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(11) | EP 1 607 634 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | System for recovering viscous fluid from containers |
| (57) A residual fluid extraction device is provided for recovering residual fluids, such
as oil from a container. The device includes an air injection tube for injecting heated
air through a mouth of the container and a fluid recovery receptacle for receiving
fluid from the mouth of the container. A method for conserving residual fluid from
a container having a mouth is also provided. |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 60/580,522, filed June 17, 2004, which is incorporated by reference herein as if fully set forth.
BACKGROUND
[0002] This invention generally relates to the recovery of residual viscous fluids, especially viscous lubricating fluids, from seemingly emptied containers.
[0003] Viscous lubricating fluids stored in a variety of containers are used in the maintenance and service of mechanical devices. For example, large quantities of motor and transmission oils are consumed each year for the maintenance of private and commercial vehicles. Often such fluids are distributed in small containers, 1-5 quarts in size, which are discarded after most of their contents are poured into a vehicle or other mechanism. Typically, depending on a fluid's viscosity, a significant amount of residual fluid remains in a discarded container. This wasted fluid is costly for the consumer. Many lubricating fluids, such as motor and transmission oils, are potentially damaging to the environment and may contaminate soil and water.
[0004] All other variables being equal, a fluid having a lower viscosity exits a container faster than a fluid having a higher viscosity. Accordingly, decreasing the viscosity of a fluid being dispensed from a container will result in more of the fluid being dispensed over a given period of time and result in less residual fluid remaining in the container after dispensing is complete. A fluid's viscosity is determined in large part by its temperature. As a fluid's temperature increases its viscosity decreases. It follows that as a fluid's temperature increases, the speed at which it is dispensed from a container increases.
[0005] A number of quantitative expressions are available for estimating the viscosity of fluids. Some of these expressions are set forth below in Table 1. Figure 18 shows four (4) plots of predicted viscosity of SAE 30 motor oil determined using equations found in Table 1 and one (1) plot determined by actual experimentation.
Table 1
| Year | Attributed person | Equation | Constants |
| 1883 | Petroff | µ = |
Constants A, c1 and c2 are empirically derived |
| 1886 | Reynolds | µ = Ae-mT | A is viscosity at T=0, m is 2.3 times the downward slope of log µ vs. T |
| 1890 | Slotte | µ = |
c is cold point temperature (apparent solidification) |
| 1922 | Vogel | A is viscosity as T approaches infinity, m is slope of log µ vs. 1/(T-c) with c found by trial | |
| 1932 | Walther | log(v+c)= |
is on absolute scale, c=0.8 centistokes |
[0006] The functions of Table 1 do each provide an asymptotic value of viscosity as temperature (T) approaches infinite. However, in mathematical terms, a minimum value is not achieved at a finite temperature value. As an engineering approximation, a minimum value of viscosity will be achieved at a finite temperature. Mathematically defined, as shown in Equation 1 below, the instantaneous slope (first derivative) of a viscosity-temperature curve will be within a value epsilon (ε) of zero (or an acceptable deviation (ε) from zero) at a target temperature Tt.
[0007] In other words, dµ/dT would ideally be equal to zero (indicating a perfectly flat or horizontal slope), but it would be acceptable to have the slope of the µ versus T curve at a mild incline (indicating that e is a relatively small value).
[0008] It would be desireable to provide a device and method for decreasing the viscosity of residual fluid within a fluid container for retrieving residual fluid from the fluid container.
SUMMARY
[0009] The present invention provides a residual fluid extraction device. The device includes an air injection tube for injecting heated air through a mouth of a container and a fluid recovery receptacle for receiving fluid from a mouth of a container. The present invention also provides a method for conserving residual fluid from a container. The method includes inverting the container, positioning a mouth of the container over a fluid recovery receptacle, and introducing a medium through the mouth of the container for decreasing the viscosity of the residual fluid.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0010] Figure 1 is an isometric view of a fluid extraction device according to a first preferred embodiment of the present invention.
[0012] Figure 3a is an isometric view of air injection and fluid recovery tubes of the fluid extraction device of Figure 1.
[0014] Figure 3c is a cross-sectional view of the air injection and fluid recovery tubes taken along lines 3c-3c of Figure 3b.
[0015] Figure 3d is a partial cross-sectional view of the device of Figure 1 taken along lines 3d-3d of Figure 1 showing the air injection and fluid recovery tube and a container.
[0016] Figure 4 is a partial enlarged view of the air injection tip from the view shown in Figure 3c further including air flow lines.
