U.S. patent application number 09/761408 was filed with the patent office on 2002-07-18 for flusher having consistent flush-valve-closure pressure.
Invention is credited to Herbert, Kay, Parsons, Natan E..
Application Number | 20020092091 09/761408 |
Document ID | / |
Family ID | 25062086 |
Filed Date | 2002-07-18 |
United States Patent
Application |
20020092091 |
Kind Code |
A1 |
Parsons, Natan E. ; et
al. |
July 18, 2002 |
Flusher having consistent flush-valve-closure pressure
Abstract
A manifold (116) supplies pressurized water through a
pressurizer conduit (30) to a pressure chamber (24) by which the
pressurized water thereby introduced into the pressure chamber (24)
holds a flush valve (12) seated in a flush opening at the base of a
toilet tank (18). The manifold (116) also supplies water through a
fill tube (144) to the interior of the toilet tank (18). A flow
restricter (146) mounted on the valve member (12) fits into the
outlet of the fill tube so as to restrict its flow area when the
flush valve (12) is unseated. This helps maintain the manifold
pressure employed to close the flush valve (12). When that valve
closes, it retracts the flow diverter (146) from the fill tube
(114) to allow the tank to fill rapidly. A flow-rate controller
(148) tends to reduce variations in the pressure applied to the
flush-valve member (12) that would otherwise result from
source-pressure variations. A check valve (154) maintains the
pressure that keeps the flush valve (12) closed, despite loss in
source pressure.
Inventors: |
Parsons, Natan E.;
(Brookline, MA) ; Herbert, Kay; (Winthrop,
MA) |
Correspondence
Address: |
IVAN D. ZITKOVSKY
FRIEZE CRAMER CYGELMAN ROSEN & HUBER LLP
60 WALNUT STREET, 3RD FLOOR
WELLESLEY
MA
02481
US
|
Family ID: |
25062086 |
Appl. No.: |
09/761408 |
Filed: |
January 16, 2001 |
Current U.S.
Class: |
4/378 |
Current CPC
Class: |
E03D 5/024 20130101;
E03D 1/142 20130101 |
Class at
Publication: |
4/378 |
International
Class: |
E03D 001/34 |
Claims
What is claimed is:
1. A flusher comprising: A) a tank forming a flush outlet by which
liquid in the tank may leave the tank for flushing; B) a
flush-valve member operable between an unseated state, in which it
permits flow from the tank through the flush outlet, and a seated
state, in which it prevents flow from the tank therethrough; C) a
valve-operating mechanism including a housing that defines a
control chamber disposed and forms a line-pressure inlet that
admits water line pressure into the control chamber and further
forms a control-chamber pressure-relief outlet, by which pressure
in the control chamber can be relieved, the valve-operating
mechanism operating the flush-valve member to its seated state when
the line pressure prevails in the control chamber and operating the
flush-valve member to its unseated state when the pressure in the
control chamber is relieved D) a pressurizer conduit having an
upstream thereof and a downstream end thereof that so communicates
with the control chamber that pressurized water applied to the
pressurizer conduit at an upstream end thereof can pressurize the
control chamber; and E) a pressure controller interposed in the
pressurizer conduit, the pressurizer conduit imposing a pressure
drop from its upstream to its downstream side that increases and
decreases with upstream pressure.
2. A flusher comprising: A) a tank forming a flush outlet by which
liquid in the tank may leave the tank for flushing; B) a
flush-valve member operable between an unseated state, in which it
permits flow from the tank through the flush outlet, and a seated
state, in which it prevents flow from the tank therethrough; C) a
valve-operating mechanism including a housing that defines a
control chamber disposed and forms a line-pressure inlet that
admits water line pressure into the control chamber and further
forms a control-chamber pressure-relief outlet, by which pressure
in the control chamber can be relieved, the valve-operating
mechanism operating the flush-valve member to its seated state when
the line pressure prevails in the control chamber and operating the
flush-valve member to its unseated state when the pressure in the
control chamber is relieved D) a pressurizer conduit having an
upstream thereof and a downstream end thereof that so communicates
with the control chamber that pressurized water applied to the
pressurizer conduit at an upstream end thereof can pressurize the
control chamber; and E) a check valve interposed in the pressurizer
conduit and oriented to permit flow toward the pressurizer
conduit's upstream end but not toward its up-stream end.
