U.S. patent application number 13/574479 was filed with the patent office on 2012-11-15 for drainage channel of flush toilet.
This patent application is currently assigned to LIXIL CORPORATION. Invention is credited to Takamasa Ina, Akinori Kamiya, Gousuke Sakakibara, Teruhiro Yamada.
Application Number | 20120284911 13/574479 |
Document ID | / |
Family ID | 46751674 |
Filed Date | 2012-11-15 |
United States Patent
Application |
20120284911 |
Kind Code |
A1 |
Kamiya; Akinori ; et
al. |
November 15, 2012 |
DRAINAGE CHANNEL OF FLUSH TOILET
Abstract
Disclosed is a flush toilet drainage channel capable of good
flushing. The flush toilet drainage channel includes an ascending
channel (30) which communicates with the downstream side of a
toilet bowl (10) and ascends toward the downstream side. The
ascending channel (30) is formed so that a channel bottom (33) is
gradually rendered wider toward a bottom top (32) thereof located
at the downstream side.
Inventors: |
Kamiya; Akinori; (Tokyo,
JP) ; Yamada; Teruhiro; (Inuyama-shi, JP) ;
Sakakibara; Gousuke; (Chita-gun, JP) ; Ina;
Takamasa; (Tokyo, JP) |
Assignee: |
LIXIL CORPORATION
Tokyo
JP
|
Family ID: |
46751674 |
Appl. No.: |
13/574479 |
Filed: |
January 28, 2011 |
PCT Filed: |
January 28, 2011 |
PCT NO: |
PCT/JP2011/051736 |
371 Date: |
July 20, 2012 |
Current U.S.
Class: |
4/420 |
Current CPC
Class: |
E03D 2201/40 20130101;
E03D 11/08 20130101; E03D 11/18 20130101 |
Class at
Publication: |
4/420 |
International
Class: |
E03D 11/00 20060101
E03D011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 1, 2010 |
JP |
2010-020790 |
Dec 15, 2010 |
JP |
2010-279720 |
Dec 15, 2010 |
JP |
2010-279722 |
Dec 15, 2010 |
JP |
2010-279723 |
Dec 28, 2010 |
JP |
2010-294318 |
Claims
1. A drainage channel of a flush toilet, comprising an ascending
channel which communicates with a downstream side of a toilet bowl
and ascends toward a downstream side of the drainage channel,
wherein the ascending channel is formed so that a channel bottom of
the ascending channel is gradually rendered wider toward a bottom
top thereof located at the downstream side of the drainage
channel.
2. The drainage channel according to claim 1, wherein the bottom
top has a substantially horizontal surface extending in a direction
perpendicular to a drainage direction of flushing water.
3. The drainage channel according to claim 1, wherein the ascending
channel includes an upstream end, a vertical middle, a first region
between the upstream end and the vertical middle and a second
region between the middle and an upstream side of the bottom top,
and the ascending channel has a cross-sectional shape in a
direction perpendicular to the, drainage direction of the flushing
water; in the cross-sectional shape of the ascending channel, the
first region includes a first upper region and first lower region
both relative to the vertical middle, and the first upper region
has a larger flow passage area than the first lower region; and in
the cross-sectional shape of the ascending channel, the second
region includes a second upper region and a second lower region
both relative to the vertical middle, and the second lower region
has a larger flow passage area than the second upper region.
4. The drainage channel according to claim 1, wherein the channel
bottom of the ascending channel has a substantially flat surface
extending in a/the drainage direction of the flushing water and in
a direction perpendicular to the drainage direction.
5. The drainage channel according to claim 1, wherein the ascending
channel has a vertical maximum length that is enlarged from the
upstream end toward the downstream side in a/the cross-sectional
shape of the ascending channel in the direction perpendicular to
the drainage direction of the flushing water.
6. The drainage channel according to claim 5, wherein the ascending
channel has an upper surface formed into an angled shape such that
the upper surface is gradually enlarged from a middle part thereof
toward right and left lower parts thereof in the cross-sectional
shape of the ascending channel in the direction perpendicular to
the drainage direction of the flushing water.
7. The drainage channel according to claim 1, further comprising a
descending channel communicating with a downstream side of the
ascending channel and descending toward the downstream side of the
drainage channel, the descending channel having a ledge extending
from the bottom top of the ascending, channel to inwardly protrude
along an inner periphery of the descending channel.
8. The drainage channel according to claim 7, wherein the ledge is
formed into an inclined surface directed inwardly upward.
9. The drainage channel according to claim 7, wherein the
descending channel has a rear surface and the ledge extends, near a
middle part of the rear surface of the descending channel.
10. The drainage channel according to claim 7, wherein the ledge
descends rearward along the inner peripheral surface of the
descending channel.
11. A drainage channel of a flush toilet, comprising an ascending
channel which communicates with a downstream side of a toilet bowl
and ascends toward a downstream side of the drainage channel,
wherein the ascending channel has a cross-sectional shape in a
direction perpendicular to the drainage direction of the flushing
water; and in the cross-sectional shape, the ascending channel has
a vertical maximum length that is increased from the upstream end
toward the downstream side and the upstream end has an inner
surface having a larger crosswise dimension than a longitudinal
dimension.
12. The, drainage channel according to claim 1, wherein the
ascending channel has an upper surface formed into an angled shape
such that the upper surface is gradually enlarged from a middle
part thereof toward right and left lower parts thereof, in a/the
cross-sectional shape of the ascending channel in the direction
perpendicular to the drainage direction of the flushing water.
13. The drainage channel according to claim 12, wherein the channel
bottom of the ascending channel has rising surfaces rising from
right and left ends thereof, and the rising surfaces have maximum
heights near an upstream side of the bottom top located at the
downstream side of the drainage channel, respectively, in the
cross-sectional shape perpendicular to the drainage direction of
the flushing water.
14. The drainage channel according to claim 12, wherein the upper
surface of the ascending channel is formed into an inclined surface
extending from a middle part thereof rightward downward and
leftward downward and inwardly swollen, in the cross-sectional
shape perpendicular to the drainage direction of the flushing
water.
15. The drainage channel according to claim 1, wherein the
ascending channel has corners between the channel bottom and the
rising surfaces rising from the right and left ends of the channel
bottom near the upstream end of the ascending channel respectively;
the corners are formed into respective rounded surfaces; and the
rounded surface of one of the right and left corners has a larger
curvature than the rounded surface of the other corner.
16. The drainage channel according to claim 1, further comprising a
pipe-like introduction passage downwardly inclined from a lower end
of the toilet bowl toward the upstream end of the ascending
channel.
17. A drainage channel of a flush toilet, comprising a descending
channel which communicates with a downstream side of an ascending
channel communicating with a downstream side of a toilet bowl and
ascending toward a downstream side of the drainage channel, the
descending channel descending toward the downstream side, wherein
the descending channel has a ledge which extends from a bottom top
located at a downstream side of a channel bottom of the ascending
channel and is formed so as to inwardly protrude along an inner
periphery of the descending channel.
18. The drainage channel according to claim 17, wherein the ledge
descends rearward along the inner periphery of the descending
channel.
19. The drainage channel according to claim 17, wherein the ledge
is formed into an inclined surface directed inwardly upward.
20. The drainage channel according to claim 17, wherein the
descending channel has a rear surface and the ledge extends near a
middle part of the rear surface of the descending channel.
21. The drainage channel according to claim 11, wherein the
ascending channel has an upper surface formed into an angled shape
such that the upper surface is gradually enlarged from a middle
part thereof toward right and left lower parts thereof, in a/the
cross-sectional shape of the ascending channel in the direction
perpendicular to the drainage direction of the flushing water.
22. The drainage channel according to claim 11, wherein the
ascending channel has corners between the channel bottom and the
rising surfaces rising from the right and left ends of the channel
bottom near the upstream end of the ascending channel respectively;
the corners are formed into respective rounded surfaces; and the
rounded surface of one of the right and left corners has a larger
curvature than the rounded surface of the other corner.
23. The drainage channel according to claim 11, further comprising
pipe-like introduction passage downwardly inclined from a lower end
of the toilet bowl toward the upstream end of the ascending
channel.
Description
TECHNICAL FIELD
[0001] The present invention relates to a drainage channel of a
flush toilet.
BACKGROUND ART
[0002] Patent Document 1 discloses a conventional drainage channel
of a flush toilet. The disclosed drainage channel includes an
ascending channel communicating with a downstream side of a toilet
bowl and ascending toward the downstream side and a descending
channel communicating with the ascending channel and descending
toward the downstream side. The ascending channel has a top located
at the downstream side and including a horizontal surface extending
in a direction perpendicular to a drainage direction of flushing
water. The top of the ascending channel has a width that is as
large as or larger than the other part of the ascending channel.
Accordingly, the drainage channel can increase an amount of
flushing water flowing over the top with increase in a water
level.
[0003] This drainage channel further includes a ledge comprising an
inclined surface directed inwardly upward and located in a boundary
between the descending channel and a bottom top located at the
downstream side of a channel bottom of the ascending channel.
