Compact water filtration pump

• US 5,534,145 A
• Filed: 08/15/1994
• Issued: 07/09/1996
• Est. Priority Date: 04/09/1991
• Status: Expired due to Term

• Current Assignee: Cascade Designs Inc
• Original Assignee: SweetWater, Inc. (Cascade Designs Inc)
• Inventors: Kraemer, Richard J., Platter, Sanford, Aldred, Jeffrey K.
• Primary Examiner(s): Nessler, Cynthia L.
• Application Number:
  US08/290,688
• Time in Patent Office: 694 Days
• Field of Search: 210/767, 210/416.3, 210/416.1, 210/416.2, 210/416.4, 210/416.5, 210/232, 210/237, 210/238, 210/282, 210/541, 210/542, 210/266, 210/440-443, 210/448 , 210/449, 210/452, 210/459, 210/460, 210/462, 210/463, 210/469, 210/473, 210/474, 210/90, 210/130, 417/544, 417/238, 417/319, 417/234, 285/13, 285/14
• US Class Current: 210/90
• CPC Class Codes: B01D 35/26 Filters with built-in pumps filters provided with a pump mounted in or on the casing aquarium pumps or filters A01K63/04
• CPC Class Codes: B01J 47/024 where the ion-exchangers are in a removable cartridge
• CPC Class Codes: C02F 1/002 using small portable filters for producing potable water, e.g. personal travel or emergency equipment, survival kits, combat gear C02F1/003 takes precedence
• CPC Class Codes: C02F 1/003 using household-type filters for producing potable water, e.g. pitchers, bottles, faucet mounted devices C02F9/20 takes precedence
• CPC Class Codes: C02F 1/283 using coal, charred products, or inorganic mixtures containing them
• CPC Class Codes: C02F 1/50 by addition or application of a germicide or by oligodynamic treatment C02F1/4606, C02F1/467, C02F1/76 take precedence
• CPC Class Codes: C02F 2201/006 Cartridges
• CPC Class Codes: F04B 53/123 Flexible valves
• CPC Class Codes: F04B 9/14 Pumps characterised by muscle-power operation hand-held spraying or dispensing apparatus using pumps or bulbs B05B11/00

Abstract

A portable, manually-operated water filtration pump for purifying water. The pump includes an inexpensive, disposable filter cartridge which can be easily changed when the filter elements are no longer effective. The pump uses a lever to actuate a double-acting piston. The lever is collapsible to one side of the pump for compact storage. The filter cartridge is a tubular cylinder having an inner bore forming the pump cylinder. A cylindrical mechanical filter is concentric with and adjacent to the inner bore to filter out particulates larger than 0.3 microns. A fluidized granual activated carbon filter surrounds the mechanical filter to absorb halogen and halogen-related compounds such as herbicides and pesticides. The pump pumps filtered water into a bottle adaptor which will fit most standard water containers. A prefilter is provided to screen out large particulates from the pump to enhance the life of the filter elements. The prefilter is shaped such that it will sink in water sources and to keep the prefilter inlet substantially upright in still water and tilted from horizontal in moving water.

Claims

1. A pump for fluid filtration, said pump comprising:

a housing;

a piston rod slidably mounted on said housing for movement along a first axis of said housing;

a piston affixed to a lower end of said piston rod;

elongated lever means having one end pivotably attached to an upper portion of said housing and attachable at an intermediate location of said lever means to a cross head on an upper end of said piston rod for slidably moving said piston along said first axis of said housing when said lever means is pivoted;

a pump cylinder having an upper end mounted to said housing for enabling said piston to slide within a circular inner bore of said cylinder;

a lower end of said cylinder having inlet means for enabling fluid to enter said inner bore of said cylinder when said piston moves away from said inlet means;

a replaceable filter cartridge;

connector means for removably engaging said replaceable filter cartridge with said housing, said replaceable filter cartridge including;

cylindrical filtering means concentric with and surrounding said pump cylinder;

an inner plenum formed between an upper end portion of said pump cylinder and said filtering means for enabling a substantially uniform, laminar flow of unfiltered fluid to be pumped from said inner bore and through said inner plenum and through said filtering means when said piston moves within said inner bore; and

baffle means abutting said cylindrical filtering means and adjacent said inner plenum at an upper end of said inner bore for directing said substantially uniform flow of fluid pumped from said inlet means and through said inner bore into said inner plenum and through said filtering means; and

outlet means disposed at an upper end of said cartridge for enabling said fluid to exit said filter cartridge after said fluid is pumped through said filtering means at said substantially uniform flow.

