Louver Assembly

Abstract

An assembly of louver blades attached to a frame for positioning in a ventilating opening provided in the wall of a building and defining an air handling device through which air is free to flow. The louver blades may be disposed in either horizontal or vertical orientation. The flowing air traverses passageways defined by the louver blades, and eventually exits said passageways on the side opposite of its original entrance. Raindrops, which may have accompanied the air stream as airborne free water, are extracted to an acceptable degree through natural gravitational forces and other means whereby said water is caused to be deposited upon the surfaces of the louver blades. Drainage means are provided whereby the water is effectively drained from the louver blades to the exterior of the louver assembly and falls harmlessly to the ground.

Description

BACKGROUND OF THE INVENTION

Ventilating louver assemblies are frequently used in cooperation with air conditioning systems of buildings to insure the circulation of clean, unadulterated air. Commonly, such louver assemblies are installed in a ventilation opening in the wall of a building, communicating with the outside atmosphere and the interior of the building to provide clean, fresh air directly to the building interior. To operate efficiently, such louver assemblies must allow the free passage of air in order to provide the volume of air required. However, as the exterior of the louver assembly is exposed to normal weather conditions, the louver assembly must be adapted to prevent natural elements such as rain and mist from passing through the assembly to the interior of the building.

Louver assemblies of the prior art have met with only limited success in accomplishing these objectives. A louver assembly having a series of complex passageways will effectively prevent mist and rain from passing; however, the free passage of air is also inhibited. For example, see U. S. Pat. No. 3,358,580 to Freese et al, and U. S. Pat. No. 1,896,656 to Anderson. The turbulence producing protrusions and generally zig-zag air passageways of louver assemblies of the prior art restrict to a varying degree the free passage of air, thus creating a substantial difference in atmospheric pressures on the opposite sides of the louver assembly. See U. S. Pat. No. 3,348,466 to Lane et al. Fans, blowers and the like that may be associated with such louver assemblies have relatively high power requirements in order to draw air through the complex passageways.

SUMMARY OF THE INVENTION

This invention relates to a louver blade and to a louver assembly comprised of a plurality of said louver blades assembled in a suitable frame for positioning in a ventilation opening provided in the wall of a building. The louver assembly satisfies demands for low air frictional resistance or pressure drop and greatly improved means of extracting free water from air passing through the louver assembly over a wide range of atmospheric conditions. The louver assembly of the present invention accomplishes these results through the use of louver blades cooperating to define generally C-shaped air passageways. Each blade has a first primary and a second minor integral hook-like extension or protrusion which extends partly into the air stream in a direction to cause maximum moisture removal from the passing air while inducing minimal turbulence in the air. There is no reduction of constriction in the air passageways once the air has passed through the first or outside opening, whereby the air velocity is only minimally reduced below the velocity at the point of entry into the louver assembly. Air-borne free water drawn into the passageway from the outside is primarily deposited upon a first canted surface of the louver blade and held from blowing over the blade apex by the primary hook-like extension running the full length of said blades. Splash droplets and resulting mist bypassing the primary extension are thrown from the passing air stream due to centrifugal forces generated as the air stream is forced to change its direction at the apex of the passageways. These droplets impinge upon a surface of the rear blade portion and are directed to the second hook-like extension where means are provided for draining the water away. In a first embodiment of the invention, the louver blades are disposed in a generally horizontal orientation. In a second embodiment of the invention, the louver blades are disposed in a vertical orientation. Fans or blowers or the like associated with the louver assembly have relatively low power requirements due to the free flow of air provided by the louver assembly.

An object of the invention is to provide a louver assembly allowing free and uninhibited passage of air. A second object of the invention is to provide a louver assembly effecting efficient removal of free water accompanying passing air. A further object of the invention is to provide elongated blade louvers for such a louver assembly cooperable in pairs to define air passageways and having protruding extensions projecting partially into said passageways to effect efficient removal of water from passing air. A further object of the invention is to provide an elongated blade louver of the type described being equally effective in a horizontal or vertical orientation.

