U.S. patent application number 15/529922 was filed with the patent office on 2018-02-15 for water discharging device.
The applicant listed for this patent is TOTO LTD.. Invention is credited to Masanobu KANASHIRO, Kensuke MURATA, Hitoshi NAKAO, Yutaro OHARA.
Application Number | 20180044898 15/529922 |
Document ID | / |
Family ID | 56977180 |
Filed Date | 2018-02-15 |
United States Patent
Application |
20180044898 |
Kind Code |
A1 |
OHARA; Yutaro ; et
al. |
February 15, 2018 |
WATER DISCHARGING DEVICE
Abstract
A water discharging device 2 that is installed so as to secure a
predetermined opened space between a bowl 3 and the water
discharging device 2, and discharges water toward this bowl 3, the
water discharging device having a water discharge part 13 that jets
waterdrops so as to spread the waterdrops at a predetermined angle
.theta. from a water discharge port 13a, and is set so as to
discharge water at a predetermined flow rate, wherein an average
flow speed X (m/sec) and an average particle size Y (.mu.m) of the
waterdrops jetted from the water discharge part 13 satisfy a
conditional expression of "Y.ltoreq.9300.times.X.sup.(-1.5)".
Inventors: |
OHARA; Yutaro;
(Kitakyushu-shi, Fukuoka, JP) ; MURATA; Kensuke;
(Kitakyushu-shi, Fukuoka, JP) ; KANASHIRO; Masanobu;
(Kitakyushu-shi, Fukuoka, JP) ; NAKAO; Hitoshi;
(Kitakyushu-shi, Fukuoka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOTO LTD. |
Kitakyushu-shi, Fukuoka |
|
JP |
|
|
Family ID: |
56977180 |
Appl. No.: |
15/529922 |
Filed: |
November 20, 2015 |
PCT Filed: |
November 20, 2015 |
PCT NO: |
PCT/JP2015/082762 |
371 Date: |
May 25, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E03C 1/042 20130101;
E03C 2001/0414 20130101; E03C 1/08 20130101 |
International
Class: |
E03C 1/042 20060101
E03C001/042; E03C 1/08 20060101 E03C001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2015 |
JP |
2015-064229 |
Claims
1. A water discharging device that is provided so as to secure a
predetermined opened space with respect to a water receiving part,
and discharges water toward the water receiving part, the water
discharging device comprising, a water discharge part that jets
waterdrops so as to spread the waterdrops at a predetermined angle
from a water discharge port, and is set so as to discharge water at
a predetermined flow rate, wherein an average flow speed X (m/sec)
and an average particle size Y (.mu.m) of the waterdrops jetted
from the water discharge part satisfy a following conditional
expression (1). Y.ltoreq.9300.times.X.sup.(-1.5) (1)
2. The water discharging device according to claim 1, wherein the
average flow speed X and the average particle size Y of the
waterdrops jetted from the water discharge part further satisfy a
following conditional expression (2). Y.gtoreq.-360.times.X+1500
(2)
3. The water discharging device according to claim 1, wherein the
average flow speed X of the waterdrops jetted from the water
discharge part is equal to or larger than 1.7 (m/sec).
4. The water discharging device according to claim 1, wherein the
average particle size Y of the waterdrops jetted from the water
discharge part is equal to or larger than 35 (.mu.m).
5. The water discharging device according to claim 1, wherein the
average particle size Y of the waterdrops jetted from the water
discharge part is equal to or smaller than 9000 (.mu.m).
6. The water discharging device according to claim 1, wherein the
water discharge part jets the waterdrops so as to spread the
waterdrops at from 40 to 50 degrees as the predetermined angle.
Description
TECHNICAL FIELD
[0001] The present invention relates to a water discharging device,
and more particularly to a water discharging device that discharges
water so as to spread the water from a water discharge port.
BACKGROUND ART
[0002] Conventionally, various attempts are made for saving water
in a water discharging device. Among these, spray water discharge
in which misty water is discharged at a low flow rate (water is
discharged in such a manner that water spreads from a water
discharge port) is effective for water saving. This spray water
discharge is useful in being capable of discharging water over a
wide range while saving water.
[0003] For example, Patent Document 1 discloses a configuration of
a nozzle for the above spray water discharge. Additionally, for
example, Patent Document 2 discloses a hand wash basin that
performs spray water discharge of electrolyzed water having a
sterilizing function to sterilize hands.
CITATION LIST
Patent Document
[0004] Patent Document 1: Japanese Patent Laid-Open No.
2004-050121
[0005] Patent Document 2: Japanese Patent Laid-Open No.
11-241381
SUMMARY OF INVENTION
Technical Problem
[0006] The above spray water discharge is effective for water
saving, but has a higher flow speed than general water discharge
(for example, foamy water discharge, shower water discharge, and
the like), and therefore is likely to cause water splash.
Therefore, the inventors of the present invention have considered
to find out a parameter involved in water splash in the spray water
discharge and implement spray water discharge that does not cause
the water splash.
[0007] The present invention has been made in order to solve the
above problem, and an object of the present invention is to
suitably inhibit water splash in a water discharging device that
discharges water so as to spread the water from a water discharge
port.
Solution to Problem
[0008] In order to achieve the above object, the present invention
is a water discharging device that is provided so as to secure a
predetermined opened space with respect to a water receiving part,
and discharges water toward the water receiving part, the water
discharging device includes a water discharge part that jets
waterdrops so as to spread the waterdrops at a predetermined angle
from a water discharge port, and is set so as to discharge water at
a predetermined flow rate, wherein an average flow speed X (m/sec)
and an average particle size Y (.mu.m) of the waterdrops jetted
from the water discharge part satisfy a following conditional
expression (1).