[0017] Figure 5 is an isometric view of an omni-directional nozzle included with the air injection tube.
[0018] Figure 6 is a perspective view of a fluid extraction device according to a second preferred embodiment of the present invention.
[0019] Figure 7 is a perspective view of the fluid extraction device of Figure 6 shown in an installed position on a motor vehicle engine.
[0020] Figure 8 is an elevational view of a heat scavenging connector of the fluid extraction device of Figure 6 shown in an installed position on an engine component.
[0021] Figure 9 is an isometric view of a fluid extraction device according to a third preferred embodiment of the present invention.
[0024] Figure 12 is an elevational view of the fluid extraction device of Figure 9 shown with its solar energy collection panel in an articulated position.
[0027] Figure 15 is an elevational view of a radiant heat tube and a fluid recovery tube of a fluid extraction device according to a fourth preferred embodiment of the present invention.
[0028] Figure 16 is a cross-sectional view of the radiant heat tube and the fluid recovery tube taken along lines 16-16 of Figure 15.
[0030] Figure 18 is a graph of viscosity versus temperature for SAE-30 motor oil which shows calculated and experimental data.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0031] Certain terminology is used in the following description for convenience only and is not considered limiting. Words such as "front", "back", "top" and "bottom" designate directions in the drawings to which reference is made. This terminology includes the words specifically noted above, derivatives thereof and words of similar import. Additionally, the terms "a" and "one" are defined as including one or more of the referenced item unless specifically noted. The phrase "at least one" followed by a list of two or more items (such as A, B, or C) means any individual one of A, B or C as well as any combination thereof.
[0032] The preferred embodiments of the present invention are described below with reference to the drawing figures where like numerals represent like elements throughout.
[0033] Figure 1 shows a residual fluid extraction device 10 according to a preferred embodiment of the invention. The extraction device 10 is configured to receive a container 50, or a plurality of containers, for the purpose of extracting residual fluids from the container.
[0034] Referring to Figures 1-5, the extraction device 10 includes a plurality of air injection tubes 12, each passing through a fluid recovery tube 14 which functions as a receptacle for fluid extracted from the container 50. The air injection tube 12 sealably enters through a side wall of the fluid recovery tube 14 and extends substantially concentrically through an inlet 16 of the fluid recovery tube 14. However, it could be offset to one side if desired. An omni-directional nozzle 20 including a plurality of dividing vanes 22 is positioned at an end of the air injection tube 12 for generally evenly discharging air perpendicular to the air injection tube 12 in proximity to the inverted bottom of an oil container 50.
[0035] The fluid recovery tube inlet 16 preferably includes stops 18, shown in Figures 3c and 3d, for resting a mouth 52 of the container 50 placed on the device 10. Alternatively, the stops 18 may be omitted, and the omni-directional nozzle 20 may provide support for the container 50 by bearing against an inner wall of the container 50. The recovery tube 14 is connected to a reservoir 30 which collects oil discharged from a container placed on the device 10.
[0036] As shown in Figures 1 and 2, an air mover 24 is connected to a manifold 26 which houses a heater 28 for heating air drawn into the device by the air mover. The air mover 24 is preferably a single-stage fan-type blower. However, a positive displacement blower or any type of air moving device may be used. Preferably, an air filter 32 is provided to filter air entering the air mover 24. Alternatively, the air mover 24 may be omitted and an air supply provided from an external source, such as a conventional air compressor. In such a case, an interface would be provided on the device 10 to receive air supply from a standard coupling. Preferably, the heater 28 is an electric resistance heater powered by alternating current household power, direct current from a vehicle battery or photovoltaic cells, or any suitable power source. Alternatively, other heating devices may be used in place of or in addition to an electric resistance heater to heat air, such as devices which scavenge air from a hot exhaust manifold or draw air past a solar heat energy collector. Such alternative devices are discussed in detail below.
[0037] Preferably, the manifold 26, reservoir 30, air injection and fluid recovery tubes 12, 14, parts of the air mover 24 and other device structure are formed of molded plastic. Alternatively, metals, ceramics, composites or any combination of suitable materials may be used to form the various components, such as by machining, casting or molding, and the parts are then joined to form the device 10.
