US3855371A

US3855371A - Humidifying apparatus for warm air ducts and the like

Info

Publication number: US3855371A
Application number: US00320818A
Authority: US
Inventors: W Morrow; G Anders
Original assignee: Aqua Mist Inc
Current assignee: Aqua Mist Inc
Priority date: 1973-01-03
Filing date: 1973-01-03
Publication date: 1974-12-17
Anticipated expiration: 1991-12-17

Abstract

An atomizing or spray type humidifier assembly to be removably mounted in an air conveying duct, such as a main trunk horizontal duct, of a hot air heating system. The humidifier assembly includes a solenoid controlled spray nozzle and a multi-layer screen supported in an elongated tunnel structure of rectangular cross-section having opposite open ends to be removably positioned wholly within the air conveying duct.

Description

1.1111100 States Patent 1191 Marrow et a1.

HUMIDIFYING APPARATUS FOR WARM AIR DUCTS AND THE LIKE Inventors: William B. Morrow, Winston-Salem; Gary H. Anders, Rural Hall, both of NC.

Aqua Mist, Incorporated, Winston-Salem, NC.

Filed: Jan. 3, 1973 Appl. No.: 320,818

Assignee:

us. (:1 261/100, 126/113, 261/116, 261/D1G. 15

1m. (:1 B0lf 3/04 Field 61 Search 261/98, 100, 105, 116, 261/126, DIG. 15, 94, 95, 91; 126/113 References Cited UNITED STATES PATENTS 2/1915 9/1930 ll/l966 Ohnemus Vreeland .1

Allcorn, Jr 261/91 X 14 1 Dec; 17, 1974 3,290,021 12/1966 Blachly et a1. -261/91 X 3,334,877 8/1967 Payne 26l/D1Gj 15 3,516,647 6/1970 Jaffe et a1. 1 261/100 X 3,570,472 3/1971 Santangelo 126/113 3,605,388 9/1971 Zuiderweg et a1. 261/126 X 3,689,037 /1972 Payne 26l/D1G. 15 3,770,254 11/1973 Morrow 261/D1G. 15

Primary Examiner-Tim R. Miles Assista nt ExaminerRichard L. Chiesa Attorney, Agent, or Firm-Mason, Fenwick & Lawrence 5 7 ABSTRACT An atomizing or spray type humidifier assembly to be removably mounted in an air conveying duct, such as a main trunk horizontal duct, of a hot air heating system. The humidifier assembly includes a solenoid controlled spray nozzle and a multi-layer screen supported in an elongated tunnel structure of rectangular cross-section having opposite open ends to be removably positioned wholly within the air conveying duct.

13 Claims, 6 Drawing Figures BACKGROUND AND OBJECTS OF THE INVENTION The present invention relates in general to humidifying apparatus for use in air conveying ducts, and more particularly to an atomizing or spray type humidifier assembly having a valve controlled spray nozzle and a multi-layer screen supported in a structure adapted to be removably mounted in an air conveying duct, such as the main trunk horizontal duct of a hot air heating system, for use in association with a forced circulation warm air heating furnace or the like. v

Heretofore, various means have been employed to supply water vapor to heated air in wann air heating systems, such as forced circulation warm air furnaces of the domestic type, to increase the relative humidity of the air being supplied through the duct system to the living space. One of the common humidifier arrangements for use in connection with warm air furnaces has beenthe provision of an open tray or receptacle located in the bonnet or riser of the warm air furnace to be supplied with water for free evaporation of the water into the warm air in the bonnet or riser. This type of humidifier is of limited and usually inadequate capacity, and becomes rapidly corroded or faulty and unreliable in operation. In some cases, rotating belts, wheels or drums of various types have been employed in the water-filled tray or receptacle to lift water droplets into more effective thermal exchange relation with the warm airin the bonnet. However, such moving belts, drums or screens require frequent cleaning and servicing, .due to deposits which rapidly form because of the water in thelocality and minerals or chemicals in the water, and provide another source of unreliable opera tion.

