Humidifier

Abstract

A humidifier for use in a warm-air heating system is disclosed. In one embodiment the humidifier includes a bleedoff drain for removing heavy mineral deposits resulting from hard water. A double-acting float valve which is responsive to the action of an airflow vane controls inlet water. The case of the humidifier has interchangeable panels so that the inlet duct can be installed on either side without necessitating any modifications. The rotating evaporator drum has removable end caps for ease in cleaning or replacing the evaporator pad enclosed therewithin.

Description

This invention generally relates to humidifiers, and more particularly relates to humidifiers of the type adapted to be inserted between a forced-air heating system and the ducts thereof.

Modern heating systems for homes and other buildings include several basic types of units. These units are classified either by the type of fuel used or by the type of heat distribution system used. Included in the latter category are steam heating, hot-water heating, and forced-air heating systems. With the advent of cheap natural fuels and efficient burning systems forced-air heating systems have become extremely popular. The heat can be more readily distributed and unsightly heat exchanging units are eliminated. Further, since the burner itself is more efficient, there is a remarkable lack of dust and soot produced. In addition, forced-air heating systems lend themselves to combination with central air conditioning since only one set of ducts and outlets need be provided. Another obvious advantage of forced-air heating systems is the lack of extensive plumbing connections which need regular maintenance.

An important and noteworthy drawback in forced-air heating systems resides in the fact that the air in the enclosed area which is being heated is usually low in moisture content. A basic relationship exists between the temperature of the air and the moisture contained by the same. Relative humidity can be defined as the amount of moisture in the air as compared with the amount that the air could contain at the same temperature expressed as a percentage. It, therefore, follows that if cool air, which is capable of containing only a fairly low amount of moisture, at a high relative humidity, is heated, the amount of moisture in the air remains exactly the same while the amount of moisture the air could contain rises. The result of this is an extremely low relative humidity. While unusually high relative humidity causes a great deal of discomfort, it is generally acknowledged that unusually low relative humidity can be equally as uncomfortable and can cause damage to both animate and inanimate objects. If the air is too dry, wooded objects tend to dry out and contract with consequent damage thereto. Such wooden objects could include furniture as well as structural members of a building. As for the effects on the occupants of a building, various sinus tissues become dry and irritated. Further, static electricity easily builds up and creates extremely uncomfortable conditions.

These various ill effects associated with heating systems can be eliminated by providing a humidifier in the air handling system to raise the relative humidity of the air before passing it to the enclosed area which will be heated. Basically, such humidifying systems have a water reservoir, connected to a source of supply, a mechanism for increasing the contact area of the air with the water and air inlet and outlet connections. This basic system, however, suffers several disadvantages. The first of the disadvantages concerns the water delivery system to the humidifier. A reservoir of water, without some automatic delivery system, would soon run dry. Accordingly, means to provide a constant source of water must be included in the unit. With such means must be associated means for controlling the delivery of water to the unit. Various such delivery means have been used, but not all of them are able to compensate for fluctuations in evaporation rate due to air velocity and/or ambient relative humidity.

Also, depending on the hardness of the water in a particular area, a buildup of minerals in the reservoir can occur, thereby necessitating frequent cleaning and perhaps even repairs. Associated with the necessity to compensate for water hardness is the necessity to control the growth of algae in the reservoir. It is, therefore, a primary object of the present invention to provide a humidifier which has a water control mechanism responsive to airflow as well as to water hardness.

It is another object of the present invention to provide a humidifier which maintains a constant level of water in its reservoir while bleeding-off mineral-rich water therefrom.

A second disadvantage associated with the humidifiers of the prior art concerns the means for providing a large air-water contact area. Such means are often expensive and require frequent replacement due to clogging and other lessening of efficiency. Further, such means are often extremely inaccessible, thereby requiring the presence of professional servicemen to perform that operation. It is, therefore, another primary object of the present invention to provide means for increasing the contact area between the air and the water which can be easily serviced and/or replaced.

It is still another object of the present invention to provide such means which is both accessible and reusable.

Consistent with the foregoing objects, it is another object of the present invention to provide a humidifier with a case that can be easily opened for convenient access to the interior thereof for either servicing the air-water contacting means or cleaning the reservoir.

A third disadvantage of the prior art humidifiers is concerned with the installation of the same more than with its operation. Most such humidifiers have a fixed air inlet connection and a fixed air outlet connection which dictates the position and installation of the unit. It has been found that such factors as space, duct construction, available plumbing connections, and available wiring connections, affect the ultimate installation of the humidifier. If the humidifier is constructed in such a way that it can only be installed in one position and in one manner, one or more of these factors must be manipulated by the installer to conform to the humidifier.