[0038] In use, a container 50, such as a motor oil container, which has been seemingly drained of its contents, is placed on the device 10 with the air injection tube 12 extending into an interior of the container 50 through its mouth 52. Multiple containers of various shapes and sizes may be placed on the device. In the embodiment shown, up to six containers can be received by the six air injection tubes 12 and six fluid recovery tubes 14. Those skilled in the art will recognize that the device may be configured to receive more or less containers by varying the number of air injection and fluid recovery tubes 12, 14. As shown in Figure 1, dust caps 34 are provided to prevent air loss through the air injection and fluid recovery tubes 12, 14 which are not in use.
[0039] After the container(s) 50 are in place, the air mover 24 is activated, producing a flow of air through air filter 32 and past the heater 28 within the manifold. Heated air passes from the manifold into the air injection tube 12, and exits the air injection tube 12 through the omni-directional nozzle 20 into the interior of the container(s) 50. The omni-directional nozzle 20 directs the heated air such that it flows along the inside walls of the container(s) 50, as shown by dashed arrows in Figure 2. In this manner, fluid retained on the inside walls of the container(s) 50 increases in temperature and therefore decreases in viscosity. Preferably, the fluid temperature is increased to a target temperature (Tt) at which the fluid viscosity is approximately minimized. This decrease in viscosity allows the fluid to more easily flow by the force of gravity through the container mouth 52 and into the fluid recovery tube 14, as shown by solid arrows in Figure 2. The omni-directional nozzle prevents oil from falling from a top inside wall of the container 50 into the air injection tube 12. Fluid recovered from the container passes through the fluid recovery tube 14 and into the reservoir 30 where it may be stored and/or discharged through a drain 34. Using the system 10, the original contents of the container that would otherwise be discarded can be recovered. Preliminary testing has shown that 1-4% of viscous fluid remains as a residual content in lubricating oil containers which have been seemingly emptied of their contents. The proposed system 10 is configured to retrieve a significant portion of this residual fluid.
[0040] Referring now to Figures 6-8, a fluid extraction device 110 according to a second preferred embodiment of the present invention is shown. The device 110 includes an air injection tube 112 which passes through a fluid recovery tube 114 in a manner similar to the configuration of the preferred embodiment shown in Figure 1 and discussed above.
[0041] The air injection tube 112 is connected to an outlet of an air mover 124, preferably a single-stage fan-type blower, for providing a flow of air through the air injection tube 112. The air mover 124 is preferably operated by a controller which receives instructions from a user operated control panel 148, which can be a simple switch arrangement. A heat source connector 136 is preferably connected to an inlet of the air mover 124 via a scavenge tube 146 which functions as a conduit to transport heated air emitted from an external hot surface 160 onto which the connector 136 is attached, as shown in Figures 6-8. The external hot surface 160 may include a hot engine manifold or other mechanical or electromechanical device which emits significant heat during operation. The connector 136 preferably includes a magnet 138, shown in Figures 7 and 8, to facilitate its attachment to hot surfaces which are ferromagnetic, and a filter to prevent contamination of the extracted fluid. Alternatively, other attachment devices such as clamps, clips and hooks may be used in addition to or in place of the magnet 138. Intake ports 140 are preferably positioned at an end of the connector 136 such that a flow of air (shown by arrows in Figure 8) in created by the air mover 124 passes directly over a heated surface on which the connector is attached to efficiently heat the air flow. A heater 128, operated by the controller, can also be provided for further heating the flow of air produced by the air mover 124, the flow of air preferably having been pre-heated by the external hot surface 160. Alternatively, the heater 128 can be omitted, leaving the flow of air heated only by the external hot surface 160.
[0042] A spout 134 is connected to the fluid recovery tube 114. The spout 134 is preferably sufficiently elongated and narrow to permit its insertion into a fluid filling port of a machine, for example, a motor oil filling port 162 on an internal combustion engine 170. In this manner, the device 110 can be quickly and easily attached and removed from a machine, and fluid extracted from a container such as the container 50 can be directly transferred into the filling port of a machine eliminating the need for additional storage containers. Power can be obtained to operate the device 110 by attaching a connector to a power source of a machine on which the device 110 is placed. For example, if the device 110 is attached to a vehicle engine, power can be obtained by attaching spring loaded conductive clamps directly to the vehicle's battery terminals or connecting an adapter to the vehicle's cigarette lighter. Alternatively, the device 110 can be integrally formed with a machine requiring a periodic addition of fluids from a container.
[0043] Referring to Figures 9-14, a fluid extraction device 210 according to a third preferred embodiment of the present invention is shown. The device 210 includes an air injection tube 212 which passes through a fluid recovery tube 214 connected to a reservoir 230 in a manner similar to the configuration of the preferred embodiment shown in Figure 1 and discussed above.