The furnace humidifier of the present invention is a simple unitary installation comprising an open ended tubular humidifier chamber fixed in selected angular relation to a planiform mounting plate so as to lie within the horizontal air conveying duct, such as the main trunk horizontal duct extending from a furnace, to define an air flow tunnel extending along the direction of air flow within the duct. A spray nozzle is disposed adjacent the open upstream end of the tunnel member to discharge towards the open downstream end of the tunnel member, and a plural layer wire mesh screen or similar foraminous member is supported in the tunnel member at its downstream open end in the path of the spray discharge from the nozzle to block the exit of water droplets from the tunnel member and to aid evaporation. The tunnel member is provided with means at the open upstream and downstream ends of the tunnel member to prevent loss of water droplets from the open ends and is provided with short lengths of drain tubing at locations to collect and lead off water which accumulates on the walls of the tunnel member to an external collecting facility. The tunnel member is fixed to the mounting plate at a selectedangular position and is simply installed by inserting the tunnel memher along a curved path through an opening 'cut in the heating system duct wall which is only slightly larger than the cross-sectional size of the tunnel member and v is covered by the mounting plate when the tunnel mem- Spray diffusing nozzle systems which discharge a mist or fog of water dropletsintothe bonnet or riser area have also been used, usually with a target plate, a collecting trough, or some other similar facility to collect unvaporized discharge from the nozzle. Many of these spray diffusing nozzle systems have been difficult to control in such a way as to reliably prevent unwanted discharge, such as drips,- from the nozzle following closber is inserted into the duct along a curved insertion path; The spray nozzle and solenoid control valve for the supply pipe to the spray nozzle are supported by the mounting plate in a proper preassembled position so that the inlet to the solenoid valve need merely be connected to an appropriate water supply.

An object of the present invention, therefore, is the provision of a novel atomizing typehumidifier device for use with air conveying ducts of a warm air heating system or the like which is simple in construction and easy to install by the average homeowner or purchaser, which is extremely flexible permitting it to be mounted in a number of different orientations, to dispose the tunnel portion thereof within the air conveying duct in ing of the supply valve regulating the water supply to the nozzle. When the valve is spaced some distance from the spray nozzle, there is a pressure head remaining between the control-valve and the nozzle when the valve closes. This pressure head'will cause the nozzle to spray and drip to some extent after the valve has closed. Such unwanted discharge or drips accumulate in the furnace in normal installations and produce corrosive precipitate solids which adversely affect the life or operation of the furnace. The spray humidifier systems have usually required complex special controls in addition to the usual controls for the furnace, and for the most part have been too complex to be suitable for installation by the ordinary, unskilled home owner as a do-it-yourself type of installation. If the spray humidifier system is to be readily adaptable to being installed by the average homeowner as a do-it-yourself installation, it is important that the humidifier unit involve only a few components to be installed on the furnace or ducting system and that it have provision for insuring that no water can be accidentally discharged in the bonnet or riser region.

a position for the air to flow through the tunnel member, and which is readily removable for replacement or cleaning of components which may be subject to contamination and provides highly reliable: humidity control for warm air furnaces of eitherthe electric, gas or oil type, heat pump systems, in a wide variety of types of furnace configurations and installation situations.

Other objects, advantages and capabilities of the present invention will become apparent from thefollowing detailed description, taken'in conjunction with the accompanying drawings illustrating a preferred em bodiment of the invention.

BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a front perspective view of the atomizing humidifier unit of the present invention;

FIG. 2 is a horizontal longitudinal section view, to en- FIG. 3 is a rear perspective view ofthe humidifier unit, viewed from the upstream end of the tunnel member;

FIG. 4 is a rear perspective view of the humidifierunit, viewed from the downstream end thereof;

FIG. 5 is a somewhat diagrammatic horizontal section view, illustrating positions of the tunnel member of the humidifier unit as the same is swung through an opening in the warm air duct wall into final position within the duct; and,

FIG. 6 is a somewhat diagrammatic vertical section view through a warm air duct, illustrating the position assumed by the humidifier when installed through the bottom of the duct.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawings, wherein like reference characters designate corresponding parts throughout the several figures, the atomizing type humidifier assembly of the present invention is indicated generally by the reference character 10 and comprises a rigid, substantially rectangular, planiform mounting plate 11 having an outer face or surface 12 and an inner surface 13. An elongated humidifier tunnel member or open ended chamber 14 is carried in inclined relation by the mounting plate 11 with one edge, specifically the upstream edge of one wall, of the tunnel member located against the inner surface 13. The tunnel member 14 is an elongated sheet metal member shaped to define a rectangular cross-section tunnel having an open downstream end 15 lying in a plane perpendicular to the longitudinal axis of the tunnel and an open upstream end 16 formed in a plane lying at an angle to the longitudinal axis of the tunnel.

