U.S. patent application number 10/875363 was filed with the patent office on 2005-12-29 for flush valve.
Invention is credited to Barham, Mitchell C., Knight, David P., Tilson, Alexander Q..
Application Number | 20050283895 10/875363 |
Document ID | / |
Family ID | 35503877 |
Filed Date | 2005-12-29 |
United States Patent
Application |
20050283895 |
Kind Code |
A1 |
Tilson, Alexander Q. ; et
al. |
December 29, 2005 |
Flush valve
Abstract
Described here are flush valves for delivering a selected amount
of water from a toilet tank into a toilet bowl, particularly
collapsible flush valves having substantial durability and
resistance to wear and deleterious chemicals. These flush valves
have a collapsible member extending from above the surface of the
water in the toilet tank to the tank outlet in the normal (closed
flush valve) state. Collapsing the flush valve allows water to flow
into the toilet bowl through the flush valve until the toilet tank
is drained to the level of the collapsed flush valve and buoyancy
is restored. Flush valves may be made of a material that does not
substantially deteriorate in the presence of halogen-containing
toilet disinfectants, and the outer surface (the water contacting
surface) of the flush valves may be a single continuous piece.
Inventors: |
Tilson, Alexander Q.;
(Burlingame, CA) ; Knight, David P.; (Mountain
View, CA) ; Barham, Mitchell C.; (San Mateo,
CA) |
Correspondence
Address: |
MORRISON & FOERSTER LLP
755 PAGE MILL RD
PALO ALTO
CA
94304-1018
US
|
Family ID: |
35503877 |
Appl. No.: |
10/875363 |
Filed: |
June 23, 2004 |
Current U.S.
Class: |
4/378 |
Current CPC
Class: |
E03D 1/34 20130101; E03D
1/304 20130101; E03D 1/142 20130101 |
Class at
Publication: |
004/378 |
International
Class: |
E03D 001/34 |
Claims
What we claim is:
1. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further to release water from the toilet tank through the
tank outlet in a second longitudinally collapsed position, wherein
the collapsible member comprises one or more materials that do not
substantially deteriorate in the presence of halogen-containing
toilet disinfectant solutions; and wherein the flush valve has no
valve seat.
2. The flush valve of claim 1, wherein the flush valve further
comprises at least one ballast weight.
3. The flush valve of claim 1, wherein the collapsible member is
fabricated as a single piece by molding.
4. The flush valve of claim 3, wherein the collapsible member is
fabricated as a single piece by injection molding.
5. The flush valve of claim 1, wherein the collapsible member is
further configured to be relaxed in the extended position.
6. The flush valve of claim 1, further comprising a tipping
actuator for collapsing the collapsible member of the flush
valve.
7. The flush valve of claim 1 further comprising a base region and
a float region that are fabricated with the collapsible member as a
continuous single piece; and further wherein sinking the float
region allows the collapsible member to collapse and allows water
to flow through the collapsible member and out of the tank
outlet.
8. The flush valve of claim 7, wherein the base region, float
region, and collapsible member are fabricated as a single piece by
molding.
9. The flush valve of claim 1, wherein the collapsible member is
configured as a collapsible bellows.
10. The flush valve of claim 9, wherein the collapsible bellows has
a continuous spiral thread.
11. The flush valve of claim 9, wherein the collapsible bellows is
tapered.
12. The flush valve of claim 1, wherein the flush valve is
fabricated from a polyolefin.
13. The flush valve of claim 12, wherein the flush valve is
fabricated from a Very Low Density Polyethylene.
14. The flush valve of claim 12, wherein the flush valve is
fabricated from an Ultra Low Density Polyethylene.
15. The flush valve of claim 1, wherein the flush valve is
fabricated from soft vinyl.
16. The flush valve of claim 1, further comprising a longitudinal
shaft coupled to the collapsible member wherein the shaft is
configured to substantially guide the flush valve when the
collapsible member collapses.
17. A method of using a flush valve in a toilet tank containing
water comprising: at least partially sinking a flush valve
comprising: a collapsible member configured to extend from the
water surface to the tank outlet in a first extended position and
to maintain the water in the toilet tank, and further to release
water from the toilet tank through the tank outlet in a second
longitudinally collapsed position, wherein the collapsible member
comprises one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions.
18. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further to release water from the toilet tank through the
tank outlet in a second longitudinally collapsed position, and
further configured to be relaxed in the extended position; and
wherein the flush valve has no valve seat.
19. The flush valve of claim 18 wherein the flush valve further
comprises at least one ballast weight.
20. The flush valve of claim 18 wherein the collapsible member is
fabricated as a single piece by molding.
21. The flush valve of claim 20, wherein the collapsible member is
fabricated as a single piece by injection molding.
22. The flush valve of claim 18, further comprising a tipping
actuator for collapsing the collapsible member of the flush
valve.
23. The flush valve of claim 18 further comprising a base region
and a float region that are fabricated with the collapsible member
as a continuous single piece; and further wherein sinking the float
region allows the collapsible member to collapse and allows water
to flow through the collapsible member and out of the tank
outlet.
24. The flush valve of claim 23, wherein the base region, float
region, and collapsible member are fabricated as a single piece by
molding.
25. The flush valve of claim 18, wherein the collapsible member is
configured as a collapsible bellows.
26. The flush valve of claim 25, wherein the collapsible bellows
has a continuous spiral thread.
27. The flush valve of claim 25, wherein the collapsible bellows is
tapered.
28. The flush valve of claim 18, further comprising a longitudinal
shaft coupled to the collapsible member wherein the shaft is
configured to substantially guide the flush valve when the
collapsible member collapses.
29. A method of using a flush valve in a toilet tank containing
water comprising: at least partially sinking a flush valve
comprising: a collapsible member configured to extend from the
water surface to the tank outlet in a first extended position and
to maintain the water in the toilet tank, and further to release
water from the toilet tank through the tank outlet in a second
longitudinally collapsed position, and further configured to be
relaxed in the extended position.
30. A flush valve for delivering water to a toilet bowl from a
toilet tank comprising: a base region configured to connect to the
outlet port of a toilet tank; a floatable and sinkable float region
having an opening that is held above the surface of the water when
the float region is floating, and wherein the float region is
linked to the base region through a collapsible member extending
from the base region to the float region; wherein the base region,
float region and collapsible member are fabricated as a single
piece, and further wherein sinking the float region allows water to
flow through the opening of the float region and out of the outlet
port of the toilet tank.
31. The flush valve of claim 30 further comprising at least one
ballast weight.
32. The flush valve of claim 30, wherein the base region, float
region and collapsible member are fabricated as a single piece by
molding.
33. The flush valve of claim 32, wherein the base region, float
region and collapsible member are fabricated as a single piece by
injection molding.
34. The flush valve of claim 30, further comprising a tipping
actuator for collapsing the collapsible member of the flush
valve.
35. The flush valve of claim 30, wherein the collapsible member is
configured as a collapsible bellows.
36. The flush valve of claim 35, wherein the collapsible bellows
has a continuous spiral thread.
37. The flush valve of claim 35, wherein the collapsible bellows is
tapered.
38. The flush valve of claim 30, further comprising a longitudinal
shaft coupled to the collapsible member wherein the shaft is
configured to substantially guide the flush valve when the
collapsible member collapses.
39. A method of using a flush valve comprising: at least partially
sinking a float region of a flush valve in a toilet tank having an
outlet port in fluid connection with a toilet bowl, the flush valve
comprising: a base region configured to connect to an outlet port
of the toilet tank; a variably buoyant float region configured to
switch between a high buoyant state and a low buoyant state, and
having an opening that is held above the surface of the water when
the float region is highly buoyant, and further wherein the float
region is linked to the base region through a collapsible member
extending from the base region to the float region; wherein the
float region and the collapsible member are fabricated as a single
piece from one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions.
40. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further to release water from the toilet tank through the
tank outlet in a second longitudinally collapsed position; and a
ballast weight sufficient to collapse the collapsible member,
wherein the flush valve has no valve seat.
41. The flush valve of claim 40 wherein the collapsible member is
fabricated as a single piece by molding.
42. The flush valve of claim 41, wherein the collapsible member is
fabricated as a single piece by injection molding.
43. The flush valve of claim 40, further comprising a tipping
actuator for collapsing the collapsible member of the flush
valve.
44. The flush valve of claim 40, wherein the collapsible member is
configured as a collapsible bellows.
45. The flush valve of claim 44, wherein the collapsible bellows
has a continuous spiral thread.
46. The flush valve of claim 44, wherein the collapsible bellows is
tapered.
47. The flush valve of claim 40, further comprising a longitudinal
shaft coupled to the collapsible member wherein the shaft is
configured to substantially guide the flush valve when the
collapsible member collapses.
48. A method of using a flush valve in a toilet tank containing
water comprising: at least partially sinking a flush valve
comprising: a collapsible member configured to extend from the
water surface to the tank outlet in a first extended position and
to maintain the water in the toilet tank, and further to release
water from the toilet tank through the tank outlet in a second
longitudinally collapsed position; and a ballast weight sufficient
to collapse the collapsible member.
49. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a molding-formed
collapsible member configured to extend from the water surface to
the tank outlet in a first extended position and to maintain the
water in the toilet tank, and further to release water from the
toilet tank through the tank outlet in a second longitudinally
collapsed position, and further configured to be spirally threaded,
wherein the flush valve has no valve seat.
50. The flush valve of claim 49 wherein the collapsible member is
fabricated as a single piece by molding.
51. The flush valve of claim 50, wherein the collapsible member is
fabricated as a single piece by injection molding.
52. The flush valve of claim 49, further comprising a tipping
actuator for collapsing the collapsible member of the flush
valve.
53. The flush valve of claim 49, wherein the collapsible member is
tapered.
