Evaporator apparatus

An evaporator including a housing defining an air inlet, an air outlet, and a reservoir for a liquid supply; a blower for producing air flow in a path between the inlet and the outlet; a vessel retained by the housing above the reservoir and adapted to retain a liquid volume; a wick means retained by the vessel and comprising a source portion submerged in the liquid volume and an evaporative portion disposed in the air flow path, the wick means adapted to provide by capillary action liquid flow from the source portion to the evaporative portion; and a pump means for pumping liquid from the reservoir to the vessel so as to maintain the liquid volume therein. The output capacity of the evaporator is increased by pumping liquid from a reservoir upwardly to a supply vessel.

BACKGROUND OF THE INVENTION 
This invention relates generally to an evaporator device and, more 
particularly, to an evaporator device utilizing liquid absorbing wick 
elements to provide humidification. 
Evaporator devices are used extensively to enhance personal comfort by 
increasing the level of humidity in an enclosed environment. They can 
function additionally to provide cooling in many hot, dry regions. One 
well known type of evaporative humidifier employs absorbing wick elements 
that produce by capillary action liquid flow from a reservoir to wick 
portions disposed in a path of airflow provided by an electrical blower. 
One deficiency of wick type evaporators results from the inability of wick 
elements to draw liquid beyond a maximum height of about six inches. 
Because of this factor, the effective airflow output of wick type 
evaporators in cubic feet per minute (CFM) has been limited. 
The object of this invention, therefore, is to provide an improved wick 
type evaporative humidifier exhibiting an increased airflow output. 
SUMMARY OF THE INVENTION 
The invention is an evaporator including a housing defining an air inlet, 
an air outlet, and a reservoir for a liquid supply; a blower for producing 
air flow in a path between the inlet and the outlet; a vessel retained by 
the housing above the reservoir and adapted to retain a liquid volume; a 
wick means retained by the vessel and comprising a source portion 
submerged in the liquid volume and an evaporative portion disposed in the 
air flow path, the wick means adapted to provide by capillary action 
liquid flow from the source portion to the evaporative portion; and a pump 
means for pumping liquid from the reservoir to the vessel so as to 
maintain the liquid volume therein. The output capacity of the evaporator 
is increased by pumping liquid from a reservoir upwardly to a supply 
vessel. 
According to specific features of the invention, the vessel comprises a 
lower vessel retained by the housing above the reservoir and adapted to 
retain a given portion of the liquid volume, and an upper vessel retained 
by the housing above the lower vessel and adapted to retain a 
predetermined portion of the liquid volume; and the wick means comprises a 
lower wick comprising a lower source portion submerged in the given 
portion and a lower evaporative portion disposed in the air flow path, and 
an upper wick comprising an upper source portion submerged in the 
predetermined portion and an upper evaporative portion disposed in the air 
flow path. Evaporative capacity is further enhanced by the provision of 
upper and lower vessels and wicks. 
According to other features of the invention, the pump means comprises a 
feed tube for circulating liquid from the reservoir to the upper vessel, 
the upper vessel defines an upper overflow for discharging by gravity 
liquid into the lower vessel so as to maintain the predetermined portion 
in the upper vessel, and the lower vessel defines a lower overflow for 
discharging liquid by gravity into the reservoir so as to maintain the 
given portion in the lower vessel. This structural arrangement simplifies 
the feed of liquid to the upper and lower vessels. 
According to still other features of the invention, the housing comprises 
an outlet sidewall having outlet openings defining the outlet, the outlet 
sidewall is adapted for pivotal movement between open and closed 
positions, and the upper and lower vessels are supported by the outlet 
sidewall for pivotal movement therewith. The pivotal sidewall facilitates 
access to the wick elements retained by the upper and lower vessels. 
According to a further feature of the invention, the outlet sidewall, the 
upper vessel and the lower vessel are removable as a unit from the 
housing. This structural arrangement simplifies servicing of the wick 
elements. 
According to yet another feature of the invention, the housing further 
defines a tray disposed above the upper vessel, a drain providing liquid 
communication between the tray and the upper evaporative portion of the 
upper wick, and a top wall movable into an open position to provide access 
to the tray. The cooling effect of the evaporator is enhanced by 
depositing in the tray ice that melts and feeds cold water to the upper 
evaporative portion. 
According to additional features, the housing further defines a removable 
container defining the reservoir and a sidewall door providing access 
thereto, and the invention includes a removable tank accessible through 
the sidewall door and adapted for filling with liquid, and a valve for 
discharging liquid retained by the tank into the container. The removable 
container simplifies cleaning thereof and the removable tank simplifies 
filling of the container reservoir. 
According to further features of the invention, the valve is a check valve 
having an actuator stem, the tank comprises a bottom wall retaining the 
check valve with the actuator stem projecting outwardly therefrom, and the 
container further defines support means shaped and arranged to support the 
tank in an inclined position with the bottom wall facing downwardly and an 
actuator surface disposed to engage the actuator stem and induce discharge 
of liquid retained by the tank. These structural features facilitate and 
insure automatic discharge of liquid from the tank into the reservoir 
container. 
