Water dispenser abstract
In a water dispenser for feeding small animals comprising a casing,
water supply means having an outlet, valve means for controlling
water feed disposed in the outlet, and a water feed tube, the valve
means comprises: an elastic valve seat member having an annular
disk portion constituting the valve seat and a cylindrical portion
formed coaxially and integrally with the disk portion; a poppet
valve normally closed against the valve seat and fixed to the upstream
end of the feed tube, which, upon being nudged and moved at its
downstream end by a small animal, opens the poppet valve to permit
water from the supply means to enter the cylindrical portion of
the valve and then into the feed tube; and a coil spring fitted
in compressed state around the cylindrical portion to elastically
reinforce the same.
Water dispenser claims
What we claim is:
1. A water dispenser for feeding small animals having upstream
and downstream directions and comprising: a casing supplied with
water and having a water outlet at its downstream part; an elastic
valve seat sealingly secured in said water outlet and having an
upstream planar surface; a poppet valve having a valve surface normally
engaging said planar surface in a water-tight manner; a feed tube
secured at its upstream end to said poppet valve and extending downstream
through said valve seat away from said casing, whereby when said
feed tube is inclined by a nudging force applied by a small animal
to the downstream end of said tube, said poppet valve is also inclined
relative to said valve seat to allow the water in the casing to
flow downstream through a gap formed between said valve seat and
said poppet valve; means forming an annular water receiving space
for temporarily receiving therein the water which has flowed through
said gap; aperture means formed through said feed tube to conduct
the water in said water receiving space into the interior of said
feed tube to cause the water to flow downstream therein, said valve
seat comprising an annular flange providing said planar surface
and a cylindrical portion which is open at an upstream end and terminates
at a downstream end wall, said feed tube extending downstream through
the interior of said cylindrical portion with an annular space interposed
therebetween and forming said water receiving space, said feed tube
extending further downstream through a tight hole in said end wall,
whereby water cannot leak between said feed tube and said end wall,
said aperture means being formed in the part of the feed tube located
in said cylindrical portion and a position upstream and remote from
said end wall; and a coil spring fitted in compressed state encompassingly
about said cylindrical portion and reinforcingly supporting from
outside said cylindrical portion of the valve seat, the cylindrical
portion having a downstream end wall part of enlarged outer diameter,
forming an annular shoulder against which a portion of said coil
spring abuts, the portion of the coil spring, adjacent to said annular
flange, being in abutment with the annular flange whereby an axial
tension is exerted to the cylindrical portion by the coil spring.
2. A water dispenser according to claim 1 in which the upstream
and downstream directions are substantially vertical during the
use of the dispenser, the axes of the feed tube, the poppet valve,
the water receiving space and the cylindrical portion, being substantially
vertical, and which further comprises a water supplying reservoir
secured to the upper part of the casing and having an internal chamber
for storing drinking water.
3. A water dispenser according to claim 1 in which said part of
enlarged diameter is formed by elastic deformation of the end wall
part in radially outward direction due to the fact that the inner
diameter of downstream end wall part is smaller than the outer diameter
of the water feed tube passed through the downstream end wall part.
4. A water dispenser according to claim 3 in which the coil spring
has a coil diameter at an intermediate part thereof, which diameter
is less than the coil diameter at other parts of the coil spring,
the intermediate part being in abutting relation to the annular
shoulder of the cylindrical portion.
5. A water dispenser according to claim 1 further comprising a
guard tube encompassing and extending along said feed tube and fixed
at the upstream end thereof to said casing, whereby the feed tube
is protected against undue external forces and its lateral inclining
movement is limited.
6. A water dispenser according to claim 5 in which the upstream
and downstream directions are substantially horizontal during the
use of the dispenser, the axes of the feed tube, the poppet valve,
the water receiving space, and the cylindrical portion being substantially
horizontal, at least the guard tube being inclined slightly upwardly
in the downstream direction, and is mounted with the upstream and
downstream parts thereof respectively disposed outside and inside
of a vertical wall of an enclosure for housing one or more small
animals.