54. The flush valve of claim 49, further comprising a longitudinal
shaft coupled to the collapsible member wherein the shaft is
configured to substantially guide the flush valve when the
collapsible member collapses.
55. A method of using a flush valve in a toilet tank containing
water comprising: at least partially sinking a flush valve
comprising: a molding-formed collapsible member configured to
extend from the water surface to the tank outlet in a first
extended position and to maintain the water in the toilet tank, and
further to release water from the toilet tank through the tank
outlet in a second longitudinally collapsed position, and further
configured to be spirally threaded.
56. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further to release water from the toilet tank through the
tank outlet in a second longitudinally collapsed position, and
further configured to be relaxed in the extended position, wherein
the collapsible member comprises one or more materials that do not
substantially deteriorate in the presence of halogen-containing
toilet disinfectant solutions; and wherein the flush valve has no
valve seat.
57. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further configured to release water from the toilet tank
through the tank outlet in a second longitudinally collapsed
position, wherein the collapsible member comprises one or more
materials that do not substantially deteriorate in the presence of
halogen-containing toilet disinfectant solutions, and wherein the
collapsible member is fabricated as a single continuous piece; and
wherein the flexible valve has no valve seat.
58. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, and further configured to release water from the toilet tank
through the tank outlet in a second longitudinally collapsed
position, wherein the collapsible member comprises one or more
materials that do not substantially deteriorate in the presence of
halogen-containing toilet disinfectant solutions, and wherein the
collapsible member is fabricated as a single continuous piece, and
further wherein the collapsible member is configured to be
substantially relaxed in the extended position.
59. A flush valve for delivering water to a toilet bowl from a
toilet tank comprising: a base region configured to connect to the
outlet port of a toilet tank; a floatable and sinkable float region
having an opening that is held above the surface of the water when
the float region is floating, and wherein the float region is
linked to the base region through a collapsible member extending
from the base region to the float region; at least one ballast
weight; wherein the collapsible member is relaxed in the extended
position, and further wherein the base region, float region and
collapsible member are fabricated as a single piece, and further
wherein sinking the float region allows water to flow through the
opening of the float region and out of the outlet port of the
toilet tank.
60. A flush valve for controllably delivering a selected amount of
water to a toilet bowl from a toilet tank, the toilet tank having a
water surface and a tank outlet, comprising: a collapsible member
configured to extend from the water surface to the tank outlet in a
first extended position and to maintain the water in the toilet
tank, further configured to release water from the toilet tank
through the tank outlet in a second longitudinally collapsed
position, and further configured to be relaxed in the extended
position, and at least one ballast weight sufficient to collapse
the collapsible member; wherein the collapsible member comprises
one or more materials that do not substantially deteriorate in the
presence of halogen-containing toilet disinfectant solutions, and
wherein a region of the collapsible member is configured as a
collapsible bellows having at least one continuous thread, and
wherein the collapsible member is fabricated as a single continuous
piece by injection molding.
61. A method of using a flush valve in a toilet tank containing
water comprising: at least partially sinking a flush valve
comprising: a collapsible member configured to extend from the
water surface to the tank outlet in a first extended position and
to maintain the water in the toilet tank, and further configured to
release water from the toilet tank through the tank outlet in a
second longitudinally collapsed position, wherein the collapsible
member comprises one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions, and wherein the collapsible member is
fabricated as a single continuous piece, and further wherein the
collapsible member is further configured to be substantially
relaxed in the extended position.
62. A method of installing a flush valve in a toilet tank having an
outlet port in fluid connection with a toilet bowl comprising:
providing a flush valve comprising: a base region configured to
connect to the outlet port of a toilet tank; a variably buoyant
float region configured to switch between a high buoyant state and
a low buoyant state, and having an opening that is held above the
surface of the water when the float region is highly buoyant, and
further wherein the float region is linked to the base region
through a collapsible member extending from the base region to the
float region; wherein the float region and the collapsible member
are fabricated as a single piece; installing the flush valve on the
outlet port of a toilet tank.
63. The method of claim 62 wherein the flush vale is installed by
tightening a nut.
64. A method of fabricating a flush valve comprising: injection
molding a flush valve comprising: a base region configured to
connect to the outlet port of a toilet tank; a variably buoyant
float region configured to switch between a high buoyant state and
a low buoyant state, and having an opening that is held above the
surface of the water when the float region is highly buoyant, and
further wherein the float region is linked to the base region
through a collapsible member extending from the base region to the
float region; wherein the float region, base region and the
collapsible member are injection molded as a single piece.
65. The method of claim 64 wherein the flush valve is injection
molded from one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions.
66. The method of claim 64 wherein the flush valve is tapered.
67. A method of fabricating a flush valve comprising: injection
molding a collapsible member configured to extend from the upper
water surface of a substantially filled toilet tank to the tank
outlet in a first extended position and to maintain the water in
the toilet tank, and further configured to release water from the
toilet tank through the tank outlet in a second longitudinally
collapsed position, wherein the collapsible member is further
configured to be substantially relaxed in the extended
position.
68. The method of claim 66 wherein the collapsible member is
injection molded from one or more materials that do not
substantially deteriorate in the presence of halogen-containing
toilet disinfectant solutions.
69. A method of fabricating a flush valve comprising: injection
molding a collapsible member configured to extend from the upper
water surface of a substantially filled toilet tank to the tank
outlet in a first extended position and to maintain the water in
the toilet tank, and further configured to release water from the
toilet tank through the tank outlet in a second longitudinally
collapsed position, wherein the collapsible member is injection
molded from one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions.
Description
FIELD
[0001] Described here are flush valves for delivering a selected
amount of water from a toilet tank into a toilet bowl, particularly
collapsible flush valves having substantial durability and
resistance to wear and deleterious chemicals. Also described are
methods of making and using the described valves. These flush
valves typically include a collapsible member extending from above
the surface of the water in the toilet tank to the tank outlet in
the normal (closed flush valve) state. The flush valve is relaxed
in the extended (closed) position. Collapsing the flush valve
allows water to flow into the toilet bowl through the flush valve
until the toilet tank is drained to the level of the collapsed
flush valve and buoyancy is restored. The valves may be made of a
material that does not substantially deteriorate in the presence of
halogen-containing toilet disinfectants. At least the outer surface
(the water contacting surface) of the flush valves may be a single
continuous piece.
BACKGROUND
[0002] Most residential toilets use a flapper valve to regulate the
passage of water from the toilet tank to the toilet bowl. A toilet
is typically flushed by depressing the flush handle to lift the
flapper valve, thereby allowing water in the toilet tank to exit
into the bowl. Water continues to flow from the toilet tank into
the bowl until the flapper valve pivots back down to once more seal
the tank, allowing the toilet tank to refill.
[0003] Water conservation is increasingly important to water
districts and to individuals faced with finite (or often dwindling)
supplies, greater costs, and often growing demand for water
resources. Toilets are the largest single water user in most homes,
and flapper valves are the number one source of household water
leakage. The flapper valve is prone to leakage because it is a
moving seal that must be unsealed and resealed with every flush.
According to a study conducted by the US Department of Housing and
Urban development, 20% of household toilets leak, including 12% of
low-flush toilets, primarily due to failure of the flapper
valve.
[0004] A number of factors can contribute to leakage or failure of
flapper valves. For example, debris can become lodged between the
flapper and its seating seal (valve seat). Moreover, the flapper
valve is ordinarily submerged in the toilet tank, and water and/or
toilet bowl cleansers may corrode, rot or swell the flapper valve.
Halogenated toilet bowl cleaners are particularly destructive to
flapper valves. Further, flappers can warp or deform due to
swelling or age. Algae can also grow on the flapper valve parts,
adversely affecting performance. Finally, flapper valves may become
misaligned with continuous use. Ironically, flapper valve leakage
often increases after replacement of an existing flapper valve,
perhaps because the new flapper valve is mismatched to the existing
valve seat. There are currently no "standard" flapper valve
geometries and it is difficult to know which valves to use to
replace existing valves.
[0005] It is desirable to provide a flush valve which is less
likely to leak, and which may be readily adapted to existing toilet
tank designs. Currently, there are no commercially available flush
valves that significantly resist leaking and are resistant to
corrosion by the strongest available toilet bowl cleansers.
[0006] Two similar types of flush valves have been suggested to
replace flapper valves: collapsible tubes, and siphon-type flush
valves.
[0007] U.S. Pat. Nos. 6,381,764 and 6,199,221 to Stalhut show a
toilet tank flush valve with a collapsible tube attached by O-rings
to the tank outlet and also to a float which is capable of
switching between high and low buoyancy. The valve is operated by
depressing an actuating rod held in the middle of the collapsible
tube. Similar collapsible tube valves are shown in U.S. Pat. No.
6,397,404 to Ferreyra et al., U.S. patent application No.
2003/0233703 to Parker, U.S. Pat. Nos. 3,183,526 and 3,280,407 to
Aaron, U.S. Pat. No. 815,661 to Vissing, and U.S. Pat. No. 692,611
to Burgum.
[0008] U.S. Pat. No. 6,473,912 to Preciado-Villanueva shows a
siphon flush valve in which a sliding conduit is attached (by a
fixing means such as adhesives or mechanical means, column 3, line
65) to a fixed conduit and attached to a flow-directing element.
The valve is operated by pushing down on the flow-directing element
so that water begins to siphon into the sliding conduit. Similar
collapsible tube valves are shown in U.S. Pat. No. 386,918 to
Demarest.
[0009] None of the cited prior art suggests the device and methods
described and claimed below.
