U.S. patent application number 14/642557 was filed with the patent office on 2016-09-15 for bottom draw pump.
This patent application is currently assigned to IP HOLDINGS, LLC. The applicant listed for this patent is Rod Davis. Invention is credited to Rod Davis.
Application Number | 20160265536 14/642557 |
Document ID | / |
Family ID | 56887522 |
Filed Date | 2016-09-15 |
United States Patent
Application |
20160265536 |
Kind Code |
A1 |
Davis; Rod |
September 15, 2016 |
BOTTOM DRAW PUMP
Abstract
A submersible bottom draw pump having prefilter screen and
impeller intake structure oriented at the bottom surfaces of the
pump so as to minimize the required depth within which the pump
operates, and having integral horizontal and vertical outlets so as
to provide a submersible bottom draw pump that may be selectably
configured as either a horizontal outlet bottom draw pump or a
vertical outlet bottom draw pump.
Inventors: |
Davis; Rod; (Vancouver,
WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Davis; Rod |
Vancouver |
WA |
US |
|
|
Assignee: |
IP HOLDINGS, LLC
Vancouver
VA
|
Family ID: |
56887522 |
Appl. No.: |
14/642557 |
Filed: |
March 9, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04D 13/08 20130101;
F04D 29/4293 20130101; F05D 2250/52 20130101 |
International
Class: |
F04D 13/06 20060101
F04D013/06; F04D 29/40 20060101 F04D029/40 |
Claims
1. A method of drawing and pumping fluid in a reservoir or
container comprising: (a) filling a space between a prefilter
screen and fins of an impeller of a pump with a fluid to be moved
by the impeller; (b) filling a space surrounding at least a portion
of the axial width of the impeller's fins with the fluid so that
rotation of the impeller fins causes the fins to contact and move
the fluid; (c) drawing the fluid comprising water or nutrient
infused liquid or other liquid solution through the prefilter
screen and into the fins of the rotating impeller; (d) accelerating
the fluid radially across the fins of the impeller causing the
fluid to flow radially outward away from the rotational axis of the
impeller in a direction perpendicular to the impeller axis; and (e)
the fluid then caused to selectably flow in either one of two
selectable directions, the selectable directions comprising a first
direction through an outlet fitting affixed to a first outlet
integral to the pump housing, or, alternatively and convertibly by
way of moving a plug from a second outlet integral to the pump
housing to the first outlet and moving the outlet fitting from the
first outlet to the second outlet, a second direction through the
outlet fitting affixed to the second outlet.
2. The method of claim 1 further comprising placing the pump on the
bottom of the reservoir or container so that the prefilter is
between the bottom of the reservoir and the pump impeller fins, and
so that the impeller axis of rotation is substantially
perpendicular to the bottom of the reservoir.
3. The method of claim 2 wherein pumping fluid from the first
outlet comprises pumping fluid in a first direction that is
substantially horizontal and perpendicular to the impeller axis,
and wherein pumping fluid from the second outlet comprises pumping
fluid in a second direction that is substantially vertical and
parallel to the impeller axis.
4. The method of claim 2 wherein the pump is operable in fluid
having no more depth than enough to fill the space between the
bottom of the reservoir upon which the pump rests and the space
surrounding enough of the axial width of the impeller's fins so
that rotation of the impeller fins causes the fins to contact and
move the fluid one of the two selectable directions.
5. A convertible submersible bottom draw pump capable of performing
the method of claim 1.
6. The pump in claim 5 further capable of performing the method of
claim 2.
7. The pump in claim 5 further capable of performing the method of
claim 3.
8. The pump in claim 5 further capable of performing the method of
claim 4.
