Abstrict A flow meter having a float slideably mounted along a float rod
centrally located within a flow meter body, the float assuming a
height along the flow meter float rod representative of fluid pressure.
The float preferably has a cylindrical-shaped through-bore. The
float rod preferably has a polygonal-shaped perimeter over substantially
its entire length permitting fluid flow between the float rod outer
diameter (OD) and the float inner diameter (ID) to dislodge any
particulate, thereby serving a self-cleaning function. The float
rod is preferably hollow and closed at its upper end and having
flow inlet and flow outlet openings near its lower end communicating
with a flow chamber which conveniently provides the inlet and outlet
flows at the lower end of the flow meter.
Claims What is claimed is:
1. A flow meter, comprising: a flow meter body having a through-bore
for fluid flow therethrough; a float rod positioned within said
through-bore; a float having a through-bore, said float rod extending
through the float through-bore enabling the float to move freely
along said float rod to a position therealong which is determined
by flow rate of a fluid passing therethrough; an interior periphery
of the float and an exterior periphery of the float rod having different
cross-sections so that the cross-sections of the float rod and float
limit surface contact therebetween and further permit fluid flow
through gap regions between points of surface contact to provide
a self-cleaning function; the exterior periphery of the float rod
having a first constant cross-section measured in a longitudinal
direction and the interior periphery of the float having a second
constant cross-second measured in a longitudinal direction to thereby
maintain the self-cleaning function.
2. The apparatus of claim 1 wherein said self-cleaning function
prevents buildup of foreign matter between the inner periphery of
the float and the outer periphery of the float rod due to the fluid
flow through the gap regions.
3. The apparatus of claim 1 wherein said fluid flow through the
gap regions clears foreign matter therefrom, which includes particulate
and oil.
4. The flow meter of claim 1 wherein the inner periphery of the
float is circular and the outer periphery of the float rod is polygonal.
5. The flow meter of claim 1 wherein the inner periphery of the
float is polygonal and the outer periphery of the float rod is circular.
6. The flow meter of claim 4 wherein the polygonal periphery is
a regular polygon having between 4 and 10 equal sides.
7. The flow meter of claim 5 wherein the polygonal periphery is
a regular polygon having between 4 and 10 equal sides.
8. The flow meter of claim 6 wherein the polygonal periphery is
hexagonal.
9. The flow meter of claim 7 wherein the polygonal cross-section
is hexagonal.
10. The flow meter of claim 1 wherein the through-bore of the float
has a circular cross-section and the float rod has an exterior periphery
of alternating undulations and projections.
11. The flow meter of claim 1 wherein the relationship of the through
bore and outer periphery of the float rod is selected to maintain
longitudinal axes of the float rod and float to be substantially
co-axial.
12. A flow meter, comprising: a flow meter body having a through-bore;
a hollow elongated float rod extending through the through-bore
of the flow meter body; a float having a through-bore receiving
said float rod enabling the float to be slideably therealong wherein
the float assumes a position along the float rod which is representative
of a flow rate of a fluid moving through a hollow region between
said float rod and said flow meter body through-bore; an upper end
of the flow meter body having a closure cap which receives and supports
an upper end of the float rod, said closure cap having inlet openings
communicating at an outer radial end with the region between the
flow meter body through-bore and the outer periphery of the float
rod and communicating at an inner radial end with an opening in
an upper end of the hollow float rod; a lower end of the flow meter
body supporting a lower end of the float rod having a first passage
communicating at one end with a fluid flow conduit and communicating
at another end with the region between the flow meter body through-bore
and the outer periphery of the float rod and having a second passage
communicating at one end with an open lower end of the hollow float
rod and communicating at another end with said fluid flow conduit
whereby fluid entering the first passage in the flow meter body
lower end flows upwardly through the flow meter in the region surrounding
the float rod, enters the open upper end of the float rod and ultimately
passes through the open lower end of the float rod to return to
the fluid conduit.
13. The flow meter of claim 12 wherein said flow meter body has
an enlarged outer portion mounted upon said fluid conduit for supporting
the flow meter body on the fluid conduit.
14. The flow meter of claim 12 wherein said closure cap supports
and aligns the upper end of the float rod so that a float rod longitudinal
axis and a longitudinal axis of the flow meter body are substantially
coaxial.
15. The flow-meter of claim 12 wherein said body lower end supports
and aligns the upper end of the float rod so that a float rod longitudinal
axis and a longitudinal axis of said flow meter body are substantially
coaxial.
16. The flow-meter of claim 12 wherein an interior periphery of
the float and an exterior periphery of the float rod having different
cross-sections so that the cross-sections of the float rod and float
limit surface contact therebetween and further permit fluid flow
through regions between points of surface contact to provide a self-cleaning
function.
17. The flow meter of claim 1 an upper end of the flow meter body
having a closure cap which receives and supports an upper end of
the float rod, said closure cap having inlet openings communicating
at an outer radial end with the region between the flow meter body
through-bore and the outer periphery of the float rod and communicating
at an inner radial end with an opening in an upper end of the hollow
float rod.
Description FIELD OF INVENTION
The present invention relates to flow meters. More particularly
the present invention relates to flow meters having a novel self-cleaning
function and further providing a unique passageway arrangement wherein
inlet and outlet openings are conveniently arranged at one end of
the flow meter.
BACKGROUND
Conventional flow meters typically utilize a float member slideable
along a float rod and movable therealong to a position representative
of flow rate.
The fluid passing through the flow meter may, however, carry particulate
which may become lodged between the float and float rod thereby
retarding free movement of the float rod, to yield an incorrect
reading.
