Aerator

Abstract

The aerator has a submersible mixing tube with a water inlet and an aerated water outlet. A suction tube penetrates the mixing tube between the water inlet and the aerated water outlet, the suction tube having an air outlet for introducing air into the mixing tube and an air inlet for drawing air from the atmosphere above the water surface. The mixing tube has an external motor lower unit engagement portion that engages the lower unit of an external motor during use, so that its propeller is located entirely inside the mixing tube with the middle portion of the external motor extending from the engagement portion. The external motor lower unit propeller therefore pushes water past the air inlet, thereby creating suction at the inlet that draws air through the mixing tube, mixing with the water and releasing a plume of aerated water.

Description

[Technical field]

[0001] The present invention relates generally to an improved aerator, and more specifically to an aerator having a submersible mixing tube configured for connection to a conventional external motor for low cost manufacturing and ad hoc deployment. [Background technology]

[0002] Aeration may be required in bodies of water with hypoxic or anoxic conditions and is accomplished by injection of air through surface agitation, which allows oxygen exchange at the surface of the body of water. Dissolved oxygen is a major contributor to water quality; not only is it required by fish and most other aquatic animals, it can also assist aerobic bacteria in breaking down organic matter. If dissolved oxygen levels get too low, anoxic conditions can develop that can reduce the ability of a body of water to support life.

[0003] There are many types of aeration methods, generally including surface or subsurface aeration, and there are several technologies and sciences available for both approaches. Subsurface aeration can include jet aeration, typically using a jet aerator that draws in air by utilizing the Venturi effect. Other subsurface aeration techniques can use coarse or fine bubble diffusers.

[0004] Surface aeration techniques may employ fountains or floating surface aerators.

[0005] However, either type of aerator is generally expensive to build, install, and maintain. For example, a surface aerator may include an electric motor mounted from a floating barge or weir that is expensive to manufacture and install. Furthermore, the electric motor must be powered by a shore source.

[0006] These types of aerators are not particularly suited for low-cost, ad-hoc applications where aeration may be needed quickly, temporarily and at low cost.

[0007] The present invention seeks to provide a method that will overcome or substantially ameliorate at least some of the disadvantages of the prior art, or at least provide an alternative.

[0008] Where prior art information is referenced herein, it should be understood that such reference does not constitute an admission that the information forms part of the common general knowledge in the art in Australia or any other country. Summary of the Invention

[0009] Provided herein is an aerator that includes a submersible mixing tube having a water inlet and an aeration water outlet. A suction tube enters the mixing tube between the water inlet and the aeration water outlet. The suction tube has an air outlet for introducing air into the mixing tube, and an air inlet for drawing air from the atmosphere above the water surface.

[0010] The mixing tube includes an external motor lower unit engagement portion that engages the lower unit of the external motor with the interior of the mixing tube such that the propeller of the external motor can rotate within the mixing tube, and an intermediate portion of the external motor extends from the engagement portion to a power head above the water surface of the external motor.

[0011] Thus, during use, the propeller of the external motor lower unit pushes water past the air inlet, creating suction that draws air in through the suction tube, which mixes with the water and expels a plume of aerated water through the aerated water outlet.

[0012] The aerator is of simple construction and therefore can be manufactured at low cost. The mixing tube can also be relatively easily and inexpensively transported and installed on commonly available external motors, including those mounted on boats, to temporarily or periodically aerate a body of water. The aerator does not require costly installation, as do the prior art aerators described above, and further does not require a shore power facility.

[0013] The external motor lower unit engagement portion may be configured to accommodate various types of external motors. The external motor lower unit engagement portion may include a channel that extends to the end of the mixing tube so that the lower unit can slide into it from the end of the mixing tube, allowing the channel to be narrower than the diameter of the propeller. Additionally, side gaskets may seal the edges of the channel against the external motor lower unit, thereby reducing or eliminating water flow through the channel.

[0014] In a preferred embodiment, the suction tube is slidably engaged within the sliding engagement so that the position of its air outlet can be controlled to find the maximum flow position that maximizes aeration. Thus, the air outlet can be located away from the propeller center point "dead zone". Furthermore, the maximum flow position can depend on the type of external motor and the propeller configuration.

[0015] In a further preferred embodiment, the external motor lower unit engagement allows for longitudinal position adjustment of the mixing tube lower unit. In an embodiment, the channel may be longer than the lower unit or a conventional lower unit and may include front and rear fixing brackets that fix to the leading and trailing edges of the lower unit. Thus, the lower unit may be fixed in place to control the position of the lower unit relative to the mixing tube. Thus, the location of the air outlet may be optimized relative to the position of the propeller to avoid or reduce unwanted cavitation. In this way, the air outlet may be located close enough to the propeller to experience greater flow rate and turbulence at this closer location, while still being far enough away from the propeller to avoid or reduce the possibility of cavitation.