9. A bottom draw pump comprising: (a) a unitary motor housing
having sealed therewithin an electric motor for rotating an
impeller; (b) impeller fins of the impeller extending radially
outward from an impeller axis and having an axial width, the
impeller axis oriented substantially perpendicular to a bottom
surface of the bottom draw pump with the impeller fins; (c) an
impeller cover retaining the impeller within the motor assembly and
having an aperture forming an intake into which fluid is drawn in
an axial direction into the rotating impeller fins and accelerated
radially outward along the impeller fins in a direction
perpendicular to the impeller axis; (d) a prefilter screen covering
the impeller cover and forming at least a portion of the bottom
surface of the bottom draw pump; (e) a first outlet integral to the
motor housing oriented to direct fluid drawn axially into the
impeller fins and then accelerated by the impeller fins in a
direction substantially perpendicular to the impeller axis; (f) a
second outlet integral to the motor housing oriented to direct
fluid drawn axially into the impeller fins and then accelerated by
the impeller fins in a direction substantially parallel to the
impeller axis; (g) a plug selectably and repeatably fastenable in
either the first outlet or the second outlet to prevent fluid flow
from the plugged outlet; and (h) an outlet fitting selectably and
repeatably fastenable in either the second outlet or the first
outlet to allow fluid flow from the unplugged outlet.
10. The pump of claim 9 wherein when the outlet fitting is fastened
in the first outlet and the plug is fastened in the second outlet
the first outlet is substantially parallel to the bottom surface of
the bottom draw pump.
11. The pump of claim 9 wherein when the outlet fitting is fastened
in the second outlet and the plug is fastened in the first outlet
the second outlet is substantially perpendicular to the bottom
surface of the bottom draw pump.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] None.
TECHNICAL FIELD OF THE INVENTION
[0002] This invention relates generally to a bottom draw pump
ideally for use in hydroponic or indoor gardening applications,
and, more particularly, to improved methods and apparatuses for a
submersible bottom draw pump capable of operation in very shallow
depths.
BACKGROUND OF THE INVENTION
[0003] Submersible pumps for hydroponic or indoor gardening
applications have heretofore been configured with a motor housing
having a water intake that is perpendicular to a water outlet, with
the intake most commonly in a horizontal orientation and the outlet
in a vertical orientation so that the pump rests on a bottom
surface, draws water in from a horizontal (parallel) orientation to
the bottom surface, and pumps water upward out through the upward
facing, or vertical, outlet. Such pumps are commonly configured
with a substantially unitary rectangular housing with an electrical
cord extending from the housing, and the housing having one fixed
position intake and one fixed position outlet. The pumps are simple
devices using an impeller to draw water into a substantially
cylindrical intake tube, centrifugally accelerate the water across
fins comprising the impeller, and expel the water into a
substantially cylindrical outlet tube oriented perpendicular to the
intake tube and out of the unitary housing through the outlet.
[0004] Submersible pumps are used for a variety of hydroponic and
indoor gardening applications. For example, a compost tea brewing
system such as the Flow-n-Brew system part no. 702800 from Sunlight
Supply, Inc., includes a submersible pump for drawing tea
components into a fountain head to circulate and agitate the tea.
Another example is a hydroponic gardening bucket system such as the
Flo-n-Gro ebb and flow system part no. 702806 from Sunlight Supply,
Inc., which comprises two submersible pumps--one pump for filling
flood lines and connected planter buckets, and another for draining
from the flood lines and connected planter buckets.
[0005] Existing submersible pumps are limited to drawing water from
depths of several inches and are generally limited in the
orientation of the pump intake and outlet. That is, existing pumps
generally need several inches of depth in order to work properly,
with the pump unit sitting on the bottom surface of the water
source within several inches of water, and have an intake
cylindrical tube that is perpendicular to an outlet tube. Such
pumps are unable to operate with less water because of the height
of the pump intake, the geometries associated with the intake tube,
dynamics associated with priming (and maintaining priming) and
maintaining sufficient pressures for the pump to operate, and other
factors. Such pumps require external components to be clamped onto
the intake and outlet tubes in order to redirect flow lines to
and/or from such pumps, further limiting the versatility of the
pumps and the dimensions and conditions within which the pumps may
be used.
[0006] What is needed are new and innovative designs for a
submersible pump that offer improvements in cost, quality,
delivery, performance, and/or feature content over existing
submersible pumps. What is need are new and innovative methods and
apparatuses for a bottom draw pump capable of operation in very
shallow depths, and for a bottom draw pump especially suitable for
hydroponic and indoor gardening applications.