2. The pump of claim 1 wherein said pump further comprises:

means on said piston for providing a double-acting piston to provide uniform fluid flow through said pump when said piston slides within said inner bore; and

said inner bore has an inner volume equal to twice the volume of said piston rod of said pump so that the volume of fluid displaced when said piston moves away from said inlet means in said inner bore is substantially equal to the volume of fluid displaced when said piston moves toward said inlet means in said inner bore to provide uniform flow through said pump.

3. The pump of claim 1 wherein said lever means is movable from a compact storage position in which it is folded about said one end of said lever means against said housing and disengaged from said piston rod to a pumping position in which said intermediate location of said lever means engages said piston rod to move said piston within said inner bore at a mechanical advantage when said lever means is pivoted.

4. The pump of claim 1 wherein said pump further comprises:

an adaptor means connected to said outlet means for closely fitting the openings of water containers.

5. The pump of claim 1 wherein the width of said inner plenum is proportional to the flow rate of the fluid through said inner plenum end to the effective length of said inner plenum and to the total wetted perimeter of said inner plenum.

6. The pump of claim 1 wherein said pump further comprises adapter means connectable to said outlet means for interfering engagement with an opening of a container;

wherein said adapter means includes;

a cylindrical member having a connector connectable via a nose with said outlet means;

a vent hole adjacent to said connector to allow air to leave said vent hole as it is filled with fluid from said pump;

a plurality of concentric ring-shaped members of differing diameters formed on a surface of said cylindrical member wherein each of said plurality of concentric ring-shaped members has a diameter to interferingly engage a different size opening of a container.

7. The pump of claim 1 wherein said pump further comprises:

a spring loaded pressure relief valve positioned within said inner bore and within said piston rod, said pressure relief valve defining means for enabling fluid to flow past said pressure relief valve, upwards through the interior of said piston rod and out of said pump when the fluid pressure within said inner bore exceeds a predetermined magnitude.

8. The pump of claim 1 wherein said inner plenum is formed between said inner bore and said filtering means for providing minimum pressure drop through said pump;

and wherein

said outlet means includes an outer plenum formed adjacent an exit area of said filtering means for providing a low pressured drop through said pump and a substantially uniform flow of fluid out of said pump.

9. The filter cartridge of claim 8 wherein the dimensions of said inner plenum are chosen for uniform flow through said plenum according to the following ratio:

##EQU3## wherein;

R_N =a dimension-less number ranging between 500 and 1500;

N=kinnematic viscosity of the fluid;

Q=volumetric flow rate through said inner plenum;

L_p =effective length of said inner plenum;

P_eff =effective wetted perimeter of said inner plenum;

P_eff =π

(D_p +D_f); and

D_f =inner diameter of said filtering means adjacent said inner plenum; and

D_p =inner plenum diameter.

10. The pump of claim 1 wherein said baffle means is formed at an entrance of said inner plenum for preventing high velocity fluid jet flow into said inner plenum and for providing laminar flow into said inner plenum.

11. The pump of claim 10 wherein said baffle means include a non-erodible surface formed in said baffle means to direct the fluid flow from said piston parallel to said filtering means.

12. The pump of claim 1 wherein said filtering means include:

a rigid, cylindrical, tubular mechanical filter means concentric with and surrounding said inner plenum for removing particulate contamination; and

a cylindrical granular activated carbon filter means concentric with and surrounding said mechanical filter means for absorbing chlorine and chlorine compounds.

13. The pump of claim 12 wherein said mechanical filter means filters particulate not less than 0.1 micron.

14. The pump of claim 1 wherein said pump further includes:

sealing means on the outer periphery of said piston for providing a double-acting piston;

said sealing means including means for enabling only the one way flow of fluid past said piston and said sealing means as said piston is moved to pump said fluid.

15. The pump of claim 14 wherein sealing means on said piston defines means for preventing fluid flow past said sealing means during the movement of said piston away from said inlet means and enables fluid to flow past said sealing means during the movement of said piston toward said inlet means;

and

said inlet means includes inlet valve means for enabling fluid to enter said inner bore during the movement of said piston away from said inlet means and preventing fluid from exiting said inlet means during the movement of said piston towards said inlet means.

16. The pump of claim 14 wherein said sealing means include a seal having a flexible outer lip, said flexible outer lip defining means for preventing toward an inner surface of said inner bore during the movement of said piston away from said inlet means to prevent fluid flow past said piston during the movement of said piston away from said inlet means, and for moving away from said surface of said inner bore during the movement of said piston towards said Inlet means to allow fluid flow past said piston during the movement of said piston towards said inlet means.