Accordingly, a large amount of flushing water having flowed at an
initial stage of toilet flushing flows downward into the descending
channel so as to be peeled from an inner periphery of the
descending channel by the ledge. The flushing water collides
against the rear inner periphery of the descending channel opposed
to the ledge, whereupon a water screen can be formed in the
descending channel. Consequently, a siphon action is caused in a
drainage channel of the flush toilet with the result that toilet
flushing can be executed.
[0004] Furthermore, Patent Document 2 discloses another
conventional drainage channel of a flush toilet. The disclosed
drainage channel includes an ascending channel communicating with a
downstream side of a toilet bowl and ascending toward the
downstream side and a descending channel communicating with the
ascending channel and descending toward the downstream side. The
ascending channel has an upstream end that has a smallest flow
channel area in the drainage channel. The ascending channel is
formed so that a flow passage area is rendered gradually larger
toward the downstream side. Accordingly, when a large amount of
waste or the like is excreted into the toilet bowl, the waste or
the like can be caught by the upstream end of the ascending channel
to thereby be prevented from clogging the ascending channel.
PRIOR ART DOCUMENT
Patent Documents
[0005] Patent Document 1: Japanese Patent Application Publication
No. JP-A-H07-324367
[0006] Patent Document 2: Japanese Patent Application Publication
No. JP-A-H08-232330
SUMMARY OF THE INVENTION
Problem to Be Overcome By the Invention
[0007] However, the shape of the ascending channel leading to the
top is not considered in the drainage channel of Patent Document 1.
As a result, even upon occurrence of a siphon action, flushing
water would not desirably flow through the ascending channel
depending upon the shape of the ascending channel. In this case,
there is a possibility that waste or the like cannot be conveyed
with water successfully.
[0008] Furthermore, when a flow rate of flushing water flowing over
the top is low or when a force of the flushing water is small,
there is a possibility that the flushing water cannot be delivered
to the rear of an inner periphery of the descending channel opposed
to the ledge. In this case, since no water screen is formed in the
descending channel, the siphon action cannot be caused in the
drainage channel, whereupon flushing becomes insufficient in the
flush toilet.
[0009] Since the upstream end of the ascending channel in the
drainage channel of Patent Document 2 has a small flow passage
area, flushing water cannot be caused to smoothly flow fast.
Furthermore, since the ascending channel has a flow passage area
that is gradually increased toward the downstream side, a turbulent
flow tends to occur easily and resistance occurs accordingly,
whereupon it is difficult to cause waste to smoothly flow with
water through the drain channel. Additionally, since the upstream
end of the ascending channel has a small flow passage area as
described above, the ascending channel has a possibility of being
clogged with waste or the like at the upstream end.
[0010] The present invention was made in view of the
above-described circumstances in the conventional technique and an
object thereof is to provide a drainage channel of the flush
toilet, which can successfully perform toilet flushing.
Means for Overcoming the Problem
[0011] A drainage channel of a flush toilet, according to the
present invention, comprises an ascending channel which
communicates with a downstream side of a toilet bowl and ascends
toward a downstream side of the drainage channel, wherein the
ascending channel is formed so that a channel bottom of the
ascending channel is gradually rendered wider toward bottom top
thereof located at the downstream side of the drainage channel.
[0012] The inventors have found that a flow speed of flushing water
near the channel bottom of the ascending channel is lower at the
upstream side due to changes in the drainage direction of flushing
water from a downward direction to an upward direction at the
upstream end of the ascending channel, and the flushing water tends
to stagnate, and a flow speed of flushing water is higher at the
downstream side than at the upstream side. The inventors have also
found that a flow speed of flushing water near the upper surface of
the ascending channel is higher in the neighborhood of the upstream
end but is lower at the downstream side, whereupon the flushing
water tends to stagnate.
[0013] Accordingly, the bottom of the ascending channel is
gradually rendered wider toward the top thereof located at the
downstream side of the drainage channel, whereby the flow passage
area is increased in the region where the flow speed of flushing
water is high so that a larger amount of flushing water flows
through the ascending channel. Consequently, since waste or the
like is conveyed with the flushing water with high flow speed to
the region where the ascending channel has the increased flow
passage area, the waste can successfully be conveyed along the
ascending channel.
[0014] Accordingly, the drainage channel according to the present
invention can perform desirable toilet flushing.
[0015] The bottom top may have a substantially horizontal surface
extending in a direction perpendicular to a drainage direction of
flushing water. In this case, a large amount of flushing water
flowing to the downstream end of the ascending channel can flow
downstream relative to the top at once. This can reliably form a
water screen in a water screen forming region by a constricted part
or the like, with the result that a siphon action can reliably be
caused in the drainage channel. Since the flushing water flows in
the drainage channel further swiftly as the result of occurrence of
siphon action, waste or the like can successfully be conveyed with
the flushing water with high flow speed to the region where the
ascending channel has the increased flow passage area, whereupon
the waste can successfully be conveyed along the ascending
channel.
[0016] The ascending channel may include an upstream end, a
vertical middle, a first region between the upstream end and the
vertical middle and a second region between the middle and an
upstream side of the bottom top, and the ascending channel has a
cross-sectional shape in a direction perpendicular to the drainage
direction of the flushing water. In the cross-sectional shape of
the ascending channel, the first region includes a first upper
region and first lower region both relative to the vertical middle,
and the first upper region has a larger flow passage area than the
first lower region. In the cross-sectional shape of the ascending
channel, the second region includes a second upper region and a
second lower region both relative to the vertical middle, and the
second lower region has a larger flow passage area than the second
upper region. In the cross-sectional shape, the ascending channel
includes a first upper region and a first lower region both
relative to a vertical middle of the first region, the first upper
region having a larger flow passage area than the first lower
region. In this case, the flow passage area in the upper side where
the flushing water has a higher flow speed is increased in the
region from the upper end of the ascending channel to the middle
part, whereas the flow passage area in the lower side where the
flushing water has a higher flow speed is increased in the region
from the middle part of the ascending channel to near the upstream
side of the top. This can reduce stagnation of flushing water in
the ascending channel, so that a large amount of flushing water can
successfully flow through an entire region of the ascending
channel. Consequently, waste or the like can successively be
conveyed in the ascending channel.
[0017] The channel bottom of the ascending channel may have a
substantially flat surface extending in a/the drainage direction of
the flushing water and in a direction perpendicular to the drainage
direction. In this case, since the flow passage area near the
bottom of the ascending channel can be increased, a larger amount
of flushing water can flow in the region where the flow speed of
the flushing water is high. Furthermore, the channel bottom of the
ascending channel is formed so as to be continuous to the bottom
top that extends perpendicular to the drainage direction of the
flushing water and has the substantially horizontal surface.
Accordingly, the flushing water can flow smoothly in the ascending
channel. Consequently, the waste or the like in the ascending
channel can successfully be conveyed.
[0018] The ascending channel may have a vertical maximum length
that is enlarged from the upstream end toward the downstream side
in a/the cross-sectional shape of the ascending channel in the
direction perpendicular to the drainage direction of the flushing
water. In this case, the vertical length in the cross-sectional
shape can be increased at the downstream side of the ascending
channel. This can prevent the waste or like from being caught on
the upper surface of the ascending channel when the waste or the
like passes through the bottom top of the downstream end of the
ascending channel. Consequently, the waste or the like can be
prevented from remaining in the drainage channel to thereby be
conveyed successfully.
[0019] The drainage channel may further comprise a descending
channel communicating with a downstream side of the ascending
channel and descending toward the downstream side of the drainage
channel, the descending channel having a ledge extending from the
bottom top of the ascending channel to inwardly protrude along an
inner periphery of the descending channel. In this case, since the
ledge is formed so as to protrude inward along the inner periphery
of the descending channel, the flushing water having flowed over
the bottom top of the ascending channel further flows along the
ledge, whereby the flushing water can be supplied into the rear of
descending channel. The flushing water having flowed downward from
the ledge collides against a constricted part formed lower than the
ledge to splash around, thereby forming a water screen in the water
screen forming region. Consequently, a siphon action can early be
caused in the drainage channel. More specifically, the siphon
action can early be caused even by the use of a smaller amount of
flushing water.
[0020] The invention also provides a drainage channel of a flush
toilet, comprising an ascending channel which communicates with a
downstream side of a toilet bowl and ascends toward a downstream
side of the drainage channel, wherein the ascending channel has a
cross-sectional shape in a direction perpendicular to the drainage
direction of the flushing water. In the cross-sectional shape, the
ascending has a vertical maximum length that is increased from the
upstream end toward the downstream side, and the upstream end has
an inner surface having a larger crosswise dimension than a
longitudinal dimension.