The

sheet metal walls

14a, 14b, 14c and 14d defining the tunnel member 14 are provided with inturned lips or barrier flanges 17 at the end 15 and with inturned lips or barrier flanges 18 at the angular end 16 to define water barriers at the downstream and upstream ends of the tunnel to confine any water accumulating on the inner surfaces of the tunnel walls 14a-l4d to the interior of the tunnel. The tunnel wall 14a nearest the mounting plate 11 is secured, as by spot welding or similar fastening means, at its edge bounding the upstream opening 16 to the inner surface of the mounting plate 11 and the wall 14a and tunnel member 14 are maintained at a desired angle, for example about 5, relative to the plane of the mounting plate '11, by stand-off angle brackets or members 20 having one flange welded or suitably affixed to the mounting plate 11 against its inner surface 13 and the outer portions of the other flange weldedor suitably affixed to wall portions of the tunnel member, for example the

wall portions

14b and 14d.

Substantially centered just within the upstream end portion of the tunnel 14 along the center axis of the tunnel and directed downstream is a spray nozzle 22 mounted on a rigid right angle supply pipe, fonned for example from a short stub section 23, a 90 ell 24 and a length of rigid water supply pipe 25 extending through an accommodating aperture in the tunnel wall 14a and the mounting plate 11 to a solenoid valve 26. The inlet of the solenoid valve is connected by an convenient conventional tubing, indicated generally at 27, to a saddle valve or other means of connection to the house water line. A four layer wire screen is mounted within the tunnel member 14 immediately adjacent the downstream open end 15, and may be conveniently formed from a length of screen wire about 31 inches long by 6.5 inches wide, by forming eight transverse folds in the length of screen wire and folding the same to the configuration illustrated in detail in FIG. 2. In one preferred embodiment, the length of screen is folded along eight transverse folds indicated at 31a, 31b, 31c, 31d, 31e, 31f, 31g and 31h to produce four

square screen panels

32, 33, 34 and 35, each approximately 6.5 inches by 6.5 inches, with short end spacer flanges 36 and short intermediate connector flanges 37, the flanges 37 in one preferred example being one inch wide and the flanges 36 being /8 in. wide.

This humidifier unit is readily adaptable, by reason of its simplicity, and its flexibility as to orientation, to be installed by the average homeowner as a do-ityourself installation project. The installer merely cuts a rectangular or square opening 40, by following a template or dimensional directions which may be supplied with the humidifier kit, in an appropriate duct wall 41, either the horizontal bottom wall or one of the vertical side walls, of a horizontal warm air duct 42 such as the main trunk duct leading from the furnace indicated at 43 in FIG. 6. For one example of the humidifier unit, wherein the humidifier chamber or tunnel 14 defines a square cross-section of approximately 6% inches by 6% inches and the long side 14a is approximately 12 inches long, the opening 40 in the duct wall 41 may be about 7 inches by 7 inches. The humidifier unit may be readily mounted on the duct wall 41 by merely inserting the end portion 15 of the humidifier chamber or tunnel portion through the opening 40 to the position indicated in solid lines in FIG. 5, wherein the edge of the mounting plate 1 1 nearest the duct wall abuts or approximately abuts the duct wall 41. Then the humidifier unit is swung about an axis immediately adjacent or at the duct wall 41' through the successive positions indicated in broken lines in FIG. 5 to locate the humidifier chamber portion 41 within the duct with the inner surface 13 of the mounting plate 11 outwardly abutting the portions of the duct wall bounding the opening 40. Four sheet metal screws 44 are then inserted through corner openings in the mounting plate 11 and into the underlying duct wall portions to fix the humidifier unit in position.

