Aeration and filtration pump for aquariums

An aeration and filtration pump for aquariums, including a housing formed with openings through which the aerated and filtered air can return to the aquarium tank, and an impeller enclosure member positioned within the housing. The impeller enclosure member includes an intermediate portion and an upper portion formed with spaced openings, with a screw impeller being positioned within said intermediate region of said enclosure member for impelling water upwardly within said member. Air impeller means are mounted above the screw imepller and force air drawn into said housing downwardly form aerating the water impelled upwardly by the screw impeller. Water is admitted to the bottom of the unit, and filter material is positioned between the converter member and the housing, with the aerated water passing through the filter material and the openings in the housing wall for return to the tank.

BACKGROUND OF THE INVENTION 
The present invention relates as indicated to an aquarium power pump, and 
relates more particularly to a pump specifically designed to provide new 
and improved aeration and filtration of the water passing inwardly of and 
outwardly from the pump for return to the aquarium water supply. 
The aeration and filtering of aquarium water through a pumping device is 
per se old in the art. For example, U.S. Pat. No. 2,533,936 to Holmes et 
al. discloses a pump for an aquarium in which the water drawn upwardly 
through the pump housing is first filtered and then discharged as 
circulating water through a nozzle or jet. In addition, water is 
discharged above the level of the water in the tank in a series of fine 
jets to further increase the aeration effect. 
U.S. Pat. No. 3,374,990 to Gray; U.S. Pat. No. 3,295,681 to Rubert et al, 
and U.S. Pat. No. 3,924,570 to Lamonica likewise show aerating and/or 
filtering means for aquarium pumps, and further show the state of the art 
with regard to these features. However, all of the noted art possess 
certain disadvantages with respect principally to cost and results 
achieved, and the present invention is specifically designed to overcome 
these disadvantages. 
SUMMARY OF THE INVENTION 
With the above in mind, a principal object of the invention is to provide a 
compact power pump designed for improved aeration and filtration, while at 
the same time being simple and thus inexpensive to manufacture and 
install. Due to the efficient operation of the pump, it can be 
manufactured of relatively reduced size and weight thereby permitting the 
same to be mounted on the top of the aquarium which may be constructed of 
glass or plastic. The pump unit is submerged in the tank water and 
functions to circulate, filter and aerate the water in the tank. Means are 
provided for controlling the air supply to the pump housing thereby 
controlling the degree of aeration of the circulated water through the 
device and back to the tank. 
A principal feature of the invention is an impeller enclosure member which 
is positioned within the pump housing and which is constructed and 
arranged so as to receive water from the tank to be recirculated and to 
direct the same through a reduced diameter intermediate region in which an 
impeller is rotatably mounted. The upper portion of the impeller enclosure 
member is generally cone-shaped, comprising a plurality of segments spaced 
from each other so as to permit the aerated water to flow through said 
spaces or openings into the filter material positioned around the 
enclosure member and within the pump housing. The latter is provided with 
a plurality of openings in the side wall thereof through which the aerated 
and filtered water can pass for return to the tank. 
A motor preferably mounted at the top of the aquarium drives the impeller, 
and rotatably carried by the same drive shaft are individual fan propeller 
blades which function when rotated to form a downward current. Atmospheric 
air can be controllably admitted to the region of the impeller member 
above the fan propeller blades, with the result that the air is driven 
downwardly for intimate mixing with the water impelled upwardly by the 
impeller. The water thus impelled is highly aerated before passing from 
the enclosure member through the filtering means and the openings in the 
housing for return to the tank. 
These and other objects will be apparent as the following description 
proceeds, in particular reference to the application drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to the application drawing, wherein like parts are indicated 
by like reference numerals, the pump is suspended from the top platform 2 
of the aquarium, and also mounted on the platform is a housing in which is 
positioned an electric motor 1 having a motor shaft 24. The pump comprises 
an outer housing 3 within which is a filter chamber 4 which contains 
fibrous and porous material 5 for filtering the water. The housing 3 is 
formed with a plurality of openings 18 through which the filtered and 
aerated air returns to the housing. 
Mounted within the housing 3 is an impeller enclosure member 10 which 
includes a conical lower end 11, a diametrically reduced intermediate 
section 12, and a conical upper portion 14 comprised of individual, spaced 
conical segments commonly designated at 16. The entire height of the 
enclosure member 10 is approximately the height of the housing 3, whereby 
the bottom cone portion 11 fits snugly into the bottom of the housing and 
serves as a funnel-shaped entry area for water drawn into the pump unit. 