[0021] In this drainage channel, part of the flushing water flowing
at the lower side of the ascending channel at a lower flow speed is
reduced by reducing the longitudinal dimension of the inner surface
of the upstream end of the ascending channel. An amount of flushing
water flowing at the upper side at a higher speed is increased by
increasing the crosswise dimension of the upstream end of the
ascending channel. This can increase the flow speed of the flushing
water flowing through the upstream end of the ascending channel,
whereupon waste or the like can be caused to successfully flow into
the drainage channel and can smoothly be discharged. Furthermore,
waste or the like can be prevented from clogging the ascending
channel since the vertical maximum length of the ascending channel
is increased from the upstream end toward the downstream side.
[0022] Accordingly, the drainage channel according to the present
invention can perform desirable toilet flushing.
[0023] The ascending channel may have an upper surface formed into
an angled shape such that the upper surface is gradually enlarged
from a middle part thereof toward right and left lower parts
thereof, in a/the cross-sectional shape of the ascending channel in
the direction perpendicular to the drainage direction of the
flushing water. In this case, when the region where the flow speed
of the flushing water is decreased near the upper surface of the
ascending channel is formed into the angled shape, the flow passage
area of the region is rendered smaller such that the flow speed of
the flushing water is increased, whereupon the flushing water can
be prevented from stagnation. Consequently, the flushing water can
be caused to successfully flow through the ascending channel and
accordingly, waste or the like can be conveyed successfully.
[0024] The channel bottom of the ascending channel may have rising
surfaces rising from right and left ends thereof, and the rising
surfaces have maximum heights near an upstream side of the bottom
top located at the downstream side of the drainage channel,
respectively, in the cross-sectional shape perpendicular to the
drainage direction of the flushing water. In this case, since the
heights of the rising surfaces become a maximum near the upstream
side of the bottom top of the ascending channel, the flow passage
area of this part is increased with the result that the flow of
flushing water is rendered smoother. Consequently, the vicinity of
the upstream side of the bottom top of the ascending channel can be
prevented from being clogged with the waste or the like.
[0025] The upper surface of the ascending channel may be formed
into an inclined surface extending from a middle part thereof
rightward downward and leftward downward and inwardly swollen, in
the cross-sectional shape perpendicular to the drainage direction
of the flushing water. In this case, the flushing water tends to
stagnate in a region near the upper surface. When the region is
composed of an inclined surface that is inwardly swollen, the flow
speed of the flushing water flowing in the region is increased such
that the flushing water can be prevented from stagnation.
Consequently, the flushing water can flow through the ascending
channel successfully and the waste or the like can desirably be
conveyed through the ascending channel.
[0026] The ascending channel may have corners between the channel
bottom and the rising surfaces rising from the right and left ends
of the channel bottom near the upstream end of the ascending
channel respectively. The corners may be formed into respective
rounded surfaces. The rounded surface of one of the right and left
corners may have a larger curvature than the rounded surface of the
other corner. A spiral flow resulting from one formed in the toilet
bowl flows in the ascending channel in the vicinity of the upstream
end thereof. In this case, the flushing water smoothly flows in
along the corner with the rounded surface having a smaller
curvature. On the other hand, the spiral flow collides against the
rising surfaces connected by the corner with the rounded surface
having a larger curvature, whereby the flushing water flows
downstream of the ascending channel. Thus, the flow of flushing
water can be changed to the drainage direction at the upstream end
of the ascending channel, whereupon the flow of flushing water can
be rendered smoother. Consequently, the drainage channel of the
flush toilet can successfully convey the waste or the like.
[0027] The drainage channel may further comprise a pipe-like
introduction passage downwardly inclined from a lower end of the
toilet bowl toward the upstream end of the ascending channel. In
this case, the introduction passage rectifies the flushing water
inflowing with spiral movement along the toilet bowl surface into a
flow along the ascending channel. Consequently, the flushing water
can smoothly flow through the ascending channel and the waste or
the like can successfully be conveyed.
[0028] The invention further provides a drainage channel of a flush
toilet, comprising a descending channel which communicates with a
downstream side of an ascending channel communicating with a
downstream side of a toilet bowl and ascending toward a downstream
side of the drainage channel, the descending channel descending
toward the downstream side, wherein the descending channel has a
ledge which is formed so as to inwardly protrude along an inner
periphery of the descending channel.
[0029] Since the ledge is formed along the inner periphery of the
descending channel so as to inwardly protrude, the flushing water
flows along the ledge to thereby be transferred to rearward of the
descending channel. The flushing water having flowed downward from
the ledge collides against a constricted part formed downward
relative to the ledge to thereby splash, forming a water screen in
a water screen forming region. Consequently, a siphon action can
early be caused in the drainage channel. More specifically, the
siphon action can be caused early even when an amount of flushing
water is smaller, and waste or the like can be conveyed
successfully.
[0030] Accordingly, the drainage channel according to the present
invention can perform desirable toilet flushing.
[0031] The ledge may descend rearward along the inner periphery of
the descending channel. In this case, the flushing water can flow
as far as to the rear of the descending channel along the inner
periphery of the descending channel even when an amount of flushing
water flowing along the ledge is small. Consequently, the flushing
water flowing downward from the inner periphery of the descending
channel can reliably form a water screen even when its amount is
smaller. More specifically, the siphon action can be caused early
even when an amount of flushing water is smaller, and waste or the
like can be conveyed successfully.
[0032] The ledge may be formed into an inclined surface directed
inwardly upward. In this case, although the provision of the ledge
reduces the flow passage area of the descending channel, the change
in the reduction of the flow passage area can be slowed down. This
can prevent the clogging with the waste or the like due to the
ledge and realize successful execution of conveyance of waste or
the like.
[0033] The descending channel may have a rear surface and the ledge
may extend near a middle part of the rear surface of the descending
channel. In this case, the flushing water can reliably be sent
along the inner periphery of the descending channel to the middle
rear surface of the descending channel. Consequently, the flushing
water flowing downward from the inner periphery of the descending
channel can reliably form a water screen even when its amount is
smaller. In particular, when the drainage channel has a lateral
channel which communicates with a downstream end of the descending
channel and extends laterally, a water screen is formed so as to
spread from a lower end of the rear surface of the descending
channel, whereupon a siphon action is caused in the drainage
channel. Consequently, the water screen can reliably be formed and
the siphon action can be caused in the drainage channel by sending
the flushing water to the middle rear surface of the descending
channel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 is a cross-sectional view of the flush toilet of
embodiment 1;
[0035] FIG. 2 is a plan view of the flush toilet;
[0036] FIG. 3 is a cross-sectional view taken along line A-A in
FIG. 1;
[0037] FIG. 4 is a cross-sectional view taken along line B-B in
FIG. 1;
[0038] FIG. 5 is a cross-sectional view taken along line C-C in
FIG. 1;
[0039] FIGS. 6A, 6B and 6C are a cross-sectional view of an
ascending channel in embodiment 1, sectional views taken along
lines D-D to H-H in FIG. 6A and a cross-sectional view taken along
line I-I in FIG. 6A, respectively;
[0040] FIG. 7 is a cross-sectional view taken along line J-J in
FIG. 1;
[0041] FIG. 8 is a cross-sectional view taken along line K-K in
FIG. 1;
[0042] FIG. 9 is a cross-sectional view taken along line L-L in
FIG. 1;
[0043] FIG. 10 is a cross-sectional view taken along line P-P in
FIG. 1;
[0044] FIG. 11 is a cross-sectional view taken along line Q-Q in
FIG. 1;
[0045] FIG. 12 is a cross-sectional view taken along line R-R in
FIG. 1;
[0046] FIG. 13 is a cross-sectional view taken from opposite line
R-R in FIG. 1;
[0047] FIG. 14 is a cross-sectional view of the flush toilet of
embodiment 2;
[0048] FIG. 15 is a cross-sectional view taken along line W-W in
FIG. 14;
[0049] FIG. 16 is a cross-sectional view taken along line X-X in
FIG. 14;
[0050] FIG. 17 is a cross-sectional view taken along line Y-Y in
FIG. 14;
[0051] FIG. 18 is a cross-sectional view taken along line Z-Z in
FIG. 14;
[0052] FIG. 19 is a partial sectional view of the descending
channel in another embodiment;
[0053] FIG. 20 is a partial sectional view of the descending
channel in further another embodiment;
[0054] FIG. 21 is a cross-sectional view of the flush toilet of
embodiment 3;
[0055] FIG. 22 is a plan view of the flush toilet of embodiment
3;
[0056] FIG. 23 is a cross-sectional view taken along line A-A in
FIG. 21;
[0057] FIG. 24 is a cross-sectional view taken along line B-B in
FIG. 21;
[0058] FIG. 25 is a cross-sectional view taken along line C-C in
FIG. 21;
[0059] FIG. 26 is a cross-sectional view taken along line D-D in
FIG. 21;
[0060] FIG. 27 is a cross-sectional view taken along line E-E in
FIG. 21;
[0061] FIG. 28 is an enlarged sectional view taken along line F-F
in FIG. 21;
[0062] FIG. 29 is an enlarged sectional view taken along line G-G
in FIG. 21;
[0063] FIG. 30 is an enlarged sectional view taken along line I-I
in FIG. 21;
[0064] FIG., 31 is an enlarged sectional view taken along line J-J
in FIG. 21;
[0065] FIG. 32 is an enlarged sectional view taken along line K-K
in FIG. 21;
[0066] FIG. 33 is an enlarged sectional view of an ascending
channel of the flush toilet of embodiment 4;
[0067] FIG. 34 is a cross-sectional view taken along line L-L in
FIG. 33;
[0068] FIG. 35 is a cross-sectional view taken along line M-M in
FIG. 33;
[0069] FIG. 36 is a cross-sectional view taken along line N-N in
FIG. 33;
[0070] FIG. 37 is a cross-sectional view taken along line O-O in
FIG. 33; and
[0071] FIG. 38 is a cross-sectional view taken along line P-P in
FIG. 33.
