sheet metal or the like, is centrally disposed within the collar, the marginal edges of its. base being spaced from the adjacent walls of th collar preferably, to provide smoke outlets of ample cross-sectional area as compared to the flues cross section, and these marginal edges 30 are located above the lower edges 20 of the partitions 2, but preferably below the lower edges of the apertures II so that the sides of the pyramid are inclined upwardly and outwardly in alignment with the corresponding apertures, the drawing showing such deflector sides directed toward substantially the center of such openings. Th margins 30, therefore, lie. between the lower edges 20 of the partitions and the lower edges of the apertures II. The interior of this pyramidal deflector 3 admits to each one of the sectors de-' fined by the cross partitions 2, yet its margin 30 is above the bottom 20 of each sector. The term pyramidal is used generically to embrace pyramids having any number of. sides, unless otherwise specified, so that it would include a conical shape,.since a cone is merely a special type of pyramid, namely, a regular pyramid having. an infiinite number of triangular lateral surfaces.

Preferably a four sided pyramid is used, as shown,

with each edge 30 disposed parallel to a side of the square or rectangular collar I.

As a refinement, preferably employed, curved baffles 4 may be provided in each sector, curving inwardly and downwardly from the upper edge of each aperture I I towards the. junction of the line 2| with the lower edges 2a of the partitions, or towards the apex of the deflector 3. Though it. is considered undesirable to permit the partitions 4 These baflles 5 serve to entrap and direct inwardly air which might otherwise pass over the top of the cap, and they serve much as do awnings to deter or prevent the entrance of rain water.

Smok rising from the flue 9| will tend, if not acted upon by air currents or down drafts, to divide at the deflector 3 and to pass out on all sides thereof and into each one of the sectors, and thence out through the apertures II. However, if the air is moving, whether the wind be light or strong, it tends to enter as indicated by the arrow A in Figure 2, and for the moment we may assume that the air direction is perpendicular to the face of the collar which contains the aperture at the left of Figure 2. The air entering at A isv deflected downwardly and caused to converge into the angl of the partitions 2 by unbroken partitions and the curved interior baffle 4. However, it moves inward sufliciently that it passes inside the margin 30 of the deflector 3, and has no appreciable tendency to pass downward between this margin 30 and the left-hand wallof the collar. Entering the deflector 3, it can only escape by reversing its direction and moving upwardly, as indicated by the arrow B, and then in the opposite sector, at the right, it tends to pass out through the upper portion of the aperture II, as indicated by the arrow C, being aided in its change of direction by the wall of the deflector 3 and by the curved interior baflle 4 inthe right-hand sector. Thus its direction is necessarily upward and outward, and it thereby entrains the smoke from the flue 9|, which now tends to rise into the right-hand sector, as indicated by the arrow D, and this smoke, directed outwardly by the side of the deflector, passes out of the lower portion of the aperture II as indicated by the arrow E, aided by the aspirating effect of the air also passing through the aperture. The cross-sectional areas of the restricted portions of these passages are sufficient to afford the movement of air or smoke as indicated, without appreciable restriction of flow nor tendency to eddy.

While opposite sides of the collar preferably are disposed parallelto the prevailing wind, the direction of the wind is not always perpendicular to any given face or wall of the collar I, but at times will be at an angle thereto. Let us assume to extend. below the level of the edge 2-0,, yet, it is that it is at and thus equally strikes two adjoining perpendicular walls of the collar. It tends to enter the aperture II in each of these walls, but can not pass immediately through and out the apertures in the opposite walls, because it is intercepted and blocked by the imperforate diagonal partition 2, and is directed downwardly by the curved interior baflies 4, and is caused to converge to the junction 2| of the partitions 2, wherefore it is caused to enter the conical deflector 3, and to pass downwardly thereinto, and then upwardly again, but at the opposite side of the partition first encountered. Passing upward only at the, opposite side of; this partition, this wind can only pass out of the apertures I I- at the opposite side of such; p rtition. Thus it follows, fromthe use of the cross partitions 2, that the air musta-lways. wholly or certainly in. a m jor part, pass into, the, conical deflector 3, before it can pass upwardly, that it can only pass upwardly because it is so, directed and because the only escape is, above, and when it passes upward- 15 it, can only pass outwardly at the opposite side of thepartition or partitions which barred its through passage; from all this it follows that the wind, in escaping, must entrain smoke from the flue 9|. Down drafts are thus prohibited, and the wind, whether light or heavy, will automatically and of necessity entrain upward movement of the smoke. I c