[0007] The foregoing and other objectives, features, and advantages
of the invention will be more readily understood upon consideration
of the following detailed description of the invention taken in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION THE DRAWINGS
[0008] Elements in the figures have not necessarily been drawn to
scale in order to enhance their clarity and improve understanding
of these various elements and embodiments of the invention.
Furthermore, elements that are known to be common and well
understood to those in the industry such as electrical power
connection are not necessarily depicted in order to provide a clear
view of the various embodiments of the invention, thus the drawings
are generalized in form in the interest of clarity and
conciseness.
[0009] FIG. 1 shows a perspective view of a submersible pump, as
viewed from the front, according to one embodiment, with a
prefilter, a plug, and an outlet fitting shown pulled away from the
rest of the pump assembly and with the plug and outlet fitting
oriented in a first outlet orientation.
[0010] FIG. 2 shows a perspective view of a submersible pump, as
viewed from the rear, according to one embodiment, with a
prefilter, a plug, and an outlet fitting shown pulled away from the
rest of the pump assembly and with the plug and outlet fitting
oriented in a first outlet orientation.
[0011] FIG. 3 shows a perspective view of a submersible pump, as
viewed from the top, according to one embodiment, with a prefilter,
a plug, and an outlet fitting shown pulled away from the rest of
the pump assembly and with the plug and outlet fitting oriented in
a second outlet orientation.
[0012] FIG. 4 shows a side view of a submersible pump, according to
one embodiment, with a prefilter, a plug, and an outlet fitting
shown pulled away from the rest of the pump assembly and with the
plug and outlet fitting oriented in a second outlet
orientation.
[0013] FIG. 5 shows a bottom view of a submersible pump, according
to one embodiment, with an outlet fitting pulled away from the rest
of the pump assembly and in a first outlet orientation.
[0014] FIG. 6 shows a diagram of an alternative embodiment of a
submersible pump outlet tube with a valve in a horizontal outlet
tube position.
[0015] FIG. 7 shows a diagram of an alternative embodiment of a
submersible pump outlet tube with a valve in a vertical outlet tube
position.
[0016] FIG. 8 shows an exploded perspective view of a submersible
pump, as viewed from the front and bottom, with a plug oriented in
a first outlet orientation.
DETAILED DESCRIPTION THE DRAWINGS
[0017] Although preferred embodiments are described in the context
of a submersible bottom draw pump having a substantially
rectangular shaped housing with convertible outlets, one directed
on a side of the housing perpendicular to the axial rotation of an
impeller and the other directed on a side of the housing opposite
to the side into which fluid flows into the intake, and having a
prefilter screen substantially covering the entire same side as the
intake, separable inventive aspects in various embodiments are
disclosed. The overall shape of the housing may be other than
rectangular in some embodiments. Other embodiments may comprise a
prefilter covering less than the entire intake side of the housing
yet still comprise inlets and an orientation and distribution of
inlets as illustrated and described. Various embodiments may employ
materials different than the molded plastic structures comprising
the housing, prefilter, plug, fitting, and other components.
[0018] In preferred embodiments, a method of drawing and pumping
fluid from the bottom of a reservoir or container comprises filling
or priming a space between a prefilter screen and the fins of an
impeller with a fluid to be moved through an impeller of a pump,
further filling or priming at least a portion of the axial width of
the impeller's blades so that rotation of the impeller blades
causes the fins or blades to contact and move the fluid, and
drawing fluid such as water or nutrient infused or other liquid
solution through a prefilter screen, into the fins of a rotating
impeller, accelerating the fluid across the fins of the impeller
causing the fluid to flow outward away from the rotational axis of
the impeller in a direction perpendicular to the impeller axis, the
fluid then caused to flow horizontally through an outlet fitting
affixed to a horizontal outlet of the pump housing or,
alternatively and convertibly by way of moving a plug from a
vertical outlet of the pump housing to the horizontal outlet and
moving the outlet fitting from the horizontal outlet to the
vertical outlet, caused to flow vertically through the outlet
fitting affixed to the vertical outlet.