[0016] Aerators are screened, increasingly larger diameter inlets that draw in water at low rates to protect aquatic life and avoid debris. guide The aerator may include an outlet guide that directs the plume of aerated water downward to increase aeration at greater depths.

[0017] According to one aspect, there is provided an aerator comprising a submersible mixing tube having a water inlet and an aeration water outlet, and a suction tube penetrating the mixing tube between the water inlet and the aeration water outlet, the suction tube having an air outlet for introducing air into the mixing tube, and an air inlet for drawing air from the atmosphere above the water surface, the mixing tube comprising an external motor lower unit engagement portion which engages a lower unit of an external motor in use, such that its propeller is located entirely inside the mixing tube with a middle portion of the external motor extended from the engagement portion, such that in use the propeller of the external motor lower unit pushes water past the air inlet, thereby creating a suction at the inlet which draws air through the mixing tube to mix with the water and emit a plume of aerated water.

[0018] The air outlet may be located between the external motor lower unit engagement portion and the aeration water outlet.

[0019] The suction tube may be angled relative to the longitudinal axis of the mixing tube.

[0020] The suction tube may be at an angle of about 45° to the longitudinal axis.

[0021] The suction tube may be angled to one side of the mixing tube.

[0022] The suction tube may be slidably engaged within the sliding engagement portion so that the position of its air outlet may be adjusted relative to the mixing tube.

[0023] The sliding engagement portion may include a block within the opening through which the suction tube may be slidably retained therein.

[0024] The aerator may further include a support arm that supports the upper end of the suction tube.

[0025] The support arm may be parallel to the suction tube and may hold a collar at the upper end of the suction tube within which the suction tube may be slidably held.

[0026] The external motor lower unit engagement portion may be configured to allow the longitudinal position of the external motor lower unit relative to the mixing tube to be adjusted during use.

[0027] The motor lower unit engagement portion may include a longitudinal channel within which the lower unit may be positioned at different positions along the length of the motor lower unit.

[0028] The aerator may further include front and rear fixing brackets that engage the front and rear edges of the external motor lower unit at locations along the channel.

[0029] The channel may extend through the end of the mixing tube.

[0030] The aerator may further comprise opposed longitudinal gaskets along the channel which, in use, close off adjacent edges of the external motor lower unit.

[0031] The aerator has an inlet with a gradually increasing diameter relative to the diameter of the mixing tube. guide The device may further include:

[0032] entrance guide may comprise a frusto-conical portion.

[0033] entrance guide may be provided with a screen at its entrance.

[0034] entrance guide may include an engaging collar for securing to the adjacent end of the mixing tube.

[0035] The aerator may further include an angled outlet guide at the aeration water outlet.

[0036] The angled outlet guide may include an engaging collar for securing to the adjacent end of the mixing tube.

[0037] According to another aspect, there is provided a method of aeration including an aerator as described herein, the method including inserting an external motor lower unit into the mixing tube such that its propeller is located inside the mixing tube, and driving the external motor to force water past an air inlet of the suction tube and aerate the water.

[0038] The method may include sliding the suction tube within the sliding engagement to optimize the location of the air outlet.

[0039] The method may include sliding the external motor lower unit within the sliding engagement to optimize a position of the external motor lower unit.

[0040] Optimizing the location of the external motor lower unit may include locating the external motor lower unit away from the air outlet to reduce or eliminate cavitation.

[0041] Inserting the external motor lower unit may include sliding the lower unit into a channel over an end of the mixing tube.

[0042] Other aspects of the invention are also disclosed.

[0043] Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0044] [Figure 1] 1 illustrates an aerator engaged with an external motor according to an embodiment. [Diagram 2] FIG. 2 shows a side view of the aerator. [Diagram 3] FIG. 2 shows an end view of the aeration water outlet of the aerator. [Figure 4] FIG. 2 shows an end view of the aerator water inlet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] The aerator 100 includes a submersible mixing tube 101 having a water inlet 106 and an aeration water outlet 108. The submersible mixing tube 101 may be made of a hardened plastic such as PVC. In a state The mixing tube 101 may be manufactured from lightweight stainless steel or carbon fiber, or the like.

[0046] The suction tube 116 enters the mixing tube 101 between the water inlet 106 and the aeration water outlet 108 .

[0047] The suction tube 116 has an air outlet 120 that introduces air into the mixing tube 101 , and an air inlet 117 that draws air from the atmosphere above the water surface above the submerged mixing tube 101 .

