US2515467A - Ventilator for chimney stacks and the like - Google Patents

Description

y 8, 1950 o. w. PETERSON VENTILATOR FOR CHIMNEY STACKS AND THE LIKE Filed March 18, 1949 2 Sheets-Sheet l JNVENTOR. ORWIN W. PETERSON ATTORNEYS J 1950 o. w. PETERSON 2,515,467

VENTILATOR FOR CHIMNEY STACKS AND THE LIKE Filed March 18, 1949 2 Sheets-Sheet 2 l I IINIIHI 4 JNVENTOR.

ORWIN W. PETERSON ATTORNEYS Patented July 18, 1950 VENTILATOR FOR CHIMNEY STACKS AND THE LIKE Orwin W. Peterson, Denver, Colo.

Application March 18, 1949, Serial No. 82,228

This invention relates to ventilators for chimney stacks and the like.

Particularly when the wind direction changes quite frequently, or even when a hard wind is blowing, it often happens that a gust of wind, or even a sustained wind, will cause a down draft into a chimney, stack or the like. The resultant reverse flow of gases in a chimney or stack not only tends to interfere with burning or combustion, as in a furnace or'flreplace, but also may produce a fire hazard. The latter may be occasioned by sparks or live coals blown from a fireplace into a room, or by the extinguishment of a gas flame and the possible escape of unlit gas, with a consequent danger of explosion. Caps or covers, spaced upwardly from the stack or chimney top, have not solved the problem successfully, since a wind blowing across the opening at the top may tend to enter the chimney. Also, if one side of the chimney, as on that of the prevailing wind, is protected by a shield or the like, a change in wind direction tends to render such shield valueless,

Among the objects of the present inventionare to provide a novel ventilator for a chimney, stack or the like; to provide such a ventilator which will produce an up draft at the chimney or stack opening; to provide such a ventilator which will produce such an u draft, irrespective of wind direction or changes in wind direction; to provide such a ventilator'which can be easily and cheaply manufactured, and be made in various sizes so as to fit any desired stack or chimney; to provide such a ventilator which will contain a minimum of parts; to provide such a ventilator which will produce a minimum of'waste material during the manufacture thereof; and to provide such a ventilator which will require a minimum of time for the production thereof. Other objects and the novel features of this invention will become apparent fromthe description which follows, taken in connection with the accompanying drawings, in which;

Fig. 1 is a side elevation of a ventilator constructed in accordance with this invention, in stalled on the upper end of a chimney or stack plp Fig. 2 is a horizontalsection'taken along line 2--2ofFig.1;

Fig. 3 is a generally vertical section, with certain parts broken away, illustrating the interior construction of the ventilator'of Fig. '1;

Fig. 4 is atop plan view, on a reduced scale, of a skirt blank cut from 'a single sheet of material, such skirt forming a part of the ventilator of Fig. 1; and

Fig. 5 is an enlarged transverse section taken through a lock joint, at which the ends of the skirt blank are attached together.

' A v ntilator constructed-i a ordance with 7 Claims. (Cl. 9878) this invention, as illustrated in Figs. 1 and 2, may comprise a top T and a skirt S, or outer wall, mounted one above the other and installed on a chimney or stack pipe P, which also may be termed an inner member. The pipe P will normally be formed of sheet metal or the like, and is also usually circular in form, although the ventilator of this invention may be installed on chimneys, stacks or pipes having other than a circular cross section. The skirt S is generally tubular but is larger in diameter or size than and extends in spaced relation to the pipe P, both above and below the top ID of pipe P, and may diverge slightly from top to bottom. In accordance with this invention, the lower portion of skirt S, spaced below the top of pipe P, is provided with a series of air channels or scoops l I, such as four in number, and preferably equally spaced about the periphery thereof, as apart, each air channel I I extending generally upwardly from the bottom of the skirt S toward the top H! of the pipe P, but terminating below the top In. Each air channel I I is adapted to catch and then direct wind and air currents toward and then around and upwardly from the pipe top Ill. The current of air produced by a channel H will tend to carry hot gases or smoke from the pipe P, along with it, in the enlarged space within skirt S above pipe top It, as by a suction effect.