SUMMARY
[0010] Described here are flush valves and methods for installing,
using and making them. In particular, this application describes
collapsible flush valves having substantial durability and
resistance to wear and deleterious chemicals. The flush valves
described herein may be used to controllably deliver a selected
amount of water from a toilet tank into a toilet bowl without using
a valve seat, because the flush valve operates by buoyantly holding
the opening into the tank outlet port above the surface of the
water in the toilet tank until the toilet is flushed.
[0011] In one version a flush valve for controllably delivering a
selected amount of water to a toilet bowl from a toilet tank
comprises a collapsible member configured to extend from the water
surface of water in the toilet tank down to the tank outlet in a
first or extended position. This extended position is maintained
when the flush valve is "closed," preventing the flow of water from
the resting toilet tank into the toilet bowl. The flush valve
maintains the level of water in the toilet tank by not allowing it
to flow into the toilet bowl. The flush valve may release water
from the toilet tank through the tank outlet by assuming a second
position in which the collapsible member of the flush valve is
longitudinally collapsed. The flush valve may be in the "relaxed"
position (meaning there are minimal, if any, spring forces acting
on the collapsible region of the flush valve collapsible member)
when the flush valve is extended in the toilet tank (the extended
position). Since the flush valve spends most of its useful lifetime
in the closed position, preventing toilet tank water from passing
into the toilet bowl, reducing spring forces on the flush valve may
substantially extend the lifetime of the flush valve. Further, the
flush valve collapsible member may comprise one or more materials
that do not substantially deteriorate in the presence of
halogen-containing toilet disinfectant solutions; for example,
rubbers, polymers, or combinations thereof which do not break down
or loose their material properties when exposed to
halogen-containing toilet disinfectants in a toilet tank for
extended amounts of time (e.g. weeks, months or years). Further,
the flush valve does not have a valve seat, as would be found in
flapper-type flush valves and other comparable flush valves.
[0012] In some versions, the flush valve collapsible member is
fabricated as a single, continuous piece. In some versions, all of
the outer surfaces of the flush valve that are exposed to toilet
tank water when the tank is full, and the valve is closed, are made
as a single piece. Thus, there are no (potentially leaky)
connections between separate components of the flush valve.
[0013] In some versions, the flush valve may also include at least
one ballast weight. Ballast weights may help overcome the forces
preventing the flush valve from collapsing to "open" and allow
passage of water from the toilet tank into the toilet bowl (e.g.
spring forces, material buoyancy, etc). In some version, ballast
weight may help apply force to collapse the flush valve. Because
the neutral position of the flush valve is in the extended (flush
valve closed) position, collapsing the flush valve may be
facilitated by ballast weights. The weights may be attached
anywhere on the flush valve, especially the upper region (closer to
the surface of the water in the toilet tank), for example, on the
bottom of the buoyant region of the flush valve.
[0014] In some versions, the flush valve collapsible member
comprises a base region, a float region, and a collapsible member
that are fabricated as a continuous single piece. Sinking the float
region allows the collapsible member to collapse and allows water
to flow through the collapsible member and out of the tank outlet
("opening" the flush valve). The collapsible region of the
collapsible member may be a collapsible bellows.
[0015] In some versions, the flush valve is opened by pushing on a
tipping actuator. Thus, the flush valve may include a tipping
actuator for sinking the float region of the flush valve.
[0016] In some versions, the base region, float region, and
collapsible member of the flush valve are fabricated as a single
piece by molding. In some versions, this molding is injection
molding. In other versions, this molding is blow molding.
[0017] In some versions, the collapsible member may have a
continuous spiral thread. For example, the "bellows" ridges of a
collapsible member may actually be one or more continuous ridges
spiraling around the outer edge of the collapsible region from the
top (near the water surface) to the bottom (near the tank outlet
port). The entire flush valve may be tapered (e.g. may be wider at
the top than the bottom), or just the collapsible member may be
tapered. Tapering may assist in fabricating the flush valve as a
single continuous piece. Similarly, the flush valve may be radially
symmetrical, which may also facilitate fabrication as a single
piece.
[0018] The flush valve may be fabricated from a polymer such as a
polyolefin. In particular, the flush valve may be fabricated from a
Very Low Density Polyethylene (VLDPE, for example, FLEXOMER
DFDA-1095 NT from DOW Chemical Company, or EXACT(.TM.) 5371 from
ExxonMobile Chemical), Ultra Low Density Polyethylene (ULDPE, for
example, ATTANE.RTM. 4404 G from DOW Chemical Company), or soft
vinyls (such as Tygon.RTM.).
[0019] In some versions, the flush valve further comprises a
longitudinal shaft coupled to the collapsible member (for example,
at the base region) wherein the shaft is configured to
substantially guide the flush valve when the collapsible member
collapses. The shaft may also include "stops" preventing the upper
opening into the flush valve from collapsing beyond a set position.
The shaft may be centrally positioned in the lumen of the flush
valve (e.g. positioned near the long axis of the flush valve) or
may be positioned off of the center (including external to the
lumen of the flush valve).
[0020] Also described herein are flush valves for controllably
delivering a selected amount of water to a toilet bowl from a
toilet tank, the toilet tank having a water surface and a tank
outlet, comprising a collapsible member configured to extend from
the water surface to the tank outlet in a first extended position
and to maintain the water in the toilet tank. The collapsible
member is further configured to release water from the toilet tank
through the tank outlet when it collapses longitudinally and takes
a second, collapsed, position. The flush valve collapsible member
comprises one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions. These flush valves also do not have a valve
seat. In one version, the collapsible member is fabricated as a
single continuous piece.
[0021] In one version of the flush valve, the collapsible member is
configured to be substantially relaxed in the extended position. In
some of these versions, the flush valve further comprises a ballast
weight. The flush valve collapsible member may comprise a base
region, a float region, and a collapsible member; sinking the float
region allows the collapsible member to collapse and allows water
to flow through the collapsible member and out of the tank
outlet.
[0022] In some version of the flush valve, the flush valve further
comprises a tipping actuator for sinking the float region of the
flush valve. In some versions of the flush valve, the base region,
float region, and collapsible member are fabricated as a single
piece by molding, for example, injection molding or blow
molding.
[0023] In some versions, the collapsible region of the flush valve
is a collapsible bellows; in some versions this collapsible bellows
has a continuous spiral thread (or ridge) at the bellows fold,
extending from the top of the flush valve to the bottom. In some of
these versions, the collapsible bellows is tapered.
[0024] The flush valve may be fabricated from a rubber, a polymer,
or a combination thereof. In one version, the flush valve is
fabricated from a polyolefin, in particular a Very Low Density
Polyethylene (VLDPE, for example, FLEXOMER DFDA-1095 NT from DOW
Chemical Company or EXACT(.TM.) 5371 from ExxonMobile Chemical),
Ultra Low Density Polyethylene (ULDPE, for example, ATTANE.RTM.
4404 G from DOW Chemical Company,), or soft vinyls (such as
Tygon.RTM.).
[0025] In some versions, the flush valve further comprises a
longitudinal shaft coupled to the collapsible member wherein the
shaft is configured to substantially guide the flush valve when the
collapsible member collapses.
[0026] Also described herein are flush valves for controllably
delivering a selected amount of water to a toilet bowl from a
toilet tank, the toilet tank having a water surface and a tank
outlet, comprising a collapsible member configured to extend from
the water surface to the tank outlet in a first extended position
and to maintain the water in the toilet tank. The flush valve is
further configured to release water from the toilet tank through
the tank outlet in a second, longitudinally collapsed, position.
The flush valve further comprises a ballast weight sufficient to
collapse the collapsible member.
[0027] In some versions, the flush valve also comprises one or more
materials that do not substantially deteriorate in the presence of
halogen-containing toilet disinfectant solutions. In some versions,
the collapsible member is fabricated as a single continuous piece
is configured to be substantially relaxed in the extended
position.
[0028] Also described herein are flush valves for delivering water
to a toilet bowl from a toilet tank comprising a base region
configured to connect to the outlet port of a toilet tank, a
floatable and sinkable float region having an opening that is held
above the surface of the water when the float region is floating,
and wherein the float region is linked to the base region through a
collapsible member extending from the base region to the float
region. The base region, float region and collapsible member are
fabricated as a single piece. Sinking the float region allows water
to flow through the opening of the float region and out of the
outlet port of the toilet tank. In some versions, the flush valve
further comprises a ballast weight. In some versions, the flush
valve further comprises a tipping actuator for sinking the float
region of the flush valve. In some versions, the collapsible member
is relaxed in the extended position.
[0029] In some versions, the flush valve may also include a flow
cone attached to upper region of the flush valve (e.g. the float
region) configured to modify the passage of water into the opening
of the float region.
[0030] Also described herein are flush valves for delivering water
to a toilet bowl from a toilet tank comprising a molding-formed
collapsible member configured to extend from the water surface to
the tank outlet in a first extended position and to maintain the
water in the toilet tank in this extended position. The flush valve
is further configured to release water from the toilet tank through
the tank outlet when the collapsible member of the flush valve
collapses into a second longitudinally collapsed position. This
version of the flush valve has a collapsible member that is
spirally threaded. Further, the flush valve has no valve seat. In
some versions this flush valve is tapered.
[0031] In some versions, the flush valve further comprises a
ballast weight. In some versions, the flush valve further comprises
a tipping actuator for sinking the float region of the flush valve.
In some versions, the collapsible member is relaxed in the extended
position.
[0032] Also described herein are methods of using the described
flush valve variations. In general, the flush valves described
herein may be used to provide water from a toilet tank into a
toilet bowl by at least partially sinking the flush valve. In some
versions, the flush valve is partially sunk by applying force (e.g.
by pushing) on a tipping actuator. In some versions, the tipping
actuator applies force to the upper portion of the flush valve
(e.g. a float region) to collapse the collapsible member of the
flush valve.