Y.ltoreq.9300.times.X.sup.(-1.5) (1)
[0009] In the present invention thus configured, in the water
discharging device that jets the waterdrops toward the water
receiving part so as to spread the waterdrops at the predetermined
angle from the water discharge port, the average flow speed and the
average particle size of the waterdrops jetted from the water
discharge part satisfy the above conditional expression (1), and
therefore it is possible to suitably inhibit water splash by the
waterdrops jetted from the water discharge part while securing
water saving and water discharge over a wide range.
[0010] In the present invention, the average flow speed X and the
average particle size Y of the waterdrops jetted from the water
discharge part further satisfy a following conditional expression
(2).
Y.gtoreq.-360.times.X+1500 (2)
[0011] In the present invention thus configured, the average flow
speed and the average particle size of the waterdrops jetted from
the water discharge part satisfy the above conditional expression
(2), and therefore it is possible to secure suitable washing
performance (such as hand washing performance) by water discharge
of the water discharge part.
[0012] In the present invention, the average flow speed X of the
waterdrops jetted from the water discharge part is equal to or
larger than 1.7 (m/sec).
[0013] In the present invention thus configured, the average flow
speed of the waterdrops jetted from the water discharge part is 1.7
(m/sec) or more, and therefore it is possible to suitably implement
a water discharge form in which the waterdrops are jetted so as to
spread at the predetermined angle from the water discharge
port.
[0014] In the present invention, the average particle size Y of the
waterdrops jetted from the water discharge part is equal to or
larger than 35 (.mu.m).
[0015] In the present invention thus configured, the average
particle size of the waterdrops jetted from the water discharge
part is 35 (.mu.m) or more, and therefore the waterdrops jetted
from the water discharge part can be suitably lowered without
floating. Consequently, the waterdrops jetted from the water
discharge part can suitably reach, for example, an object such as
hands of a user which stretch out toward the water discharge
part.
[0016] In the present invention, the average particle size Y of the
waterdrops jetted from the water discharge part is equal to or
smaller than 9000 (.mu.m).
[0017] In the present invention thus configured, the average
particle size of the waterdrops jetted from the water discharge
part is 9000 (.mu.m) or less, and therefore it is possible to
suitably inhibit split of the waterdrops jetted from the water
discharge part on the way. Consequently, it is possible to easily
perform control for inhibiting water splash.
[0018] In the present invention, the water discharge part jets the
waterdrops so as to spread the waterdrops at from 40 to 50 degrees
as the predetermined angle.
[0019] In the present invention thus configured, an angle
corresponding to a range when water is discharged from the water
discharge port (discharge angle) is set to 40 to 50 degrees, and
therefore whole hands of a user can be covered by water discharge
from the water discharge part, and hand washing performance can be
improved.
Advantageous Effects of Invention
[0020] According to the present invention, in a water discharging
device that jets waterdrops so as to spread the waterdrops from a
water discharge port, waterdrops having suitable flow speeds and
particle sizes are jetted, so that it is possible to suitably
inhibit water splash.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a perspective view of a hand wash basin to which a
water discharging device according to the embodiment of the present
invention is applied, as viewed obliquely from above.
[0022] FIGS. 2A and 2B are diagrams for specifically illustrating a
configuration of the water discharging device according to the
embodiment of the present invention, in which FIG. 2A is a
perspective view of this water discharging device as viewed
obliquely from below, and FIG. 2B is a sectional view of this water
discharging device taken along the line IIB-IIB in FIG. 2A.
[0023] FIG. 3 is a longitudinal sectional view of a water discharge
part for illustrating a principle of spray water discharge of the
water discharge part according to the embodiment of the present
invention.
[0024] FIG. 4 is a whole configuration diagram of a measurement
system used to measure water splash in the embodiment of the
present invention.
[0025] FIGS. 5A and 5B each are a diagram illustrating an example
of a measurement result obtained by the measurement system
according to the embodiment of the present invention.
[0026] FIGS. 6A and 6B each are a diagram illustrating another
example of a measurement result obtained by the measurement system
according to the embodiment of the present invention.
[0027] FIG. 7 is an explanatory diagram of an upper limit boundary
line of the average flow speed and the average particle size of
waterdrops jetted from the water discharging device according to
the embodiment of the present invention.
[0028] FIG. 8 is an explanatory diagram of a lower limit boundary
line of the average flow speed and the average particle size of
waterdrops jetted from the water discharging device according to
the embodiment of the present invention.
[0029] FIG. 9 is a diagram illustrating a water discharge form by
the water discharging device in a case where a flow rate applied to
the water discharging device according to the embodiment of the
present invention is variously changed.
[0030] FIG. 10 is an explanatory diagram of a suitable range of the
average flow speed and the average particle size of the waterdrops
jetted from the water discharging device according to the
embodiment of the present invention.
[0031] FIG. 11 is a perspective view of a kitchen as viewed
obliquely from above, the kitchen being a kitchen to which a water
discharging device according to a modification in the embodiment of
the present invention is applied.
DESCRIPTION OF EMBODIMENTS
[0032] Hereinafter, a water discharging device according to the
embodiment of the present invention will be described with
reference to the attached drawings.
Device Configuration
[0033] First, a configuration of the water discharging device
according to the embodiment of the present invention will be
described with reference to FIG. 1 to FIG. 3.
[0034] FIG. 1 is a perspective view of a hand wash basin to which
the water discharging device according to the embodiment of the
present invention is applied, as viewed obliquely from above. As
illustrated in FIG. 1, a hand wash basin 1 mainly has a water
discharging device 2 that mistily performs water discharge (spray
water discharge/misty water discharge) so as to spread water from a
water discharge port as illustrated by reference numeral M, and a
bowl 3 that receives the water discharged from this water
discharging device 2, and drains the water from a drain port (not
illustrated), and serves as a water receiving part.