It will be appreciated that the humidifier unit 10 can be mounted in either of three basic configurations. It may be installed through the bottom wall of the duct, indicated at 41a in FIG. 6, by cutting the insertion hole or opening 40 in the bottom horizontal wall 41a of the duct 42 and inserting the humidifier chamber or tunnel portion 14 upwardly through the opening 40 to assume the position illustrated in FIG. 6. The downstream end 15 of the humidifier chamber or tunnel portion 14 may either be extended to the right of the opening 40 if the air flow direction is toward the right as viewed in FIG. 6 and indicated by arrow 45, or it may be extended to the left of the opening 40 in case the air flow through the duct 42 is in the opposite direction. Alternatively, the insertion hole or opening 40 may be provided in either of the two vertical side walls 41b of the horizontal duct 42, with the humidifier chamber or tunnel portion 14 extending in a direction disposing the downstream end 15 either to the right of the opening 40 as viewed in FIG. 2, if the air flow is in the direction indicated by the arrow 46, or it may be located with the downstream end 15 extending to the left of the opening 40 in case the air flow is in the opposite direction from that indicated by the arrow 46 in FIG. 2.

Since the unit is provided with a pair of the short drain pipes 19 extending through the sheet metal wall 14a at both transverse ends of the acute angle corner llda at the upstream end of the tunnel formation, so that the two drain pipes 1-9 are disposed at the top and bottom of the tunnel formation when itis mounted in mation extends to the right of the insertion opening 40 as illustrated in FIG. 2 or whether it extends to the left of the insertion opening 40. Also the provision of the barrier flanges or

lips

17 and 18 at the downstream and upstream ends of the tunnel formation 14 extending inwardly from each of the four side walls forming the tunnel formation prevents any runoff at the upstream and downstream ends of the tunnel formation of any drippage from the nozzle 22 or excess water dropping to the bottom surface of the tunnel formation from the screen 30, and confines this water to the humidifier chamber or tunnel zone so that the water ultimately is carried away by one of the drains 19. When the tunnel .formation 14 is mounted in the position illustrated in FIG. 6 wherein the mounting plate is secured to the bottom horizontal wall 41a of the duct, the inclined position of the lower wall 14a causes the water which drops onto the wall 14a, which is now the bottom wall of the tunnel, to flow by gravity downwardly to the corner 16a and out either of the drain pipes 119. The inclination of the wall 14a relative to the plane of the mounting plate 11 also enables the humidifier to be inserted in the duct and shifted to the positions illustrated in FIG. 5 through an opening which is only slightly I larger than the cross-section of the tunnel formation .and can .be readily covered by'the mounting plate 11.

The inlet conduit 27 to the solenoid valve 26 is readily connectable to a conventional house water line, as by providing a plastic tube extending from the inlet of valve 26 or. from a short stub pipe extending from that inlet, with the other end of the tube connected by a saddle valve or other conventional means to an existing house water line.

The electrical power for the solenoid valve .is typically derived from the furnace blower motor so that the solenoid valve 26 is opened only when the furnace blower is operating. The solenoid valve can be connected directly to a 120 volt circuit for the blower motor, or may be connected through a step-down transformer to the blower motor so that the voltage supplied to the solenoid valve coil is only 24 volts,- at the option serves to block the exit of water droplets from the humidifier and into the furnace duct. At the same time,

air passing through the screen 30 will evaporate some I of the water held on the screen itself. Water in excess of that which is evaporated drops to the bottom surface of the humidifier chamber or tunnel portion 14 and is carried away by the drain 19. The installation may be readily made by the home owner, and the unit may be readily removed from the duct and serviced, whenever required, without the need of skilled labor.

What is claimed is:

1. A humidifier assembly for use in association with a forced circulation warmair heating system including a horizontal heated air supply duct section communicating with a furnace and having a flat duct wall portion having an insertion opening formed therein, the humidv ifier assembly comprising a' rigid planar mounting plate of a size to cover said insertion opening having edge portions to overlie the duct wall' portions bounding said opening and be fastened thereto, an elongated tunnel duct member of .four fiat solid sheet metal tunnel walls of greater length than the dimension of the insertion of the installer. Also, if desired, a humidistat control of conventional construction may be insertedin electrical series with the solenoid valve so that the humidifier will only spray when the furnace blower is operating and the ambient humidity is below the humidistat setting, or is operated when the furnace blower is operating and the humidistat is set to the ON position if the humidistat has such a setting.