According to important features of the invention, the pump means comprises 
a pump pivotally supported in the container by the housing and pivotable 
into a position out of the container so as to permit removal thereof 
through the sidewall door, a switch functional to either energize or 
deenergize the pump, and a float operatively coupled to the switch and 
pivotable with the pump, the float is operable to cause energization of 
the pump in response to a given minimum liquid level in the reservoir and 
to cause deenergization of the pump in response to either a level of 
liquid in the reservoir less than the given level or pivotal movement of 
the pump out of the container. These features insure proper and safe 
operation of the pump and permit removal of the container from the 
housing. 
According to other features of the invention, the bottom wall of the tank 
defines a recess accommodating the pump, and an end of the tank opposite 
to the bottom wall defines a handle. The recess permits a compact 
arrangement of components and the handle facilitates handling of the 
removable tank.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
An evaporator 11 includes a housing 12 having sidewalls 13, 14, a front 
sidewall 5, a rear sidewall 16 and a top wall 17. Supporting the housing 
12 are a plurality of rollers 18. A power cord 19 for connection in a 
suitable household outlet (not shown) extends out of the rear sidewall 16. 
Included in the front sidewall 15 is an upper inlet portion 21 defining a 
plurality of inlet openings 22. Also included in the front sidewall 15 is 
a door 23. The rear sidewall 16 includes an outlet portion 25 that defines 
a plurality of outlet openings 26. 
As shown in FIGS. 4 and 5, the outlet portion 25 of the rear sidewall 16 
supports in a vertically stacked arrangement an upper trough vessel 31 and 
a lower trough vessel 32. Retained by the upper trough 31 is an upper wick 
cartridge 34 having a source portion 35 disposed in the trough 31 and an 
evaporative portion 36 projecting upwardly therefrom. Similarly, the lower 
trough 32 retains a lower wick cartridge 38 having a source portion 39 
within the trough 32 and an evaporative portion 41 projecting upwardly 
therefrom. A blower fan 43 is supported within the housing 12 between the 
inlet 21 and the outlet 25. Rotatably coupled to the fan 43 is an 
electrical motor 44 connected to a conventional electrical control section 
45 retained in an upper front portion of the housing 12. When energized, 
the motor 44 produces rotation of the fan 43 to produce airflow between 
inlet 21 and the outlet 25 in a path that includes the upper evaporative 
portion 36 of the upper wick cartridge 34 and the lower evaporative 
portion 41 of the lower wick cartridge 38. Also retained in the upper 
portion of the housing 12 behind the electrical control section 45 is an 
open tray 47 that is disposed above the upper wick cartridge 34. Covering 
the tray 47 is a lid portion 48 of the top wall 17. The lid 48 can be 
opened as shown in FIG. 4 to provide access to the tray 47. 
Retained in a lower portion of the housing 12 below the lower trough 32 is 
a removable container 51 that defines a reservoir 52 for a supply of 
liquid such as water. Formed on opposite sidewalls of the container 51 are 
aligned support shoulders 53, 54 that slope downwardly toward a rear wall 
56. A vertical ridge 57 projects inwardly from the rear wall 56 and 
defines an actuator surface 58. Removably supported on the support 
shoulders 53, 54 is a tank 61 that slopes downwardly therewith. As shown 
most clearly in FIG. 6, the tank 61 has a bottom wall 62 that defines a 
valve recess 63 and a pump recess 64. Formed in the bottom wall 62 within 
the valve recess 63 is an externally threaded spout 66 that can be used to 
fill the tank 61 with liquid. A cap 67 for the spout 66 retains a 
conventional check valve 68 having an outwardly projecting actuator stem 
69. With the tank 61 in a fully inserted position on the container 51 as 
shown in FIG. 4, the vertical ridge 57 on the rear wall 56 is accommodated 
by the valve recess 63 and the actuator stem 69 forcibly engages the 
actuator surface 58. A handle 71 extends between outer sidewall portions 
of the tank 61. Access to the removable container 51 and the removable 
tank 61 is provided with the door 23 in an open position as shown in FIG. 
4. 
A pump assembly 73 is retained in the lower portion of the housing 12 below 
the upper and lower troughs 31, 32. Pivotably supporting the pump assembly 
73 from the rear wall 16 of the housing 12 is a pivot pin 75. The pump 
assembly 73 includes a liquid pump 76 disposed near the bottom of the 
container 51 and a conventional float mechanism 77 adapted to move 
upwardly and downwardly in response to changes in the level of the liquid 
within the reservoir 52. Operably coupled to the float mechanism 77 is an 
electrical on/off switch 78 connected between the electrical motor 44 and 
the electrical control section 45. The pump assembly 73 is accommodated by 
the pump recess 64 in the tank 61. 