[0033] Also described herein are methods of using a flush valve
comprising at least partially sinking a float region of a flush
valve in a toilet tank having an outlet port in fluid connection
with a toilet bowl. The flush valve comprises a base region
configured to connect to an outlet port of the toilet tank, a
variably buoyant float region configured to switch between a high
buoyant state and a low buoyant state, and having an opening that
is held above the surface of the water when the float region is
highly buoyant, wherein the float region is linked to the base
region through a collapsible member extending from the base region
to the float region. The float region and the collapsible member
are fabricated as a single piece from one or more materials that do
not substantially deteriorate in the presence of halogen-containing
toilet disinfectant solutions.
[0034] Also described herein are methods of using a flush valve in
a toilet tank containing water comprising at least partially
sinking a flush valve. The flush valve comprises a collapsible
member configured to extend from the water surface to the tank
outlet in a first or extended position and to maintain the water in
the toilet tank, and the collapsible member is further configured
to release water from the toilet tank through the tank outlet in a
second, or longitudinally collapsed, position. The collapsible
member comprises one or more materials that do not substantially
deteriorate in the presence of halogen-containing toilet
disinfectant solutions, is fabricated as a single continuous piece.
The collapsible member is configured to be substantially relaxed in
the extended position.
[0035] Also described herein are methods of installing a flush
valve in a toilet tank, where the toilet tank has an outlet port in
fluid connection with a toilet bowl. The method of installing the
flush valve comprises providing a flush valve and installing the
flush valve onto the outlet port of the toilet tank. The flush
valve comprises a base region configured to connect to the outlet
port of a toilet tank, a variably buoyant float region configured
to switch between a high buoyant state and a low buoyant state, and
has an opening that is held above the surface of the water when the
float region is highly buoyant. The float region of the flush valve
is linked to the base region through a collapsible member extending
from the base region to the float region. The float region and the
collapsible member are fabricated as a single piece. In some
versions, the flush vale is installed by tightening a nut.
[0036] Also described herein are methods of fabricating a flush
valve comprising injection molding a flush valve. The flush valve
to be injection molded comprises a base region configured to
connect to the outlet port of a toilet tank, a variably buoyant
float region configured to switch between a high buoyant state and
a low buoyant state, having an opening that is held above the
surface of the water when the float region is highly buoyant,
wherein the float region is linked to the base region through a
collapsible member extending from the base region to the float
region. The float region, base region and the collapsible member of
the flush valve are injection molded as a single piece. In some
versions, the flush valve is injection molded from one or more
materials that do not substantially deteriorate in the presence of
halogen-containing toilet disinfectant solutions. In some versions,
the flush valve is tapered.
[0037] Also described herein are methods of fabricating a flush
valve comprising injection molding a collapsible member configured
to extend from the upper water surface of a substantially filled
toilet tank to the tank outlet in a first extended position to
maintain the water in the toilet tank, and further configured to
release water from the toilet tank through the tank outlet in a
second, longitudinally collapsed, position, wherein the collapsible
member is further configured to be substantially relaxed in the
extended position. The collapsible member is injection molded from
one or more materials that do not substantially deteriorate in the
presence of halogen-containing toilet disinfectant solutions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] Embodiments or variations are now described by way of
example with reference to the accompanying drawings.
[0039] FIG. 1 shows a schematic illustration of an integrated flush
valve;
[0040] FIG. 2 shows the flush valve of FIG. 1 in the collapsed
position;
[0041] FIGS. 3A to 3C show top views of the insides of the upper
float chamber;
[0042] FIG. 4 shows a schematic illustration of another version of
an integrated flush valve;
[0043] FIG. 5A shows an integrated flush valve having a tapered
bellows;
[0044] FIG. 5B shows an integrated flush valve;
[0045] FIG. 6 shows an integrated flush valve installed in a toilet
tank;
[0046] FIGS. 7A to 7C illustrate the activation of an integrated
flush valve.
DETAILED DESCRIPTION
[0047] Described here are integrated flush valves for use in toilet
tanks, methods of manufacturing the flush valves, and methods of
using the flush valves. In the drawings, reference numeral 10
generally denotes an exemplary embodiment of an integrated flush
valve. For the sake of brevity, an integrated flush valve will be
referred to as a "flush valve."
[0048] FIG. 1 shows a flush valve 10 in an extended position. The
flush valve is a collapsible member which comprises a hollow
integrated unit having regions corresponding to an attachment base
region 101 which attaches to the output port of a toilet tank (tank
outlet), a collapsible tube (or bellows or member) region 103 that
prevents the passage of water when extended and allows the passage
of water when the tube is collapsed, and a float region 105 which
may provide an upward buoyancy when the flush valve is in the
resting state. These regions of the flush valve are preferably
sub-regions of a single integrated component.
[0049] Because the flush valve in FIG. 1 is integrated, all of the
flush valve surfaces which contact fluid (e.g. water) in the
inactive state (when the valve is "shut") are continuous. Thus,
there is no need for seals or connections between the different
regions of the flush valve. This has many advantages over flush
valves which comprise separately joined regions, including cost and
durability. The fewer seals that a flush valve has, the less chance
it will leak. Further, flush valves with fewer components are
generally less expensive to produce than valves requiring the
assembly of multiple components.
[0050] The flush valve shown in FIG. 1 is formed as a single piece,
and thus does not have any joints or seals which may degrade and
potentially leak. The outer diameter of the flush valve provides
sufficient clearance to allow lateral ("up/down") movement within
the tank. As illustrated in FIG. 6, the outer surface of the flush
valve (shown in FIG. 1) is exposed to water in the toilet tank, and
acts as a barrier, preventing water in the toilet tank from flowing
into the tank outlet port until the flush valve is activated. The
inner region of the flush valve 109 is hollow, and forms a
continuous fluid connection with the outlet port of the toilet
tank.
[0051] FIG. 2 shows the flush valve of FIG. 1 in the longitudinally
collapsed position. The collapsible member of the flush valve 10
collapses to reduce the height of the flush valve. The change in
height may depend on the structure of the collapsible member. When
the collapsible tube is a bellows (as shown), the collapsible tube
height changes by folding, accordion-style. The collapsible tube
103 collapses when the float region loses buoyancy, for example,
when the float region is tilted and takes on water. Losing buoyancy
means that the upper, float region of the flush valve will sink,
allowing water to flow through the central channel of the flush
valve and out of the tank through the outlet port.
[0052] The inner region of the flush valve 109, may modify the
activity of the flush valve. In one version, the flush valve
includes inward radiating struts 301 to support a rod or shaft. The
inner region may also include additional attachment sites. In one
version, the inner diameter of at least a region of the flush valve
(e.g. the collapsible member) is optimized to increase the fluid
flow exit rate.
[0053] Attachment Base Region
[0054] The attachment base region 101 may attach into the tank in
the same way as would any standard flush valve attachment. In one
version, the attachment region attaches by a fixed elastomeric seal
compressed with a large plastic nut. Thus, the outer wall or the
inner wall of the attachment base region may be threaded or
otherwise textured to facilitate attachment to the outlet port of
the toilet tank.
[0055] The inner diameter of the attachment base region may be
adapted to modify the flow of liquid from the toilet tank, or it
may include supports or struts. Supports or struts may be useful to
provide enhanced strength for the attachment base region. Further,
supports or struts may be used to support a rod or shaft in the
flush valve. In one version, the inner diameter of the attachment
base region is narrower than other regions of the flush valve. In
one version, this narrowing of the inner diameter of the attachment
base region enhances the flow rate or pressure entering into the
toilet bowl.
[0056] The inner surface of the attachment base region may be an
integral part of the flush valve, or it may have additional
materials attached to it. The outer surface of the attachment base
region, as with the outer surface of the entire flush valve, is
preferably made as one single continuous piece.
[0057] In one version of the flush valve, the base region of the
flush valve comprises a sleeve which attaches to an attachment
adapter for sealing the base of the toilet tank to the tank outlet
port. An attachment adapter may include, for example, a threaded
nut adapter. In one version, one end of the threaded nut adapter is
attached to the base region of the flush valve. The threaded nut
adapter passes through the tank outlet port, and the nut is screwed
onto the threaded adapter on the opposite side. A water tight seal
is formed when the nut is tightened, forcing the base region of the
flush valve against the bottom and/or sides of the outlet port.
This type of attachment adapter works particularly well when the
base region is made of a compressible elastomeric material.
[0058] Flush valves as described above may be used with existing
("standard") toilet tanks. Thus, the outer diameter, thickness,
height and other dimensions of the attachment base region may be
adapted to fit the dimensions of any existing toilet tank,
particularly the outlet ports for the commercially available toilet
tanks. Of course, the dimensions of the attachment base region may
be adjusted to fit virtually any toilet tank output port.
[0059] In one version, the outer diameter, thickness and height of
the attachment base region are adapted to attach to a toilet tank
having an outlet port 2 inches in diameter. In one version, the
outer diameter thickness and height of the attachment base region
are adapted to attach tot a toilet tank having an outlet port 3
inches in diameter. The actual diameter of the outlet port may be
determined based on industry or government standards.
[0060] Collapsible Member
[0061] The collapsible member (collapsible tube region) 103 allows
the flush valve to change height by elongating or compressing
(collapsing) when the float region gains or loses buoyancy. In one
version, the collapsible tube is a bellows.
[0062] Preferably, the collapsible member is capable of undergoing
many thousands of compression/expansion cycles over a lifetime of
many years. The collapsible region collapses (contracts) each time
the flush valve is activated to allow fluid to flow out of the
flush valve. At the end of the flush cycle, the collapsible member
expands to prevent fluid from flowing out of the flush valve.
[0063] The structure of the collapsible member may be optimized for
durability, strength, and function. In one version, the wall
thickness of the collapsible member is substantially uniform. In
one version, the wall thickness is adjusted to accommodate the
repeated motions of the collapsible member; for example, by
reinforcing the parts of the collapsible member requiring greater
material strength.