MODE FOR CARRYING OUT THE INVENTION
[0072] Embodiments 1 to 4 which embody flush toilets provided with
the drainage channel of flush toilet will be described with
reference to the accompanying drawings.
Embodiment 1
[0073] The flush toilet of embodiment 1 includes a toilet body 1, a
tank body 2 set on a rear top of the toilet body 1, a distribution
conduit 3 through which flushing water stored in the tank body 2 is
discharged into the toilet body 1 and connecting piping 4
communicating between a drain outlet 40A of the toilet body 1 and
an inlet of a drainage conduit (not shown) which is open in a floor
of a toilet room in which the toilet body 1 is installed. The
connecting piping 4 forms a constricted part 5 against which
flushing water having flowed downward from the drain outlet 40A
collides to thereby splash. A water screen is formed in a water
screen forming region S when the flushing water collides against
the constricted part 5 to thereby splash. Consequently, a siphon
action can be caused in the drainage channel.
[0074] The toilet body 1 includes a toilet bowl 10, an introduction
passage 20, an ascending channel 30 and a descending channel 40. A
drainage channel of the flush toilet is constituted by the
introduction passage 20, the ascending channel 30, the descending
channel 40 and the connecting piping 4.
[0075] The toilet bowl 10 has an upper inner peripheral edge
forming a rim water passage 11. The distribution conduit 3 has an
inlet 3A connected to a drain outlet of the tank body 2 and first
and second discharge conduits 3B and 3C both of which are
distributed from each other below the inlet 3A. Upon execution of
toilet flushing, flushing water stored in the tank body 2 is
discharged from the first discharge conduit 3B toward the rim water
passage 11, and the flushing water is also discharged from the
second discharge conduit 3C toward the rear of the toilet bowl 10.
The flushing water discharged from the first discharge conduit 3B
along the rim water passage 11 flows from the rim water passage 11
downward onto the inner surface of the toilet bowl 10. Furthermore,
since an amount of flushing water discharged from the first conduit
3B is larger than from the second conduit 3C, a counter-clockwise
swirl flow FL is formed in the toilet bowl 10 as viewed above the
toilet bowl 10.
[0076] The introduction passage 20 is continuous to a lower end of
the toilet bowl 10 and is formed into the shape of a pipe as shown
in FIGS. 1 and 3 to 5. The introduction passage 20 is inclined
downward from the lower end of the toilet bowl 10 toward the rear
of the toilet body 1. More specifically, the introduction passage
20 is downwardly inclined toward the upstream end 31 of the
ascending channel 30. The introduction passage 20 has a downstream
end that is formed successively to the upstream end 31 of the
ascending channel 30. The introduction passage 20 has a
cross-sectional shape perpendicular to the drainage direction of
the flushing water. In the cross-sectional shape, left lower
corners 20L and 31L are formed into rounded surfaces having smaller
curvatures and curved more gently than right lower corners 20R and
31R respectively. A right side surface 31C rises linearly.
[0077] Flushing water is formed into the counter-clockwise swirl
flow FL in the toilet bowl 10, flowing into the introduction
passage 20. In this case, the flushing water smoothly flows into
the introduction passage 20 since the left lower corners 20L and
31L is the rounded surface having the gentle curve. The flushing
water having flowed into the introduction passage 20 further flows
through the right lower corners 20R and 31R having the larger
curvature and a tight curve, colliding against the linearly rising
right side surface 31C to thereby change the flow direction to the
downstream of the drainage channel. Thus, the flow of flushing
water swirling in the toilet bowl 10 can be changed to the flow
toward the downstream of the drainage channel by the introduction
passage 20, and the flow of flushing water toward the downstream is
accelerated to thereby be rectified.
[0078] The upstream end 31 of the ascending channel 30 which is the
downstream end of the introduction passage 20 has a horizontally
long substantially rectangular cross-sectional shape as shown in
FIG. 5. The flushing water with a higher flow speed flows at the
upper surface 31T side due to the change in the drainage direction
of the flushing water from the downward direction to the upward
direction at the upstream end 31 of the ascending channel 30. When
the vertical dimension is increased in a cross-sectional shape of a
part of the drainage channel near the upstream end 31 of the
ascending channel 30, the flow speed of the flushing water at the
channel bottom 31B side is reduced, whereupon there is a
possibility that the flushing water rectified near the channel
bottom 31B side may stagnate. In view of the problem, the vertical
dimension of the ascending channel 30 is rendered smaller near the
upstream end 31 of the ascending channel 30 so that the rectified
flushing water can be prevented from stagnating, and a lateral
dimension of the ascending channel 30 is increased so that a
predetermined flow rate is ensured. As a result, the upstream end
31 of the ascending channel 30 is formed so as to have a
horizontally substantially rectangular cross-sectional shape.
[0079] The ascending channel 30 is also formed so that a flow
passage area A1 of a region above the vertical middle M is larger
than a flow passage area B1 of a region below the vertical middle M
at the upstream end 31 of the ascending channel 30. Consequently,
the upper side flow passage area A1 in the region where the flow
speed of the flushing water is higher is increased, so that a
larger amount of flushing water can flow into the ascending channel
30. Furthermore, the flow speed of the flushing water is increased
near the channel bottom 31B in the upstream end 31 of the ascending
channel 30, so that the stagnation of the rectified flushing water
can be reduced. Additionally, as described above, the flow of
flushing water in the introduction passage 20 is changed to the
downstream direction of the drainage channel by the right side
surface 31C rising linearly from the right lower corners 20R and
31R with tight curved surfaces having large curvatures
respectively, and the flow of flushing water in the downstream
direction is accelerated, whereby the flow of flushing water can be
optimized.
[0080] The ascending channel 30 rises from the upstream end 31
toward the rear of the toilet body 1 (the downstream side). The
ascending channel 30 is defined by being surrounded by a channel
bottom 33, right and left side surfaces 34R and 34L rising from
right and left ends of the channel bottom 33 and an upper surface
35 connecting between upper ends of the right and left side
surfaces 34R and 34L, as shown in FIGS. 1, 6A to 6C and 7.
[0081] The ascending channel 30 has a cross-sectional shape
perpendicular to a drainage direction of flushing water, in which
cross-sectional shape a maximum vertical length is enlarged from
the upstream end 31 toward the downstream side (from the upstream
end 31 to the section taken along line D-D in FIG. 6A).
Consequently, the vertical length in the cross-sectional shape can
be increased at the downstream side of the ascending channel 30.
This can prevent waste or the like from being caught on the upper
surface 35 of the ascending channel 30 when the waste or the like
passes by a bottom top 32 of the downstream end of the ascending
channel 30. Accordingly, the waste or the like can successfully be
conveyed without remaining in the drainage channel.
[0082] The ascending channel 30 is formed so that the channel
bottom 33 thereof is gradually widened toward the bottom top 32
located downstream of the channel bottom 33. The channel bottom 33
is formed into a flat surface extending in the drainage direction
of the flushing water and in a direction perpendicular to the
drainage direction. The bottom top 32 of the channel bottom 33 has
a substantially horizontal surface extending perpendicularly to the
drainage direction of the flushing water.
[0083] The flushing water near the channel bottom 33 of the
ascending channel 30 has a higher flow speed at the downstream side
than at the upstream side. Accordingly, a flow passage area of the
region where the flow speed of the flushing water is higher is
increased by gradually widening the channel bottom 33 of the
ascending channel 30 toward the bottom top 32 located downstream of
the channel bottom 33, so that a larger amount of flushing water
flows through the ascending channel 30. Furthermore, since the
channel bottom 33 is formed so as to be continuous to the bottom
top 32, the flushing water can smoothly flow in the ascending
channel 30. Consequently, the waste or the like can successfully be
conveyed through the ascending channel 30.
[0084] Furthermore, since the bottom top 32 has the substantially
horizontal surface extending perpendicularly to the drainage
direction of flushing water, a large amount of flushing water
flowing into the downstream end of the ascending channel 30 can
flow into the descending channel 40 at the downstream side of the
bottom top 32 at once. The flushing water having flowed through the
descending channel 40 collides against the constricted part 5 of
the connecting piping 4 to splash, thereby forming a water screen
in the water screen forming region S with the result that a siphon
action can reliably be caused in the drainage channel. Since the
occurrence of siphon action results in further vigorous flow of
flushing water through the drainage channel, the waste or the like
is conveyed together with the vigorous flushing water into the
region of the ascending channel 30 where the flow passage area is
increased. Consequently, the waste or the like can successfully be
conveyed through the ascending channel 30.