Each air channel II is bounded by a forwardly inclined and radially extending edge l2 to provide an exterior opening, into which wind or air currents flow from primarily one direction only, andmay be formed by a flange l3 which has a transversely curved bottom or rear wall and which extends inwardly at an angle and then upwardly along the pipe P. Each flange I3 is preferably integral with skirt S, although one or more'may be formed separately and attached'to the skirt. Also, the skirt S is preferably cut away at each flange I3, to form the edges l2, each of which is downwardly inclined and slopes in a direction with respect to the vertical, which is opposite to the direction of slope ofthe'bottom of the air channel. The flange l3 'foreach air channel, as in Fig. 3, is preferably formed. by a generally trapezoidal tongue I4, shown in extended position in dottedlines in Fig. 3, which is bent upwardly and inwardly so that the point l5 thereof can be lappedover onto the upper end ID of pipe P. The upper inside section l6 of tongue I4 is also preferably formed to flt against the pipe P. i

As will be evident from Figs. 1 to 3,'inclusive, the'wind or air current blowing into one of the air channels II is conducted interiorly of the skirt and past the pipe top 10, but each of the other air channels I I will tend to prevent'or retard the flow of air thereinto, so that for any particular wind direction, one orperhaps two air channels II will receive the air current. Due to the substantially equal spacing of the air channels II, and the capacity of each air channel to catch wind or air current blowing primarily in one direction only, or from one side of the chimney or stack, whenever the wind direction changes or shifts, as through approximatel 90 degrees, the previous air channel will tend no longer to conduct the air, but one of the other air channels will catch and direct the air upwardly, and around the pipe top 10. As will be evident, there will thus always be one or more air channels [I to receive the wind or air current, irrespective of the wind direction.

The top T of the ventilator may be formed from a pair of frustro-conical plates l8 and [9, respectively, plate It being disposed in upright position and its outer edge preferably having a greater diameter than the skirt S. The plate I9 is inverted within the plate I8, the outer edge of plate l9 preferably engaging the plate 88 and having a diameter slightly less than that of the upper edge of skirt S. The plates is and [9 are preferably attached together in any suitable manner, as by spot welding, each preferably being formed from a single sheet bent or rolled around to final shape and the edges then attached to-- gether, as by riveting or welding, although each of the conical plates l3 and i9 may be formed from a solid sheet or plate extruded or otherwise formed from flat plate. The top T is supported in spaced position above the skirt 3, as by a series of relatively narrow supports 20, such as three or four in number. The lower ends of supports 20 may be attached to the upper edge of the skirt S by metal screws 2|, or in any other suitable manner, as by riveting, spot welding or the like. Also, the upper ends of the supports 20 may be bent to conform to the shape of one of the plates 18 or H), and attached thereto by riveting, spot welding or by metal screws or the like.

The space between the upper edge of skirt S and the top T is preferably such that the current of air directed upwardly from one or more of the air channels H and the gases from pipe P will strike the smaller plate 18 and be deflected outwardly from underneath the larger plate l9, it being understood, of course, that the wind or natural air current blowing between the skirt S and top '1 will tend to carry off smoke and hot gases from pipe P, along with the air current from the channel I l to the leeward side.

