Patent Grant
7789633
The present invention relates in general to nozzle regulators and more particularly to a nozzle regulator constructed of a deformable material and for use in a venturi pump that automatically adjusts its output area as needed to provide an increased suction force at an inlet of the venturi pump.
Venturi pumps are useful devices that are utilized in a myriad of situations and applications. For example, venturi pumps are used in industrial applications and on construction sites to pump an assortment of fluids. In home applications, venturi pumps are used to drain pools, fountains, ponds, aquariums, sinks and in innumerable other applications.
Venturi pumps make use of a venturi to pump fluids from one area to another. In general, a venturi is a short tube having a tapering constriction (or throat) at or near the middle of the tube. This constriction causes the velocity of the fluid at the throat to increase and a corresponding decrease in fluid pressure. The low-pressure area created at the throat is particularly useful in measuring fluid flow and for creating a suction force. This suction force is used in many applications, such as for driving aircraft instruments and for drawing fuel into the flow stream of a carburetor.
One type of venturi pump that makes use of a venturi to create a suction force and draw fluid into the pump is discussed in U.S. Pat. No. 4,963,073 by Tash et al. entitled, “Water Pressure Operated Water Pump”. Disclosed therein is a convenient, easy-to-use and inexpensive pump for pumping water. The device uses water pressure from a standard garden hose connection as the power to pump the water. The device has a primary inlet, a secondary inlet, and an outlet nozzle. The primary inlet is for inputting liquid (such as water from a garden hose tap) at a high velocity through a venturi. This high-velocity flow creates a low-pressure area at the throat and generates the motive power necessary to drive the pump. The secondary inlet is positioned at the throat and opens into the venturi at the throat. The fluid being pumped is drawn into the venturi through the secondary inlet. The output nozzle is for outputting the fluid combination from the primary and secondary inlets.
When the water from the garden hose tap flows under pressure into the primary inlet, the velocity of the water is greatly increased by a venturi that is positioned in the pumping chamber. The increased velocity of the water through the venturi causes a corresponding drop in pressure. This drop in pressure causes the pressure in the pumping chamber to be less than the pressure of the fluid to be pumped. This causes the fluid being pumped to be drawn through the secondary inlet into the pumping chamber and be ejected through the outlet nozzle.
In existing venturi pumps, the cross-sectional areas of the primary inlet, secondary inlet, throat, and outlet nozzle are fixed. This means that the inlet-to-throat area ratio and the throat-to-outlet nozzle area ratio are fixed. This leads to at least three problems with existing venturi pumps.
First, when a column of fluid (or head) at the outlet nozzle is high enough, the pump will be unable to pump the fluid any higher. This is because the motive force pumping the fluid through the outlet nozzle is in equilibrium with the weight of the fluid head at the outlet nozzle. A second problem with conventional venturi pumps is that if debris or other contaminants (such as leaves or rocks) block the secondary inlet the flow rate decreases and the pump performance suffers. In addition, viscous fluid (such as oil or a combination of water and mud) requires greater suction in the pumping chamber than a less viscous fluid (such as water). A third problem is that a rigid foreign object in the fluid being pumped (such as a rock) may be sucked through the secondary inlet and lodge in the outlet nozzle. In extreme situations, the foreign object may completely block the outlet nozzle, thereby effectively shutting down the pump. Therefore, what is needed is an improved venturi pump that overcomes the aforementioned problems to provide increased performance and usefulness without undue cost and complexity.
The automatically deformable nozzle regulator described herein is designed for use in a venturi pump. The nozzle regulator is constructed of a deformable material and automatically decreases its output area as needed to decrease the pressure at an inlet of the venturi pump and provide increased suction force. This increased suction force allows a venturi pump utilizing the present invention to overcome the aforementioned problems and provide increased performance and usefulness without undue cost and complexity.
In particular, the present invention helps alleviate the problem of debris blocking an inlet of the venturi pump. In this situation, as the resistance at the inlet increases, the output velocity of the fluid exiting the deformable nozzle regulator decreases, leading to a pressure increase (or fluid backpressure) around the nozzle regulator. This fluid backpressure imposes a constricting force on the nozzle regulator and reduces its output area. This in turn increases the venturi effect and provides an increased low-pressure area (or suction force) at the inlet such that any debris is dislodged, fragmented or disintegrated.