IN THE DRAWINGS

FIG. 1 is a front elevational view of a horizontal louver assembly installed in a building having plate louvers according to the present invention;

FIG. 2 is a sectional view of the louver assembly of FIG. 1 taken along the line 2--2 of FIG. 1;

FIG. 3 is a top sectional view of the louver assembly of FIG. 1 taken along the line 3--3 of FIG. 1;

FIG. 4 is an enlarged cross-sectional view of a blade louver of the invention;

FIG. 5 is an elevational view of a vertical louver assembly installed in a building;

FIG. 6 is a side sectional view of the louver assembly of FIG. 5 taken along the line 6--6 of FIG. 5; and

FIG. 7 is a top sectional view of the louver assembly of FIG. 5 taken along the line 7--7 of FIG. 5.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the drawings, there is shown in FIGS. 1 through 4 a first preferred embodiment of the invention. A louver assembly, indicated generally at 9, includes a plurality of longitudinal elongated blade louvers of the invention, preferably of extruded metal, functionally assembled in a horizontal configuration, disposed in a ventilation opening provided in a wall 10 of a building. The louver blades 11 are assembled in a frame, indicated generally at 12, arranged in horizontal parallel spaced relationship fixedly secured between outwardly open vertical right and left side channel members 13, 14. While five of the louvers 11 are shown, it is understood that more or less could be provided. Right and left channel members 13, 14 are provided with inwardly facing interior drain gutters 65, 66 respectively, which provide for the proper drainage of paints and processing chemicals used during the manufacture of the louver assembly. Inner splicing elements 15, 16 fit snugly within the channels of the respective channel members 13, 14 to reinforce the composite structure and facilitate the interconnection of additional louvers. On the side of the louver assembly facing the interior of the building, right channel member 13 defines a rear vertical drain gutter 18 open to the louver assembly. Likewise, left channel member 14 has provided a second rear vertical gutter 19 open to the louver assembly. Exterior end plates 20, 21 of the vertical side channel members 13, 14 have inwardly turned lips 22, 23 engaging the confronting surfaces of the wall opening. A top horizontal channel member 25 and a lower horizontal channel member 26, in conjunction with the vertical side channel members 13, 14, form the structurally rigid enclosure or frame 12 for the blades 11. The lower horizontal channel member 26 has an upper canted surface 80 inclined downward toward the exterior of the louver assembly. Right and left vertical gutters 18, 19 drain on to the canted surface 80 and to the exterior of the louver assembly. The components of the frame 12 may be fastened together by any usual or preferred means and, likewise, the frame 12 is retained in the opening in the wall 10 by usual or preferred means. The exterior wall of lower channel member 26, extending horizontally across the frame, provides a lower outer sill plate 27 for the louver assembly. Likewise, the interior wall of the lower channel member 26 provides a lower inner sill plate 28 for the louver assembly.

As shown by FIG. 2, louvers 11 of the invention cooperate in pairs, adjacent louvers together defining a generally C-shaped air passageway having an inlet passage 30, a transition passage 31, and an outlet passage 32. The C-shaped passageway has a lateral depth indicated by the line 33 in FIG. 3.

Each of the blades 11, as shown by FIG. 4, has an inlet plate or section 34 and an outlet plate or section 35. The inlet section 34 is generally flat and, when the blade louvers 11 are horizontally disposed, upwardly inclining from the building exterior, have an upper surface 37 and an opposite lower surface 38. Outlet section 35 inclines generally downward from inlet section 34 at an obtuse angle 49 relative to inlet section 34, and has an upper surface 40 and an opposite lower surface 41. As shown, the inlet section 34 is longer than outlet section 35. The inlet section 34 is disposed at an acute angle 43 relative to the vertical or frontal plane defined by the frame 12, and is connected to the outlet section 35 at a point intermediate of the length thereof when there is defined a major protruding extension or first exteriorly open hook-like extension 44. The first extension 44 is generally C-shaped and is constituted as an extension of the outlet section 35, having an outer lip 45 generally parallel to the upper surface 37 of inlet section 34 protruding into inlet passage 30.

Outlet section 35 is disposed at an acute angle 47 relative to the vertical plane of the louver assembly. A second rear minor portruding extension or hook-like extension 48 is formed at the rear edge of the outlet section 35 and projects into the outlet passage 32 of the air passage opposite the air passage in which the major extension 44 of the same louver 11 projects. Rear extension 48 includes a back portion 50 extending downwardly from the rear edge of the outlet section 35, a forwardly extending section 51 generally parallel to the outlet section 35 and extending inward from the back 50, and an angularly upturned lip 52 extending from the section 51. At either end of the louver assembly the second extension 48 communicates with the vertical gutters 18, 19, as shown by FIG. 3.