The spaces between the conical segments 16 in the upper region 14 of the 
enclosure member permit the aerated water to pass therethrough, and hence 
through the filter material 5 and the openings 18 for return to the tank. 
A screw impeller 6 is carried by a drive shaft 7, which is coupled at 20 to 
the motor shaft 24. The screw impeller is relatively snugly received in 
the intermediate portion 12 of the enclosure member. The shaft 7 is 
rotatably driven by the motor 1, and also rotatably carries a series of 
propeller blades 15, positioned approximately intermediate the top and 
bottom of the upper section 16 of the converter member. The rotation of 
the fan propeller 15 results in the formation of a downward current, which 
opposes the upward thrust of the water carried by the screw impeller 6 
through the intermediate portion 12 of the enclosure member, and ambient 
air can enter the housing within the top portion 16 of the converter 
member by means of passage 17 and a passage formed in a bleeding valve 22 
which regulates the flow of the air. Since the multibladed fan propeller 
rotates in the relatively more open region of the enclosure member, as 
compared with the restricted passage through the intermediate region 12, 
the thrust of the fan propeller 15 is easily diffused to reconcile with 
the main, upward current of water conveyed by the screw impeller. In this 
manner, the power of both the screw impeller and fan propeller 15 is not 
impeded, and the aerated water flows through the openings between the 
segments 16 of the enclosure member 10. 
To provide for the entrance of water to the pump, a bottom cap 8 is 
positioned over and encloses the open bottom of both the pump housing 3 
and the enclosure member 10, with the cap being secured to the housing in 
any suitable manner. The cap is formed with a series of openings 9 through 
which the water can be admitted to the bottom conical section 11 of the 
enclosure member 10 for passage to the restricted section 12 of such 
member for conveyance by the screw impeller. The cap is also formed with a 
central recess 21 (FIG. 3) which serves to receive and centrally align the 
shaft 7 thereby centering the screw impeller relative to the enclosure 
member and the housing. The outside diameter of the bottom of the conical 
lower portion 11 is only slightly less than the inside diameter of the 
housing 3, and the same applies to the diameter at the top of the upper 
segmented portion 16 of the enclosure member relative to the housing, 
whereby the enclosure member is at all times properly positioned in the 
housing so as to align the intermediate region 12 thereof with the screw 
impeller. As noted, the cap 8 can be secured to the housing in any 
suitable manner such as by a threaded connection, and when the cap is 
threaded in place and tightened, all parts of the pump unit are in 
position for operation. A multi-speed switch 23 is operably connected (not 
shown) to the motor 1 for regulating the speed thereof, which in turn 
regulates the aeration and filtration processes. 
The operation of the aquarium pump constructed in accordance with the 
invention should be apparent from the above description. To briefly 
summarize, water is admitted to the pump housing through the openings 9 in 
the cap 8, and the water is thrust upwardly by the screw impeller 6 into 
the upper portion of the impeller enclosure member. At the same time, air 
is admitted to the unit through the valve 22, and a countercurrent force 
is created by the propeller blades 15, which are mounted on the shaft 7 
and rotated simultaneously with the screw impeller. Although these 
opposing forces are therefore counteractive, the rotation of the propeller 
15 in the relatively enlarged upper portion 14 of the enclosure member 
does not impede the power of the unit, and the thrust of the water 
emanating from the restricted region 12 of the enclosure member results in 
the water intimately mixing with the air admitted to the housing thereby 
causing the water to be highly aerated before passing through the filter 
area surrounding the enclosure member for return to the aquarium tank. The 
amount of air admitted to the housing can be adjusted by valve 22 thereby 
to provide optimum operating conditions. 
In addition to providing improved aeration and filtration, the pump unit is 
extremely simple in construction and thus inexpensive to manufacture. The 
interior of the unit is comprised essentially of the impeller enclosure 
member, the shaft 7 and the screw impeller 6 and propeller blades 15 
mounted thereon. These components can be readily assembled within the 
housing and secured in assembled position by the bottom cap 8. If 
disassembly is desired for cleaning or changing the filter material, the 
reverse procedure is followed, and it will be noted that to either 
assemble or disassemble the unit, no special tools of any kind are 
required. 
Minor changes may occur to those skilled in the art without, however, 
departing from the spirit or intent of the invention as above described. 
For example, the impeller enclosure member could be slightly modified from 
its illustrated form while maintaining the principal described features 
thereof in accordance with the invention. Likewise, more than two impeller 
systems could be coaxially connected to the same power unit to achieve the 
desired results.