3. A flusher comprising: A) a tank forming a flush outlet by which
liquid in the tank may leave the tank for flushing; B) a
flush-valve member operable between an unseated state, in which it
permits flow from the tank through the flush outlet, and a seated
state, in which it prevents flow from the tank therethrough; C) a
valve-operating mechanism including a housing that defines a
control chamber disposed and forms a line-pressure inlet that
admits water line pressure into the control chamber and further
forms a control-chamber pressure-relief outlet, by which pressure
in the control chamber can be relieved, the valve-operating
mechanism operating the flush-valve member to its seated state when
the line pressure prevails in the control chamber and operating the
flush-valve member to its unseated state when the pressure in the
control chamber is relieved D) a manifold having an inlet and
pressurizer and fill outlets; E) a pressurizer conduit having an
upstream thereof in fluid communication with the pressurizer outlet
and a downstream end thereof that so communicates with the control
chamber that pressurized water applied to the pressurizer conduit
at an upstream end thereof can pressurize the control chamber; F) a
fill conduit having an upstream thereof in fluid communication with
the fill outlet and a downstream end thereof from which the tank
can be filled; and G) a flow diverter so mounted on the flush-valve
member as to extend into the downstream end of the pressurizer
conduit as to restrict the flow area therethrough when the flush
valve is in its unseated state but leave a greater flow area when
the flush valve is in its seated state.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is directed to toilet flushing. It
finds particular application in tank-type flushers.
[0003] 2. Background Information
[0004] The art of toilet flushers is an old and mature one. (We use
the term toilet here in its broad sense, encompassing what are
variously referred to as toilets, water closets, urinals, etc.)
While many innovations and refinements in this art have resulted in
a broad range of approaches, flush systems can still be divided
into two general types. The first is the gravity type, which is
used in most American domestic applications. The gravity type uses
the pressure resulting from water stored in a tank to flush the
bowl and provide the siphoning action by which the bowl's contents
are drawn from it. The second type is the pressurized flusher,
which uses line pressure more or less directly to perform
flushing.
[0005] Some pressure-type flushers are of the tank type. Such
flushers employ pressure tanks to which the main water-inlet
conduit communicates. Water from the main inlet conduit fills the
pressure tank to the point at which air in the tank reaches the
main-conduit static pressure. When the system flushes, the water is
driven from the tank at a pressure that is initially equal to that
static pressure, without reduction by the main conduit's flow
resistance. Other pressure-type flushers use no pressure tank, and
the main conduit's flow resistance therefore reduces the initial
flush pressure.
[0006] While flush-mechanism triggering has historically been
performed manually, there is also a long history of interest in
automatic operation. Particularly in the last couple of decades,
moreover, this interest has resulted in many practical
installations that have obtained the cleanliness and other benefits
that automatic operation affords. As a consequence, a considerable
effort has been expended in providing flush mechanisms that are
well adapted to automatic operation. Automatic operation is well
known in pressure-type flushers of the non-tank variety, but
gravity-type flushers and pressurized flushers of the tank-variety
have also been adapted to automatic operation.
[0007] European patent publication EPO 0 828 103 A1 illustrates a
typical gravity arrangement. The flush-valve member is biased to a
closed position, in which it prevents water in the tank from
flowing to the bowl. A piston in the valve member's shaft is
disposed in a cylinder. A pilot valve controls communication
between the main (pressurized) water source and the cylinder. When
the toilet is to be flushed, only the small amount of energy
required for pilot-valve operation is expended. The resultant
opening of the pilot valve admits line pressure into the cylinder.