7. A water dispenser according to claim 6 further comprising a
flow control rod inserted in the feed tube to prevent excessive
rushing of water therethrough, the guard tube being adapted to catch
spilt or unused water dripping from the downstream end of the feed
tube and to discharge said water through a drain hole disposed outside
of said enclosure.
Water dispenser description
BACKGROUND OF THE INVENTION
This invention relates generally to water dispensers for feeding
small animals, and more particularly to an improved type thereof
specifically adapted for feeding mice and rats.
Automatic feeding of drinking water to experimental animals is
essential for labor-saving breeding of these animals and for providing
a supply of drinking water at all times.
Among water dispensers for various small animals and birds, those
for the mice and rats are technically most retarded, and very few
of the devices proposed heretofore have been acceptable for general
use. The reason for this is that a large number of water dispensers
are required since mice and rats constitute a majority of the experimental
animals. This requirement inevitably necessitates a simplified construction
of water dispensers which can be produced at a substantially low
cost.
Despite this necessity for low-cost construction, however, requirements
such as prevention of water leakage, sterile state of the water
dispenser, and provision of sensitivity in operation are more strict
than those for the water dispensers for other animals and birds.
These requirements arise from the requirement that the care of these
animals be almost completely free of labor such as bed cleaning
and drying and the requirement that the drinking water be readily
supplied upon application of a weak nudging force of the mice and
rats against a part of the water dispenser but can be instantaneously
stopped upon removal of the same force with some amount of the water
always kept in a part of the dispenser so that the animal can easily
find the part to be nudged.
A further problem arises from the fact that, in the most successful
water dispensers of the instant character known heretofore, at least
one vital part is made of a flexible, elastic material such as a
synthetic rubber. In the operation of the dispenser, this elastic
part is called upon to undergo a large number of repeated deflections
and deformations due to repeated stress, which will give rise to
deterioration of the elastic property of the material if it is not
elastically reinforced. Furthermore, all parts of the water dispenser
must be periodically sterilized at high temperature and pressure,
most conveniently with steam. This further hastens the deterioration
of the elastic material.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is to provide a water
dispenser for feeding small animals of simple construction and low
production cost in which a vital elastic part is elastically reinforced
by another elastic structure and thereby caused to have a prolonged
serviceable life.
Another object of the present invention is to provide a water dispenser
for feeding small animals having valve means which is sensitive
in operation, whereby the drinking water can be released by a slight
nudging of the water feed tube.
Still another object of the invention is to provide a water dispenser
for feeding small animals wherein leakage of the drinking water
at the time of closure of the valve is substantially eliminated.
According to this invention, briefly summarized, there is provided
a water dispenser for feeding small animals having upstream and
downstream directions and comprising: a casing supplied with water
and having a water outlet at its downstream part; an elastic valve
seal sealingly secured in said water outlet and having an upstream
planar surface; a poppet valve having a valve surface normally engaging
said planar surface in a water-tight manner; a feed tube secured
at its upstream end to said poppet valve and extending downstream
through said valve seat away from said casing, whereby when said
feed tube is inclined by a nudging force applied by a small animal
to the downstream end of said tube, said poppet valve is also inclined
relative to said valve seat to allow the water in the casing to
flow downstream through a gap formed between said valve seat and
said poppet valve; means forming an annular water receiving space
for temporarily receiving therein the water which has flowed through
said gap; aperture means formed through said feed tube to conduct
the water in said water receiving space into the interior of said
feed tube to cause the water to flow downstream therein, said valve
seat comprising an annular flange providing said planar surface
and a cylindrical portion open at an upstream end and terminating
at a downstream end wall, said feed tube extending downstream through
the interior of said cylindrical portion with an annular space interposed
therebetween and forming said water receiving space, said feed tube
extending further downstream through a tight hole in said end wall,
whereby water cannot leak between said feed tube and said end wall,
said aperture means being formed in the part of the feed tube located
in said cylindrical portion and a position upstream and remote from
said end wall; and an elastic reinforcing structure fitted in compressed
state encompassingly about and reinforcingly supporting at least
said cylindrical portion of the valve seat.