[0048] The aerator 100 further comprises an external motor lower unit engagement portion 122 that engages the lower unit 105 of the external motor 102 such that the middle portion 104 of the external motor 102 extends from the mixing tube 101 to the power head 103 above the water surface.

[0049] The external motor lower unit engagement portion 122 is preferably rigidly and substantially watertightly attached to the external motor 10. 2 The mixing tube 101 holds the lower unit 105 of the mixing tube 101. Additionally, the mixing tube 101 may be of sufficient diameter such that the entire lower unit 105, including the propeller 111 and skeg 110, can be accommodated inside the mixing tube 101. In an alternative embodiment, the mixing tube 101 has a smaller diameter and a slot therethrough to accommodate the skeg 110. However, in either approach, the mixing tube 101 has a sufficient diameter such that the propeller 111 can rotate completely inside the mixing tube 101.

[0050] The air outlet 120 of the suction tube 116 is connected to the propeller 11 of the external motor lower unit 105. 1is positioned between the aeration water outlet 108 and the external motor lower unit engagement portion 122 so as to push water past the air outlet 120 and draw air therefrom where the air mixes with the water to form a plume of aerated water that is pushed out of the aeration water outlet 108.

[0051] Referring to FIG. 2, the suction tube 116 may be angled at approximately 45° with respect to the longitudinal axis of the mixing tube 101 so that water flows partially tangentially past the air outlet 120, thereby creating a suction that draws air in from the air inlet 117.

[0052] Additionally, with reference to Figures 3 and 4, the suction tube 116 may be angled from the vertical axis to avoid the power head 103 of the external motor 102 behind it.

[0053] In a preferred embodiment, the suction tube 116 is slidably held within the sliding engagement portion 115 such that the insertion depth of the suction tube 116 into the mixing tube 101 can be optimized to find the position of maximum flow rate in the water pushed by the propeller 111, which can vary depending on the type of external motor.

[0054] In the embodiment, the sliding engagement portion 1 1 5 is an angled opening through which the suction tube 116 is slidably retained therein. have It may comprise a block.

[0055] In an embodiment, suction The support arm 11 may be parallel to the tube 116. 4 teeth, suction It may hold a collar 121 that supports the upper portion of the tube 116 .

[0056] The external motor lower unit engagement portion may include a channel 122 through which the lower unit 105 extends. Preferably, the channel 122 is , different Lower unit 105 of the same type and different types of external motors 102 It is wide enough to accommodate.

[0057] In an embodiment, opposing edges of channel 122 may be substantially sealed with a longitudinal rubber gasket 123 that closes around the edges of lower unit 105, thereby substantially reducing or eliminating water flow through channel 122.

[0058] In a preferred embodiment, the channel 122 is elongated, resulting in a uniform airflow between the propeller 122 and the air outlet 120. 11 In this regard, the location of the air outlet 12 may be controlled to generally experience greater flow rate and turbulence at this closer location and to shorten the overall length of the mixing tube 101. 0 The propeller 1 11 However, it is preferable to place it near the air outlet 12. 0 1 propeller 11 Therefore, according to this embodiment, in use, the external motor 1 0 Depending on the particular type of propeller 12, the longitudinal position of the lower unit 105 may be determined by the relative position of the propeller 12 with respect to the air outlet 120. 1 The position of 1 can be controlled to be optimized.

[0059] In an embodiment, the engagement portion 122 may include a front bracket 118 and a rear bracket 113 that support opposing front and rear edges of the lower unit 105 to hold the lower unit 105 in place. In an embodiment, each bracket 113, 118 may include upper and lower plates that have channels 116 and 118 for clamping the plates against the outer and inner surfaces of the mixing tube 101 to hold the brackets 113, 118 in place. 2 2 and having a fastener extending between them.

[0060] In an embodiment, the aerator 100 includes an inlet port with a gradually increasing diameter. guide 109, and a screen 124 at its entrance. Entrance Guide 109 may comprise a frusto-conical portion. guide 109 is a smaller flow rate than that inside the mixing tube 101 and is connected to the screen 12 4This allows water to be drawn in.

[0061] entrance guide 109 may include a collar 125 that fits over the end of the mixing tube 101 .

[0062] In the preferred embodiment, channel 1 2 2 extends straight to the rear edge 119 of the mixing tube 101 so that the lower unit 105 can be introduced into the mixing tube 101 from its rear open end, and the channel 1 2 2, propeller 1 1 In this regard, for the installation of the lower unit 105, the inlet guide 109 can be removed and replaced after sliding the lower unit 105 into place.

[0063] In an embodiment, the aerator 100 may further include an angled outlet guide 107 that may direct the aeration water downward to increase aeration at greater depth. Similarly, the angled outlet guide 107 may include a collar 126 that may fit over the adjacent end of the mixing tube 101.