As shown in FIG. 5, a first feed tube 81 has one end attached to an outlet 
of the pump 76 and an opposite end opening into a collection vessel 82 in 
the upper portion of the housing 12 adjacent to the tray 47. Liquid fed 
into the collection vessel 82 drains through an outlet tube 83 in the 
bottom thereof into a feed chamber 80. Providing liquid communication 
between outlet tube 83 in the bottom of the collection vessel 82 and the 
upper trough is a second feed tube 84. 
A drain tube 85 has a bottom end disposed in the lower trough 32 and an 
upper end attached to an upper overflow tube 86 that projects upwardly 
into the upper trough 31. Similarly, a discharge tube 88 has a bottom end 
disposed in the container 51 and an upper end attached to a lower overflow 
tube 89 projecting upwardly into the lower trough 32. 
The outlet portion 25 of the rear sidewall 16, the upper and lower troughs 
31, 32 and the upper and lower wick cartridges 34, 38 retained thereby 
constitute a integral unit 91 that is pivotably supported by the housing 
12. As shown in FIGS. 7 and 8, each side of the unit 91 has outwardly 
projecting spindles 92 that are received by bayonet type openings 93 
formed in straddling portions 94 of the housing 12. Each of the openings 
93 includes a vertical slot portion 95 and a horizontal slot portion 96. 
The spindles 92 are pivotably retained at the bottom of the vertical slots 
95 and permit pivotal movement of the unit 91 between a closed position 
shown in FIGS. 4 and an open position shown in FIG. 3. Resilient tabs 97 
projecting outwardly from the sides of the unit 91 engage the edges of the 
housing portions 94 to retain the unit 91 in its open position shown in 
FIG. 3. However, by moving the spindles 92 upwardly in the vertical slots 
95 to provide access to the horizontal slots 96 and forcing the resilient 
tabs 97 by the housing portions 94 the unit 91 can be fully separated from 
the housing 12. 
OPERATION 
Prior to use of the evaporator 11, the tank 61 is removed through the 
opened door 23 and filled with liquid through the filling spout 66 after 
removal of the cap 67. After replacement of the cap 67 on the spout 66, 
the tank 61 is inserted through the opened door 23 onto the support 
shoulders 53, 54 on the container 51. Upon full insertion of the tank 61, 
the actuator stem 69 forcibly engages the actuator surface 58 to open the 
valve 68 and produce discharge of the liquid within the tank 61 into the 
container 51. A given minimum liquid level within the container 51 moves 
the float mechanism 77 upwardly to close the switch 78 and permit 
energization of the fan motor 44 and the pump 76 in response to selective 
manipulation of the electrical control section 45. 
Energization of the pump 76 produces liquid flow out of the reservoir 52 
through the first feed tube 81, the collection vessel 82 and the second 
feed tube 84 into the upper trough 31. That liquid flow establishes a 
predetermined liquid volume in the upper trough 31 as determined by the 
height of the open upper end of the upper overflow tube 86. Additional 
liquid flow into the upper trough 31 is fed by gravity through the drain 
tube 85 into the lower trough 32 to establish therein a given liquid 
volume determined by the open upper end of the lower overflow tube 89. 
Additional liquid flow into the lower trough 32 is returned by gravity 
through the overflow tube 89 and the discharge tube 88 into the reservoir 
52. 
Water retained in the upper trough 31 saturates the source portion 35 of 
the upper wick cartridge 34 and capillary action produces migration of 
that liquid into the upper evaporative portion 36. Similarly, liquid 
retained in the lower trough 32 saturates the source portion 39 of the 
lower wick cartridge 38 and that liquid flows upwardly into the lower 
evaporative portion 41. Air flow provided by the rotating fan 43 moves air 
in through the inlet 21, the evaporative portions 36, 41 of respectively, 
the wick cartridges 34, 38 and the outlet 25. The liquid evaporated from 
the wick cartridges 34, 38 is transferred by the moving air into the 
surrounding environment to cause humidification thereof. 
If environmental cooling in addition to humidification is desired, the tray 
47 can be filled with ice through the opened lid 48. Cold liquid produced 
by melting of the ice in the tray 47 is fed by gravity through a drain 
opening 101 in the tray 47 into a transfer trough 102 disposed directly 
above the upper wick cartridge 34. Drain slots 103 in the bottom of the 
transfer trough 102 allow gravity induced flow of cooling liquid through 
the drain slots 103 into the upper evaporative portion 36 of the upper 
wick cartridge 34. Accordingly, air flow produced by the fan 43 through 
the upper evaporative portion 36 of the upper wick cartridge 34 is both 
cooled and humidified. 
For purposes of cleaning, it is sometimes desirable to remove the container 
51 from the housing 12. In that event, the tank 61 is removed through the 
opened door 23, and the pump assembly 73 is pivoted into an upright 
position above the rearwall 56 of the container 51 as shown by dashed 
lines in FIG. 5. The container 51 then can be removed through the opened 
door 23. 
Obviously, many modifications and variations of the present invention are 
possible in light of the above teachings. It is to be understood, 
therefore, that the invention can be practiced otherwise than as 
specifically described.