The nature, principle, and utility of the present invention will
be fully understood from the following detailed description with
respect to preferred embodiments of the invention when read in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawing:
FIG. 1 is an elevational view, partly in vertical section, of an
example of a water dispenser of vertical type according to this
invention;
FIG. 2 is an enlarged vertical sectional view of an important part
of the water dispenser shown in FIG. 1;
FIG. 3 is a sectional view similar to FIG. 2 showing the water
dispenser in an operational state wherein the valve means is partly
opened;
FIG. 4 is a further enlarged view, in vertical section, of the
part shown in FIG. 2;
FIG. 5 is an enlarged view, in vertical section, showing principally
an elastic valve seat member;
FIG. 6 is a side view of a spring to be fitted around a lower cylindrical
portion of the valve seat member;
FIG. 7 is a side elevation, in longitudinal section, of another
example of a water dispenser, of horizontal type, according to this
invention;
FIG. 8 is an enlarged side view of a fluted rod to be inserted
in the water feed tube of the water dispenser shown in FIG. 7;
FIG. 9 is a further enlarged cross section of the fluted rod taken
along the plane indicated by line IX--IX in FIG. 8;
FIG. 10 is an enlarged side elevation, in vertical section, of
the valve and valve seat part of the water dispenser shown in FIG.
7; and
FIG. 11 is a view similar to FIG. 10 showing the water dispenser
in an operational state wherein the valve means is partly opened.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1 the example shown therein of the water
dispenser according to the present invention for feeding drinking
water to small animals comprises a casing (or a supporting member)
1 and a water supplying reservoir 2 screw fastened to the upper
part of the casing 1. The reservoir 2 has an internal chamber 3
for storing drinking water, and the lower surface 5 of the bottom
wall of the chamber 3 confronts the bottom surface of a central
recess 4 in the casing 1 when the reservoir 2 is thus fastened
to the casing 1 with a slight gap maintained therebetween. An outlet
port 8 is provided at the center through the bottom wall of the
chamber 3.
As shown in FIGS. 2 and 4 a poppet valve member 7 having a cap-like
portion 7a having a diameter smaller than that of the outlet port
8 and having a T-shaped configuration in vertical section including
a downwardly projecting central stem 7b is inserted in the outlet
port 8 and the central stem 7b is fixedly connected to the upper
end of a water feed tube 6. The casing 1 is further provided with
a screw threaded central hole 10 and a guard tube 9 having a diameter
corresponding to that of the hole 10 and having a threaded portion
at the upper part thereof is screwed into the central hole 10. The
water feed tube 6 is provided with a required number of perforations
12 near the upper end thereof connected to the stem portion 7b of
the valve member 7.
An elastic valve seat member 13 formed into a T-shaped configuration
in vertical section and having an upper flange seat portion 14 and
a downwardly extending cylindrical portion 15 is further provided
to cooperate with the valve member 7 as described hereinafter in
more detail. The outer peripheral portion of the flange porton 14
is firmly clamped in a water-tight manner between the lower surface
5 of the bottom wall of the chamber 3 and the bottom surface of
the central recess 4 and in a manner such that the downwardly extending
cylindrical portion 15 is held concentrically with the outlet port
8 of the chamber 3 and with the poppet valve member 7 received therein.
More specifically, the poppet valve member 7 connected to the water
feed tube 6 is inserted through the central hollow space of the
cylindrical portion 15 of the elastic valve seat member 13 in a
concentric manner such that the lower face 11 of the cap-like portion
7a, which is in this example formed with a peripheral edge slightly
projecting downwardly, contacts the upper planar surface of the
flange portion 14 of the elastic valve seat member 13.