[0035] FIGS. 2A and 2B are diagrams for specifically illustrating
the configuration of the water discharging device according to the
embodiment of the present invention. FIG. 2A is a perspective view
of the water discharging device according to the embodiment of the
present invention as viewed obliquely from below, and FIG. 2B is a
sectional view of this water discharging device taken along the
line IIB-IIB in FIG. 2A.
[0036] As illustrated in FIGS. 2A and 2B, the water discharging
device 2 has a water discharge pipe 11 that is a curved tubular
member. In a front end of the water discharge pipe 11, a
nozzle-like water discharge part 13 configured to perform spray
water discharge (misty water discharge) in which water spreads at a
predetermined angle from a water discharge port 13a, and a sensor
14 that detects an object to be detected by utilizing infrared
light or the like are disposed. Additionally, inside the water
discharge pipe 11, a flow path 15 that is connected to the water
discharge part 13, and supplies water to the water discharge part
13 is disposed. The water discharging device 2 detects the object
to be detected such as a human body by use of the sensor 14 to
switch between execution and stop of water discharge from the water
discharge part 13.
[0037] Now, a principle of the spray water discharge of the water
discharge part 13 according to this embodiment will be described
with reference to FIG. 3. FIG. 3 is a schematic diagram obtained by
enlarging a longitudinal sectional view of the water discharge part
13 as viewed along the water flow direction.
[0038] As illustrated in FIG. 3, in the water discharge part 13, a
straight flow (refer to the arrow A11) is generated inside an
internal flow path 13d by water that flows in from an inflow port
13b provided in an upper end, and a rotational flow (refer to the
arrow A12) is generated inside the internal flow path 13d by water
that flows in from a slit part 13c formed on an outer peripheral
surface of the upper end of the internal flow path 13d. The spray
water discharge is performed in a full-cone manner from the water
discharge port 13a formed in a lower end of the internal flow path
13d, by a synergistic effect of such a straight flow and such a
rotational flow. More specifically, while spreading in a range
larger than the cross-sectional area (opening diameter) of the
water discharge port 13a, the water is intermittently discharged,
in other words, waterdrops are jetted. In this case, as illustrated
in FIG. 3, water spreads at a predetermined discharge angle .theta.
from the water discharge port 13a to be discharged. For example,
this discharge angle .theta. may be set to 40 to 50 degrees to
cover a whole of hands of a user by the spray water discharge from
the water discharge part 13.
[0039] As described above, in this specification, word "spray water
discharge" means that water is intermittently discharged so as to
spread at the predetermined angle .theta. from the water discharge
port 13a of the water discharge part 13, in other words, waterdrops
are jetted.
[0040] The water discharge port 13a of the water discharge part 13
has a cross-sectional area smaller than a water discharge port of a
general water discharge part (for example, a water discharge part
for performing foamy water discharge or shower water discharge),
and therefore has strong resistance, and generates pressure
reducing action. Therefore, at least one of a constant flow valve,
a pressure regulating valve, and a constant-pressure valve may be
provided on an upstream side of the flow path 15 of the above water
discharging device 2 (not illustrated in FIGS. 2A and 2B), and
water may be supplied to the water discharge part 13 at a
predetermined flow rate and/or with predetermined pressure. These
valves are suitably adjusted, so that the flow speed and the
particle size (strictly, the average flow speed and the average
particle size) in the spray water discharge from the water
discharge part 13 are set to respective desired values.
[0041] In the above example, an automatic water discharging device
that detects an object to be detected such as a human body by using
the sensor 14 to automatically switch between water discharge and
stop of the water discharge is described as the water discharging
device 2 (refer to FIGS. 2A and 2B). However, the present invention
is not limited to application to such an automatic water
discharging device, and can be applied to a water discharging
device that manually performs water discharge and stop of the water
discharge.
Flow Speed and Particle Size of Spray Water Discharge
[0042] Now, the flow speed and the particle size of the spray water
discharge by the water discharge part 13 of the water discharging
device 2 according to the embodiment of the present invention will
be described. More specifically, the average flow speed and the
average particle size of waterdrops jetted from the water discharge
part 13, which are to be applied to the water discharging device 2
according to this embodiment, will be described. The inventors of
the present invention investigate ranges of the average flow speed
and the average particle size of waterdrops that are to be jetted
from the water discharge part 13 of the water discharging device 2
by conducting various measurement described below.
[0043] Herein, for the "average flow speed" of the waterdrops
jetted from the water discharge part 13 of the water discharging
device 2, the average flow speed at a position separated from the
water discharge port 13a of the water discharge part 13 by 100 (mm)
is used. The "average flow speed" of the waterdrops is equivalent
to the moving speed of the waterdrops. On the other hand, for the
"average particle size" of the waterdrops jetted from the water
discharge part 13 of the water discharging device 2, a Sauter
average value (total volume/total surface area) based on a particle
size distribution, which is obtained by a Fraunhofer analysis
method utilizing a He--Ne laser is used. This "average particle
size" of the waterdrop is equivalent to the diameter of the
waterdrop.
[0044] The reason why such "average flow speed" and such "average
particle size" are used is because there is a distribution in each
of the flow speeds and the particle sizes of the waterdrops jetted
from the water discharge part 13, and the flow speeds and the
particle sizes are not uniform.