[0019] FIG. 1 shows a perspective view of a submersible or bottom
draw pump 100, as viewed from the front, according to one
embodiment, with a prefilter 104, a plug 132, and an outlet fitting
128 shown pulled away from the rest of the pump or motor assembly
102 and with the plug and outlet fitting oriented in a first
(horizontal) outlet orientation. In a horizontal outlet
orientation, according to one embodiment, the outlet fitting 128
may be fastened to the horizontal outlet 136 via threads on the
outlet fitting 128 and cooperatively mating threads 134 on the
horizontal outlet 136, whether male or female threads on either the
outlet fitting 128 or horizontal outlet 136. An outlet plug 132 may
be threadably fastened to a vertical outlet (not shown in FIG. 1)
via threads 138 on the outlet plug 132 and cooperatively mating
threads on the vertical outlet. Preferrably the threads 138 on the
outlet plug 132 and outlet fitting 128 allow for either the plug
132 or the outlet fitting 128 to be threadably fastened to either
the horizontal outlet 136 or the vertical outlet.
[0020] As shown in FIG. 1, a prefilter 104 may comprise a bottom
screen cap having side intake holes such as side intake hole 124 on
side 140, rear intake holes such as rear intake hole 122, and
bottom intake holes such as bottom intake holes 118 and 120 on
prefilter bottom surface 126. The prefilter 104 may comprise pads
or suction cups 116 as shown, on the bottom surface 126 for
providing a gap between the bottom surface intake holes and a
bottom surface upon which the submersible pump 100 rests. The
prefilter 104 preferably covers the entire bottom surface of the
pump or motor assembly 102, and comprises sides such as side 140
that fastenably engage with a lower perimeter of the pump housing
102. The prefilter 104 preferably comprises a cutout 114 at a
horizontal outlet 136 end to allow for the prefilter to fit more
closely to the perimeter of the motor assembly housing 102,
preferably allowing for a reduced gap between the the prefilter 104
surfaces and structures on the bottom of the pump assembly 102.
[0021] Structures on the bottom surfaces of the pump or motor
assembly 102, in preferred embodiments, comprise an impeller
retainer or cover 106 with its center structure 110 for retaining a
lower end of the impeller axis. The impeller retainer 106
preferably includes some cross members as shown to provide
additional filtering of material from flowing into and fouling the
impeller fins 108, and the impeller retainer 106 preferably
includes threads or a latch or fasteners or (as shown) features for
rotating the impeller retainer 106 to remove it to expose the
impeller assembly and interior of the outlet tube 112 therewithin
for removal of debris or for cleaning or maintenance. The impeller
retainer 106 preferably comprises a circular opening centered about
the impeller axis and having a radius less than the radial length
of the impeller fins (or blades) 108. A smaller radius opening in
the impeller retainer 106 (i.e. a smaller radius as compared to the
radius of impeller fins 108) allows for fluid to be pumped to move
into the fins 108 of the impeller closer to the axis of rotation,
with rotation of the fins causing the fluid to accelerate radially
outward from the axis of rotation and into outlet tube 112.
[0022] In preferred embodiments, with the prefilter 104 engaged
with the motor assembly 102, the outlet fitting 128 threadably
fastened into the horizontal outlet 134, and the outlet plug 132
threadably fastened into the vertical outlet, the bottom draw pump
(in an horizontal outlet configuration) 100 provides a convertible
bottom draw submersible pump. The assembled pump 100 may be
positioned to rest on pads 116 at the bottom of a reservoir, or
using suction pads 116 to keep the pump in as desired location, for
drawing fluid through the prefilter 104, into the rotating impeller
fins 108, through outlet tube 112 and horizontal outlet 136.
[0023] An exemplary convertible bottom draw pump, according to a
preferred embodiment, comprises the bottom draw pump substantially
as shown in FIG. 1 and is distributed by Sunlight Supply, Inc. as a
model 727810 pump that operates at an electrical input of (nominal)
120 volts/60 Hz, with a rating of 75 W and 1.2 Ampheres current
draw, for pumping 730 GPH (rating), and with a maximum head of 10.8
feet. This particular model includes additional outlet fittings to
accommodate different diameters of tubing--i.e. a dual diameter 1''
& 11/4'' fitting, a 3/4'' fitting, a 1/2'' fitting, and a GHT
fitting for attaching a standard garden hose--and is advertised to
work in depths as low as 13/16'' (i.e. 13/16 inch).