That pressure exerts a relatively large force against the piston
and thereby opens the valve against bias-spring force. Pilot valves
have similarly been employed to adapt pressure-type flushers to
automatic operation.
[0008] Commonly assigned copending U.S. application Ser. No.
09/544,800, which was filed on Apr. 7, 2000, by Parsons et al. for
an Automatic Tank-Type Flusher and is hereby incorporated by
reference, describes an arrangement in which the flush valve is
biased to its unseated state, in which it permits flow from the
tank to the bowl, and it uses line pressure to hold the flush valve
shut rather than to open it. That approach tends to make it
relatively simple to have a repeatable valve-opening profile. Also,
high line pressure actually aids in preventing leakage through the
flush valve; unlike some other arrangements, such pressure does not
tend to reduce the flush-valve seal's effectiveness. Since the
toilet's suction generation is principally dependent on the
valve-opening profile, and since this approach makes the bias
mechanism essentially the sole determinant of that profile, that
approach makes the valve-opening aspect of flush operation largely
independent of line pressure.
[0009] As is indicated in commonly assigned U.S. patent application
Ser. No. 09/716,870, filed on Nov. 20, 2000, by Parsons et al. for
a Timed Fluid-Linked Flush Control and hereby incorporated by
reference, moreover, that approach has applicability not only to
automatic flushers but also to flushers that are manually
operated.
SUMMARY OF THE INVENTION
[0010] We have recognized that this approach to flush control can
be further improved so that this approach results not only in
more-effective valve opening but also in more-effective valve
closing. According to one aspect of the invention, a flow diverter
operated by the flush valve impedes or prevents tank filling while
the flush valve is in its open state. This limits line-pressure
reduction that the filling operation might otherwise cause, so the
line pressure available to close the flush valve tends to be better
preserved.
[0011] In accordance with another aspect of the invention, a flow
controller is interposed in the path by which the line pressure is
applied to the flush valve to close it. The flow controller can be
of any of the many types that tend to reduce pressure variation. By
so including such a flow controller in that pressurizing path, a
system employing that feature exhibits relatively consistent
flush-valve-closing performance despite variations in line
pressure.
[0012] In accordance with yet another aspect of the invention, a
check valve is included in the path by which fluid to apply closing
pressure to the flush valve is delivered to it. By employing this
feature, the flush system can maintain flush-valve-sealing pressure
despite a temporary loss in line pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention description below refers to the accompanying
drawings, of which:
[0014] FIG. 1 is a sectional view of the toilet tank illustrating
its float and gravity-type flush valves;
[0015] FIG. 2 is a more-detailed cross section of the flush-valve
mechanism;
[0016] FIG. 3 is a cross-sectional view of a remote actuator valve
and push button;
[0017] FIG. 4 is a top isometric view of one of the push-button
members in the push-button assembly of FIG. 3;
[0018] FIG. 5 is an isometric view of the button frame in FIG. 3's
push-button assembly;
[0019] FIG. 6 is an isometric view of another button member from
the push-button assembly of FIG. 3;
[0020] FIG. 7 is a more-detailed cross-sectional view of FIG. 1's
float-valve assembly; and
[0021] FIG. 8 is a cross-sectional view of the flush-valve assembly
showing a fill tube and flow diverter.
DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT
[0022] In the state that FIG. 1 depicts, a bias spring 10 keeps a
gravity-type flush mechanism's flush-valve member 12 separated from
a flush-valve seat 14 formed on the inlet of a flush conduit 16
disposed in the bottom of a toilet tank 18. As FIG. 2 shows in more
detail, a lower main housing half 20 mounted by struts 22 on the
flush conduit 16 forms a pressure chamber 24 above the valve member
12. The pressure chamber, which is partially defined by a cylinder
26 within which a piston portion 28 of the valve member 12 is
slideable, is ordinarily under pressure because of fluid
communication that a pressure line 30 provides between it and a
pressurized-water supply. When that pressure prevails, it holds the
valve member 12 in a seated position rather than the illustrated,
unseated position.