Formed integrally with inlet section 34 is a vertical weather stop or lip means 54 which preferably consists of flat metal strips of generally rectangular cross section. Lip means 54 extends horizontally along the front edge of inlet section 34. The lower edge 55 of weather stop 54 is angularly inclined at an obtuse angle 56 relative to the vertical plane of the louver assembly. The space between lower edge 55 of weather stop 54 and the adjacent louver 11 defines an inlet mouth 57. Similarly, back portion 50 of second extension 48 provides an integral rear stop. The C-shaped extension 44 has a portion extended through a plane defined by the ends of the lip 54 and second protruding extension 48 of an adjacent louver 11a.

Referring to FIG. 2, it may be seen that air inlet passage 30 is defined by the top surface 37 of the inlet section 34 of the louver 11 and the lower surface 38 of the inlet section 34 of an upper adjacent louver 11a. Likewise, the outlet passage 32 is defined by the top surface 40 of outlet section 35 of louver 11 and the bottom surface 41 of outlet section 35 of upper adjacent louver 11a. The width of the air passage provided by inlet passage 30, transition passage 31 and outlet passage 32 is at no point less than the inlet mouth 57 defined by the lower edge 55 of weather stop 54 and the front edge of the inlet portion 34 of the lower adjacent louver.

Those familiar with the louver art will appreciate that, in a louver assembly, the dimensions of the various components and their geometrical relationship are quite important in determining air flow behavior. The following table is offered to illustrate specific dimensions and trigonometric values of a particular blade designed for the louver assembly described herein. This blade has displayed outstanding performance over a wide range of air velocities, with simulated rainfall, in numerous laboratory wind tunnel tests.

TABLE A

Blade thickness Inches 0.081 Louver height Inches 72.00 Distance between blades Inches 2.00 Length of section 37 Inches 3.25 Length of section 40 Inches 1.156 Angle 49 Degrees 134 Angle 43 Degrees 71 Angle 47 Degrees 63 Angle 56 Degrees 109 Length of section 50 Inches 0.594 Length of section 51 Inches 0.438 Length of section 52 Inches 0.250 Length of section 54 Inches 0.688 Length of line 33 Inches 4.830

Primary extension section 44, a circular ring sector having:

An angle of Degrees 103.degree. - 12' An outside radius of Inches 0.500 An inside radius of Inches 0.419

It is to be understood that the above linear dimensions may vary directly in proportion to the length of line 33 and that effective results have been achieved by varying certain of the dimensions described above. For example, length of line 33 may be increased or decreased to satisfy certain conditions if the distance between the blades is altered proportionately; in like manner, all of the foregoing linear dimensions are also affected.

The operation of the invention is most quickly understood by following the passage of the air from the exterior side of the louver assembly, through the passageways and to the interior or outlet side of the louver assembly. It is generally agreed that free water, as rain, accompanying air entering the louver assembly in the direction of the arrows 59 must be prevented from passing to the interior or back side of the louver assembly. To accomplish this result, the various components of the louver assembly are each designed to help in removing a certain part of the free water, the combined effects being the elimination of water from the exiting air stream. The function of each component part will now be explained.

As the air stream enters the inlet passage 30, it is initially diverted 19 degrees by the canted inlet section 34 and, except for air-borne droplets, most of the rain or free water 63 in the air stream falls upon the surface 37 and drains freely away. Sporadic wind gusts can blow the accumulated water up the canted surface 37; however, due to the protruding extension 44, such water is effectively stopped and eventually drains back down the surface 37 and harmlessly falls to the outside. The initial air entry angle of 19.degree. is altered by the effect of the protruding extension 44. Thus, as the air stream travels toward the transition passage 31, its degree of ascent is gradually increased to approximately 30.degree.. Upon entering the transition passage 31, the air stream is subject to a second change in direction which varies from 46 degrees along the upper boundary of the air stream, to 51 degrees along the lower boundary of said air stream. It is during this direction change period that any air-borne droplets, not removed during passage through the inlet passage 30, are extracted by centrifugal forces resulting from the directional change of the air stream. As these droplets are thrown clear of the flowing air, they impinge upon the surface 41 of outlet section 35 of the adjacent louver 11. Due to the combined effect of natural gravity pulling and the air stream pushing, these droplets are propelled along the surface 41 until they enter the second protruding extension 48, where they are channeled in a horizontal direction to both ends of the blade 11. The accumulated water 63 is free to run off into the vertical gutters 18, 19 which channel the water downward to the canted surface 80 of channel member 26 and thus away from the louver assembly.