What I claim as my invention is:

1. A chimney cap comprising a collar formed as an upward extension of the chimney, and closed at its top, having openings in all its sides adjacent its top, upright partitions extending across the interior of the collar, subdividing it into at least four sectors, the partitions extending from the closed top downwardly to a level below said openings, and being imperforate throughout such extent, whereby communication between sectors can be had only beneath the partitions, and a hollow, inverted pyramidal deflector disposed with its apex spaced beneath the juncture of the partitions, the edges of said pyramidal deflector being disposed above the level of the lower edge of the partitions, and inwardly from the walls of the collar, to leave an annular smoke passage, and such edges being further disposed outwardly of the juncture of the partitions, to direct air which enters at one opening downwardly at the corresponding side of the partitions and then upwardly at the other side thereof, for discharge with entrained smoke, through an opening at such other side. I

2. A chimney cap comprising a collar formed as an upward extension of the chimney, and closed at its top but laterally open on all sides adjacent its top, imperforate partitions fixed within the collar, extending from its closed top downward completely through and to a level below its laterally open portion, and intersecting at about the center line of the collar to divide the same lengthwise into at least four substantially equal sectors, and a hollow, inverted pyramidal deflector disposed with its apex spaced beneath the junction of the lower edges of the partitions, and with its basal edges extending between adjacent partitions, and spaced from the adjoining collar wall to afford a smoke passage from the flue beneath, in each sector.

3. A chimney cap comprising a collar formed as an upward extension of the chimney, and closed at its top but laterally open on all sides adjacent its top, imperforate partitions fixed within the collar, extending completely through its laterally open portion and downward below such portion, and dividing the collar lengthwise into at least four sectors, a hollow inverted pyramidal deflector disposed with'its apex spaced beneath the partitions, and with its basal margin above the lower edges of the partitions, and spaced inside the walls of the collar, to afford a smoke passage from the flue beneath into each sector, and a bafile in each. sector curving from a point adjacent the upper edge of each opening inwardly towards the partitions forming such sector and downwardly at least to a location substantially even with the lower edge of the collar opening.

4. A chimney cap comprising a collar closed at its top, and formed as an upward extension of the chimney, and laterally open on all sides adjacent its top, two imperforate vertical partitions fixed in intersecting relationship within the collar, extending from its closed top downwardly through its laterally open portion and to a level below the lower edge of the collar opening, dividing the collar lengthwise into four sectors, and a hollow inverted pyramidal deflector disposed with its apex spaced beneath the intersecting line of the partitionsand with its sides lying in planes which are directed upwardly and out-" wardly to intersect the collar in a line substantially above the lower edge of the corresponding collar opening, the defiectors sides stopping short of the collar to dispose the deflectors upper edges above the lower edges of the partitions but below the lower edges of the openings, and spaced inside the walls of the collar, to afford a smoke passage from the flue beneath said deflector through each sector directed outwardly toward the collar opening.

5. A chimney cap comprising a collar which is rectangular in cross section, formed as an upward extension of the chimney flue, said collar being closed at its top but laterally open at the top of each wall of the collar, two imperforate, diagonal, vertical, fixed partitions extending from its top closure downwardly and from corner to corner within the collar, crossing at its center, and dividing the collar lengthwise into four sectors, and an inverted, hollow, rectangular pyramidal deflector disposed with its apex spaced below the junction of the partitions, and with its basal edges above the lower edge of the partitions, each base edge of the deflector bridging between the adjacent partition portions and disposed parallel to and spaced from the collar wall in a sector to afiord a smoke passage from the flue beneathinto each sector.