With the installation wired either directly to the fur nace blower motor or in series with a humidistat control to the fumace blower motor, the solenoid valve 26 is opened to supply water to the atomizing nozzle 22 whenever the furnace operates (and when humidity is called for if a humidistat is included in the circuit). The

opening along the direction of air flow in the duct section joined together along their-longitudinal edges and defining an elongated humidifier tunnel of rectangular cross-section extending along a rectilinear tunnel axis inclined at a sharp angle to the plane of said mounting plate and having opposite open ends forming upstream and downstream end portions of the tunnel, means fixing said duct member to said mountingplate to locate the tunnel wholly within the duct section with a wall of the duct member supported against the mounting plate for flow of heated duct air there'through with the downstream end portion located downstream beyond said opening when the mounting plate is positioned in covering relation to the opening, a spray discharge nozzle coupled through a valve to a water source and located within the tunnel adjacent its upstream end for discharging a mistlike spray pattern of water droplets in a downstream direction within the tunnel, and an evaporation screen supported within said tunnel downstream of said nozzle in the path of saidwater droplets to collect droplets thereon and evaporate them into the air flowing through the tunnel.

2. A humidifier assembly as defined in claim 1,

wherein said tunnel walls have barrier flanges at the up-. stream and downstream edges thereof extending toward the center axis of the tunnel to retain within the tunnel any drippagefrom the nozzle or excess water runoff from'the screen.

3. A humidifier assembly as defined in claim 2, including drain pipe means extending through a selected wall of the tunnel and outwardly through said mounting plate to communicate with the region within the tunnel where water dripping from the nozzle or'screen may collect to drain such water to the exterior of the duct.

4. A humidifier assembly as defined in claim 2,

wherein the tunnel wall adjacent the mounting plate is joined thereto at the upstream edge of the tunnel wall, the upstream edges of said tunnel walls lying in a plane inclining inwardly of the ductsection from the mounting plate in a downstream direction at an angle of subthrough the mounting plate into the tunnel at the juncture of said mounting plate and upstream edge of the adjacent tunnel walls to withdraw water accumulations from within the tunnel.

5. A humidifier assembly as defined in claim 4, wherein said drain pipe means comprises a pair of drain pipes located at the opposite transverse limits of the upstream edge of said selected wall to dispose said drain pipes immediately inwardly adjacent the top and bottom walls respectively of the tunnel when the mounting plate is mounted against a vertical side wall of the duct.

6. A humidifier assembly as defined in claim 2, wherein said screen is a wire mesh screen having a plurality of rectangular, parallel substantially planar screen panels and each vertically and horizontally spanning the tunnel in planes perpendicular to the tunnel axis adjacent the downstream end of the tunnel.

7. A humidifier assembly as defined in claim 1, including drain pipe means extending through a selected wall of the tunnel and outwardly through said mounting plate to communicate with the region within the tunnel where water dripping from the nozzle or screen may collect to drain such water to the exterior of the duct.

8. A humidifier assembly as defined in claim 7, wherein said drain pipe means comprises a pair of drain pipes located at the opposite transverse limits of the up- 9. A humidifier assembly as defined in claim 1, wherein the tunnel wall adjacent the mounting plate is joined thereto at the upstream edge of the tunnel wall,

the upstream edges of said tunnel walls lying in a plane inclining inwardly of the duct section from the mounting plate in a downstream direction at an angle of substantially less than ninety degrees to the mounting plate plane to define an air inlet opening to the tunnel at its upstream end of larger area than the cross sectional area of the tunnel.

10. A humidifier assembly as defined in claim 9, wherein said screen is a wire mesh screen having a plurality of rectangular, parallel substantially planar screen panels folded from a single length of screen and each vertically and horizontally spanning the tunnel in planes perpendicular to the tunnel axis adjacent the downstream end of the tunnel.

11. A humidifier assembly as defined in claim 9, wherein said drain pipe means comprises a pair of drain pipes located at the opposite transverse limits of the upstream edge of said selected wall to dispose said drain pipes immediately inwardly adjacent the top and bottom walls respectively of the tunnel when the mounting plate is mounted against a vertical side wall of the duct.