The advantage of the C-shaped passageway design and the circular ring sector shaped major extension 44 are manifested by the fact that air flowing through the multiple passages travels a relatively simple path with no restricted areas of less than the original width of the entry section, and that the major protruding section 44 is rounded, following an arc purposefully designed to maintain a passage width of not less than the original entry section width. Further, the transition passage 31 is smoothly and purposefully designed to reduce air friction. It has been found that the relatively moderate change in the air flow direction coupled with the extremely efficient water trapping characteristics of the two extensions 44, 48 extract water from the air stream without producing excessive and undesired turbulence with an accompanying air friction or pressure drop. Sufficient wind tunnel test data has been accumulated during the development of this design to indicate that it is capable of performing over a wide range of atmospheric conditions while fulfilling the foregoing objectives, as well as others.

A second preferred embodiment of the invention is illustrated in FIGS. 5 through 7 wherein the louver blades of the invention are disposed in a vertical orientation. As the louver blades of the second preferred embodiment are identical in structure to the louver blades of the first preferred embodiment, the same reference numerals are applied to the various components of the louver blades. Corresponding components of the frame assembly are prefaced by the number 1.

There is shown in FIG. 5 a louver assembly 109 of the invention functionally assembled in a ventilation opening provided in a wall 110 of a building. A plurality of louver blades 11 of the invention are assembled in a frame, indicated generally at 112. The louvers 11 are arranged in parallel spaced vertical relationship and are fixedly secured between horizontal outwardly open channel members 113, 114. Inner splicing elements 81, 115, 116 fit snugly within the channels of the respective channel members 113, 114 to reinforce the composite structure and facilitate the interconnection of additional louvers. A right vertical end casing 126 and a left vertical end casing 125, in conjunction with the upper and lower horizontal channel members 113, 114 form the structurally rigid enclosure or frame 112 for the louver blades 11. The right and left vertical end casings 126, 125 have outer surfaces 127, 84, respectively, which engage the confronting surfaces of the wall opening. The lower channel member 114 includes an exterior surface which extends horizontally across the louver assembly to constitute a lower sill plate 82. A back sill extension 124 is disposed in coplanar relation with lower channel member 114 and projects upward to form a rear water stop extending horizontally across the interior portion of the louver assembly.

As shown by FIG. 7, louvers 11 of the invention cooperate in pairs, as described in the first embodiment, adjacent louvers together defining a generally C-shaped passageway having an inlet 130, a transition passage 131 and an outlet passage 132. The structure and spaced relationship of the louvers 11 are the same as that of the first preferred embodiment, and therefore need not again be described. The illustrative dimensions offered in Table A are equally applicable to the second preferred embodiment of the invention wherein the louvers are disposed in a vertical orientation.

The orientation of the invention of the second embodiment differs only slightly from the operation of the first embodiment. As the air, indicated by arrows 159, flows through an inlet mouth 157, the majority of water droplets are deposited on the surface 37 of inlet section 34 of louver 11, and there is a natural tendency for the accumulated water to flow downward due to gravitational forces. Also, there is a natural tendency for part of this water to be blown rearward along the surface 37 of inlet section 34 where it is trapped by the major hook-like extension 44 and effectively drained downward to the sill. As the air flow exits the inlet passage 130, it must negotiate a change in direction of between 46 and 51 degrees as it passes through transition passage 131 to outlet passage 132. It is during this period that any air-borne droplets not removed upon passage through inlet pasage 130 are extracted by centrifugal force and deposited on the surface 41 of outlet section 35 of the adjacent louver. As the droplets are deposited, there is a natural tendency for accumulated water to flow downward due to gravitational force, as well as a natural tendency for part of this water to be blown rearward along surface 41 to the minor extension 48. The water is trapped by the minor extension 48 and drained downward to the sill without being permitted to again become air-borne. Water, indicated at 163, accumulating on this sill is kept from running into the interior or back side of the louver by means of the water stop 124 which acts as a dam. The water drains toward the front or entrance side of the louver and runs away from the louver.