(1) Upper Limit Boundary Line of Flow Speed and Particle Size
[0045] First, an upper limit boundary line of the average flow
speed and the average particle size of the waterdrops jetted from
the water discharge part 13 of the water discharging device 2
according to this embodiment will be described. This upper limit
boundary line is determined from a viewpoint of inhibiting water
splash by the waterdrops jetted from the water discharge part 13 of
the water discharging device 2 according to this embodiment.
[0046] FIG. 4 is a whole configuration diagram schematically
illustrating a measurement system used in order to measure water
splash in the embodiment of the present invention.
[0047] As illustrated in FIG. 4, a measurement system 50 has a
water discharging device 51 that jets a waterdrop WD, and can
variously set the flow speed and the particle size of this
waterdrop WD, a frosted glass 52 with which the waterdrop WD jetted
from this water discharging device 51 collides, a scale 53 placed
on this frosted glass 52, a high-speed camera 54 that photographs a
range including at least a surface of the frosted glass 52 with
which the waterdrop WD collides, a lighting 55 that irradiates the
frosted glass 52 from above with light, a lighting 56 that
irradiates the frosted glass 52 from below with light, and a PC
(personal computer) 57 that receives supplied image data
photographed by the high-speed camera 54 to process this image
data.
[0048] More specifically, the frosted glass 52 has size of 300
(mm).times.300 (mm).times.5 (mm). Additionally, a water discharge
port of the water discharging device 51 and a surface of the
frosted glass 52 are separated by 100 (mm). The high-speed camera
54 photographs with resolution of 1280 (pixels).times.800 (pixels)
at a high speed of 10000 (frames/second). Furthermore, the pressure
and the flow rate of water supplied to the water discharging device
51 are adjusted, the opening diameter of a water discharge port
applied to the water discharging device 51 is changed, or the width
of a slit applied to the inside of the water discharging device 51
is changed, so that the flow speed and the particle size of the
waterdrop WD jetted from the water discharging device 51 are
changed. The incident angle of the waterdrop WD jetted from the
water discharging device 51 on the frosted glass 52 is
constant.
[0049] Herein, in this embodiment, a water film WF is formed on the
frosted glass 52, and water splash when the waterdrop WD collides
with this water film WF is measured. Not a hand in a dry state at
an initial stage of hand washing (that is, a state where no water
film is formed on a surface of the hand), but a hand in a wet state
at a middle and subsequent stage of the hand washing (that is, a
state where the water film is formed on the surface of the hand) is
assumed, and the hand in this wet state is simulated by the frosted
glass 52 with the water film WF formed thereon, so that water
splash caused in the hand in the wet state is attempted to be
investigated.
[0050] Water splash is more likely to be caused in the dry state
than the wet state. This reason is as follows. In a case where a
collision object is in the dry state, that is, in a state where a
water film is not formed on a surface of the collision object,
frictional force between water and the collision object, adsorption
power of water, and surface tension of water mainly act, so that
water splash is unlikely to be caused. On the other hand, in a case
where the collision object is in the wet state, that is, in a state
where the water film is formed on the surface of the collision
object, the frictional force between water and the collision object
(including the water film) is decreased, pressure generated at the
time of collision escapes toward an external air side (side on
which pressure is low), force generated at this time, which lifts
the water film becomes larger than the surface tension, so that the
water film bursts to be likely to cause water splash.
[0051] Now, the measurement procedure of water splash according to
this embodiment will be described. First, the water film WF is
formed on the frosted glass 52. In this case, the frosted glass 52
is hydrophilic, and therefore water merely flows on the surface, so
that the water film WF is formed. Then, the waterdrop WD is jetted
from the water discharging device 51 toward the frosted glass 52.
In this case, in order to adjust focus related to jetting of the
waterdrop WD from the water discharging device 51 to the frosted
glass 52, a slit of 5 (mm).times.10 (mm) is applied to the water
discharging device 51. From both the two lighting 55, 56, the
frosted glass 52 is irradiated with light, so that the vicinity of
a collision place of the waterdrop WD on the frosted glass 52 is
photographed by the high-speed camera 54 in this state.
[0052] The PC 57 processes an image photographed by the high-speed
camera 54, and obtains the particle size of the waterdrop WD. In
this case, the PC 57 analyzes the photographed image including the
waterdrop WD and the scale 53 to obtain a length on the
photographed image corresponding to 1 (mm) of the scale 53, and the
particle size of the waterdrop WD on the photographed image, so
that the actual particle size of the waterdrop WD is obtained from
a ratio of these two values. Then, the PC 57 processes the image
photographed by the high-speed camera 54 to obtain the flow speed
of the waterdrop WD (equivalent to the moving speed of the
waterdrop WD). In this case, the PC 57 analyzes the photographed
image including the waterdrop WD and the scale 53 to obtain an
actual moving distance (obtained by a method similar to the above
method for obtaining the particle size of the waterdrop WD) from a
distance on the photographed image where the waterdrop WD moves
during the predetermined number of frames, so that the flow speed
of the waterdrop WD is obtained from this actual moving distance.
Then, a measurer visually recognizes the water film WF and the
waterdrop WD included in the photographed image to determine
whether or not water splash occurs by collision of the waterdrop WD
with the water film WF. The "water splash" mentioned herein means
that the waterdrop WD collides with the water film WF, the water
film WF is lifted, the lifted water film WF bursts (splits), and a
waterdrop splashes.