6. A chimney cap comprising a collar which is rectangular in cross section, formed as an upward extension of the chimney flue, said collar being closed at its top but laterally open at the top of each wall of the collar, two imperforate, diagonal, vertical, fixed partitions extending from its top closure downwardly and from corner to corner within the collar, crossing at its center, and dividing the collar lengthwise into four sectors, an inverted, hollow, rectangular pyramidal deflector disposed with its apex spaced below the junction of the partitions, and with its basal edges above the lower edge of the partitions, each base edge of the deflector bridging between the adjacent partition portions and disposed parallel to and spaced from the collar wall in a sector, to afford a smoke passage from the flue beneath into each sector, and a baflie in each sector curving from the upper edge of each collar opening inwardly into the angle between the partition portions forming such sector and downwardly at least to a location substantially even with the lower edge of the collar opening.

7. A chimney cap comprising a collar which is rectangular in cross section, formed as an upward extension of the chimney flue, said collar being closed at its top but laterally open at the top of each wall of the collar, two imperforate, diagonal, vertical, fixed partitions extending from its top closure downwardly and from corner, to corner within the collar, crossing at its center, and dividing the collar lengthwise into four sectors, an inverted, hollow, rectangular pyramidal deflector disposedwith its apex spaced below the junction of the partitions, and with its basal edges above the lower edge of the partitions, each base edge of the deflector bridging between the adjacent partition portions and disposed parallel to and spaced from the collar wall in a sector to afford a smoke passage from the flue beneath into each sector, and a baffie for the collar opening including a portion in each sector curving from the upper edge of each collar opening inwardly into the angle between the partition portions forming such sector and downwardly at least to a location substantially even with the lower edge of the collar opening, and also a portion extending from the collar upwardly and outwardly in continuation of said first baffle portion.

8. A chimney cap comprising a collar formed as an upward extension of the chimney, and closed at its top, having openings in all its sides adjacent its top, upright partitions extending across the interior of the collar subdividing it into at least four sectors, the partitions extending from the closed top downwardly to a level below said openings, and being imperforate throughout such extent, whereby communication between sectors can be had only beneath the partitions, and a hollow, inverted pyramidal deflector disposed with its apex spaced beneath the juncture of the partitions, the edges of said pyramidal deflector being disposed above the level of the lower edge of the partitions, and inwardly from the walls of the collar, to leave an annular smoke passage, and such edges being further disposed outwardly of the juncture of the partitions, to direct air which enters at one opening downwardly at the corresponding side of the partitions and then upwardly at the other side thereof, for discharge, with entrained smoke, through an opening at such other side, and a baflie in each sector curved, from a level with the upper edge of the corresponding opening, inwardly and downwardly, and disposed generally transverse to air entering at such opening, to direct air entering by such opening inwardly and downwardly towards the apex of said inverted pyramidal deflector, or to direct air rising from such deflector outwardly through such opening.

9. A chinmey cap comprising a collar formed as an upward extension of the chimney, closed at its top, and having openings on all sides adjacent its top, relatively crossed upright partitions extending diametrically from side to side across the interior of the collar, and from its top closure downwardly to a level below the collars openings, and being imperforate throughout such extent, said crossed partitions dividing the interior of the upper portion of the collar into sectors, between which communication can only be had beneath the lower edges of said partitions, and a hollow, inverted pyramidal deflector disposed with its apex spaced beneath the juncture of the partitions, and with its sides directed upwardly and outwardly towards the openings, but terminating in edges which are spaced above the lower edges of the partitions but not above the lower edges of the collars openings, and intermediate the side walls of the collar and the juncture of the partitions, thus to define smoke passages from the flue between the deflectors edges and the collars side walls, and to define a separate passage, first directed downwardly and then upwardly, for air which enters at an opening at one side of the collar, and directing it outwardly through the opening at the other side thereof.

10. A chimney cap comprising a collar formed as an upward extension of the chimney, and closed at its top but laterally open on all sides adjacent its top, imperforate partitions fixed within the collar and dividing it into at least four sectors, a hollow, inverted pyramidal deflector disposed with its apex spaced beneath the partitions, and with its sides directed upwardly and outwardly towards the corresponding collar opening, but stopping short thereof to dispose its upper edges in spaced relation to the walls of the collar, to afford a smoke passage from the flue beneath said deflectors through each sector di-- rected outwardly toward the collar opening, and means between said partitions and the collar, disposed opposite each opening, operable to deflect air flowing in through any opening downward alongside a partition into said hollow inverted deflector.

EMIL ZIMMERMAN.

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