[0085] Accordingly, the drainage channel of the flush toilet
according to embodiment 1 can desirably perform toilet
flushing.
[0086] The upper surface 31T at the upstream end 31 is formed into
an upwardly swollen curved surface in the cross-sectional shape of
the ascending channel 30 perpendicular to the drainage direction of
flushing water. A part of the upper surface 35 located at the
downstream side of the upstream end 31 is formed into an angled
shape such that the upper surface 35 is gradually enlarged from a
middle part thereof toward rightward downward and leftward
downward. Consequently, since the flow passage area is rendered
smaller in a region where the flow speed of the flushing water is
decreased near the upper surface 35 of the ascending channel 30,
the flow speed of the flushing water is increased such that the
rectified flushing water can be prevented from stagnation.
Consequently, the flushing water in the ascending channel 30 can
flow successfully and the waste or the like can be conveyed
successfully.
[0087] Furthermore, the upper surface 35 is formed into an inclined
surface extending from a middle part thereof rightward downward and
leftward downward and inwardly swollen, at the upstream end 31 side
of the upper surface 35 formed into the angled shape. The flushing
water tends to stagnate in a region near the upper surface 35 since
the flushing water flows near the downstream side of the upstream
end 31 immediately after the direction of flushing water has been
changed from the downward direction to the upward direction.
Accordingly, when the part of the upper surface 35 where the
flushing water tends to stagnate is formed into the inclined
surface swollen inward, the flow speed of the flushing water can be
further increased and the rectified flushing water can be prevented
from stagnating. Consequently, the flushing water can flow in the
ascending channel 30 successfully and the waste or the like can be
conveyed in the ascending channel successfully.
[0088] At the upstream end 31, the ascending channel 30 has an
upper region and a lower region relative to the vertical middle M
in the cross-sectional shape thereof in the direction perpendicular
to the drainage direction of the flushing water. The upper region
has a flow passage area A1 and the lower region has a flow passage
area B1. The ascending channel 30 is formed so that the flow
passage area A1 of the upper region is larger than the flow passage
area B1 of the lower region. More specifically, since the flow
speed of the flushing water is higher near the upper surface 31T
side at the upstream end 31 of the ascending channel 30, the flow
passage area A1 at the upper region is rendered larger so that a
larger amount of flushing water flows through the upper region. The
flow speed of the flushing water near the upper surface 35 becomes
lower as the flushing water flows downstream from the upstream end
31. Accordingly, in the cross-sectional shape of the ascending
channel 30 in the direction perpendicular to the drainage direction
of the flushing water, the flow passage area of the upper region
relative to the vertical middle M is gradually rendered small,
whereas the flow passage area of the lower region relative to the
vertical middle M is accordingly rendered large. The ascending
channel 30 is formed so that the upper region has a larger flow
passage area than the lower region in a region between the upstream
end 31 and an intermediate part 30M. In a region between the
intermediate part 30M and the downstream end, the ascending channel
30 is formed so that a flow passage area B2 of a lower region
relative to the vertical middle M is larger than a flow passage
area A2 of an upper region in the cross-sectional shape of the
ascending channel 30 in the direction perpendicular to the drainage
direction of the flushing water, as shown in FIGS. 6B and 7.
[0089] Thus, the flow passage area at the upper region where the
flow speed of the flushing water is higher is rendered larger in
the region between the upstream end 31 of the ascending channel 30
and the intermediate part 30M, and the flow passage area at the
lower region where the flow speed of the flushing water is higher
is rendered larger in the region between the intermediate part 30M
and the downstream end. This can reduce stagnation of the rectified
flushing water in the ascending channel 30 and realize successful
flow of a large amount of flushing water in the entire region of
the ascending channel 30. Consequently, the waste or the like can
successfully be conveyed through the ascending channel 30.
[0090] The descending channel 40 is formed continuously to the
downstream side of the ascending channel 30 as shown in FIGS. 1 and
8 to 13. The descending channel 40 extends vertically downward,
that is, descends toward the downstream side. The descending
channel 40 has a lower end formed with a drain outlet 40A. The
connecting piping 4 is connected to the lower end of the descending
channel 40. The drain outlet 40A is inserted into a connecting port
at the upstream side of the connecting piping 4 to thereby be
capable of communicating via the connecting piping 4 with an inlet
of a drain pipe which is open in the floor face of a toilet
room.
[0091] The descending channel 40 has a ledge 41 comprising an
inclined surface which is formed so as to extend from the bottom
top 32 of the ascending channel 30 and protrude inward along an
inner periphery of the descending channel 40 and so as to be
directed inwardly upward. Since the ledge 41 protrudes inward along
the inner periphery of the descending channel 40, the flushing
water having flowed over the bottom top 32 flows along the ledge 41
to thereby be delivered to the rear of the descending channel 40.
The flushing water having flowed from the ledge 41 down into the
descending channel 40 collides against the constricted part 5
formed on the connecting piping 4, splashing. As a result, a water
screen is formed in a water screen forming region S such that a
siphon action can early be caused in the drainage channel. In other
words, even a small amount of flushing water can cause the siphon
action at an early stage of toilet flushing, and the waste or the
like can successfully be conveyed with the flush water.
[0092] Accordingly, the drainage channel of the flush toilet
according to embodiment 1 can perform desirable toilet
flushing.
[0093] Furthermore, the provision of the ledge 41 reduces the flow
passage area of the descending channel 40. However, since the ledge
41 comprises the inclined surface directed inwardly upward, the
change in the flow passage area can be rendered gradual.
Accordingly, the drainage channel can be prevented from being
clogged with waste or the like caught by the ledge 41, whereupon
the waste or the like can successfully be conveyed.
[0094] The ledge 41 descends rearward from the bottom top 32 of the
ascending channel 30 along the inner periphery of the descending
channel 40. Accordingly, the flushing water can be delivered along
the inner periphery of the descending channel 40 to the rear of the
descending channel 40 even when an amount of flushing water flowing
from the bottom top 32 to the ledge 41 is smaller. In other words,
even when an amount of flushing water is smaller, the flushing
Water flows downward from the periphery of the descending channel
40, whereupon a water screen can reliably be formed in the water
screen forming region S. Consequently, even a smaller amount of
flushing water can cause the siphon action early, so that the waste
or the like can successfully be conveyed with the flush water.
[0095] The width of the ledge 41 is gradually reduced toward the
rear along the inner periphery of the descending channel 40. The
ledge 41 acts as a resistance when the siphon action is caused and
the waste or the like flows through the descending channel with the
flushing water. Accordingly, when the width of the ledge 41 is
gradually reduced toward the rear, the siphon action can be caused
early and the resistance against the flushing water and the like
can be reduced, whereupon the waste or the like can successfully be
conveyed.
Embodiment 2
[0096] A flush toilet of embodiment 2 has a lateral channel 146
which communicates with a downstream end of the descending channel
140 of the toilet drainage channel and extends laterally toward the
rear of the toilet body 101, as shown in FIG. 14. The flush toilet
also has a reinforcement wall 150. The descending. channel 140
includes a rear surface 144, and the reinforcement wall 150 extends
vertically on a middle part of an outer periphery of the rear
surface 144 to thereby reinforce the rear of the toilet body 101.
The other construction of the flush toilet of embodiment 2 is
substantially the same as that of the flush toilet of embodiment 1.
Identical or similar parts in embodiment 2 is labeled by the same
reference symbols as those in embodiment 1 and the detailed
description of these parts will be eliminated.
[0097] The lateral channel 146 is formed in continuity with the
downstream end of the descending channel 140. The lateral channel
146 has a downstream end formed with the drain outlet 140A that is
open to the rear of toilet body 101. The drain outlet 140A is
inserted into an upstream side connection of the connecting member
5 to thereby be capable of communicating with the inlet of the
drain pipe which is drawn via the connecting member 5 from the wall
of the toilet room.
[0098] The descending channel 140 is defined by being surrounded by
a front surface 142 extending downward from the bottom top 32 of
the ascending channel 30, right and left side surfaces 143R and
143L extending rearward from right and left ends of the front
surface 142, a rear surface 144 connecting between rear ends of the
right and left side surfaces 143R and 143L, as shown in FIG. 15.
The descending channel 140 is formed integrally with the toilet
bowl 10, the introduction passage 20, the ascending channel 30 and
the like, constituting the toilet body 101. The toilet body 101 is
made from ceramic and manufactured by a slip casting method.
Accordingly, a recess 144A is formed in the inner periphery of a
part etc. on which the reinforcement wall 150 extends from the
outer periphery of the rear surface 144. The recess 144A results
from the dying of slurry causing shrinkage of the toilet body 101
in the manufacturing process.