[0064] The collapsible member of the flush valve shown in FIGS. 1
and 2 are bellows having one or more continuous ridges that coil
around the collapsible member. This results in a threaded
appearance. The dimensions of the "threads" in the collapsible tube
may, in part, determine how compressible the collapsible region is
(e.g. how far the flush valve collapses or changes its height). The
threaded collapsible member is particularly advantageous in
fabricating the integrated flush valve, as described below. A
collapsible tube region (or a region of a collapsible member of a
flush valve) having one or more continuous threads has one or more
ridges (threads) that begin at the top of the collapsible region
and continue to the bottom of the collapsible region. Thus, the
continuous thread(s) run, screw-like, around the collapsible
region. A continuous thread may be substantially continuous,
meaning that the thread may be interrupted (for example, by some
other structure) but then continue as if it had not been
interrupted.
[0065] In one version, the collapsible tube has two or more threads
forming the bellows. The threads are intertwined around the
perimeter of the collapsible tube and their starting points (e.g.
at the top or bottom of the collapsible member) may be equally
spaced from each other. Balancing the threads this way may prevent
unequal compression and torsion of the collapsible tube.
[0066] The dimensions of the collapsible member may vary depending
upon the design specifications. Thus, a fully extended collapsible
member should allow the upper surface of the flush valve to extend
beyond the maximum desirable tank fill level. The collapsed form of
the flush valve should place the opening of the collapsible member
of the flush valve at approximately the high of the completed tank
flush level. Thus, if a six liter flush is to be delivered, the
collapsible member should collapse at least to a height which will
deliver six liters of fluid. A selected amount of water can be
controllably delivered by the flush valve; for example by selecting
the height to which the flush valve collapses.
[0067] In some versions, the collapsible member will have a spring
modulus which may effect the operation of the flush valve. Thus, if
the collapsible member is a bellows, the dimensions and the
material chosen for the flush valve may, in part, determine the
spring modulus of the flush valve. In some cases, the spring
modulus describes the force required to move the collapsible member
either in expansion or compression. In one version, the spring
modulus is adjusted, for example, by the material used to form the
flush valve, or by treating the flush valve (e.g. by heat) to
pre-set the resting state of the collapsible tube.
[0068] In one version, the collapsible tube is substantially
extended in the neutral (relaxed) position. Thus, the collapsible
tube, and therefore the flush valve, relaxed in the extended
position in the filled toilet tank. In this extended state there
are minimal (or perhaps no) spring forces acting on the collapsible
tube. This "low stress neutral position" (or zero-stress neutral
position) may enhance the durability and lifetime of the flush
valve, as described further below. The "low stress neutral
position" is that position where movement of the collapsible member
along its axis, i.e., expanding or contracting, will exhibit a
positive or negative spring force. When the flush valve is
substantially extended, the collapsible region of the collapsible
member (flush valve) is extended longitudinally along the long axis
of the flush valve; in a water filled toilet tank the substantially
extended position is one in which the top portion of the
collapsible member is above the surface of the water.
[0069] In one version, the collapsible member of the flush valve is
tapered so that the inner diameter of the flush valve is greater in
the upper part of the collapsible member than it is in the lower
part of the collapsible member. For example, see FIG. 5A. Thus, the
collapsible member appears tapered. In one version, the collapsible
member is tapered and threaded.
[0070] Alternatively, the collapsible member may be a pliable
region. In one version, the collapsible member comprises a pliable
sheet formed into a collapsible member. In this version, the
collapsible member may be laterally supported by adding an
additional internal support, such as a spring or other framework.
Thus, although the collapsible member is sufficiently pliable to
collapse when the float region loses buoyancy and sinks, the
collapsible member is also sufficiently laterally supported to
prevent the fluid pressure from constricting the collapsible member
when the float region is buoyant. The outer (fluid-contacting
region) of the flush valve is a single continuous surface,
preventing leakage and the need for sealing the different regions
of the flush valve.
[0071] Although the collapsible tube is shown as substantially
cylindrical, the collapsible tube may be any cross-sectional shape,
including but not limited to, circular, elliptical, or polygonal
(e.g., triangular, square, etc).
[0072] Float Region
[0073] The float region of the collapsible tube provides upward
buoyancy to the flush valve. In the inactive state (when no fluid
flows into the flush toilet bowl through the flush valve), the
float region holds the opening of the flush valve above the surface
level of the water in the tank. In one version, the float region is
a captured open volume defined by a lower surface 131 and a side
rim 133, as shown in FIG. 1 and 2. The top rim 133 remains above
the surface of the waterline when the flush valve is inactive so
that no water leaves the flush valve from the toilet tank
unintentionally. In the neutral position, the buoyant force of the
float region overcomes the downward force of gravity (weight of the
flush valve) and any spring forces from the collapsible tube. In
one version, the collapsible tube has minimal spring forces in the
neutral position.
[0074] The dimensions of the outer parts of the float region (e.g.
the rim 133 and the lower surface 131) may vary, for example,
depending upon the materials chosen and the size of the tank in
which the flush valve is to be used. In one version, the rim 133
height is chosen to be relatively low so that the float region may
be readily tipped, making the flush valve sensitive to user
activation. In one version, the lower surface is larger to increase
buoyancy. In one version, the thickness of the rim and lower
surface are selected to enhance buoyancy while providing adequate
structural support.
[0075] FIGS. 3A to 3C show a top view of features of the inner
portion of the float region 105. In FIG. 3A, the center portion of
the float region interior contains an opening into the inner
chamber of the collapsible member 301, which is in fluid connection
with the tank outlet port through the attachment base region. In
one version, the opening 301 is surrounded by a rim 315. When the
flush valve is activated by tipping the float region, water will
enter the inner portion of the float region and reduce the
buoyancy, causing the float region to sink. A raised rim 315 slows
water from draining out of the float region into the collapsible
member, which may help sink the float region. The height of the rim
may vary. A taller inner rim means more water will be captured by
the float region after the valve is opened. The more water
captured, the greater the weight due to water to "sink" the float
region. The rim 315 may have one or more small openings to allow
water to eventually drain from the inner portion of the float
region. These openings help restore buoyancy at the end of the
flush valve open cycle, by allowing water to drain from the float
region.
[0076] FIG. 3B shows a version of the float region in which the
entrance to the collapsible member is partly occluded by support
320. The support 320 both modifies the flow through the flush valve
and may help support a shaft or rod. A rod or shaft may pass
through an opening 330 in the support 320. The dashed lines 303
indicate the location of the outer diameter of the collapsible
member beneath the lower surface of the float region. In one
version of the float region, the entrance to the collapsible member
contains struts.
[0077] In one version of the float region shown in FIG. 3B, a rim
322 surrounds the entrance into the collapsible member. The rim 322
in FIG. 3B narrows the opening (modifying the flow into the
collapsible member and out of the tank). The rim 322 is also raised
above the lower surface of the float region. The lower surface of
the float region may have holes 325 in the lower surface that empty
into the collapsible member to allow slow drainage of water from
the float region, for example, when restoring buoyancy.
Alternatively, or in addition, the rim may have drainage holes.
[0078] FIG. 3C shows a version of the float region in which a flow
cone has been added to modify the flow of water from the inner
portion of the float region into the collapsible member and out of
the flush valve. Beneath the flow cone (not shown) are holes in the
lower surface that allow the float region to empty (as in FIG. 3B
325). The flow cone may be of different heights and widths. In one
version, the flow cone has a curved surface to guide the water
flowing into the flush valve and through the tank outlet port. The
flow cone may be any height. In one version, the flow cone is low,
so that the top of the flow cone is near the lower surface of the
float region. In one version the flow cone is tall, so that the top
of the flow cone is at least halfway up the wall height of the
float region.
[0079] The overall shape of the float region 105 shown in FIGS. 1
to 3 is rectangular, however virtually any shape may be used. In
particular, a symmetric shape (e.g. round) may be desirable. FIG. 4
shows an example of a circular float region 401. In one version,
the float region is shaped to prevent contact with other parts of
the toilet tank, such as the refill inlet, the walls of the tank,
and the refill float.
[0080] The float region may also include adaptations for contact
with a tipping actuator. For example, the flush valve may be
actuated by tipping the float region so that it becomes at least
partly submerged. The float region of the flush valve may be tipped
by applying force to one or more parts of the float region. In one
version, a tipping actuator applies force against the upper surface
of part of the float region. In one version, float region includes
a contact (or "landing pad") specialization for contacting the
tipping actuator. In one version, the upper edge of the float
region is flanged to provide a more reliable contact region for the
tipping actuator. In one version, the tipping actuator is attached
to the float region.
[0081] In one version, the tipping actuator fits into a slot
located on the side or top portion of the float region. The slot
may be open at the top or may be closed, encircling the tipping
actuator. The slot may help guide the tipping actuator into
position with the float region of the flush valve. In one version,
the tipping actuator remains within the slot during the entire
flush cycle (as the flush valve collapses to open, and floats back
to the neutral position once buoyancy is restored).
[0082] Ballast Weights
[0083] The float region switches from buoyant (floating at the top
of the water in the tank) to non-buoyant (sinking to allow water
into the toilet bowl). The neutral buoyancy of the float region may
be modified by adding buoyant or non-buoyant weighting material
(weights). In one version, additional weight (e.g. ceramic plastic,
concretes, or metal weights) may be added to the float region. In
one version the weighting material is ballast. Weights maybe
adjustably added by a user or permanently affixed to the float
region. In one version, weights are added to the inside of the
float region. In one version, weights are added to the outside of
the float region. Buoyant material may also be added to increase
the buoyancy of the float region.