The present invention also alleviates the situation where the head is so great that the venturi pump is unable to pump fluid any higher. The increase in backpressure caused by the increased head causes the nozzle regulator to constrict or shrink, thereby increasing fluid velocity through the nozzle regulator. This often is enough to increase the height to which the venturi pump can raise the fluid. Moreover, the deformable nozzle regulator is better able than rigid nozzle regulators to deal with hard obstructions that may enter the venturi pump. The present invention is able to pass these obstructions more easily than fixed and rigid outlet nozzles. Once the obstruction has passed, the nozzle regulator returns to its original shape.
In general, the nozzle regulator contains three sections. Namely, an outer tubular section or cylinder, an inner tubular section or cylinder, and an inlet section. The outer cylinder and the inner cylinder are concentric. The nozzle regulator also contains an output nozzle. This output nozzle is formed by the offset to an outlet side of the inner cylinder such that the inner cylinder projects a distance from the outer cylinder. This projection of the output nozzle aids the nozzle regulator in taking full advantage of the backpressure effect.
The inlet section is a ring or disc having a convergent cross-sectional shape that joins the outer cylinder and the offset inner cylinder at an inlet side. The convergent cross-sectional shape of the inlet section can be a convex curve or a straight line. The nozzle regulator also includes a nozzle regulator cavity formed by the junction of the three above sections. Specifically, the cavity is formed by the space between the outer cylinder and the inner cylinder and bounded on the inlet side by the inlet section, while remaining open at the outlet side.
The present invention can be further understood by reference to the following description and attached drawings that illustrate aspects of the invention. Other features and advantages will be apparent from the following detailed description of the invention, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the present invention.
Referring now to the drawings in which like reference numbers represent corresponding parts throughout:
In the following description of the invention, reference is made to the accompanying drawings, which form a part thereof, and in which is shown by way of illustration a specific example whereby the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.
I. General Overview
The automatically deformable nozzle regulator described herein is designed to operate in a venturi-type pump. One such pump in which the invention may be used is described in U.S. Pat. No. 4,963,073 by Tash et al. entitled, “Water Pressure Operated Water Pump”, the entire contents of which are hereby incorporated by reference. Throughout this specification, this venturi pump will be used to illustrate the operation of the automatically deformable nozzle regulator. It should be understood, however, that the automatically deformable nozzle regulator described herein may be used with other venturi-type pumps.
When incorporated into the venturi pump described in U.S. Pat. No. 4,963,073, the automatically deformable nozzle regulator transforms the venturi pump into an outlet side regulated venturi pump. This is achieved because the nozzle regulator of the present invention is made from a deformable material (such as rubber). Because the nozzle regulator is deformable, the throat-to-outlet area ratio is capable of being changed. In particular, the area of the outlet nozzle can be decreased by deformation of the nozzle regulator such that the throat-to-outlet area ratio is increased. From Bernoulli's equation, it follows that an increase in the throat-to-outlet area ratio leads to a decrease in pressure at the throat.
Once incorporated into the venturi pump described above, the automatically deformable nozzle regulator automatically determines when additional suction force (or low pressure) is needed at the throat and decreases its output area accordingly. As explained in detail below, this automatic determination is a physical phenomenon based on backpressure that the nozzle regulator experiences. Because the nozzle regulator is deformable, an increase in backpressure constricts the nozzle regulator and decreases its outlet area, thereby lowering the pressure at the throat and creating additional suction force.
In particular, as shown in
An outlet line 150 is connected to the outlet side of the pump 115 containing the automatically deformable nozzle regulator 105. The height of the output water (“h”) within the outlet line 150 is known as the “head.” Water output from the pump 115 is pushed through the outlet line 150 and at an outlet line end 155 to an area outside of the tank 120. In this manner, the water 125 is removed from the tank 120 by the pump 115.