[0044] The air injection tube 212 is connected to an outlet of an air mover 224, shown in Figure 11, via a first conduit 226. The air mover, preferably a single-stage fan-type blower, is preferably operated by a controller 292, shown in Figure 14, which receives instructions from a user operated control panel 248. A solar heat collector 236 is preferably connected to an inlet of the air mover 224 via a second conduit 246 which transports heated air (shown by arrows in Figure 13) from the collector 236 to the air mover 224. The solar heat collector 236 preferably includes a cavity 240 disposed between generally black colored panels 242 through which air travels to collect heat. Dimples 244 are provided within the cavity to promote turbulence to increases heat transfer between the panels 242 and the air 280. Preferably, a heater 228 is also provided for further heating the air flowing through the first conduit 226. The heater 228 is useful for situations where there is inadequate solar energy to heat the air.
[0045] A photovoltaic collector 254 with an associated storage battery 256 is also preferably provided. The photovoltaic collector 254 produces electrical energy from solar radiation to provide power to the air mover 224 directly, or alternatively, the collector 254 charges the battery 256 which provides the necessary power. Alternatively, the photovoltaic collector 254 can also power the heater 228. The photovoltaic collector 254 and the solar heat collector 236 are preferably angularly adjustable to an angle α, as shown in Figure 12, to allow a maximum amount of solar energy to be received by the collectors 236,254.
[0046] Figure 14 shows a process control diagram depicting the interaction of various sensor components of the fluid extraction device 210 with the controller 292. A first voltage sensor 282 is preferably connected to the photovoltaic collector 254 to determine a voltage output of the collector 254. A second voltage sensor 284 is preferably connected to the battery 256 to determine a battery charge. A temperature sensor 288 such as a resistance thermometer or thermocouple is preferably positioned downstream from the solar heat collector 236. A dimensioning sensor 290 for determining the size of a container, such as a container 50, can also be provided. The sensors 282, 284, 288, 290 as well as a power lead 286 are connected to the controller 292. The controller 292 preferably utilizes information signals provided by the sensors to optimize power output to the air mover 224 and the heater 228. This information can also be used for controlling a motor for adjusting the an angular positioning of the photovoltaic collector 254 and the solar heat collector 236 as shown in Figure 12.
[0047] Referring to Figures 15 and 16, a portion of a fluid extraction device 310 according to a fourth preferred embodiment of the present invention is shown. The device 310 includes a radiant heat element 312 which passes through a fluid recovery tube 314. Radiant heat emitted by the radiant heat element 312 decreases the viscosity of residual fluid within a container such as the container 50 placed over the element 312 allowing the fluid to be retrieved in a manner such as described above with reference to the first, second, or third embodiments of the present invention.
[0048] Alternative embodiments of the present invention may incorporate other systems for decreasing the viscosity of residual fluid in a container. In one alternative embodiment, the air injection tube disposed within the fluid recovery tube as described above with reference to the first, second, or third embodiments of the present invention can be replaced by a single tube which functions to supply heated air and extract residual fluid. In another alternative embodiment, a hot fluid spray tube can replace the air injection tube as described above to allow heated fluid from a reservoir (identical to the fluid being extracted) to be heated and sprayed onto the inner walls of a container using the hot fluid spray tube. In yet another alternative embodiment, a sonic vibrator could be used in place of or in addition to the systems described in the preferred embodiments. By vibrating a container at specific frequencies, such as the natural frequency of a fluid film on the inner walls of the container, the extraction of residual fluid can be accelerated. In yet another alternative embodiment, microwave radiation may be employed to accelerate the extraction of residual fluids.
[0049] Referring to Figure 17, a method 400 for conserving residual fluid from a container having a mouth is provided. The method can be practiced using devices of the preferred embodiments discussed above with reference to Figures 1-16. The method includes generally inverting a container (step 402), wherein generally inverting a container is defined as positioning the mouth of the container at a relatively lower gravitational potential than the end of the container opposite the mouth. The mouth of the container is positioned over a fluid recovery receptacle (step 404) and a medium is introduced through the mouth of the container to decrease the viscosity of residual fluid within the container (step 406). The medium preferably includes heated air. Alternatively, the medium can include radiant heat, hot fluid, microwaves, a vibration inducing member or any suitable medium. Optionally, the method can further include connecting the fluid recovery receptacle to a fluid filling port of a machine, for example, an oil filling port on a motor vehicle.