[0024] FIG. 2 shows a perspective view of a submersible pump 200,
as viewed from the rear, according to one embodiment, with a
prefilter 104, an outlet plug 132, and an outlet fitting 128 shown
pulled away from the rest of the pump assembly and with the plug
132 and outlet fitting 128 oriented in a first (horizontal) outlet
orientation. As described, a prefilter 104 preferably comprises
rear side holes such as rear side hole 250 and side holes such as
side hole 224 along side 240, in addition to multiple bottom
surface holes such as bottom surface hole 118. The outlet fitting
128 preferably comprises anchors 252 (also shown in FIG. 1) and
enough length for use of a pipe clamp for attaching tubing to the
outward end of the outlet fitting 128. The outlet fitting 128 may
also comprise a seal 258. In operation (with the prefilter 104,
plug 132, and outlet fitting 128 assembled to the motor assembly
102 and configured as shown in FIG. 2), water drawn into the
impeller and outlet tube 112 is directed outward 256 from the
horizontal outlet 136, through the outlet fitting 128, and outward
254 from the outlet fitting 128.
[0025] FIG. 3 shows a perspective view of a submersible pump 300,
as viewed from the top, according to one embodiment, with a
prefilter 104, a plug 132, and an outlet fitting 128 shown pulled
away from the rest of the pump assembly 102 and with the plug 132
and outlet fitting 128 oriented in a second (vertical) outlet
orientation. In one embodiment, the top surface of the motor
housing 102 comprises electrical cord access 372 where an
electrical cord (not shown) extends away from the motor housing
102. The top surface of the motor housing 102 preferably comprises
a vertical outlet 370 for attachment of either an outlet fitting
128 to configure the pump to have a vertical outlet or an outlet
plug 132 to configure the pump to have a horizontal outlet. The
pump 300 as shown, and when the prefilter 104, plug 132, and outlet
fitting 128 are assembled to the motor housing 102, is configured
to have a vertical outlet, with fluid being drawn upward through
the prefilter 104 (shown with its inside surface 374) and allowed
to flow through the tube 112 (not shown) and upward through
vertical outlet 370 and outlet fitting 128, before exiting the pump
assembly 300 through the outward end of the outlet fitting 128. The
pump or motor assembly, or pump or motor housing, 300, when
configured as shown to provide a vertical outlet, provides within a
unitary and integral assembly a vertically oriented impeller axis
(thereby providing an intake that is vertically directed) and a
vertically oriented outlet whereby fluid is drawn into the pump
assembly in a direction substantially parallel with the fluid
pumped out of the pump assembly, without any externally applied
attachments to change the direction of fluid flow. In preferred
embodiments, pump or motor assembly 102 integrally comprises a
vertically oriented impeller axis (thereby providing an intake that
is vertically directed) and a vertically oriented outlet 370 as
well as a horizontally oriented outlet 136.
[0026] In preferred embodiments, converting pump or motor assembly
102 from a horizontal outlet bottom draw pump to a vertical outlet
bottom draw pump comprises unfastening a plug 132 from a vertical
outlet 370, unfastening an outlet fitting 128 from a horizontal
outlet 136, fastening the plug 132 to the horizontal outlet 136,
and fastening the outlet fitting 128 to the vertical outlet 370.
The resulting pump configuration is the vertical outlet pump 300
shown in FIG. 3. Reversing these steps, i.e. converting pump or
motor assembly 102 from a vertical outlet bottom draw pump to a
horizontal outlet bottom draw pump by unfastening a plug 132 from a
horizontal outlet 136, unfastening an outlet fitting 128 from a
vertical outlet 370, fastening the plug 132 to the vertical outlet
370, and fastening the outlet fitting 128 to the horizontal outlet
136, results in a horizontal pump configuration as shown in FIGS. 1
and 2.