[0023] Pressure chamber 24's pressure ordinarily prevails because a
pilot-valve diaphragm 32 secured in housing half 20 by a
pilot-valve cap 33 ordinarily cooperates with the valve member's
seal ring 34 to prevent escape of pressurized water from the
chamber. The pilot-valve diaphragm 32 is resiliently deformable, so
the pressure that prevails within chamber 24 would tend to lift it
from engagement with a pilot-valve seat 36 and thus allow pressure
relief if a similar pressure did not prevail within a pilot chamber
38 and act on the diaphragm 32 over a greater area. The reason why
this pressure prevails within the pilot chamber 38 is that a small
orifice 40 through which a pilot-valve pin 42 formed by cap 33
extends permits water to bleed (through a relatively high flow
resistance) into the pilot chamber. So the valve member 12 remains
in the seated position (not shown) between flushes.
[0024] To cause the system to flush, the user depresses a push
button 44 (FIG. 1). As will be explained in more detail below, this
causes a remote pressure-relief valve 46 to permit flow to its
outlet 48 from a pressure-relief tube 50 secured at its other end
by a fitting 52 to a plug member 54 mounted on cap 33. This places
the remote valve 46's outlet 48 in communication with a plug member
54's interior passage 56 (FIG. 2) and thereby with the pilot
chamber 38 through passage 58. This relieves pressure in that
chamber. The flow resistance of the path is much lower than that of
the bleed orifice 40, by which the pilot valve's pressure is
replenished, so the pressure within chamber 38 drops and permits
pressure chamber 24's pressure to raise diaphragm 32 off its seat.
The diaphragm thus serves as a pressure-relief valve. Specifically,
it permits the pressure within the pressure chamber 24 to be
relieved through a plurality of openings such as opening 60. As a
consequence, the bias spring 10 can overcome the force exerted by
the now-reduced pressure within chamber 24. The flush-valve member
12 therefore rises to its FIG. 1 position, lifting its O-ring seal
62 off the main valve seat 14 and thereby allowing water from the
tank to flow out through the flush conduit 16.
[0025] Now, the user typically will may not keep the push button 44
depressed long enough for the required flush volume to flow. But
the remote valve 46 nonetheless remains open long enough, as will
now be explained by reference to FIG. 3. As that drawing shows, the
push button 44 actually is a compound button consisting of outer
and inner button members 64 and 66 held in a button frame 68 by a
button cap 70. A flexible diaphragm 72 secured to the frame 68 by
an actuator-chamber housing 74 biases the inner button 66 to the
illustrated rest position, in which it additionally holds the outer
button member 64 in its rest position.
[0026] FIG. 4 is a top isometric view of the inner button member
66. That drawing shows that button member 66 includes a central
land 76 extending from a generally disk-shaped layer 78 from which
four keys 80 extend radially. As FIG. 5 shows, the button frame
forms a set of sixteen partitions 82 extending radially inward.
Those partitions 82 cooperate to define sixteen key guides, within
any four of which FIG. 4's keys 80 can slide. The button frame 68
also forms stop surfaces 84 at the bases of the key guides thus
formed. The stop surfaces 84 in the key guides occupied by the four
keys at any one time are all arranged at the same level so that
they stop all four keys simultaneously. But different sets of four
stops are disposed at different levels so that placing the keys in
different sets of the key guides results in different amounts of
permitted button travel, for reasons that will be explained in due
course.
[0027] As FIG. 4 shows, each of the four keys 80 forms a passage 86
therethrough. FIG. 6, which is an isometric view of the outer
button member 64, shows that the outer button member is generally
annular but forms four radially extending tabs 88 from which
respective legs 90 extend. Those legs register with FIG. 4's
passages 84 and, as FIG. 3 shows, extend through them.