[0053] FIGS. 5A and 5B illustrate examples of a measurement result
obtained by the measurement system 50 according to the embodiment
of the present invention. More specifically, FIGS. 5A and 5B
illustrate examples of photographed images when the particle sizes
of the waterdrop WD are constant, and the flow speeds of the
waterdrop WD are different. More specifically, FIG. 5A illustrates
an example of a photographed image when the flow speed of the
waterdrop WD is 3 (m/sec), FIG. 5B illustrates an example of a
photographed image when the flow speed of the waterdrop WD is 5
(m/sec), and the particle size of the waterdrop WD is fixed to 750
(.mu.m) when these flow speeds are applied. In addition, the
incident angle of the waterdrop WD to the frosted glass 52
(including the water film WF) is fixed to 90 degrees. In each of
FIGS. 5A and 5B, the photographed images are arranged in order from
the left to the right in time series. For convenience of
explanation, images corresponding to the waterdrop WD are circled,
and bars are added to the vicinity of places where water splash
occurs on the images.
[0054] As illustrated in FIG. 5A, it is found that water splash
does not occur (refer to reference numeral A21), in a case where
the flow speed of the waterdrop WD is 3 (m/sec). As illustrated in
FIG. 5B, it is found that water splash occurs (refer to reference
numeral A22), in a case where the flow speed of the waterdrop WD is
5 (m/sec). Consequently, it can be said that water splash is likely
to be caused, when the flow speed of the waterdrop WD becomes
large.
[0055] FIGS. 6A and 6B are diagrams illustrating another example of
a measurement result obtained by the measurement system 50
according to the embodiment of the present invention. More
specifically, FIGS. 6A and 6B illustrate examples of photographed
images when the flow speeds of the waterdrop WD are constant, and
the particle sizes of the waterdrop WD are different. More
specifically, FIG. 6A illustrates an example of a photographed
image when the particle size of the waterdrop WD is 400 (.mu.m),
FIG. 6B illustrates an example of a photographed image when the
particle size of the waterdrop WD is 820 (.mu.m), and the flow
speed of the waterdrop WD is fixed to 4 (m/sec) when the above
particle sizes are applied. In addition, the incident angle of the
waterdrop WD to the frosted glass 52 (including the water film WF)
is fixed to 90 degrees. In each of FIGS. 6A and 6B, the
photographed images are arranged in order from the left to the
right in time series. For convenience of explanation, images
corresponding to the waterdrop WD are circled, and bars are added
to the vicinity of places where water splash occurs on the
images.
[0056] As illustrated in FIG. 6A, it is found that water splash
does not occur (refer to reference numeral A31), in a case where
the particle size of the waterdrop WD is 400 (.mu.m). As
illustrated in FIG. 6B, it is found that water splash occurs (refer
to reference numeral A32), in a case where the particle size of the
waterdrop WD is 820 (.mu.m). Consequently, it can be said that
water splash is likely to be caused, when the particle size of the
waterdrop WD becomes large.
[0057] In this embodiment, the flow speed and the particle size of
the waterdrop WD jetted from the water discharging device 51 were
set to respective various values, and it was measured whether or
not water splash occurs in combinations of various flow speeds and
particle sizes by the above method. The results are illustrated in
FIG. 7.
[0058] FIG. 7 is a diagram illustrating the presence or absence of
water splash measured in the combinations of the various flow
speeds and particle sizes applied to the waterdrop, and a diagram
for illustrating an upper limit boundary line of the average flow
speed and the average particle size of waterdrops jetted from the
water discharging device 2 according to the embodiment of the
present invention.
[0059] In FIG. 7, a horizontal axis represents the flow speed
(m/sec) of the waterdrop, and a vertical axis represents the
particle size (.mu.m) of the waterdrop. More specifically, the
circles drawn by ".largecircle." in FIG. 7 denote a flow speed and
a particle size when it is determined by measurement that water
splash does not occur, and the crosses drawn by ".times." in FIG. 7
denote a flow speed and a particle size when it is determined by
measurement that water splash occurs. By such measurement results,
a region defined by the flow speed and the particle size can be
divided into a region R1 where water splash occurs, and a region R2
where water splash does not occur, by using a curved line L1
illustrated in FIG. 7 as a boundary line. This curved line L1 can
be expressed by the following approximate expression (3) by using a
flow speed x (m/sec) and a particle size y (.mu.m).
y=9300.times.x.sup.(-1.5) (3)
[0060] In this embodiment, the curved line L1 expressed by the
above expression (3) is used as the upper limit boundary line of
the average flow speed and the average particle size of waterdrops
jetted from the water discharging device 2. That is, as a
conditional expression which the average flow speed X (m/sec) and
the average particle size Y (.mu.m) of the waterdrops jetted from
the water discharging device 2 should satisfy, the following
expression (4) based on the expression (3) is used. When such
expression (4) is satisfied by the average flow speed X (m/sec) and
the average particle size Y (.mu.m) of the waterdrops jetted from
the water discharging device 2, it is possible to suitably inhibit
water splash by the waterdrops jetted from the water discharging
device 2.
Y.ltoreq.9300.times.X.sup.(-1.5) (4)
(2) Lower Limit Boundary Line of Flow Speed and Particle Size
[0061] Now, the lower limit boundary line of the average flow speed
and the average particle size of waterdrops jetted from the water
discharge part 13 of the water discharging device 2 according to
this embodiment will be described. This lower limit boundary line
is determined from a viewpoint of securing washing performance
(dirt removing performance/hand washing performance) by the water
discharging device 2 of this embodiment.
[0062] In this embodiment, in order to obtain the above lower limit
boundary line, the following measurement procedure is performed.
First, pseudo-dirt containing ethanol and Sudan Red at a mass ratio
of "6:1" is created. Next, the created pseudo-dirt of 0.2 (cc) is
adhered to a frosted glass with a size of 80 (mm).times.80 (mm).