[0099] The descending channel 140 has the ledge 141 comprising an
inclined surface which is formed so as to extend from the bottom
top 32 of the ascending channel 30 and protrude inward along an
inner periphery of the descending channel 140 and so as to be
directed inwardly upward, as shown in FIGS. 14 to 18. Since the
ledge 141 protrudes inward along the inner periphery of the
descending channel 140, the flushing water having flowed over the
bottom top 32 flows along the ledge 141 to thereby be delivered to
the rear of the descending channel 140. The flushing water having
flowed from the ledge 141 down into the descending channel 140
forms a water screen in the water screen forming region S that is a
boundary between the descending channel 140 and the lateral channel
146. As a result, a siphon action can early be caused in the
drainage channel. In other words, even a small amount of flushing
water can cause the siphon action early, and the waste or the like
can successfully be conveyed with the flush water.
[0100] Accordingly, the drainage channel of the flush toilet
according to embodiment 2 can also perform desirable toilet
flushing.
[0101] Furthermore, the provision of the ledge 141 reduces the flow
passage area of the descending channel 140. However, since the
ledge 141 comprises the inclined surface directed inwardly upward,
the change in the flow passage area can be rendered gradual.
Accordingly, the drainage channel can be prevented from being
clogged with waste or the like caught by the ledge 141, whereupon
the waste or the like can successfully be conveyed.
[0102] The ledge 141 descends rearward from the bottom top 32 of
the ascending channel 30 along the inner periphery of the
descending channel 140. Accordingly, the flushing water can be
delivered along the inner periphery of the descending channel 140
to the rear of the descending channel 140 even when an amount of
flushing water flowing from the bottom top 32 to the ledge 141 is
smaller. In other words, even when an amount of flushing water is
smaller, the flushing water flows downward from the periphery of
the descending channel 140, whereupon a water screen can reliably
be formed in the water screen forming region S. Consequently, even
a smaller amount of flushing water can cause the siphon action
early, so that the waste or the like can successfully be conveyed
with the flush water.
[0103] The width of the ledge 141 is gradually reduced toward the
rear along the inner periphery of the descending channel 140. The
ledge 141 acts as a resistance when the siphon action is caused and
the waste or the like flows through the descending channel 140 with
the flushing water. Accordingly, when the width of the ledge 141 is
gradually reduced toward the rear, the siphon action can be caused
early and the resistance against the flushing water and the like
can be reduced, whereupon the waste or the like can successfully be
conveyed.
[0104] Additionally, the ledge 141 extends to the middle part of
the rear surface 144 of the descending channel 140, with the result
that the flushing water can reliably be delivered along the inner
periphery of the descending channel 140 to the middle part of the
rear surface 144. As a result, the water screen is formed so as to
be spread from the lower end of the rear surface 144, whereby the
siphon action can be caused in the drainage channel. In particular,
the flushing water can be delivered to the recess 144A formed in
the middle of the rear surface 144. This can reliably prevent the
failure that no water screen is formed around the recess 144A such
that no siphon action is caused in the drainage channel.
Consequently, the siphon action can reliably be caused in the
drainage channel, so that the waste or the like can successfully be
conveyed with the flush water.
Embodiment 3
[0105] The flush toilet of embodiment 3, as shown in FIGS. 21 and
22, includes a toilet body 51, a tank body 52 set on a rear top of
the toilet body 51, a distribution conduit 53 through which
flushing water stored in the tank body 52 is discharged into the
toilet body 51 and connecting piping 54 communicating between a
drain outlet 90A of the toilet body 51 and an inlet of a drainage
conduit (not shown) which is open in a floor of a toilet room in
which the toilet body 51 is installed. The toilet body 51 includes
a toilet bowl 60, an introduction passage 70, an ascending channel
80 and a descending channel 90. A drainage channel of the flush
toilet is constituted by the introduction passage 70, the ascending
channel 80, the descending channel 90 and the connecting piping
54.
[0106] The connecting piping 54 includes a first constricted part
55A formed beneath the drain outlet 90A and a second constricted
part 55B formed in a lower portion thereof. The flushing water
collides against the first and second constricted parts 55A and 55B
to thereby splash, forming a water screen near the constricted
parts 55A and 55B. Consequently, a siphon action can be caused in
the drainage channel.
[0107] The toilet bowl 60 has a first bowl surface 61, a second
bowl surface 62 having a, larger inclination than the first bowl
surface and extending downward in continuity with the first bowl
surface 61, and a third bowl surface 63 extending above a rear part
of the second bowl surface 62 and curved upward.
[0108] The toilet bowl 60 has an upper inner peripheral edge
forming a rim water passage 64. The distribution conduit 53 has an
inlet 53A connected to a drain outlet of the tank body 52 and first
and second discharge conduits 53B and 53C both of which are
distributed from each other below the inlet 53A. Upon execution of
toilet flushing, flushing water stored in the tank body 52 is
discharged from the first discharge conduit 53B toward the rim
water passage 64, and the flushing water is also discharged from
the second discharge conduit 53C toward the rear of the toilet bowl
60.
[0109] The flushing water discharged from the first discharge
conduit 53B along the rim water passage 64 flows from the rim water
passage 64 downward onto the first and second bowl surfaces 61 and
62. Accordingly, a counter-clockwise horizontal swirl flow is
formed in the toilet bowl 60 as viewed above the toilet bowl
60.
[0110] Furthermore, the flushing water discharged from the second
discharge conduit 53C flows downward along the third bowl surface
63, flowing directly into the introduction passage 70. Accordingly,
the force of the horizontal swirl flow in the toilet bowl 60 can be
reduced at the rear of the toilet bowl 60 and can be changed into a
swirl flow on a plane substantially perpendicular to the drainage
direction of the introduction passage 70. Consequently, since waste
or the like can be collected to the middle of the introduction
passage 70 without being spread, the waste or the like can smoothly
be discharged.
[0111] The first bowl surface 61 is formed into a downwardly
recessed curved recess 61A in the front widthwise middle thereof on
a planar view, as shown in FIGS. 23 and 24. Furthermore, the recess
61A has both widthwise ends formed with upwardly protruding curved
convex portions 61B respectively on the planar view. The convex
portion 61B is formed into a curved surface having a smaller
curvature than the recess 61A.
[0112] The recess 61A gradually descends toward the rear side of
the toilet bowl 60 and can desirably prevent urine from splashing
on the first bowl surface 61. The flushing water having flowed
downward from the rim water passage 64 onto the first bowl surface
61 of the toilet bowl 60 further flows along the recess 61A to the
second bowl surface 62 side at an early stage of toilet
flushing.
[0113] The second bowl surface 62 is formed into a convex shape in
which the entire periphery thereof is downwardly vertical or
swollen to the sealing water surface W side, as shown in FIGS. 21
and 25 to 27. More specifically, the second bowl surface 62 rises
from the outer periphery of the sealing water surface W such that
the flushing water swirling on the first bowl surface 61 can early
flow downward along the second bowl surface 62 to thereby flow into
the introduction passage 70. Accordingly, the waste or the like can
be collected into the introduction passage 70 by the second bowl
surface 62 without being spread. The second bowl surface 62 has an
entire upper periphery formed into a curved portion R with a curved
convex shape. The third bowl surface 63 is formed into a part of
the curved portion R in the rear part of the toilet bowl 60.
[0114] The toilet bowl 60 has a rear in which the curved portion R
is formed into a curved surface with a smaller curvature.
Accordingly, the flushing water is easy to flow downward toward the
introduction passage 70. On the other hand, the toilet bowl 60 has
a front in which the curved portion R is formed into a curved
surface with a larger curvature. Accordingly, since the second bowl
surface 62 is formed into the vertical shape, the flushing water
flowing downward into the second bowl surface 62 to thereby swirl
can be prevented from re-spreading outward above the second bowl
surface 62, whereupon the flushing water can be directed to the
introduction passage 70 early.
[0115] The sealing water surface W has a substantially elliptic
shape long in the front-back direction as viewed in a planar view,
as shown in FIG. 22. The sealing water surface W includes a front
side W1 having a largest curvature as viewed in the planar view. As
a result, the flushing water is caused to flush back on the front
right and left side portions of the second bowl surface 62 to
thereby be directed to the introduction passage 70. Furthermore,
the sealing water surface W has a point P in front of the middle in
the front-back direction, and the width thereof is a maximum at the
point P as viewed in the planar view. The flushing water flowing
downward from the first bowl surface 61 along the second bowl
surface 62 onto the sealing water surface W is caused to splash on
the front side portion with a larger curvature, with the result
that the flow speed of the flushing water is increased in the rear
of the point P as the flushing water comes near the introduction
passage 70. Accordingly, since the waste or the like rapidly flows
into the introduction passage 70, the waste or like can be
collected into the upstream end 81 of the ascending channel 80 of
the drainage channel, and the siphon action can be caused
early.