[0084] The density of the flush valve (e.g. the density of the
material from which the flush valve is fabricated) may determine
the weight of the flush valve. Most collapsible flush valves will
be fabricated of a material having a density near enough to that of
water so that when the flush valve is completely submerged, the
flush valve will not sink (collapse) unless there is at least one
additional force (e.g. spring forces, etc) acting on the
collapsible member of the flush valve. Thus, it may be desirable to
include ballast weight so that the flush valve will sink or
collapse to the proper stopping position in the toilet tank and
therefore empty the tank to an appropriate level.
[0085] In some versions of the flush valve, the collapsible member
is relaxed in the extended position. Ballast weights may be helpful
in these versions, particularly when the flush valve is composed of
a material having a density which is sufficiently near (or less
than) that of water. Thus, ballast weights, counterweights,
springs, or some combination may be assist the flush valve in
collapsing to the appropriate level from the relaxed (extended)
position.
[0086] In one version, weights are made of a water, corrosion
and/or chemically resistant material. For example, high density
plastics, metals, ceramics, concretes, or any combination thereof
may be used to make the weights. In on version, ceramics such as
porcelain or concrete materials are used. Weights may be affixed to
the float region passively (e.g. by sitting inside of the float
region) or actively (e.g. by fastening to the float region). In one
version, the float region includes a fastener at the bottom surface
of the float region to which a weight may be attached.
[0087] Guiding Rod
[0088] In one version the flush valve includes a rod or shaft 501.
FIG. 5B shows an example of a flush valve having a shaft 501
positioned in the long axis of the flush valve. The shaft attaches
to the center of the base unit 101 to provide vertical guidance for
the float and collapsible members of the flush valve. The shaft may
also help prevent excessive tipping by a tipping actuator when a
tipping actuator is used to trigger opening of the flush valve by
applying a force against one side of the float region. The shaft
may also engage with the upper region of the flush valve, though an
opening 330 in a support 320 at the base of the float region.
[0089] The shaft shown in FIG. 5B is centrally located, however a
guide shaft or rod may be positioned longitudinally anywhere it can
help stabilize and guide the longitudinal (e.g. collapsing) motion
of the flush valve. In one version the rod is located off-center in
the lumen of the flush valve. In one version, the rod is located
externally to the lumen of the flush valve. In one version, the
flush valve includes a pocket for inserting the guide rod.
[0090] The shaft may guide the movement of the opening and closing
of the flush valve. For example, the flush valve motion may be
limited by the shaft. In one version, the shaft is rigid, and
prevents excessive lateral motion of the flush valve. Thus, the
flush valve may be prevented from interfering with other components
in the toilet tank, for example. Some lateral (`tipping`) motion
may be desired, particularly when initiating opening of the flush
valve. Limited lateral motion may be permitted when the flush valve
includes a shaft, for example, by creating an opening through a
support 320 in the base of the float region which has a larger
diameter than the outer diameter of the shaft. In FIG. 3C, the
opening 330 for the shaft is elliptical, allowing tipping, but
limiting excessive lateral motion because of the guide rod which
has a circular outer diameter. Furthermore, tipping is permitted in
only the direction of the longer diameter of the elliptical opening
330.
[0091] A shaft may also limit vertical movement may of the flush
valve. In one version, the shaft has a vertical stop (e.g. a region
of greater diameter) preventing the float region from extending
past the top of the shaft. Additional stops may be located at other
regions on the shaft to limit the downward movement of the float
region of the flush valve. For example, the flush valve may be
prevented from falling to the bottom of the toilet tank in order to
limit the amount of fluid passed per flush.
[0092] A vertical stop may also prevent the toilet tank from
overflowing. If the water level in the tank fills above the upper
rim of the flush valve float region when the flush valve is kept
from extending further vertically by a vertical stop, the flush
valve will activate, flush the toilet tank and preventing overflow
of the tank.
[0093] In one version, the guiding shaft is hollow and allows water
to pass through the output port of the toilet tank without opening
the flush valve. In some versions, it may be desirable to pass a
small volume of water into the toilet bowl without opening the
flush valve, for example, when the tank is refilling following a
flush cycle. Water may be directed through the central channel of
the closed flush valve by an elbow joint connected to the tank
inflow valve. In one version, the guiding shaft is located within
the lumen of the flush valve and connected to the tank inflow
valve, allowing some water to pass through the flush valve as the
tank is refilling. The small amount of water passed into the tank
after the flush cycle may enhance toilet bowl re-filling. In one
version, the shaft is 0.5 inches in diameter, and has a wall
thickness of at least {fraction (1/16)}.sup.th of an inch.
[0094] Durability
[0095] Flush valves described and claimed here operate in the
water-filled toilet tank environment. In addition to water, the
toilet tank may comprise chemical, enzymatic, or other additives
(e.g. toilet bowl cleansers, deodorizers, etc.) which may
detrimentally effect any components of the toilet tank and toilet,
particularly the flush valve.
[0096] Further, the flush valve should operate over a reasonable
lifetime of a toilet tank. For example, a flush valve may operate
for at least a year, at least two years, at least five years, or at
least ten years.
[0097] A flush valve should operate reliably in the harsh toilet
tank environment. Thus, a flush valve should resist wear, handle
repeated use, and resist stress cracking, as well as be
substantially corrosion, water and/or chemically resistant.
Deterioration of the flush valve may result in loss of surface
integrity (e.g. cracking, tearing, or otherwise undesirably
allowing water to leak through the flush valve, etc.), or loss of
material strength (e.g. allowing regions of the flush valve to
collapse due to water pressure, etc.), or loss of material
characteristics (e.g. loss of flexibility during repeated
opening/closings, etc.).
[0098] Resistance to Mechanical Stresses
[0099] In one version, the flush valve resists mechanical stress
(e.g. cracking, creep and/or deformation) by minimizing the forces
acting on the flush valve in the neutral (closed) position. In one
version, the spring forces on the collapsible member are reduced or
eliminated when the collapsible tube is in the extended position
(the position that the collapsible tube would naturally be in when
the flush valve is closed). Thus, the collapsible tube at rest is
substantially extended. When the collapsible tube is collapsed, the
spring forces oppose the compression of the collapsible tube. Since
spring forces will only significantly act on the flush valve
collapsible tube when it is opened, material fatigue may be
decreased.
[0100] In the neutral state the toilet tank is lull of water, and
the flush valve is closed; the float region is substantially at the
surface of the water in the tank, and the collapsible member is
substantially extended so that the upper region of the flush valve
is held above the water surface. In practice, the majority of the
lifetime of an installed flush valve is spent in this position. The
float region and any weighting material (weights) displace a volume
of water whose weight is equal to the combined weight of the float
region and the weights in the neutral position. When the upper rim
of the float region is forced below the surface of the water in the
tank (e.g. by action of the tipping actuator), the float region is
flooded, and is now negatively buoyant because of the added weight
of the water in the float region. The negative buoyancy causes the
float region to descend, or sink, within the toilet tank, to a
predetermined stop position. Sinking the float region also causes
the collapsible member to compress. If the collapsible tube is
configured so that the spring force (e.g. material forces, etc) are
minimized when the flush valve is in the neutral position, then the
spring forces will be oppose the sinking of the float region when
the collapsible region collapses.
[0101] The degree to which the float region is negatively buoyant
is dependant upon the weight of the float region and any weighting
material (e.g. ballast weights) as well as the density of the float
region material, the weight of the flood water volume, and the
force exerted upon the float region by the collapsible member,
which varies with the position of the collapsible tube (e.g. spring
forces). The force of the water moving from the tank into the
central passage of the flush valve may also contribute a force
component. Water empties from the tank and into the toilet bowl
through the central passage of the negatively buoyant flush
valve.
[0102] The flushing action of the flush valve is completed when the
tank water level has been reduced so that the tank water level is
at the same height as the rim of the float region (now at its
lowest position), and after the residual flood water volume has
sufficiently drained into the throat of the central passage of the
flush valve. The float region then becomes positively buoyant as
the weight of the residual flood water is reduced. Once buoyancy is
restored, the float region of the flush valve rises in conjunction
with an increasing tank water level.
[0103] In one version, the flush valve is designed so that material
stresses acting on (and material fatigue of) the flush valve is
reduced or minimized. In particular, material stresses acting on
the collapsible member may be reduced or minimized, for example, by
optimizing the size and thickness of the threads in the
bellows-type collapsible tubes.
[0104] In general, the material chosen for all or regions of the
flush valve (e.g. the collapsible member) may be selected to effect
the mechanical properties (e.g. spring modulus) and durability of
the flush valve.
[0105] Resistance to Chemical Degradation
[0106] Chemicals and components added to toilet water may be
powerful corrosives or degrading agents which may otherwise reduce
the durability, performance and lifetime of the flush valve. Thus,
it is important that the flush valve, particularly the regions of
the flush valve exposed to toilet tank water when the valve is
closed, be resistant water and to some, most, or all of the
corrosive or degrading agents. Materials resistant to degrading
agents are materials that do not substantially deteriorate in the
presence of degrading agents (e.g. halogen-containing toilet
disinfectant solutions). Materials that do not
substantially-deteriorate will maintain flush-valve integrity (e.g.
prevent water from leaking through the flush valve); this includes
maintaining material strength and material characteristics of the
flush valve (e.g. flexibility and resistance to water
pressure).
[0107] In one version, at least the outer surface of the flush
valve comprises a material resistant to chlorine (Cl) containing
compounds, ions, or agents. Cl-containing ions, compounds or agents
include, but are not limited to, Cl.sup.-, percholorides,
chlorides, chlorates, percholorates, (e.g. hydrochloric acid,
hypochlorite bleach, trichloro-s-triazinetrione, etc.).