II. Incorporation of the Automatically Deformable Nozzle Regulator
The automatically deformable nozzle regulator of the present invention is designed to be incorporated into the outlet area of a venturi pump.
As shown in
III. Structural Details of the Automatically Deformable Nozzle Regulator
The details of the shape of the nozzle regulator 105 will now be discussed. In general, the nozzle regulator 105 contains three sections: (1) an outer tubular section or cylinder 400; (2) an inner tubular section or cylinder 410; and, (c) an inlet section 420. In particular, the outer tubular cylinder 400 has a first radius, router, and the inner tubular cylinder 410 has a second radius rinner, with router>rinner. The outer cylinder 400 and the inner cylinder 410 are concentric about a longitudinal axis, shown in
The inlet section 420 smoothly connects the outer cylinder 400 and the inner cylinder 410 at the inlet side 430. The inlet section 420 essentially is a ring or disc having a convergent cross-sectional shape (along the longitudinal axis a-a) that joins the outer cylinder 400 and the offset inner cylinder 410 at the inlet side 430. In other words, moving from the inlet side 430 to the outlet side 440 the cross-sectional shape of the inlet section 420 converges. This convergence can be seen by referring to
In a preferred embodiment shown in
The junction of the three above sections forms a nozzle regulator cavity 450 in the nozzle regulator 105. This cavity 450 is formed by the space between the outer cylinder 400 and the inner cylinder 410 and bounded on the inlet side 430 by the inlet section 420. At the outlet side 440 the cavity 450 is open. Within the inner cylinder 410 is a fluid passageway 470 where the fluid being pumped flows through the nozzle regulator 105.
IV. Operation of the Automatically Deformable Nozzle Regulator
The automatically deformable nozzle regulator described herein automatically adjusts its output area as needed to provide an increased low-pressure area at an inlet of the venturi pump. This change in output area is achieved by decreasing the radius of the inner cylinder, rinner, at the outlet side 440 such that the output area is decreased. This decrease in the inner cylinder radius, rinner, is achieved using backpressure from the fluid. Because of the deformable nature of the nozzle regulator 105, when the backpressure is great enough the inner cylinder radius, rinner, constricts thereby decreasing rinner. Once the backpressure is relieved, the deformable nature of the nozzle regulator 105 causes rinner to return to its original value.
The details will now be explained with reference to
The backpressure effect causes the radius of the outlet nozzle 445 to decrease, as shown by the arrows in
Another situation that may occur is the situation where the head, h, in the outlet line 150 is so high that the pump 115 is unable to pump fluid any higher. This occurs when motive force pumping the fluid through the outlet line 150 is in equilibrium with the weight of the fluid in the head. As the head of the outlet line increases, however, the backpressure also increases. The increase in backpressure occurs in the nozzle cavity and around the outside of the output nozzle 445. This increase in backpressure causes the outlet nozzle 445 to constrict or shrink because of a “backpressure pocket” that develops within the nozzle regulator cavity 450. The inner cylinder radius at the output nozzle 445 decreases causing an increase in fluid velocity at the output nozzle 445. This increase in fluid velocity often is enough to increase the height to which the pump 115 can raise the fluid.
Yet another situation occurs when a rigid foreign object in the fluid being pumped (such as a rock) is drawn through the secondary inlet 140. Because the nozzle regulator 105 is constructed of a deformable material, the nozzle regulator 105 is able to pass debris more easily than fixed and rigid outlet nozzles. Due to it deformable nature, the inner cylinder 410 is able open up (expand) to allow the debris to pass easily through the nozzle regulator 105. The inner cylinder 410 then returns to its original shape once the obstruction has passed.
The foregoing description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description of the invention, but rather by the claims appended hereto.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3605672 | Strumbos | Sep 1971 | A |
| 3667069 | Blackshear et al. | Jun 1972 | A |
| 4963073 | Tash | Oct 1990 | A |
| 6250890 | Popov | Jun 2001 | B1 |
| Number | Date | Country | |
|---|---|---|---|
| 20040258535 A1 | Dec 2004 | US |