12. A humidifier assembly as defined in claim 11, wherein said screen is a wire mesh screen having a plurality of rectangular, parallel substantially planar screen panels folded from a single length of screen and each vertically and horizontally spanning the tunnel in planes perpendicular to the tunnel axis adjacent the downstream end of the tunnel.

13. A humidifier assembly as defined in claim 1, wherein said screen is a wire mesh screen having a plurality of rectangular, parallel substantially planar screen panels and each vertically and horizontally spanning the tunnel in planes perpendicular to the tunnel axis adjacent thedownstream end of the tunnel.

Claims

1. A humidifier assembly for use in association with a forced circulation warm air heating system including a horizontal heated air supply duct section communicating with a furnace and having a flat duct wall portion having an insertion opening formed therein, the humidifier assembly comprising a rigid planar mounting plate of a size to cover said insertion opening having edge portions to overlie the duct wall portions bounding said opening and be fastened thereto, an elongated tunnel duct member of four flat solid sheet metal tunnel walls of greater length than the dimension of the insertion opening along the direction of air flow in the duct section joined toGether along their longitudinal edges and defining an elongated humidifier tunnel of rectangular cross-section extending along a rectilinear tunnel axis inclined at a sharp angle to the plane of said mounting plate and having opposite open ends forming upstream and downstream end portions of the tunnel, means fixing said duct member to said mounting plate to locate the tunnel wholly within the duct section with a wall of the duct member supported against the mounting plate for flow of heated duct air therethrough with the downstream end portion located downstream beyond said opening when the mounting plate is positioned in covering relation to the opening, a spray discharge nozzle coupled through a valve to a water source and located within the tunnel adjacent its upstream end for discharging a mistlike spray pattern of water droplets in a downstream direction within the tunnel, and an evaporation screen supported within said tunnel downstream of said nozzle in the path of said water droplets to collect droplets thereon and evaporate them into the air flowing through the tunnel.

2. A humidifier assembly as defined in claim 1, wherein said tunnel walls have barrier flanges at the upstream and downstream edges thereof extending toward the center axis of the tunnel to retain within the tunnel any drippage from the nozzle or excess water runoff from the screen.

3. A humidifier assembly as defined in claim 2, including drain pipe means extending through a selected wall of the tunnel and outwardly through said mounting plate to communicate with the region within the tunnel where water dripping from the nozzle or screen may collect to drain such water to the exterior of the duct.

4. A humidifier assembly as defined in claim 2, wherein the tunnel wall adjacent the mounting plate is joined thereto at the upstream edge of the tunnel wall, the upstream edges of said tunnel walls lying in a plane inclining inwardly of the duct section from the mounting plate in a downstream direction at an angle of substantially less than 90* to the mounting plate plane to define an air inlet opening to the tunnel at its upstream end of larger area than the cross sectional area of the tunnel, and exterior drain pipe means extending through the mounting plate into the tunnel at the juncture of said mounting plate and upstream edge of the adjacent tunnel walls to withdraw water accumulations from within the tunnel.

7. A humidifier assembly as defined in claim l, including drain pipe means extending through a selected wall of the tunnel and outwardly through said mounting plate to communicate with the region within the tunnel where water dripping from the nozzle or screen may collect to drain such water to the exterior of the duct.

8. A humidifier assembly as defined in claim 7, wherein said drain pipe means comprises a pair of drain pipes located at the opposite transverse limits of the upstream edge of said selected wall to dispose said drain pipes immediately inwardly adjacent the top and bottom walls respectively of the tunnel when the mounting plate is mounted against a vertical side wall of the duct.

9. A humidifier assembly as defined in claim 1, wherein the tunnel wall adjacent the mounting plate is joined thereto at the upstream edge of the tunnel wall, the upstream edges of said tuNnel walls lying in a plane inclining inwardly of the duct section from the mounting plate in a downstream direction at an angle of substantially less than ninety degrees to the mounting plate plane to define an air inlet opening to the tunnel at its upstream end of larger area than the cross sectional area of the tunnel.

13. A humidifier assembly as defined in claim 1, wherein said screen is a wire mesh screen having a plurality of rectangular, parallel substantially planar screen panels and each vertically and horizontally spanning the tunnel in planes perpendicular to the tunnel axis adjacent the downstream end of the tunnel.