[0108] In one version, at least the outer surface of the flush
valve comprises a material resistant to bromine (Br) containing
compounds, ions, or agents. Br-containing ions, compounds or agents
include, but are not limited to, bromine, oxides of bromine,
hydrides of bromine, (e.g. sodium tetraborate pentahydrate,
etc).
[0109] In one version, at least the outer surface of the flush
valve comprises a material resistant to ingredients often present
in commercially available toilet water additives, such as bowl
cleaners, deodorants, etc. For example, the material comprising the
flush valve may be resistant to ingredients in (or produced by)
toilet water additives including isobomyl acetate, sodium
carbonate, sodium sulfate, hydroxyethyl cellulose, cocamide MEA,
sodium carbonate, FD&C Blue #1, sodium chloride, pine oil,
sodium dodecylbenzenesulfonate, sodium C.sub.14-C.sub.16 olefin
sulfonate, organic chlorine bleach, sodium tetraborate
pentahydrate, Acid Blue #9, aluminum sulfinate,
trichloro-s-triazinetrione, n-alkyl dimethyl benzyl ammonium
chlorides, n-alkyl dimethyl ethylbenzyl ammonium chlorides,
ammonium chlorides, isopropyl alcohol, sodium lauryl sulfate,
ammonium ions (e.g. at concentrations of from 0.05 to 2.5 ppm free
ammonia), and other halogen containing (and releasing) sanitizing
agents (such as N-halogenated organic compounds, e.g., brominated
phthalimides, p-toluene sulfonamides, azodicarbonamidines,
hydantoins, glycoluracils, cyanurates, amines, melamines,
N-chloro-phthalamide, N-bromo-phthalamide, N-dichloro-p-toluene
sulphonamide, 2,5-N,N'-dichloro-azodicarbonamidine hydrochloride,
N,N'-dichloro-dimethyl-hydantoin, N-bromo-N'-chlorodimethy-
l-hydantoin, N,N'-dibromo-dimethyl-hydantoin,
N-bromo-N-chloro-diphenyl-hy- dantoin,
bromocholoro-5,5-dimethylhydantonin, 1,3-dichloro-5-ethyl-5-methy-
lhydantonin, 1,3-dibromo-5,5-dimethylhydantoin (DBDMH),
1,3-dichloro-5,5-dimethylhydantoin (DCDMH),
1-bromo-3-chloro-5,5-dimethyl- hydantoin (BCDMH),
dichloroisocyanuric acid and its sodium and potassium salts,
trichloroisocyanuric acid (TCICA), hypochlorite ion-releasing
agents (e.g., calcium hypochlorite and lithium hypochlorite,
N,N,N,N-tetrachlorodimethyl-glycoluracil,
N-bromo-N,N-dichloro-dimethylgl- ycoluracil,
N,N'-dibromo-dimethyl-glycoluracil, N,N,N,N-tetrachloro-glycol-
uracil, N,N-dichlorodichloroyl, N-bromo-N-chloro-sodium cyanurate,
dibromo triethylene diamine dihydrochloride,
bromo-chlorotriethylene diamine dihydrochloride and
N,N,N-trichloro-melamine).
[0110] Of special interest are materials that have long-term
resistance to chemicals used in resident toilet disinfectant
compositions, which are often made into pills, pellets, or the like
and placed in the toilet tank for extended periods. These
compositions usually release chlorine (or other halogens) and
related materials over extended lengths of time. For instance, many
such compositions include as active disinfectant and cleansing
components, halogen-releasing agents such as chloramines;
chlorimines; chloramides; chlorimides; halogenated isocyanurates,
including heterocyclic N-bromo and N-chloro cyanurates; halogenated
melamines such as N,N,N-trichloromelamine; N-chlorosuccinimide;
alkali metal or alkaline earth metal hypochlorites, e.g., calcium
hypochlorite and lithium hypochlorite; halogenated phthalamides
such as N-chloro-phthalamide and N-bromophthalamide; and the
halogenated hydantoins, particularly halogenated
5,5-dialkyl-substituted hydantoins. Examples of particular
hydantoins found in residential toilet disinfectants include
1-bromo-3-chloro-5,5-dimethylhydantoin,
1,3-dichloro-5,5-dimethylhydantoin,
1,3-dibromo-5,5-dimethylhydantoin,
1-bromo-3-chloro-5,5-diethylhydantoin,
1,3-dichloro-5,5-diethylhydantoin,
1,3-dibromo-5,5-diethylhydantoin,
1-bromo-3-chloro-5-methyl-5-ethylhydant- oin,
1,3-dichloro-5-methyl-5-ethylhydantoin,
1,3-dibromo-5-methyl-5-ethylh- ydantoin,
1-bromo-3-chloro-5-methyl-5-n-propylhydantoin,
1,3-dichloro-5-methyl-5-n-propylhydantoin,
1,3-dibromo-5-methyl-5-n-propy- lhydantoin, and the like.
[0111] Toilet cleaning agents may release (typically at a
controlled, substantially constant, rate) halogens into the tank
water at a concentration in the range of 0.5 to 5 ppm perhaps with
values of pH ranging of from about 6.5 to about 10, over its entire
life of 2 to about 4 months of constant contact with water. A
single block may deliver a uniform level of halogen (0.5-3 ppm) for
about 1700 to 2100 flushes and will be completely dissolved at the
end of its useful life.
[0112] In one version of the flush valve, the fluid-contacting
surfaces of the flush valve comprise a material or materials
substantially resistant to the toilet water chemical additives.
Examples of such appropriate resistant materials are described
below in the section titled "Materials," and may include
polyolefins.
[0113] In one version, at least the outer surface of the flush
valve comprises a material resistant to enzymes. In one version, at
least the outer surface of the flush valve comprises a material
resistant to amines. In one version, at least the outer surface of
the flush valve comprises a material resistant to borax.
[0114] Fabrication
[0115] The flush valve described herein may be fabricated as a
single continuous piece, for example, by injection molding or
blow-form molding. In particular, fabrication of a single
continuous piece means that all (or most) of the surfaces of the
flush valve that contact water when the flush valve is "closed" in
a filled toilet tank are a single integrated piece (e.g., without
seals or connectors). Minimizing the number of components of the
flush valve reduces the cost, and complexity and likelihood of
failure or leakage of the flush valve. In one version, the flush
valve base region, collapsible member and float regions are all
regions of a single piece such that these three regions do not
require further connecting or seals. In one version, the base
region and the collapsible member are fabricated as a single piece
that does not require further connection or seals. In one version,
the collapsible member and the float region are fabricated as a
single piece that dose not require further connection or seals.
[0116] In one version, the flush valve is injection molded. In
general, injection-molding involves the steps of: (a) feeding a
composition into the heating chamber of a molding machine and
heating the composition to form a molten composition; b) injecting
the molten composition into a mold cavity; c) maintaining the
composition in the mold under high pressure until it cools; and d)
removing the molded article.
[0117] In one version of the flush valve, flush valve is tapered to
facilitate removal of the flush valve from the mold. In one
version, the injection mold has a central core for shaping the
inner surface of the flush valve. Bellows-type structures, such as
the collapsible member of some versions of the flush valve, are
difficult to remove from a central core of an injection mold once
formed. However, when the collapsible tube is configured as a
continuous "screw" shape (as described above), the collapsible
member of the flush valve may be formed between the walls of an
injection mold, and later "unscrewed" to remove the central mold
core.
[0118] FIG. 5A shows a flush valve which is formed as a single
piece. The flush valve of FIG. 5A has a number of features which
facilitate fabrication by a molding technique such as injection
molding. First, the collapsible member 103 has one or more threads
501 which extend from the upper portion all the way to the base
region 101. Thus, the flush valve may be "unscrewed" from the
central region of a mold. Second, the collapsible member of the
flush valve shown in FIG. 5A is tapered. The inner diameter of the
flush valve generally decreases from the bottom of the flush valve
to the top of the flush valve (from the base region to the float
region). Tapering makes removal from a central region of a mold
easier; particularly when combined with the threaded collapsible
tube design described above. In threaded and tapered versions of
the flush valve, the central core of a mold can be withdrawn after
unscrewing the collapsible member even a short distance (e.g. a
quarter of a rotation). Finally, the flush valve of FIG. 5A is
substantially radially symmetrical, further facilitating removal of
the central region of a mold. Radial symmetry allows a central mold
to be loosened by rotation, a feature that is particularly helpful
when the collapsible region of the flush valve is threaded.
[0119] Any of the features described above for the version of the
flush valve shown in FIG. 5A may be used alone or in combination
with other features to facilitate fabrication of the flush
valve.
[0120] The flush valve described herein may be fabricated by any
method capable of creating an integrated flush valve. Thus,
variations and modification of the general injection molding
technique described above are contemplated, including but not
limited to reactive injection molding, rotational molding,
thermoforming, vacuum molding, blow molding, gas-assist or
water-assist injection molding, etc.
[0121] Once a flush valve is fabricated, it may be treated or
further processed. It is desirable to minimize amount of
post-molding processing that a flush valve undergoes, to simplify
the fabrication process and to reduce the cost of fabrication.
Example of post-fabrication processing includes but is not limited
to: cutting, shaping, heating, baking, coating, and connecting to
additional components.
[0122] In one version, the flush valve is treated after fabrication
to set the neutral (relaxed) shape of the collapsible member by
expanding or compressing the collapsible member and applying
heating to reset the shape. In some versions, the flush valve is
fabricated so that the collapsible member is substantially extended
in the neutral position.
[0123] In one version of the flush valve, the outer surface of the
flush valve is fabricated as a single piece, by injection
molding.
[0124] Materials
[0125] The flush valve or its components may be made of one or more
materials capable of withstanding the environment of the toilet
tank while maintaining the integrity of the outer (fluid
contacting) surface after many opening/closing cycles of the flush
valve. For instance, useful materials include various polymers
(including thermoplastics and thermoset plastics), rubbers, and
mixtures thereof. Of particular value are moldable thermoplastics.