It is also desirable to provide a flow meter having a simplified
and desirable flow pattern.
SUMMARY
The present invention provides a flow meter in which the inner
periphery of the float and the outer periphery of the float rod
are designed to provide a self-cleaning flow therebetween as well
as providing a flow pattern utilizing the float rod in which both
incoming and outgoing flows are conveniently arranged at one end
of the flow meter to simplify design.
BRIEF DESCRIPTION OF THE FIGURES
The present invention will be understood from consideration of
figures wherein like elements are designated by like numerals and,
wherein:
FIG. 1 shows a vertical section of a flow meter embodying the principles
of the present invention.
FIG. 2 is a horizontal section of the flow meter of FIG. 1 looking
in the direction of arrows 2--2.
FIGS. 2a and 2b show alternative embodiments of the float rod of
FIG. 2.
FIG. 3 in an enlarged view of a portion of the horizontal section
of FIG. 2.
FIG. 4 is a vertical section of a flow meter designed in accordance
with the principles of the present invention and showing the flow
path therethrough.
FIG. 5 is a horizontal section of the flow meter of FIG. 4 looking
in the direction of arrows 5--5.
DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS
THEREOF
Making reference to FIGS. 1 and 2 the flow meter 10 shown therein
is comprised of a hollow tubular-shaped outer flow meter body 11
which is typically formed of a clear glass or plastic material.
A float rod 12 located along the central longitudinal axis of outer
body 11 slideably receives a float 13 having a hollow through-bore
13a enabling float 13 to be freely slideable along float rod 12.
Float rod 12 may be solid or may have a hollow interior 12a. The
nature of the float rod interior is irrelevant insofar as the effectiveness
of the invention of FIG. 1 is concerned.
In a preferred embodiment, through-bore 13a of float valve 13 has
a substantially circular cross-section whereas the outer perimeter
of float rod 12 in one preferred embodiment, is provided with a
regular polygonal shape such as, for example, a hexagonal or six-sided
regular polygon. As shown in FIGS. 2 and 3 the polygonal shape of
the outer periphery 12a of float rod 12 cooperates with the circular-shaped
through-bore 13a to provide a plurality of clearance regions or
gaps G which permit the flow of fluid therethrough to prevent dirt
and/or oil buildup in the region between the outer periphery 12a
of the float rod 12 and the interior periphery of the float 13.
The through-bore 13a of the float 13 and the outer periphery of
the float rod are designed so that their longitudinal axes are substantially
co-linear. In addition, it should be understood that the polygonal
shape of the float rod outer periphery minimizes the surface contact
between the inner periphery of the float and the outer periphery
of the float rod, thus further minimizing dirt and oil buildup therebetween
and significantly reducing the possibility of foreign matter build-up
at such a small surface contact area.
As an alternative embodiment, the through-bore 13a of float 13
may be provided with a polygonal shape, such as a hexagonal shape
while the outer periphery of the float rod may be provided with
a circular shape which, in addition to providing fluid flow therebetween
likewise minimizes the amount of surface contact therebetween. The
aforementioned shapes further substantially align the longitudinal
axes of the float and float rod along a common axis, i.e., in other
words the axes of the float and float rod are substantially co-linear.
Other shapes may be utilized to accomplish the same result. Note
for example FIGS. 2a and 2b which show alternating projecting portions
and recesses, the curved projecting portions providing limited surface
contact with the interior periphery of the float rod 13 while the
recesses permit fluid flow therethrough to thereby provide the self-cleaning
function.
FIGS. 4 and 5 show another embodiment of the present invention
in which the flow meter 10 is provided with a float rod 12 having
a hollow interior 12b.
A closure cap 15 seals the top end of the flow meter body 11. The
lower end thereof is provided with an opening 15a which receives
the upper end of float rod 12. The closure cap is further provided
with diametrically opposed openings 15b, 15c whose longitudinal
axes are transverse to the longitudinal axis of float rod 12. The
openings 15b and 15c communicate with opening 15a.
The lower end of the flow meter body 11 is closed. The closed lower
end, however, is provided with an inlet opening 11b communicating
with the interior of flow meter body 11 and an outlet opening 11c
communicating with the lower, open end of the hollow float rod 12.
The flow meter body 11 is supported upon housing 16 by enlarged
portion 11d.
The bottom portion of the flow meter body 11 extends into an opening
16a in an upper end of a housing 16 which serves as a support for
the flow meter as well as having hollow interior 16b which serves
as a conduit for fluid flow.
The operation is such that fluid flows in the direction shown by
arrow F1 entering the opening 11b and flowing upwardly through
the hollow region between the inner wall of flow meter body 11 and
the outer wall of float rod 12 as represented by arrows F2. The
fluid flow acts upon float 13 which assumes an equilibrium position
which is a function of flow rate. Gradations (not shown for purposes
of simplicity) are provided along the flow meter body 11 which
is typically transparent, to provide an indication of flow rate.
The upward flow, as shown by arrows F2 is diverted into the openings
15b, 15c as shown by arrows F3 F4 and enter into the top, open
end of float rod 12 and flow downwardly therethrough as shown by
arrows F5. The flow leaves the lower end of float rod 12 entering
passageway 11c and ultimately flowing in the direction shown by
arrow F6.
The arrangement shown in FIGS. 4 and 5 provides a flow meter designed
to have fluid flow enter and exit at the bottom of the flow meter
thereby eliminating the need for an outflow conduit at the upper
end of the flow meter. |