[0050] While the preferred embodiments of the invention have been described in detail above, the invention is not limited to the specific embodiments described above, which should be considered as merely exemplary. Further modifications and extensions of the present invention may be developed, and all such modifications are deemed to be within the scope of the present invention as defined by the appended claims.
1. A residual fluid extraction device comprising:
an air injection tube for injecting heated air through a mouth of a container; and
a fluid recovery receptacle for receiving fluid from a mouth of a container.
2. The device of claim 1, further comprising a heater connected to the air injection
tube for heating air for injecting through the air injecting tube.
3. The device of claims 1 or 2, wherein the fluid recovery receptacle comprises a fluid
recovery tube, and wherein the air injection tube is located generally concentric
to the fluid recovery tube at a receiving area for a mouth of a container.
4. The device of one or more of claims 1-3, further comprising an air mover connected
to the air injection tube for providing a flow of air through the air injection tube,
and further preferably comprising a heat source for heating the flow of air produced
by the air mover.
5. The device of one or more of claims 1-3, further comprising:
an air mover having an inlet and an outlet, wherein the air injection tube is connected to the air mover at the outlet of the air mover; and
a scavenge tube connected to the inlet of the air mover, the scavenge tube including a connector for connection to a heated surface, wherein preferably the scavenge tube connector includes a magnet for connecting the connector to a ferromagnetic surface.
6. The device of one or more of claims 1-5, wherein the air injection tube is elongated
and extends vertically from a receiving area for a mouth of a container; and/or
wherein the air injection tube extends from within the fluid recovery receptacle; and/or
wherein the fluid recovery receptacle is adapted to receive a mouth of a container therein.
wherein the air injection tube extends from within the fluid recovery receptacle; and/or
wherein the fluid recovery receptacle is adapted to receive a mouth of a container therein.
7. The device of one or more of claims 1-6, further comprising a discharge spout connected
to an end of the fluid recovery receptacle for discharging from the device fluid received
from a mouth of a container; and/or
further comprising a dust cap removably attached over the air injection tube and fluid recovery receptacle; and/or
further comprising an omni-directional nozzle connected to an end of the air injection tube, the nozzle including a plurality of flow paths for distributing a flow of air exiting the air injection tube.
further comprising a dust cap removably attached over the air injection tube and fluid recovery receptacle; and/or
further comprising an omni-directional nozzle connected to an end of the air injection tube, the nozzle including a plurality of flow paths for distributing a flow of air exiting the air injection tube.
8. The device of one or more of claims 1-7, further comprising:
a solar collector for absorbing heat energy; and
a conduit which connects the air injection tube to the solar collector for transporting heated air from the solar collector to the air injection tube.
9. The device of claim 1, further comprising:
an air mover having an inlet and an outlet, wherein the air injection tube is connected to the air mover outlet;
a photovoltaic solar collector connected to the air mover for supplying current to the air mover; and
a conduit connected to an inlet of the air mover for providing the heated air to the air injection tube.
10. The device of claim 8, third alternative, wherein the flow paths are configured to
direct a flow of air in a horizontal direction, generally perpendicular to the air
injection tube.
11. The device of claim 1, wherein the air injection tube comprises a plurality of air
injection tubes connected to a manifold that distributes heated air to each of the
air injection tubes, and the fluid recovery receptacle comprises a plurality of fluid
recovery receptacles connected to a common reservoir for receiving fluid received
from the plurality of fluid recovery receptacles.
12. A residual fluid extraction device comprising:
means for decreasing the viscosity of fluid adapted for insertion into a mouth of a container; and
a fluid recovery receptacle for receiving fluid from the mouth of a container.
13. A method for conserving residual fluid from a container having a mouth, the method
comprising:
generally inverting the container;
positioning a mouth of the container over a fluid recovery receptacle; and
introducing a medium through the mouth of the container for decreasing the viscosity of the residual fluid.
14. The method of claim 13, wherein the introducing the medium comprises inserting an
air injection tube into the mouth of the container and injecting heated air into the
container using the air injection tube; and/or
wherein the introducing the medium comprises inserting a radiant heater into the mouth of the container and heating the container using the radiant heater; and/or
further comprising removably connecting the fluid recovery receptacle to a fluid filing port on a machine.
wherein the introducing the medium comprises inserting a radiant heater into the mouth of the container and heating the container using the radiant heater; and/or
further comprising removably connecting the fluid recovery receptacle to a fluid filing port on a machine.