Then, the frosted glass to which the pseudo-dirt is adhered is left
for a minute, the pseudo-dirt spreads throughout the frosted glass
by its own weight, and thereafter the frosted glass to which the
pseudo-dirt is adhered is heated at 50 (.degree. C.) for two
minutes by a hot plate to be dried. Then, the water discharging
device discharges water toward the center of the frosted glass for
5 seconds. In this case, the water discharge port of the water
discharging device and a surface of the frosted glass are separated
by 80 (mm).
[0063] The frosted glass to which the above water discharge is
performed is heated at 50 (.degree. C.) for a minute by the hot
plate to be dried, and thereafter is put into a Petri dish. Next,
oleic acid of 20 (cc) is dropped in a Petri dish, and the
pseudo-dirt is separated from the frosted glass. Then, oleic acid
and the pseudo-dirt are collected, and put into an exclusive
container of a spectrophotometer to be measured. Then, a dirt
removing ratio (the smaller the value is, the higher the
pseudo-dirt removing degree is) indicating a pseudo-dirt removing
degree is obtained from a value obtained by measurement using this
spectrophotometer. More specifically, first, in order to previously
perform 0 correction of the spectrophotometer, a measured value
obtained when only oleic acid is used is previously obtained, the
frosted glass which is in a state where the above water discharge
is not performed (that is, a state where 100% of the pseudo-dirt of
0.2 (cc) remains) is previously measured, and a measured value
obtained when the dirt removing ratio is a maximum value (100%) is
previously obtained. Then, on the basis of the previously obtained
measured values thus obtained, a dirt removing ratio (decrease
rate) corresponding to a value obtained by measurement using the
exclusive container of the spectrophotometer containing the
collected oleic acid and pseudo-dirt this time is obtained.
[0064] Herein, as water discharge performed to the frosted glass to
which the pseudo-dirt is adhered, spray water discharge by the
water discharging device 2, and foamy water discharge at 2 liters
per minutes were applied, and the measurement results were obtained
by the above procedure under a similar condition. More
specifically, in a case where the spray water discharge is applied,
the flow speeds and the particle sizes of waterdrops jetted by the
water discharging device 2 were variously changed to be measured.
In this case, various types of the water discharge part 13 are
applied to the water discharging device 2 (consequently, the flow
rate by the water discharge part 13 is changed), so that the flow
speeds and the particle sizes of the jetted waterdrops were
changed.
[0065] By thus measurement, in foamy water discharge at 2 liters
per minute, a dirt removing ratio of 22 (%) was obtained. Then,
from measurement results obtained in a case where the above spray
water discharge is used, the flow speed and the particle size when
the same degree of a dirt removing ratio as a dirt removing ratio
of 22 (%) by the foamy water discharge at 2 liters per minute were
extracted. The results are illustrated in FIG. 8.
[0066] FIG. 8 is a diagram illustrating the results of the flow
speed and the particle size in a case where a dirt removing ratio
of about 22 (%) is obtained by spray water discharge, and is a
diagram for illustrating a lower limit boundary line of the average
flow speed and the average particle size of waterdrops jetted from
the water discharging device 2 according to the embodiment of the
present invention.
[0067] In FIG. 8, a horizontal axis represents the flow speed
(m/sec), and a vertical axis represents the particle size (.mu.m).
More specifically, the triangles drawn by ".tangle-solidup." in
FIG. 8 denote the flow speed and the particle size in the case
where a dirt removing ratio of about 22 (%) is obtained. By such
results, relation between the flow speed x (m/sec) and the particle
size y (.mu.m) in the case where a dirt removing ratio of about 22
(%) is obtained can be expressed by the following approximate
expression (5) corresponding to a straight line L2 illustrated in
FIG. 8.
y=-360.times.x+1500 (5)
[0068] In this embodiment, the lower limit boundary line of the
average flow speed and the average particle size of the waterdrops
jetted from the water discharging device 2 is defined by the
straight line L2 expressed by the above Expression (5). That is, as
a conditional expression which the average flow speed X (m/sec) and
the average particle size Y (.mu.m) of the waterdrops jetted from
the water discharging device 2 should satisfy, the following
expression (6) based on the expression (5) is used. When such
expression (6) is satisfied by the average flow speed X (m/sec) and
the average particle size Y (.mu.m) of the waterdrops jetted from
the water discharging device 2, the same degree of a dirt removing
ratio as the dirt removing ratio by the foamy water discharge at 2
liters per minute can be implemented by the spray water discharge
of the water discharging device 2. That is, it is possible to
secure suitable washing performance by the spray water discharge of
the water discharging device 2.
Y.gtoreq.-360.times.X+1500 (6)
(3) Lower Limit Value of Flow Speed
[0069] Now, the lower limit value of the average flow speed of the
waterdrops jetted from the water discharge part 13 of the water
discharging device 2 according to this embodiment will be
described. This lower limit value is determined from a viewpoint of
formation of suitable spray water discharge by the water
discharging device 2 of this embodiment.
[0070] As described above, in this embodiment, a water discharge
form in which water spreads in a range larger than the opening
diameter of the water discharge port 13a of the water discharge
part 13 to be intermittently discharged is applied as the spray
water discharge. Whether or not such spray water discharge is
suitably formed depends on the flow speed (uniquely equivalent to
the flow rate) applied to the water discharging device 2. This will
be specifically described with reference to FIG. 9.
[0071] FIG. 9 is a diagram illustrating a specific example of the
water discharge form by the water discharging device 2 in a case
where the flow rate applied to the water discharging device 2
according to the embodiment of the present invention is variously
changed. FIG. 9 illustrates a photographed image that illustrates a
water discharge form in a case where a flow rate of 0.2 (L/min) is
applied, a photographed image that illustrates a water discharge
form in a case where a flow rate of 0.15 (L/min) is applied, a
photographed image that illustrates a water discharge form in a
case where a flow rate of 0.1 (L/min) is applied, and a
photographed image that illustrates a water discharge form in a
case where a flow rate of 0.05 (L/min) is applied, in order from
the left.