In further accordance with this invention, the skirt S is preferably made from a single sheet in a, simple, effective and economical manner, as

in Fig. 4, which is shown on a reduced scale in comparison with Figs. 1-3. The sheet is preferably cut so that an upper are 23 will have a length equal to the circumference of the upper edge of the skirt S, while the ends 24 and 25 extend radially from the are 23, allowance being made for the ends to lap over and form a joint, such as the lock joint 26 of Fig. 5. The lower are 21 of the sheet of Fig. 4 is preferably laid out from the same center as the upper are 23, and spaced radially a sufficient distance to accommodate not only the vertical height of the skirt '3, but also additional material to form the tongues 14, which are produced by triangular cut-outs 28. The upper end points 29 of the triangular cut-outs 28 are preferably spaced equidistantly from each other, and from the end 25 of the sheet. The longer edge 30 of each cutout 28 preferably extends from the upper end point 29 to a point on the lower are 21 radially beneath the next adjacent point 29, while the shorter edge 3| of each triangular cut-out diverges from the longer edge 30 at a suitable angle, depending upon the relative size of the skirt and the size and shape of the air channels II to be produced. After the skirt sheet has been cut out, the ends 24 and 25 are lapped over and locked together, one or more rivets also being utilized if desired. The central portion of each tongue 14 is bent around in a suitable curve, starting along a line generally perpendicular to the longer edge 30 of the adjacent cut-out, such as alon the dash lines 32. Prior to or at the time of installation of the ventilator, the point I5 of each tongue may be bent over and clinched on the pipe top H), each point I5 being bent along a suitable line, such as the dash line 33 of Fig. 4. The shorter edge 3| of each cut-out, as in Fig. 3, will then extend vertically along the wall of pipe P, and each tongue or flange l3 may be fastened to the pipe adjacent to the lower end of edge 3|, as by a metal screw 34 of Figs. 2 and 3, or in any other suitable manner. The holes for the metal screws may, of course, be drilled prior to installation of the ventilator on the pipe, although the position and number of screws may be varied, as desired. Preferably, skirt S is cut out, attached together, the tongues I4 bent to shape, and the top T attached thereto, prior to installation of the ventilator on the pipe P. However, if desired, the ventilator may be made directly on a section of pipe, which may then later be placed in or installed on the stack or chimney.

Instead of the tongue M adjacent end 24 requiring a portion of the lock joint, the tongue may be made at the left, such as the tongue l4, shown in dotted outline; and the tongue I l at the right omitted, the sheet being cut away along the dotted extension 35 of the adjacent edge 3|. In this way, it is unnecessary to form the lock joint 26 across one of the tongues 14. The shaping and installation of the skirt, with the tongue I4, is essentially the same as described above.

For laying out the skirt sheet, as in Fig. 4, whenever a number of skirts or ventilators of the same size are to be made, it will be advantageous to make a template of the correct size and shape, for laying out a number of skirts, either on separate sheets or plate or the same sheet or plate. Or, a larger template including a number of skirt layouts may be made. Of course, when the quantity to be produced warrants, dies for cuttin out the skirt sheets by machine may be made. Both the skirt S and top T of the ventilator may be made of suitable material, such as from galvanized steel sheet or plate, or other metal, such as aluminum, copper, etc. Normally, the ventilator will be made of the same or similar material .as the pipe P, but this is not always necessary. Also, the ventilator may be made on a section of the pipe P. in the shop, and the section then attached to the remainder of the pipe, as by a conventional interfitting slip joint or the like.

From the foregoing it will be evident that the ventilator of this invention fulfills to a marked degree the requirements and objects hereinbefore set forth. The operation of the ventilator is not affected by changes in wind or air current direction or velocity, since even the most varying and whipping gusts will usually not change the production of the upwardly directed air current which travels through one or more channels H,

and upwardly and around the pipe top I0. Also, any change or shift in wind direction will merely cause another of the channels II to produce the desired upward current inside the skirt, instead of the channel il into which the wind previously passed.