[0027] Numerous advantages of various embodiments of a convertible
bottom draw submersible pump as described herein over prior pump
designs include fewer components needed to achieve the
functionality of a horizontal or vertical outlet pump, improved
efficiencies by integrating horizontal and vertical outlets within
a unitary and integral pump housing 102, providing a reconfigurable
pump having an intake at the lowest possible position of the bottom
surfaces of the pump assembly (as shown in FIG. 3), providing a
bottom draw pump capable of vertically drawing water in and
vertically pumping it out through a vertical outlet, providing a
bottom draw pump capable of vertically drawing water in and
convertibly either vertically pumping it out through a vertical
outlet or horizontally pumping it out through a horizontal outlet
depending on fastening a plug in one or the other of a horizontal
outlet or a vertical outlet, and providing a bottom draw pump that
requires only a fluid depth (measured in a direction along the
pump's impeller axis) enough to cover the pumps horizontally
oriented impeller intake and enough of the impeller fins for the
impeller fins to accelerate the fluid though the pump's outlet tube
112, among other advantages.
[0028] FIG. 4 shows a side view of a submersible pump 400,
according to one embodiment, with a prefilter 104, a plug 132, and
an outlet fitting 128 shown pulled away from the rest of the pump
assembly and with the plug 132 and outlet fitting 128 oriented in a
second (vertical) outlet orientation. As shown, fluid is drawn
vertically 480 into the impeller intake and directed through the
pump housing 102 and pumped out vertically 486 through vertical
outlet 370. The outlet fitting 128 may comprise a hexagonal nut 482
for tightening threads 484 of the outlet fitting 128 into
corresponding threads of the vertical outlet 370.
[0029] FIG. 5 shows a bottom view of a submersible pump 500,
according to one embodiment, with an outlet fitting 128 pulled away
from the rest of the pump assembly and in a first (horizontal)
outlet orientation. Multiple holes 590 comprise the prefilter 104,
in preferred embodiments.
[0030] FIG. 6 shows a diagram of an alternative embodiment of a
submersible pump convertible outlet tube design 600 with a valve
609 in a horizontal outlet tube position. In one embodiment, outlet
tube 112 comprises a horizontal tube portion 617 allowing pumped
fluid to flow 607 through the open portion 613 of a valve 609 and
to flow 605 through a horizontal tube portion 619 toward horizontal
outlet 136. The blocking portion 611 of the valve 609 blocks fluid
from flowing within the pathway 615 of a vertical outlet tube 603.
In one embodiment, the valve 609 may be rotated to and from its
open (horizontal outlet) position as shown in FIG. 6 by rotating a
knob extending outward from the side of the pump or motor housing
(not shown). Advantages of such a convertible outlet tube design
600 include using the blocking portion 611 of the valve 609 in
place of a plug fastened to the blocked outlet. Disadvantages of
such design include a potential for the valve 609 to be positioned
so as to only partially block flow into the vertical outlet path
615.
[0031] FIG. 7 shows a diagram of an alternative embodiment of a
submersible pump convertible outlet tube design 700 with a valve
609 in a vertical outlet tube position. In one embodiment, outlet
tube 112 comprises a horizontal tube portion 617 allowing pumped
fluid to flow 607 through the open portion 613 of a valve 609 and
to flow 751 through a vertical tube portion 603 toward vertical
outlet 370. The blocking portion 611 of the valve 609 blocks fluid
from flowing within a horizontal outlet tube portion 619. In one
embodiment, the valve 609 may be rotated to and from its open
(vertical outlet) position as shown in FIG. 7 by rotating a knob
extending outward from the side of the pump or motor housing (not
shown).