[0116] The introduction passage 70 is continuous to the lower end
of the toilet bowl 60 and is formed into a tubular shape. The
introduction passage 70 is inclined downward from the lower end of
the toilet bowl 60 toward the rear of the toilet body 51. More
specifically, the introduction passage 70 is inclined downward
toward the upstream end 81 of the ascending channel 80. The
introduction passage 70 has a downstream end formed in continuity
with the upstream end 81 of the ascending channel 80. When flowing
along the inner periphery of the introduction passage 70, the
flushing water is constricted by the introduction passages 70 to
thereby be rectified, so that the flow of the flushing water is
rendered smooth.
[0117] The introduction passage 70 includes a channel bottom 70B
and corners 70E and 70D between the channel bottom 70B and right
and left sides 70C formed on the right and left sides of the
channel bottom 70B respectively, as shown in FIG. 27. The corners
70D and 70E are formed so as to have respective curved surfaces.
The left corner 70D has a smaller curvature than the right corner
70E, as viewed from the front of the toilet body 51. In other
words, the left corner 70D has a gentler curved surface than the
right corner 70E.
[0118] The flushing water formed into the counter-clockwise
horizontal swirl flow by the toilet bowl 60 is changed by the
flushing water flowing downward on the third bowl surface 63 into a
swirl flow swirling on a plane substantially perpendicular to the
drainage direction of the introduction passage thereby flowing into
the introduction passage 70. In this case, since the left corner
70D has a gentler curve, the flushing water smoothly flows into the
introduction passage 70. The flushing water having flowed into the
introduction passage 70 collides against the right side 70C rising
linearly from the right lower corner 70E with a tight curved
surface having a large curvature to thereby change the direction of
flow into the downstream direction of the introduction passage 70.
Consequently, the flushing water swirled by the toilet bowl 60 can
be changed by the introduction passage 70 into the flow directed to
the ascending channel 80 of the toilet drainage channel to thereby
be rectified.
[0119] The ascending channel 80 of the toilet drainage channel has
the upstream end 81 having an upper surface 81A and a channel
bottom 81B both formed into a substantially horizontal shapes
respectively, as shown in FIG. 28. The upper surface 81A has right
and left corners both of which are angular. The channel bottom 81B
has right and left corners 81E and 81D both of which are rounded,
and the upstream end 81 is formed into a generally cup-shape as a
whole. The left corner 81D has a smaller curvature than the right
corner 81E. More specifically, the left corner 81D has a gentler
curved surface than the right corner 81E.
[0120] The upstream end 81 of the ascending channel 80 has an
opening having a crosswise dimension larger than a lengthwise
dimension, and the lengthwise dimension X is 50 mm and the
crosswise dimension Y is 77 mm. Thus, the flushing water and
floating waste or the like can be rendered easier to flow into the
ascending channel 80 by setting the crosswise dimension larger than
the lengthwise dimension, whereupon the siphon action can be caused
early.
[0121] More specifically, the flow speed of the flushing water is
reduced at a lower part in the upstream end 81 of the ascending
channel 80 since the flushing water creeps into the lower side of
the upstream end 81, with the result of occurrence of stagnation.
Accordingly, when the lengthwise dimension of the upstream end 81
is reduced and the crosswise dimension thereof is increased, the
flow passage area of the upper part where the flushing water flows
faster is increased, whereupon the flushing water can smoothly flow
into the upstream end 81 of the ascending channel 80 and
accordingly be rectified. Furthermore, since the crosswise
dimension of the upstream end 81 of the ascending channel 80 is
larger, this part of the ascending channel 80 can be prevented from
being clogged with the waste or the like. Additionally, the flow
passage area of the upper part where the flow speed of the flushing
water is higher can be increased by rendering the right and left
corners of the upper surface angular.
[0122] The flushing water rectified in the introduction passage 70
is also rectified at the upstream end 81 of the ascending channel
80. Accordingly, the flushing water flows into the ascending
channel 80 in the rectified state. Consequently, the occurrence of
turbulent flow can be suppressed even when a lengthwise dimension
of the ascending channel 80 is increased, and the waste or the like
can be discharged smoothly.
[0123] The ascending channel 80 has the lengthwise dimension X of
62 mm and the crosswise dimension Y of 77 mm in a cross-sectional
shape in front of the bottom top 82 as shown in FIG. 32.
Furthermore, the ascending channel 80 includes the upper surface
middle part which forms an upwardly expanded space 80A. Since the
space 80A renders the waste easier to turn when the waste gets over
the bottom top 82, even hard and/or long waste can be discharged
over the bottom top 82 to the descending channel 90 side. In other
words, the drainage channel can be prevented from being clogged
with waste or the like near the bottom top 82. Consequently, when a
siphon action is caused in the drain channel, the waste or the like
can successfully be discharged with a smaller amount of flushing
water without the clogging of the drainage channel with the waste
or the like near the bottom top 82.
[0124] The ascending channel 80 has the bottom top 82 formed on the
substantially horizontal plane and extending in the direction
perpendicular to the drainage direction of the flushing water as
shown in FIG. 29. Accordingly, a large amount of flushing water
flows downward at a stroke into the descending channel 90 located
at the downstream side of the bottom top 82 when the sealing water
surface W in the ascending channel 80 is raised. Consequently, the
siphon action can be caused early and yet reliably. The bottom top
82 has a crosswise dimension Y that is 77 mm, which value is equal
to the crosswise dimension of the upstream end 81 of the ascending
channel 80.
[0125] The descending channel 90 is formed continuously to the
downstream side of the ascending channel 80 as shown in FIGS. 21,
30 and 31. The descending channel 90 is formed into a cylindrical
shape and extends vertically downward, that is, descends toward the
downstream side. The descending channel 90 has a lower end formed
with a drain outlet 90A. The drain outlet 90A side of the
descending channel 90 is inserted into an upstream side connecting
port of the connecting piping 54 to be connected to the connecting
piping 54 by the use of a packing P. The drain outlet 90A
communicates with an inlet of a drain pipe which is open in the
floor face of a toilet room via the connecting piping 54.
[0126] In this flush toilet, part of the flushing water swirls on
the toilet bowl 60 to flow downward along the second bowl surface
62, and other part of the flushing water flows downward along the
third bowl surface 63. The flushing water flowing through both
passages is collected into the introduction passage 70. The sealing
water surface W in the ascending channel 80 then rises and the
flushing water flows over the bottom top 82 downward into the
descending channel 90. The flushing water having been discharged
from the drain outlet 90A of the descending channel 90 collides
against the constricted portions 55A and 55B formed on the
connecting piping 54 to thereby splash. This forms a water screen
near the constricted portions 55A and 55B, with the result that the
siphon action can early be caused in the drainage channel. More
specifically, even a smaller amount of flushing water can early
cause the siphon action and accordingly, the waste or the like can
successfully be conveyed.
[0127] Accordingly, the drainage channel of the flush toilet
according to embodiment 3 can also perform desirable toilet
flushing.
Embodiment 4
[0128] The flush toilet of embodiment 4 differs from embodiment 3
in the configuration of the ascending channel 180 of the toilet
drainage channel as shown in FIGS. 33 to 38. Embodiment 4 is the
same as embodiment 3 in the other construction. Identical or
similar parts in embodiment 4 will be labeled by the same reference
symbols as those in embodiment 3 and detailed description of these
parts will be eliminated.
[0129] The ascending channel 180 has a cross-sectional shape in the
direction perpendicular to the drainage direction of the flushing
water. In the cross-section shape, the ascending channel 180
includes a channel bottom 183, rising surfaces 185 and 184 rising
longitudinally from right and left sides of the channel bottom 183
respectively, and angled upper surfaces 186, 187 and 188 connected
to upper ends of the rising surfaces 184 and 185.
[0130] The upper surface middle part 186 is located at a middle
part perpendicular to the. drainage direction of the flushing
water. The inclined surfaces 187 and 188 extending leftward and.
rightward from the upper surface middle part 186 so as to be
downwardly inclined and so as to extend toward upper ends of the
rising surfaces 184 and 185, respectively. The inclined surfaces
187 and 188 are formed, at an upstream side of the ascending
channel 180, into respective curved shapes swollen inward (to the
ascending channel 180 side) as shown in FIG. 34. The inclined
surfaces 187 and 188 is further formed, at the downstream side of
the ascending channel 180, into a substantially linear shape, as
shown in FIGS. 35 to 37.
[0131] Furthermore, the right and left rising surfaces 185 and 184
have respective maximum heights near the upstream side of the
bottom top 182 as shown in FIG. 38. The ascending channel 180 also
has a maximum flow passage area in this part thereof.
[0132] In the ascending channel 180, the flushing water flowing
from the upstream side to the downstream side forms a water flow WS
with higher flow speed as shown in FIG. 33. More specifically, the
upstream end 181 of the ascending channel 180 has a cross-sectional
shape in the direction perpendicular to the drainage direction of
the flushing water. The flushing water flows into the lower side at
the upstream end 181 in the cross-sectional shape of the ascending
channel 180, with the result that the flow speed of the flushing
water is reduced. Accordingly, the flushing water tends to easily
stagnate in the lower side in the cross-sectional shape of the
ascending channel 180 in the direction perpendicular to the
drainage direction of the flushing water. On the other hand, in the
upstream end 181 of the ascending channel 180, a water flow in the
upper side in the aforesaid cross-sectional shape flows in the
ascending channel 180, maintaining its higher flow speed. The water
flow with the higher flow speed flows in the ascending channel 180
toward the bottom top 182.