A need, therefore, exists for a humidifier which can be installed in conformance with existing architectural conditions with the air inlet and outlet connections conforming thereto. To this end it is another primary object of the present invention to provide a humidifier which can be easily installed without any modification either to the connections thereon or to other external factors. More specifically, it is an object of the present invention to provide a humidifier with a case constructed such that the air inlet connection can be attached to either side thereof without any special tools or facilities.

Consistent with the foregoing objects, the present invention provides a humidifier which bleeds off water in an overflow manner. A float control regulates the amount and rate of water entering the unit. As fresh water enters the unit the mineral-rich water is drawn off through the overflow. Controls are provided to adjust the float travel according to the hardness of the water, and to regulate the waterflow responsive to the airflow. A rotating drum with an evaporator pad therein provides the necessary contact area between the flowing air and the water. In order to gain access to the interior of the humidifier, a quick release mechanism is provided to remove the pan after which the drum can be easily removed. The drum comprises a wire cage which clips on to two retainer ends. When the retainer ends are removed the pad can simply slide out of the cage for cleaning. The case is constructed such that either side thereof can be used for the air inlet fitting. One side of the case is secured to an adapter plate for the air inlet fitting and an inspection panel is secured to the other side.

The invention will be better understood, and objects other than those specifically set forth above will become apparent, after reading the following detailed description.

Such description makes reference to preferred and illustrative features of the invention presented in the annexed drawings, wherein:

FIG. 1 is a side-elevational view, partially broken away, of the humidifier of the present invention;

FIG. 2 is an exploded perspective view of the rotating drum;

FIG. 3 is an enlarged fragmentary cross-sectional view of the drum-securing means;

FIG. 4 is a perspective view of the humidifier of the present invention, partially in phantom to illustrate the water controls; and

FIG. 5 is a partially fragmentary, partially exploded, perspective view of the humidifier of the present invention.

Turning now to the drawings, the humidifier generally designated by the numeral 10 in FIG. 1, has a casing 12 which comprises a pan 14 and a cover member 16. Water is supplied through inlet 18 to the pan. An overflow drain 20 is provided as a safety feature an drain plug 22 is provided for use whenever necessary for cleaning out the pan or servicing the unit. Bleedoff drain 24 is used to remove the mineral-rich water which might accumulate. Air to be humidified enters through the inlet (not shown) where it contacts the rotating evaporator drum 26 and then leaves through the outlet 28 activating vane 30.

Attention is now drawn to FIG. 4 wherein the pan 14, the cover member 16, the drum 26 and the outlet 28 are shown in phantom. Water entering through inlet 18 passes through float valve 30 before entering the pan 14. Float valve 30 is controlled by float 32 responsive to the water level in the pan 14. The water level in pan 14 is determined by the setting of float-adjusting screw 34. When float-adjusting screw 34 is turned, the head thereof being accessible outside of the case, it moves worm shoe 33 which is connected to float arm 35, thereby setting the level of float 32. Float 32 is also connected to float valve 30 by means of float arm 35 and worm shoe 33. Bleedoff drain-adjusting screw 42 is then adjusted so that float pressure arm 40 just touches float 32. This, also, is accomplished from outside the case. Bleedoff control knob 36 rotates cam 38 which limits the downward travel of float pressure arm 40, thereby affecting float 32. Bleedoff control knob 36 is set according to the relative hardness of the water, rotating through 90.degree. from an "off" position which is used in an area of algae-free soft water to a "maximum" position for water of 30 or more grains per gallon hardness. The bleedoff control has a dual action and is actuated by vane 43. Air entering inlet 44 contacts the rotating drum 26 and exits through outlet 28 thereby activating vane 43 which is connected to, and depresses, float pressure arm 40 by linkage 46. Linkage 46 is supported by brackets 47 which are anchored in cover member 16. It can, therefore, be seen that in operation the float 32 will be depressed either by a lowered water level due to evaporation or by action of the vane 43, thereby allowing water to enter through inlet 18 and float valve 30 to maintain the proper level in pan 14. As water evaporates, however, it leaves a high concentration of minerals in pan 14. When fresh water is introduced through float valve 30 the water which has a high concentration of minerals will flow out through bleedoff drain 24. Bleedoff drain-adjusting screw 42 is also used to compensate for differences in water pressure when installing and adjusting the unit. Further, if for any reason a constant flow of water is desired, this can be accomplished by adjusting screw 42 sufficiently to depress float 32. Thus it can be seen that bleedoff drain-adjusting screw 42 regulates the water level and, therefore, the flow through bleedoff drain 24.