[0032] FIG. 8 shows an exploded perspective view of a submersible
pump 800, as viewed from the front and bottom, with a plug 132
oriented in a first (horizontal) outlet orientation. In preferred
embodiments, motor assembly 102 comprises an impeller assembly 802
that rotates about a shaft 804 (defining an axis of impeller
rotation) captured at each end by shaft bushings 806, with the
shaft 804 stopped at one end within the motor assembly 102 and
retained at the other end (the intake end) by an impeller cover
106. The shaft 804 may comprise a ceramic shaft so as to avoid
interfering with magnets for driving rotation of the impeller
assembly 802. The shaft 804 defines an axis of rotation of the
impeller assembly, about which the fins 108 of the impeller
assembly rotate, causing fluid to accelerate as the fluid moves
outward across each of the fins 108 away from the shaft 804. The
shaft 804, in preferred embodiments, is substantially parallel to
both the direction of fluid pulled into the impeller cover 106 and
fluid pumped through the vertical outlet 370 (when configured as a
vertical outlet pump), and is substantially perpendicular to both
the direction of fluid pulled into the impeller cover 106 and fluid
pumped through the horizontal outlet 136 (when configured as a
horizontal outlet pump).
[0033] The leading edges of the fins 108 comprising the impeller
assembly 802 define a plane that is perpendicular to the axis of
rotation and shaft 804. The trailing edges of the fins 108
comprising the impeller assembly 802 define a plane that is
perpendicular to the axis of rotation and shaft 804. The leading
edges of the fins 108 are closer to the bottom surfaces (toward the
prefilter 104) of the pump assembly 102, and the difference between
the leading edges and the trailing edges (or the two planes defined
thereby) define a width of the fins 108, with the length of fins
108 being the orthogonal dimension to the width, from the axis of
rotation (or the shaft 804) to the radially outward edges of the
fins 108. As water or fluid moves across the length of a fin 108 it
accelerates and moves radially away from the axis of rotation of
the shaft 804, and allowed or directed to flow into outlet tube
112, which receives flowing water or fluid coming from the impeller
fins 108 in a direction perpendicular to the axis of rotation (i.e.
perpendicular to shaft 804).
[0034] In preferred embodiments, the described convertible
submersible bottom draw pump 800 operates effectively in water or
fluid depth as low as the distance between the lowest contacting
surfaces of a prefilter assembly 104 (with its pads or suction cups
116) and enough of at least a portion of the impeller fin 108 width
needed to accelerate the water or fluid across the impeller fins
108 to cause the fluid to flow through an outlet tube 112. In
preferred embodiments, immersing enough of the width of impeller
fins 108 in the water or fluid to be pumped is referred to as
priming, and priming the pump may comprise filling the reservoir or
container within which water or fluid it to be pumped to a depth
sufficient to immerse enough of the impeller fins 108 such that
rotation of the impeller fins 108 causes the water or fluid to move
radially outward along the impeller fins 108 and perpendicular to
the axis of impeller rotation (i.e. shaft 804) and into outlet tube
112.
[0035] In one embodiment, each impeller blade 108 is approximately
1/4 inch in width. In one embodiment, a convertible submersible
bottom draw pump 800 operates effectively in water or fluid at
least 1/2 inch in depth. In one embodiment, the distance between a
compressed suction cup 116 (compressed when the pump assembly 800
is resting on the bottom surface of a reservoir or container within
which water or fluid is to be pumped by the pump assembly 800) and
enough of the width of the impeller fins 108 to accelerate the
fluid for effective operation of the pump assembly 800, is
approximately 1/2 inch. In one embodiment, the distance between a
compressed suction cup 116 (compressed when the pump assembly 800
is resting on the bottom surface of a reservoir or container within
which water or fluid is to be pumped by the pump assembly 800) and
the full width of the impeller fins 108 (i.e. the distance includes
the full width of the impeller fins 108, thereby ensuring enough
fin surface contact to accelerate the fluid for effective operation
of the pump assembly 800), is approximately 1/2 inch. In one
embodiment, the pump assembly 800 is capable of operating
effectively in water or fluid depth as little as enough to cover
the fins 108 of the impeller assembly 802, when the pump is fully
assembled and sitting with its prefilter assembly 104 (and
pads/suction cups 116 thereon) resting on the bottom surface of the
reservoir or container within which the water or fluid is to be
pumped.
[0036] The terms and expressions which have been employed in the
foregoing specification are used therein as terms of description
and not of limitation, and there is no intention in the use of such
terms and expressions of excluding equivalents of the features
shown and described or portions thereof, it being recognized that
the scope of the invention is defined and limited only by the
claims which follow.
* * * * *