[0028] When the user operates the push button 44, he most often
presses against the outer button member 64 and thereby depressed
that member until its legs 90 reach the respective key guides' stop
surfaces. The outer button member 64 bears against the inner button
member 66, moving it to the right in FIG. 3 and causing it to
deform the flexible diaphragm 72 from its illustrated position, to
which it is biased. A valve housing 92 secured to the
actuator-chamber housing 74 holds in place a second flexible
diaphragm 94, which cooperates with diaphragm 72 and the
actuator-chamber housing 74 to form an actuator 20 chamber. The
actuator chamber is filled with an incompressible fluid, and button
member 66's deformation of diaphragm 72 forces the fluid through
four angularly spaced openings 96 in a divider wall 98 that the
actuator-chamber housing 74 forms. In flowing through openings 96,
the fluid lifts the lip of an umbrella-type check-valve member 100
snap fit in a central divider-wall opening.
[0029] The fluid's motion urges diaphragm 94 rightward in FIG. 3
against the force of a bias spring 101 and thereby pushes to the
right a valve member 102 slidably disposed in a valve channel 104
formed by the valve housing 92. Valve member 102 forms two annular
recesses in which respective O-ring seals 106 and 108 are disposed,
and the rightward motion causes O-ring 108 to extend into a widened
portion 110 of channel 104 and thereby break the seal that it had
theretofore maintained with the channel wall. Pressure theretofore
prevailing in tube 50 is thereby relieved through channel 104 and
outlet passage 48. When the user depresses only the outer button
member 64, the point at which that members' legs 90 encounter their
respective lands 84 determines how far into the widened channel
portion 110 valve member 102 extends.
[0030] When the user releases the button, flexible diaphragms 72
and 94 tend to resume the rest positions to which spring 101 biases
them, so they act to return the valve 46 to its closed state. To
resume the rest positions, they must move the actuator chamber's
fluid back through the dividing wall 98. But check valve 100
prevents fluid from flowing through openings 96, and the only route
through the wall that remains is therefore a bleed orifice 112,
which imposes significant flow resistance and therefore a delay
between the user's releases of the button and valve 46's
closure.
[0031] The duration of the delay depends on the amount of diaphragm
deformation that occurred, and this in turn depends on how far
button member 64 traveled. The amount of that travel is determined
by the selection of the key guides into which that button member's
keys 80 were placed; different-level stop surfaces 84 result in
different amounts of travel of legs 90 before they encounter those
stop surfaces, but the resultant delay is usually at least two
seconds.
[0032] The delay imposed as a result of the user's depressing only
the outer button member 66 is usually so selected as not to permit
the tank to empty completely but still to permit enough flushing
flow for most purposes. If the user desires a fuller flush, he
instead depresses the inner button member 66's land 76 (FIG. 4).
Button member 66 can travel farther than member 64; it can travel
until its keys 80 reach respective stop surfaces 84. As a
consequence, its operation causes more of the incompressible fluid
to flow through the divider wall 98, and it thus requires more of
the fluid to return upon the button's release before the valve 46
returns to its closed position. More of the tank's contents
therefore flow into the toilet bowl to flush it.
[0033] When the water level in the tank has fallen significantly
below a full-tank level, a float 110 shown in FIG. 7 permits the
float valve 112 to open. That valve is mounted in an upper
main-housing half 114 supported on the lower main-housing half. The
main housing is provided in two halves so that the float-valve
assembly 112's height, and thus the level to which the tank is
allowed to fill, can be adjusted by means not shown.