[0072] From FIG. 9, it is found that at flow rates of 0.1 to 0.2
(L/min), suitable spray water discharge is performed by the water
discharging device 2, that is, water spreads in the range larger
than the opening diameter of the water discharge port 13a to be
intermittently discharged. On the other hand, it is found that at a
flow rate of 0.05 (L/min), suitable spray water discharge is not
formed by the water discharging device 2, that is, water does not
spread in the range larger than the opening diameter of the water
discharge port 13a and is not intermittently discharged. This is
because at a low flow rate, a rotational flow (refer to the arrow A
12 in FIG. 3) necessary for forming the suitable spray water
discharge cannot be formed inside the water discharge part 13.
[0073] Therefore, in this embodiment, a flow speed corresponding to
the above flow rate of 0.05 (L/min) is used as a lower limit value
of the average flow speed of the waterdrops jetted from the water
discharge part 13 of the water discharging device 2. In a case
where the opening diameter of the water discharge port 13a of the
water discharge part 13 is 0.8 (mm), a flow speed of about 1.7
(m/sec) is obtained from a cross-sectional area corresponding to an
opening diameter of 0.8 (mm), and a flow rate of 0.05 (L/min)
described above by use of a theoretical formula of "flow
rate=cross-sectional area.times.flow speed". In this embodiment,
1.7 (m/sec) is used as the lower limit value of the average flow
speed of the waterdrops jetted from the water discharging device 2.
When such 1.7 (m/sec) is applied, and the average flow speed of the
waterdrops jetted from the water discharging device 2 is set to be
1.7 (m/sec) or more, suitable spray water discharge can be formed
by the water discharging device 2, that is, water can spread in the
range larger than the opening diameter of the water discharge port
13a to be intermittently discharged.
(4) Lower Limit Value of Particle Size
[0074] Now, a lower limit value of the average particle size of the
waterdrop jetted from the water discharge part 13 of the water
discharging device 2 according to this embodiment will be
described. This lower limit value is determined from a viewpoint of
suitably lowering the waterdrops jetted from the water discharging
device 2 of this embodiment without floating the waterdrops.
[0075] In this embodiment, it is considered to define the lower
limit value of the average particle size by using the following
expression (7) obtained by converting general Stokes' law.
d = 18 .eta. v ( .rho. p - .rho. f ) g ( 7 ) ##EQU00001##
[0076] In the expression (7), "d" denotes a particle size, ".eta."
denotes the viscosity of water, "v" denotes a terminal speed,
".rho..sub.p" denotes the density of water, ".rho..sub.f" denotes
the density of air, and "g" denotes gravitational acceleration. The
terminal speed v is a speed when body force such as gravity and
centrifugal force and drag which depends on a speed are balanced
and are not changed in a case where an object receives the body
force and the drag. In this case, the object singly moves, that is,
even when another object exists, the object moves without being
influenced by another object. In the expression (7), it is assumed
that the speed of a particle traveling vector is zero, and an
object actually freely falls in the gravity direction.
[0077] In this embodiment, in the above expression (7), the
particle size d when terminal speed v.apprxeq.0 is satisfied is
used as the lower limit value of the average particle size. This is
because a state of terminal speed v.apprxeq.0 is equivalent to a
state where the waterdrops jetted from the water discharging device
2 float without lowering. When the terminal speed v is 0, the
expression (7) is not established, and therefore 1 (mm/sec) is
substituted into the expression (7) as the terminal speed v.
Additionally, values of water viscosity .eta., water density
.rho..sub.p, and air density .rho..sub.f when a water temperature
and an air temperature are 5.degree. C. are substituted into the
expression (7). Consequently, a particle size d of about 35 (.mu.m)
is obtained.
[0078] In this embodiment, 35 (.mu.m) thus obtained is used as the
lower limit value of the average particle size of the waterdrops
jetted from the water discharging device 2. When the average
particle size of the waterdrops jetted from the water discharging
device 2 is set to be 35 (.mu.m) or more by applying 35 (.mu.m),
the waterdrops jetted from the water discharging device 2 can be
suitably lowered without floating. Consequently, the waterdrops
jetted from the water discharging device 2 can suitably reach, for
example, hands of a user.
(5) Upper Limit Value of Particle Size
[0079] Now, an upper limit value of the average particle size of
the waterdrop jetted from the water discharge part 13 of the water
discharging device 2 according to this embodiment will be
described.
[0080] According to measurement performed by the inventors of the
present invention, it is found that when the particle size of the
waterdrop jetted from the water discharging device 2 exceeds 9000
(.mu.m), the waterdrop splits without maintaining the particle size
even in a windless state. Thus, when the waterdrops jetted from the
water discharging device 2 split on the way, control becomes
difficult, and water splash cannot be suitably inhibited.
[0081] Therefore, in this embodiment, from a viewpoint of suitably
maintaining the particle sizes of the waterdrops jetted by the
water discharging device 2 so as not to cause the waterdrops to
split, the upper limit value of the average particle size of the
waterdrops jetted from the water discharging device 2 is defined.
More specifically, in this embodiment, from the above measurement
results, the average particle size of the waterdrops jetted from
the water discharging device 2 is set to be 9000 (.mu.m) or less by
using 9000 (.mu.m) as the upper limit value of the average particle
size of the waterdrops jetted from the water discharging device
2.