Evaporator drum 26, as shown in FIG. 2, comprises wire cage 48, closed end 50, open end 52 and evaporator pad 54. Evaporator pad 54 is made of any suitable known material which can be immersed in water thereby absorbing the same, and which will release the water to a stream of warm air coming in contact therewith. Evaporator pad 54 is enclosed in wire cage 48 and endpieces 50 and 52 clipped thereon to secure the pad 54 in place. The clip members 56 on endpieces 50 and 52 securely grip the loops 58 of wire cage 48. The method of attaching or detaching endpieces 50 and 52 from wire cage 48 is shown in FIG. 3. Clip 56 securely holds loop 58 by the natural spring action of the wire from which the cage 48 is made. In order to remove endpieces 50 and 52, loop 58 is depressed to the position shown at 60 in phantom, thereby disengaging clip 56. Open end 52 has a shaft 62 which is supported on a suitable bearing surface. Closed end 50 is engaged by a shaft in motor 64 (FIG. 1) which rotates drum 26 responsive to the action of a humidistat (not shown) when the blower of a heating unit is in operation. The motor 64 is shown in FIG. 5 with the cover plate 66 removed.

To remove the drum 26, the pan is removed in a manner described hereinbelow. The open end 52 is disengaged from its supporting loop or bearing and the drum is partially lowered at that end. The closed or driven end 50 is then slid off the motor shaft and the drum is removed by dropping the same downwardly.

The unit 10 is made such that it can be mounted with the air inlet 44 on either side without the use of tools, and to this end the case, comprising pan 14 and cover member 16, is provided with two similar openings, one on each side. This flexibility of mounting, of course means that the unit can be turned end for end when installing without the necessity for any modification. The sequence of steps for mounting, or installing, the unit will be described with reference to FIG. 5. The mounting plate 78 is mounted on the warm-air plenum by any suitable means such as sheet metal screws 80 and nuts or clips 82. Cover member 16 is then hooked over upper tangs 84. Hooks 68 at the outlet end of pan 14 are engaged with brackets 70 on cover member 16 and the other end of pan 14 is raised so that pan 14 engages lower tang 86 and upper flange 72 and lower flange 74 meet. Slide 76 then engages flanges 72 and 74 to lock the case members together. To disassemble the case, the procedure is simply reversed. The inspection plate 88 is mounted on the other side with spring clips 90.

It should be noted that while the preferred mode of operation requires that the unit be mounted on the warm side discharge air plenum with a bypass connected to the suction, or return air, side, a reversed mounting procedure can be used when space or other considerations so dictate. In that case, it is understood that the terminology used herein to denote the inlet and outlet would also be reversed. The external wiring and plumbing connections are conventional.

Thus it will now be seen that there is herein provided means which satisfy all of the objects of the instant invention, and others, including many advantages of great practical utility and commercial importance.

Claims

What I claim is:

1. In a humidifier having a case, rotating evaporative drum means, an air inlet and an air outlet, a water reservoir pan, water inlet means, water bleedoff means, float valve means connected to said water inlet means to regulate the inflow of water, float means operatively connected to said float valve means, float pressure arm means in contact with said float to control the water level, external bleedoff control knob means regulating said float pressure arm means, vane means located in said air outlet and connected to said pressure arm means by linkage means, whereby said float means is depressed by either actuation of said vane means or by a lowering of the water level within said pan.

2. A humidifier as defined in claim 1, wherein said external bleedoff control knob means limits said float pressure arm means by cam means.

3. A humidifier as defined in claim 1, wherein said rotating evaporative drum means comprises a wire cage means defining a generally cylindrical form and having end loops, an evaporator pad held within said cage means, and end members which manually clip on said end loops.

4. A humidifier as defined in claim 1, wherein said case comprises an upper member and a lower member, said lower member being said pan, said upper member having a pair of brackets at the outlet end thereof to engage a pair of cooperating hooks on said lower member, both said upper member and said lower member having flanges at the end opposite the outlet end thereof, and a retainer slide to engage said flanges, thereby locking said lower member to said upper member.

5. A humidifier as defined in claim 1, wherein said case includes an opening on each side thereof, said openings being substantially identical, one of said openings being secured to a mounting plate for said air inlet, and an inspection plate secured over the other opening.

6. A humidifier as defined in claim 1, wherein said float means is connected to said float valve means by a float arm and a worm shoe, said worm shoe being engaged with a worm screw which is adjustable externally of said case.

7. In a humidifier having a case, an air inlet and an air outlet, a water reservoir pan, water inlet means, water inlet regulatory means, and rotating evaporative drum means, said drum means comprising a wire cage defining a generally cylindrical form and having end loops, an evaporator pad held within said cage means, and end members which manually clip on said end loops.