Examples of useful polymers include, but are not limited to
polyolefins, such as polyethylenes (e.g. Very Low Density
Polyethylene (VLDPE), Ultra Low Density Polyethylene (ULDPE),
plastomers, etc., particularly those having a density between about
0.86 to about 0.92 g/cc), polypropylenes, chlorinated vinyl resin
selected from the group consisting of polyvinyl chloride,
postchlorinated polyvinyl chloride, polyvinylidine chloride and
copolymers thereof, and chlorinated rubbers, polyvinyl chlorides
(e.g. soft vinyls such as Tygon.RTM.), and mixtures thereof, such
as thermoplastic elastomers (e.g. thermoplastic vulcinates and
other blends of polypropylene and/or polyethylene with rubbers,
etc.).
[0126] In one version, the outer surface of the flush valve is made
of a material which is corrosion and/or degradation resistant. As
described above, it is beneficial that the flush valve be made of a
material that is resistant to chemicals present or added to toilet
water, such as chlorines, bromines, enzymes and amines, etc.
(including those described above in the section entitled
"Resistance to Chemical Stress"). In one version, the outer surface
of the flush valve is made of a material that is can be readily
fabricated. In one version, the outer surface of the flush valve is
made of a material that can be fabricated by injection molding.
[0127] In one version, the flush valve is comprised of a material
which has a modulus of between about 300 and 3000 psi. In one
version, the flush valve is comprised of a material having a high
environmental stress crack resistance (ESCR). In one version, the
flush valve is comprised of a material having a high fatigue
life.
[0128] In one version, the flush valve is comprised of a material
having an operating temperature range of between about 32 and
120.degree. F. In one version, the flush valve is comprised of a
material having a low modulus change over a temperature range of
between about 32 and 120.degree. F.
[0129] In one version, the flush valve is comprised of a material
that is readily moldable. In one version, the flush valve is
comprised of a material that is readily blow moldable. In one
version, the flush valve is comprised of a material that is readily
injection moldable. In one version, the flush valve is comprised of
a material that is readily blow moldable and injection moldable. In
one version, the flush valve is comprised of a material that has a
melt index above about 3. In one version, the flush valve is
comprised of a material that has a melt index of approximately
10.
[0130] In one version, the flush valve is comprised of a material
that has a relatively high toughness. In one version, the flush
valve is comprised of a material that has a relatively high
abrasion resistance. In one version, the flush valve is comprised
of a material that has a relatively high puncture resistance.
[0131] Examples of thermoplastic materials are acetals, acrylics,
cellulose acetates, the Nylons, polyolefins (such as polyethylene,
polypropylene, polybutylene, t-butylene, their mixtures, alloys,
and mixed copolymers and block copolymers), polystyrene, vinyl, and
nylon amino, polycarbonate, polystyrene, ABS
(acrylonitrile-butadiene-styrene), SAN (styrene-acrylonitrile), and
PVC (polyvinylchloride). Thermoplastic elastomers (TPEs) may be
particularly desirable. Thermoset materials include amino, epoxy,
phenolic, and unsaturated polyesters. Thermoplastic Polyolefin
Elastomers (TPOs) are also desirable. Characteristics of plastics
materials can be changed by mixing or combining different types of
polymers and by adding non-plastics materials such as particulate
fillers and plasticizers.
[0132] Examples of rubber materials that may be used include, but
are not limited to halogen-free diene rubbers, hydrogenation
products of halogen-free diene rubbers, acrylic rubbers,
epichlorohydrin rubbers, olefin rubbers, halogen-containing
rubbers, silicone rubbers, pure rubbers, fluorinated rubbers, and
fluorinated blends, etc. Mixtures of rubbers, and polymers may also
be useful.
[0133] Examples of polyolefins and polyolefin copolymers that may
be used include VLDPEs (for example, FLEXOMER DFDA-1095 NT from DOW
Chemical Company, ExxonMobil EXACT resin 5371), ULDPE (for example,
ATTANE 4404 G from DOW Chemical Company), bimodal polyethylene
resin (e.g., Dow CONTINUUM), HDPE, LLDPE and polypropylene.
Examples of soft vinyls that may be used include Tygon.RTM..
[0134] The flush valve may also be coated with a material which
provides protection or other advantages. For example, suitable
coatings may improve resistance to corrosion and swelling, and
otherwise enhance durability. Examples of coatings may include but
are not limited to hydrophobic coatings (e.g. wax), polymeric
coatings (e.g. Ethylene vinyl alcohol, etc.), and rubbery coatings
(e.g. Silicones).
[0135] The flush valve may be colored or transparent. Although the
color of the flush valve does not substantially affect the
function, the flush valve may be made to have an aesthetically
pleasing color, for example, by dying, painting, coating, etc.
[0136] Installation
[0137] A flush valve as described herein may be installed into the
tank of a toilet by attaching the base region of the flush valve to
the tank outlet port. In one version, the flush valve is attached
to the outlet port by inserting the base region of the flush valve
through the tank outlet port, and attaching applying pressure to
seal the base region of the flush valve to the sides of the toilet
outlet port. In one version, the base of the outlet port is
threaded to attach to a nut. In versions of the flush valve in
which the base of the flush valve is made of an elastomeric
material, the flush valve may be sealed in the outlet port by
clamping the base region of the flush valve against the tank, e.g.
the sides of the outlet port. In one version, the flush valve is
clamped to the outlet port by tightening a nut which compresses the
base region of the flush valve against the walls of the outlet
port. In one version, the inside of the base region of the flush
valve threaded, and the base region of the flush valve is inserted
into the tank outlet port and a threaded cylinder can be screwed
into the base region to apply pressure sufficient to seal the base
region into the tank outlet port. The threaded cylinder may be
tapered so that the base region is slightly expanded as the
cylinder is tightened, enhancing the seal.
[0138] The tank outlet port should be in fluid communication with
the toilet bowl, so that fluid passing through the tank outlet port
will enter the toilet bowl.
[0139] Operation
[0140] FIG. 6 illustrates an example of a flush valve installed in
a toilet tank. In FIG. 6, the tank portion of the toilet is show
partly cut away, revealing the water 601, flush valve 10, tipping
actuator 605, and refilling inflow valve 607. The flush valve 10 is
attached to the tank outlet port 611 at the base region of the
flush valve, preventing water from entering the toilet bowl 620.
The float region of the flush valve is buoyantly held above the
surface of the water. The tipping actuator 605 in FIG. 6 is a rigid
member attached to a handle 615. The end of the tipping actuator is
on or above the edge of the top of the float region of the flush
valve. Moving the handle 615 moves the tipping actuator, and thus,
pushes down on the edge of one side of the flush valve, opening the
flush valve.
[0141] The tipping actuator may be configured so that moving the
handle on the outside of the toilet tank 615 downwards (as in most
standard US toilet tanks) opens the flush valve. The tipping
actuator may also include a spring, buoyant material,
counterweight, or some combination thereof to return the actuator
to the rest position immediately after flushing the toilet.
[0142] Although the tipping actuator is shown as a rigid member
that may be pivoted by moving the handle, the tipping actuator may
be any device capable of submerging at least one edge of the float
region of the flush valve. The tipping actuator may submerge the
entire float region. Thus, the tipping actuator may be a chain,
lever arm, or plunger. It is preferable that the tipping actuator
be controlled by the user from the side of the tank, for example by
a handle means, as shown in FIG. 6. As will be apparent to those in
the art, the handle means may be located anywhere on the toilet
tank, including the top and sides. In addition to the components
shown in FIG. 6, a toilet using a flush valve as described herein
may include additional components, or other versions of the
components shown in the FIG. 6. For example, the refilling inflow
valve 607 may include a different float valve for detecting the
fill level of the tank. An elbow joint may be attached to the
inflow valve to apply water directly down the flush valve when the
tank is being refilled.
[0143] FIG. 7A to 7C shows the flush valve being opened. In FIG.
7A, the flush valve is closed, but poised for activation by the
tipping actuator 605. The collapsible flush valve is in the neutral
position, fully extended. The tank is full of water 703, which is
prevented from exiting the output port of the tank by the walls of
the flush valve 10. In FIG. 7B the tipping actuator has been moved
from its neutral resting position above (or on) the upper edge of
the float region of the flush valve so that it contacts an edge of
the float region of the flush valve. The tipping actuator applies
sufficient force to the float region of the flush valve to overcome
the buoyant forces keeping the float region above the water, and
submerging at least part of the float region. Once the float region
takes on water (as shown), the weight of the water also counteracts
the buoyant forces of the float region, and top (float region) of
the flush valve drops down towards the bottom of the tank as shown
in FIG. 6C. The collapsible member of the flush valve collapses to
permit the flush valve to sink. Water from the tank enters the
flush valve, and drains out to the toilet bowl. Thus, the
collapsible member of the flush valve collapses from the neutral
extended position into the collapsed state.
[0144] The flush valve is turned off once the water in the tank has
drained to a level approximately equal to the top of the float
region, and the float region can no longer sink. Buoyancy of the
float region is fully restored once the water in the float region
(which is weighing down the float region) drains into the flush
valve. As the tank is refilled through the tank inlet valve, the
float region rises with the surface of the water in the tank. After
the tank is completely refilled, the float region of the flush
valve is once again at the top of the water level, and the flush
valve is fully closed, and ready to be activated by the tipping
actuator.
[0145] Although illustrative variations of the flush valve have
been described above, it will be evident to a skilled artisan that
various changes and modifications may be made without departing
from the true scope and spirit of the flush valve described above
and herein claimed. The various examples are, therefore, to be
considered in all respects as illustrative and not restrictive.
* * * * *