The production of the ventilator of this invention is quite simple and economical. A minimum of labor and assembly cost is involved, since the parts are few in number, assembly requires only a few rivets or metal screws, and installation requires only the placement of a few metal screws or the like. The utilization of the tongues M to form not only the air channels I I, but also to attach the ventilator to the pipe P in a sturdy yet simple manner, contributes considerably to the low cost of manufacture. The production of the skirt S from a single sheet of metal, merely by making a few triangular cut-outs, after properly shaping the edges, lends itself to maximum production operations, since the skirts can be cut out in quantities by dies, if desired. Since chimney pipes come in a few generally standard sizes, it will be necessary only to make up a template for the skirt S of each specific size, and the time required to produce the skirt from the template should be very small indeed. The shaping of the tongues to form the air channels 1 l is a relatively simple operation, since the sheet may be held in place by a jig or the like, and the tongues I4 bent up in turn, either to engage the edge of the pipe P on which the particular ventilator is being installed, or to engage a dummy pipe, for purposes of manufacture.

As will be evident, there is relatively little scrap in the sheet from which the skirt S is made, and a minimum of attaching screws and the like is necessary. Also, the curvature of the tongues is not complicated, and there are no really diflicult geometrical patterns to produce. It will be understood, of course, that the skirt S may be made from more than one piece of metal, if desired, such as two or more pieces attached together, although production from a single sheet involves less labor time. However, if a relatively large ventilator, such as several feet in diameter, is to be produced, it may be desirable to make the skirt from more than one piece of metal, and also add stiffening bars or angles, if advantageous.

Although a specific embodiment of this invention has been illustrated and described with particularity, and various changes indicated, it will be understood that other changes may be made therein, and also that other embodiments may exist, all without departing from the spirit and scope of this invention.

What is claimed is:

1. A ventilator for a stack or the like, comprising an inner tubular member; a generally tubular outer wall mounted in spaced encompassing relation to said inner member, said wall extending upwardly to a point above the upper end of said inner member and downwardly to a point below the upper end of said inner member; and a plurality of flanges extending from the lower end of said wall generally inwardly to said inner member and then upwardly along said inner member and secured thereto, each said flange extending downwardly, then inwardly and upwardly at an angle between said wall and inner tubular member, so as to form an air channel between said wall and inner member, said flanges being spaced apart to form inlets for said air channels.

2. A ventilator for a stack or the like, as defined in claim 1, wherein said outer wall is cut away at each said flange to form a downwardly inclined edge sloping in a direction with respect to the vertical, opposite the direction of slope of said air channel bottom with respect to the vertical.

3. A ventilator for a stack or the like, as defined in claim 1, wherein the upper end of each said flange is bent over the top of said inner member.

4. A ventilator for a stack or the like, as defined in claim 1, wherein the highest point of the inwardly extending portion of each said flange is spaced below the upper end of said inner member.

5. A ventilator for a stack or the like, as defined in claim 1, wherein each said flange is integral with said outer wall.

6. A ventilator for a stack or the like, as defined in claim 1, wherein said flanges are four in number and circumferentially spaced apart.

7. A ventilator for a stack or the like, comprising an inner tubular member; a generally tubular outer wall mounted in spaced encompassing relation to said inner member, said wall extending upwardly to a point above the upper end of said inner member and downwardly to a point below the upper end of said inner member; a plurality of flanges extending from the lower end of said wall generally inwardly to said inner memher and then upwardly along said inner member and secured thereto, each said flange extending downwardly, then inwardly and upwardly at an angle between said wall and inner tubular member, so as to form an air channel between said wall and inner member, said flanges being spaced apart to form inlets for said air channels; and a top mounted on the upper end of said wall and extending laterally beyond said wall.

ORWIN W. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 199,399 Barnum Jan. 22, 1878 1,074,143 Vaughn et al Sept. 30, 1913 1,489,886 Hart et al Apr. 8, 1924 1,545,618 Sundahl July 14, 1925 1,849,812 Spencer Mar. 15, 1932 FOREIGN PATENTS Number Country Date 3,198 Great Britain Feb. 13, 1893 10,514 Great Britain 1886 821,078 France Aug. 17, 1937

Images