[0133] Accordingly, the flow speed at the channel bottom 183 side
is increased in a section from the middle part of the ascending
channel 180 to a part before the bottom top 182. As a result, the
flow speed is reduced at the side of the upper surfaces 186, 187
and 188, whereby the flushing water tends to easily stagnate. In
view of this, the upper surfaces 186 to 188 are formed into the
angled shape, and the inclined surfaces 187 and 188 are formed into
the curved shapes swollen inside, whereupon the flow speed at the
side of the upper surfaces 186 to 188 is maintained so as not to be
reduced and accordingly, the flushing water flows smoothly.
[0134] Thus, in the ascending channel 180, the flow passage area of
the part where the water flow WS with a higher flow speed flows is
increased, and the flow passage area of the other part is reduced,
whereby the flushing water can flow smoothly without stagnation.
More specifically, in the part of the ascending channel 180 from
the upstream end 181 to the middle part thereof, the upper side
water flow maintains the higher flow speed in the cross-sectional
shape of the ascending channel 180 in the direction perpendicular
to the drainage direction of the flushing water. Accordingly, the
flow passage area at the upper side relative to the middle in the
vertical direction is formed so as to be larger than the flow
passage area at the lower side. In the part of the ascending
channel 180 from the middle part to the vicinity of the upstream
side of the bottom top 182, the flow passage area at the lower side
relative to the middle in the vertical direction is formed so as to
be larger than the flow passage area at the upper side.
Furthermore, the channel bottom 183 of the ascending channel 180 is
formed into the flat surface extending in the drainage direction of
the flushing water and in the direction perpendicular to the
drainage direction of the flushing water. Consequently, a large
amount of flushing water with the higher flow speed can flow along
the channel bottom 183 from the middle part to the bottom top 182
of the ascending channel 180.
[0135] The ascending channel 180 is formed so that the heights of
the rising surfaces 184 and 185 becomes maximum in the vicinity of
the upstream side of the bottom top 182, whereby the flow passage
area is increased as shown in FIG. 38. Consequently, since waste or
the like tends to easily turn in passing over the bottom top 182 of
the ascending channel 180, the ascending channel 180 can be
prevented from being clogged with the waste or the like at the
bottom top 182. Furthermore, the ascending channel 180 is formed
with the angled upper surfaces 186 to 188 located near the upstream
side of the bottom top 182. This maintains the flow speed of the
flushing water at the side of the upper surfaces 186 to 188 so that
the flow speed is prevented from being excessively reduced.
Consequently, the ascending channel 180 can also be prevented from
being clogged with the waste or the like at the bottom top 182.
[0136] Accordingly, the drainage channel of the flush toilet
according to embodiment 4 can also perform desirable toilet
flushing.
[0137] The invention should not be limited to the embodiments 1 to
4 described above with reference to the drawings but, for example,
the following embodiments covers the technical scope of the
invention.
[0138] (1) Although the ascending channel is formed in continuity
with the downstream end of the introduction passage in each of
embodiments 1 to 4, the ascending channel may be formed independent
of the downstream end of the introduction passage and connected to
the downstream end.
[0139] (2) Although descending channel is formed in continuity with
the downstream side of the ascending channel in each of embodiments
1 to 4, the descending channel may be formed independent of the
ascending channel and connected to the downstream side of the
ascending channel.
[0140] (3) Although the flush toilet is configured so that flushing
water is stored in the tank body set on the rear upper surface of
the toilet body and supplied to the toilet body, in each of
embodiments 1 to 4, the flush toilet may not be provided with any
tank body and the flush water may directly be supplied via an
on-off valve from a water supply source.
[0141] (4) In the cross-sectional shape of the ascending channel in
the direction perpendicular to the drainage direction of flush
water, the relation between the flow passage area ratios of upper
and lower regions relative to the vertical middle of the ascending
channel are reversed at the middle of the ascending channel in each
of embodiments 1, 2 and 4. However, the ratio between the flow
passage areas of upper and lower regions may be constant throughout
the ascending channel.
[0142] (5) Although the channel bottom of the ascending channel is
formed into the substantially flat surface in each of embodiments
1, 2 and 4, the channel bottom may not be flat.
[0143] (6) Although the bottom top of the ascending channel has the
substantially horizontal surface extending perpendicularly to the
drainage direction of flushing water in each of embodiments 1 to 4,
the bottom top may not be substantially flat.
[0144] (7) Although the upper surface of the ascending channel is
formed into the angled shape in each of embodiments 1, 2 and 4, the
upper surface may not be angled.
[0145] (8) Although the ledge is inclined rearwardly downward along
the inner periphery of the descending channel in each of
embodiments 1 and 2, the ledge may not be inclined downward.
[0146] (9) Although the width of the ledge is gradually reduced
toward the rear along the inner periphery of the descending channel
in each of embodiments 1 and 2, the width of the ledge may not be
reduced.
[0147] (10) Although the ledge is formed into the inwardly upward
inclined surface in each of embodiments 1 and 2, the ledge may be a
horizontal surface 241 as shown in FIG. 19 or an outwardly upward
inclined surface 341 as shown in FIG. 20.
[0148] (11) Although the introduction passage connects between the
lower end of the toilet bowl and the upstream end of the ascending
channel in each of embodiments 1 to 4, the introduction passage may
not be provided and the upstream end of the ascending channel may
be connected directly to the lower end of the toilet bowl.
[0149] (12) Although the counterclockwise swirl flow is formed in
the toilet bowl in each of embodiments 1 to 4, the flushing water
may be swirled clockwise. In this case, the introduction passage
may be mirror-reversed in shape relative to the shape in each
embodiment.
[0150] (13) Although the connecting piping is formed with one or
two constricted portions in each of embodiments 1, 3 and 4, the
descending channel may be provided with one or two constricted
portions.
[0151] (14) In each of embodiments 1, 2 and 4, the region at the
lower side relative to the vertical middle of the ascending channel
has a larger flow passage area than the region at the upper side in
the cross-sectional shape of the ascending channel in the direction
perpendicular to the drainage direction of flushing water in the
region from the middle of the ascending channel to the downstream
end. However, the flow passage area of the upper side maybe larger
than that of the lower side near the upstream end. The reason for
this is that the ascending channel is not full of flushing water to
the upper surface near the upstream end thereof in many cases with
the result that the shape of the upper surface and the flow passage
area do not affect the flow of flushing water.
[0152] (15) In each of embodiments 1 to 4, the maximum vertical
length gradually increased from the upstream end toward the
downstream side in the cross-sectional shape of the ascending
channel in the direction perpendicular to the drainage direction of
flushing water. However, sewage or the like may only be prevented
from being caught on the bottom top of the downstream end of the
ascending channel, and the cross-sectional shape at a suitable
location of the ascending channel may only be enlarged in the
vertical length than the downstream end.
[0153] (16) Although the introduction passage is formed into the
annular shape in each of embodiments 1 to 4, the introduction
passage may not be annular. In this case, the bottom surface of the
introduction passage may be a descending inclined surface and one
of the right and left side corners may be formed so as to have a
smaller or larger curvature than the other side corner according to
the swirl direction of flushing water.
[0154] (17) Although the ascending channel has a substantially
cup-shaped upstream end in each of embodiments 3 and 4, the
upstream end may not be cup-shaped. In this case, the upstream end
has the shape of an ellipse with a larger lateral dimension than a
longitudinal dimension in the cross-sectional shape of the upstream
end of the ascending channel. Furthermore, a horizontally long
rectangular shape of the upstream end of the ascending channel has
a larger effect than an elliptic sectional shape, and a
substantially cup-shaped sectional shape has a larger effect than
the horizontally long rectangular shape.
[0155] (18) Although the invention is applied to the flush toilet
of the type that a siphon action is caused, in each of embodiments
1 to 4, the invention may be applied to flush toilets of various
flush types. The flush toilet may be of the type that a siphon
action is not caused.
INDUSTRIAL APPLICABILITY
[0156] The present invention is applicable to a flush toilet.
EXPLANATION OF REFERENCE SYMBOLS
[0157] 10, 60 . . . toilet bowl
[0158] 20, 70 . . . introduction passage
[0159] 30, 80, 180 . . . ascending channel
[0160] 31, 81, 181 . . . upstream end
[0161] 31R, 31L, 81D, 81E . . . corner
[0162] 32, 82, 182 . . . bottom top
[0163] 33, 183 . . . channel bottom
[0164] 35, 186, 187, 188 . . . upper surface
[0165] 40, 90 . . . descending channel
[0166] 41, 141 . . . ledge
[0167] 144 . . . rear surface
[0168] 184, 185 . . . rising surface
* * * * *