[0064] The foregoing description, for purposes of explanation, used specific terminology to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required to practice the present invention. Thus, the foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously, many modifications and variations are possible in light of the above teachings. The embodiments have been chosen and described in order to best explain the principles of the invention and its practical application, so as to enable others skilled in the art to best utilize the invention and its various embodiments, with various modifications, as appropriate for the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.

[0065] The term "about" or similar terms, as used herein, unless otherwise indicated, should be interpreted as within 10% of the stated value.

Claims

1. 1. An aerator comprising: a submersible mixing tube having a water inlet and an aeration water outlet; and a suction tube entering the submersible mixing tube between the water inlet and the aeration water outlet, the suction tube having an air outlet for introducing air into the submersible mixing tube and an air inlet for drawing air from the atmosphere above the water surface, the suction tube is slidably engaged within a sliding engagement portion so that a position of the air outlet of the suction tube can be adjusted relative to the submerged mixing tube; The submersible mixing tube comprises an external motor lower unit engagement portion which engages a lower unit of an external motor during use, such that a propeller of the external motor lower unit is located entirely inside the submersible mixing tube with a middle portion of the external motor extending from the external motor lower unit engagement portion, such that during use the propeller of the external motor lower unit pushes water past the air outlet, thereby creating a suction at the air inlet which draws air through the submersible mixing tube to mix with the water and release the aerated water from the aeration water outlet.

2. 2. The aerator of claim 1, wherein the air outlet is located between the external motor lower unit engagement portion and the aeration water outlet.

3. 3. The aerator of claim 2, wherein the suction tube is at an angle to a longitudinal axis of the submersible mixing tube.

4. 4. The aerator of claim 3, wherein said suction tube is at a 45 degree angle to said longitudinal axis.

5. 2. The aerator of claim 1, wherein the suction tube is angled laterally from a vertical axis of the submersible mixing tube.

6. 2. The aerator of claim 1, wherein the sliding engagement portion comprises a block having an opening through which the suction tube is slidably retained therein.

7. 4. The aerator of claim 3, further comprising a support arm supporting an upper end of the suction tube.

8. 8. The aerator of claim 7, wherein the support arm is parallel to the suction tube and carries a collar at an upper end of the suction tube within which the suction tube is slidably held.

9. 2. The aerator of claim 1, wherein the external motor lower unit engagement portion is configured to allow adjustment of the longitudinal position of the external motor lower unit relative to the submersible mixing tube during use.

10. 10. The aerator of claim 9, wherein the external motor lower unit engagement portion comprises a longitudinal channel along which the external motor lower unit may be positioned at different positions.

11. 11. The aerator of claim 10, further comprising front and rear locking brackets that engage leading and trailing edges of the external motor lower unit at locations along the longitudinal channel.

12. 11. The aerator of claim 10, wherein the longitudinal channel extends through an end of the submersible mixing tube.

13. 11. The aerator of claim 10, further comprising opposing longitudinal gaskets along the longitudinal channel that close adjacent edges of the external motor lower unit during use.

14. 10. The aerator of claim 1 further comprising an inlet guide that increases in diameter relative to a diameter of the submersible mixing tube.

15. 15. The aerator of claim 14, wherein the inlet guide comprises a frusto-conical portion.

16. 16. The aerator of claim 15, wherein the inlet guide includes a screen at its inlet.

17. 16. The aerator of claim 15, wherein the inlet guide includes an engaging collar for securing to an adjacent end of the submersible mixing tube.

18. 10. The aerator of claim 1, further comprising an angled outlet guide at the aeration water outlet.

19. 20. The aerator of claim 18, wherein the angled outlet guide includes an engaging collar for securing to an adjacent end of the submersible mixing tube.

20. 2. A method of aeration including the aerator of claim 1, comprising: inserting an external motor lower unit into the submersible mixing tube such that a propeller of the external motor lower unit is located inside the submersible mixing tube; and driving the external motor to push water past the air outlet of the suction tube and aerate the water; The method further includes sliding the suction tube within a sliding engagement portion to optimize a position of the air outlet. method.

21. 21. The aeration method of claim 20, further related to the aerator of claim 9, the method further comprising sliding the external motor lower unit within a sliding engagement to optimize a position of the external motor lower unit.

22. 22. The aeration method of claim 21, wherein optimizing the location of the external motor lower unit includes locating the external motor lower unit away from the air outlet to reduce or eliminate cavitation.

23. 21. The method of claim 20 further comprising the aerator of claim 12, wherein inserting the external motor lower unit comprises sliding the external motor lower unit into the longitudinal channel over an end of the submersible mixing tube.

Images