[0034] A main pressure-inlet manifold 116, which feeds the conduit
30 by which pressure chamber 24 is pressurized, forms a further
outlet 118. Through this outlet it feeds a conduit 120 mounted on
the upper main-housing half 114 and forming at its lower edge a
float-valve seat 122. Formed integrally with the conduit 120 is a
generally annular mouth portion 124 in which a pilot-chamber base
126 is threadedly secured. That base cooperates with the conduit
120's mouth portion 124 to form a float-valve pilot chamber 128 and
secure within it a resiliently deformable float-valve diaphragm 130
that tends to seal against the float-valve seat 122. However, a
bleed orifice in which is disposed a positioning pin 134 formed by
the pilot-chamber base 126 permits fluid from the conduit 120 to
enter the pilot-valve chamber 128. When a pilot-valve member 136 is
held by the float 110 against the outlet of a pressure-relief
passage 138, the pressure in the pilot-valve chamber 128 can build
up to equal the pressure in the conduit 120 and, prevailing over a
larger area than the pressure from the conduit 120, hold the
float-valve diaphragm 130 seated so that it prevents the liquid in
conduit 120 from flowing around the float-valve seat 122 through
mouth-portion openings 140 and a port 142 to a tank-fill tube
144.
[0035] When the tank level is low, though, the float 110 does not
stop pressure-relief passage 138, so pressure in the pilot-valve
chamber 128 is relieved faster than it can be restored through the
bleed orifice 132. The pressure in conduit 120 therefore unseats
the float-valve diaphragm 130, so water from conduit 120 can flow
into the fill tube 144.
[0036] The fill tube's purpose is to fill the tank, and the
tank-filling flow tends to reduce the manifold pressure. Since that
pressure is what closes the flush valve, significant tank-filling
flow might impair that valve's closing performance. So long as the
flush-valve member 12 is in its fully unseated position, though,
water cannot flow at any significant rate from the fill tube 144
into the tank. This is because, as FIG. 8 shows, a flow restricter
146 mounted on the flush-valve member so protrudes into the fill
tube's outlet as to restrict the tube's flow area greatly. This has
the beneficial effect of maintaining high pressure in the manifold
116 and thus the pressure line 130 by which, through bleed orifice
140, the manifold pressure closes the pilot valve and thus imposes
on the flush valve the pressure that closes it. In other words, the
flow restricter ensures that there is enough pressure to close the
flush valve with significant speed.
[0037] When the flush valve does close, it retracts the flow
restricter 140 from the fill tube 144 and thereby allows the tank
to fill rapidly.
[0038] The flow-restricter operation just described tends to make
the flush valve's operation more predictable in duration than it
would otherwise be; tank filling does not adversely affect the
pressure that operates to close the flush valve. However, the
pressure from the water source can vary, and this, too, could
result in undesired variations in the delay between the remote
valve's closing and that of the flush valve. A flow-rate controller
148 (FIG. 1) interposed in the flow path by which the
flush-valve-closing pressure is supplied reduces this effect. The
particular type of flow controller is not critical, but FIG. 8
depicts one of the deformable-ring variety. A flow restricter 150
disposed in the conduit cooperates with a resiliently deformable
ring 152 to restrict the flow area through which pressurized water
must flow to enter the pressure chamber that applies the closing
force to the flush valve. If the supply pressure is relatively low,
it does not greatly deform the ring, and the resultant flow area is
relatively great: the already-low pressure is not reduced much in
flowing through the restricter. If the supply pressure is high, on
the other hand, it deforms the ring by a greater amount and thereby
restricts the flow area more significantly. So a greater pressure
drop from the originally high pressure occurs. The flow-rate
controller therefore reduces the pressure variation that the flush
valve would otherwise experience. This reduces variation in the
speed at which the flush valve closes.
[0039] Plumbing installations can experience not only pressure
variation but also total pressure loss. In the absence of the
present invention, such a pressure loss would permit the flush
valve to open, causing an unintended flush. But a check valve 154
is provided in the pressurizer conduit 30 so that the pressure
holding the flush valve closed is not lost when the line pressure
is.
* * * * *