As before, The C-shaped design of the passageway with the circular ring sector shaped major extension 44 provides the flowing air with a relatively simple path having no restricted areas less than the original width of the inlet mouth. Water is efficiently extracted from the air stream without producing excessive and undesired turbulence and accompanied air friction or pressure drop.

Claims

I claim:

1. A louver assembly for installation in a ventilation opening in a building including:

a frame defining a vertical plane;

a plurality of relatively spaced parallel elongated louvers supported by the frame within the plane of the frame;

said louvers having flat forward surfaces disposed at an acute angle relative to a line normal to the plane of the frame defining with adjacent louvers a series of angular inlet passages;

said louvers having rear surfaces connected to the forward surfaces disposed at an acute angle relative to a line normal to the plane of the frame and at an obtuse angle relative to the forward surfaces, defining with adjacent louvers a series of angular outlet passages;

first interior protruding extensions comprised as circular ring sectors disposed at the exterior angle of the intersection of each forward surface and rear surface to trap water in passing air, said circular ring sectors extending from the rear surfaces and having a portion extended along and spaced from the forward surfaces and forming with said forward surfaces an elongated open mouth facing the inlet passage;

each said inlet passage, circular ring sector, and outlet passage defining a generally C-shaped air passageway through the louver assembly;

second interior protruding extensions at the end of each rear surface disposed in the outlet passage on the louvers opposite the first protruding section, said second extensions extended along and spaced from the rear surfaces and forming with said rear surfaces an elongated open mouth facing the outlet passage, said second sections forming with adjacent rear surfaces an outlet for the passage; and

a lip extended across the front of each forward surface defining an inlet to the first inlet passage, said inlet having a width no greater than the width of any portion of the inlet passage and the outlet passage.

2. The louver assembly of claim 1 including: means securing said louvers in said frame in a generally horizontal orientation.

3. The louver assembly of claim 2 including: at least one first vertical gutter communicating with the second interior protruding extension of each louver at one end of the louver.

4. The louver assembly of claim 3 including: a second vertical gutter communicating with the second interior protruding extension of each louver at the end of the louver opposite to the first vertical gutter.

5. The louver assembly of claim 1 including: means securing said louvers in said frame in a generally vertical orientation.

6. The louver assembly of claim 1 wherein: said second interior protruding extensions are generally hook-shaped extensions facing the outlet passage.

7. The louver assembly of claim 1 wherein: the forward surfaces of the louvers are longer than the rear surfaces.

8. The louver assembly of claim 1 wherein: each first interior circular ring sector has a portion extended through a plane defined by the ends of the lips adjacent the inlets and the ends of the second interior protruding extension adjacent the outlet passage on the adjacent louver.

9. A louver assembly including:

a frame defining a vertical plane;

a plurality of relatively spaced parallel elongated louvers supported by the frame within the plane of the frame;

said louvers having flat forward surfaces disposed at an acute angle relative to a line normal to the plane of the frame defining with adjacent louvers a series of angular inlet passages;

said louvers having rear surfaces connected to the forward surfaces disposed at an acute angle relative to a line normal to the plane of the frame and at an obtuse angle relative to the forward surfaces, defining with adjacent louvers a series of angular outlet passages;

first interior protruding extensions comprised as circular ring sectors disposed at the exterior angle of the intersection of each forward surface and rear surface to trap water in passing air, said circular ring sectors extending from the rear surfaces and having a portion extended along and spaced from the forward surfaces and forming with said forward surfaces an elongated open mouth facing the inlet passage;

each said inlet passage, circular ring sector, and outlet passage defining a generally C-shaped air passageway through the louver assembly; and

second interior protruding extensions at the end of each rear surface disposed in the outlet passage on the louvers opposite the first protruding section, said second extensions extended along and spaced from the rear surfaces and forming with said rear surfaces an elongated open mouth facing the outlet passage, said second sections forming with adjacent rear surfaces an outlet for the outlet passage.

10. The louver assembly of claim 9 including: lip means extended along the front portion of the forward surface.

11. The louver assembly of claim 9 wherein: the first interior protruding extensions are circular ring sectors.

12. The louver assembly of claim 9 wherein: the forward surfaces of the louvers are longer than the rear surfaces.

13. The louver assembly of claim 10 wherein: each first interior extension has a portion extended through a plane defined by the ends of the lip means adjacent the inlet passages and the ends of the second interior protruding extension adjacent the outlet passage on the adjacent louver.