(6) Suitable Range of Flow Speed and Particle size
[0082] Now, a suitable range of the average flow speed and the
average particle size of the waterdrops jetted from the water
discharge part 13 of the water discharging device 2 according to
this embodiment, in accordance with contents described in the above
(1) to (5) will be described with reference to FIG. 10.
[0083] FIG. 10 is an explanatory diagram of the suitable range of
the average flow speed and the average particle size of the
waterdrops jetted from the water discharging device 2 according to
the embodiment of the present invention. In FIG. 10, a horizontal
axis represents the flow speed (m/sec), and a vertical axis
represents the particle size (.mu.m). More specifically, in FIG.
10, in addition to the curved line L1 and the straight line L2
(refer to FIG. 7 and FIG. 8) described the above (1), (2), a
straight line L3 corresponding to 1.7 (m/sec) which is the lower
limit value of the average flow speed described in the above (3), a
straight line L4 corresponding to 35 (.mu.m) which is the lower
limit value of the average particle size described in the above
(4), a straight line L5 corresponding to 9000 (.mu.m) which is the
upper limit value of the average particle size described in the
above (5) are overlapped.
[0084] As illustrated in FIG. 10, in this embodiment, the flow
speed and the particle size in a range R3 defined by the curved
line L1 and the straight lines L2 to L5 are applied as the average
flow speed and the average particle size of the waterdrops jetted
from the water discharging device 2 so as to satisfy all conditions
described in the above (1) to (5).
Working Effects According to This Embodiment
[0085] Now, working effects of the water discharging device
according to the embodiment of the present invention will be
described.
[0086] According to this embodiment, in the water discharging
device 2 that performs spray water discharge enabling water saving
and water discharge over a wide range, the average flow speed and
the average particle size of the waterdrops jetted from this water
discharging device 2 satisfies the above conditional expression
(4), so that it is possible to suitably inhibit water splash by the
waterdrops jetted from the water discharging device 2.
[0087] According to this embodiment, the average flow speed and the
average particle size of the waterdrops jetted from the water
discharging device 2 satisfy the above conditional expression (6),
so that it is possible to secure suitable washing performance (such
as hand washing performance) by spray water discharge of the water
discharging device 2.
[0088] According to this embodiment, the average flow speed of the
waterdrops jetted from the water discharging device 2 is set to 1.7
(m/sec) or more, so that it is possible to form suitable spray
water discharge by the water discharging device 2. That is, it is
possible to suitably implement a water discharge form in which
water spreads in a range larger than the opening diameter of the
water discharge port 13a to be intermittently discharged.
[0089] According to this embodiment, the average particle size of
the waterdrops jetted from the water discharging device 2 is set to
35 (.mu.m) or more, so that the waterdrops jetted from the water
discharging device 2 can be suitably lowered without floating.
Consequently, the waterdrops jetted from the water discharging
device 2 can suitably reach, for example, hands of a user.
[0090] According to this embodiment, the average particle size of
the waterdrops jetted from the water discharging device 2 is set to
9000 (.mu.m) or less, so that it is possible to suitably inhibit
split of the waterdrops jetted from the water discharging device 2
on the way. Consequently, it is possible to easily perform control
for inhibiting water splash.
[0091] According to this embodiment, the discharge angle .theta.
(refer to FIG. 3) from the water discharge port 13a of the water
discharging device 2 is set to 40 to 50 degrees, whole hands of a
user can be covered by spray water discharge from the water
discharging device 2, and hand washing performance can be
improved.
Modification
[0092] In the above embodiment, the average flow speed and the
average particle size of the waterdrops jetted from the water
discharging device 2 satisfy all the conditions of (1) to (5)
described in the section of <Flow Speed and Particle Size of
Spray Water Discharge>. However, the present invention is not
limited to this. In another example, the average flow speed and the
average particle size of the waterdrops jetted from the water
discharging device 2 may satisfy at least one condition of any of
(1) to (5) (including various combinations of the conditions of (1)
to (5)).
[0093] In the above embodiment, general tap water (city water) is
discharged from the water discharging device 2. However, in place
of this, for example, functional water (that is, disinfected water)
having a disinfecting function such as electrolyzed water may be
discharged. In one example, an electrolysis tank may be provided on
an upstream side of a flow path 15 of a water discharging device 2,
and electrolyzed water generated by this electrolysis tank may be
discharged from a water discharge part 13.
[0094] In the above embodiment, the example in which the present
invention is applied to a hand wash basin (refer to FIG. 1) is
described. However, the application of the present invention is not
limited to this. In another example, the present invention can be
applied to a kitchen.
[0095] FIG. 11 is a perspective view of a kitchen as viewed
obliquely from above, the kitchen being a kitchen to which a water
discharging device according to a modification in the embodiment of
the present invention is applied. A kitchen 5 illustrated in FIG.
11 mainly has a water discharging device 6 that mistily performs
water discharge (spray water discharge/misty water discharge) in
which water spreads from a water discharge port as illustrated by
reference numeral M, a sink 7 that receives the water discharged
from this water discharging device 6 to drain the water from a
drain port (not illustrated), and serves as a water receiving part.
A configuration similar to the configuration of the water
discharging device 2 according to the above embodiment is applied
to the water discharging device 6 of such a kitchen 5, so that
working effects similar to the working effects of the contents
described in the section of <Working Effects according to This
Embodiment> are obtained.
REFERENCE SIGNS LIST
[0096] 1 hand wash basin
[0097] 2, 6 water discharging device
[0098] 3 bowl
[0099] 5 kitchen
[0100] 6 sink
[0101] 11 water discharge pipe
[0102] 13 water discharge part
[0103] 13a water discharge port
[0104] 15 flow path
* * * * *