It should be noted that, as shown in FIG. 5 the central hollow
space of the cylindrical portion 15 of the elastic valve seat member
13 is reduced in diameter at the lowermost end thereof so that an
annular end wall 16 is formed and the water feed tube 6 passing
through the cylindrical portion 15 of the valve seat member 13 is
passed through and engages the end wall 16 in a water-tight manner,
and an annular chamber 15b is formed, as shown in FIG. 4 within
the cylindrical portion 15 of the elastic valve seat member 13 around
the water feed tube 6. As clearly indicated in FIG. 5 the inner
diameter of the central hole, defined by the inner wall surface
16a, through the end wall 16 is preferably less, before the water
feed tube 6 is inserted therethrough, than the outer diameter of
this tube 6. This difference in diameters will not only provide
a water-tight fit between the inner surface 16a and the tube 6 but
also tend to enlarge the outer diameter of the end wall 16 as shown
in FIG. 4 to a value somewhat greater than the cylindrical portion
15 at its upper part, whereby an annular shoulder 15c will be formed
around the outer surface at the junction between the cylindrical
portion 15 and the end wall 16. This shoulder 15c has a useful function
as described hereinafter.
At least the cylindrical portion 15 of the elastic valve seat member
13 exclusive of the end wall part 16 is encompassed by an elastic
reinforcing structure, which in the instant example is a coil spring
17. In the illustrated example, this coil spring 17 in its assembled
state, extends from the bottom surface of the flange portion 14
of the member 13 to the lower end of the end wall 16. As best shown
in FIG. 6 this coil spring 17 is of substantially the same coil
diameter D.sub.1 at its upper and lower ends but has a constricted
intermediate part 17a of a diameter D.sub.2 which is somewhat less
than the diameter D.sub.1. When the coil spring 17 is fitted on
the cylindrical portion 15 in assembled state, it is in a compressed
state, which is maintained by its abutment at its upper end against
the lower surface of the flange portion 14 and by its firm constriction
at its intermediate part 17a around the lower part 15a of the cylindrical
portion 15 immediately above the aforedescribed shoulder 15a at
the upper end of the end wall 16.
Because of the relatively small diameter D.sub.2 of the intermediate
part 17a of the spring 17 this lower part 15a is somewhat constricted
by the inner surface of the part 17a to assume a depressed waisted
shape. This waisted depression, together with the shoulder 15c,
effectively functions to fixedly hold the intermediate part 17a
of the spring 17. At other parts of the diameter D.sub.1 of the
coil spring 17 above and below the intermediate part 17a, the spring
17 is fitted somewhat loosely around or is clear of the cylindrical
portion 15 or the end wall 16.
The coil spring 17 functions to assist the elastic cylindrical
portion 15 of the valve seat member 13 in exerting a downward force
on the cap-like portion 7a of the poppet valve member 7 (or exerting
an upward force on the flange portion 14) tending to keep the lower
surface 11 of the cap-like portion 7a in tight intimate contact
with the upper surface of the flange portion 14 of the valve seat
member 13 when the valve member 7 is in its normally closed state.
This function of the coil spring 17 is important particularly when
the silicone rubber valve seat member 13 loses some of its elasticity
after a great number of sterilizations with steam.
Another function of the coil spring 17 is to reinforcingly hold
the lower part of the cylindrical portion 15 and end wall 16 of
the valve seat member 13 thereby to deter cracking or tearing of
these parts and, in the event that cracks or tears should develop,
to prevent them from spreading.
In the water dispenser of the above described construction, the
elastic valve seat member 13 is made of a heat-resistant and water-resistant
material having the required elasticity such as a synthetic rubber,
preferably a silicone rubber. All other parts are preferably made
of 18-8 stainless steel so that they can withstand repeated sterilization
with steam and resist corrosion.
For actual use, the water dispenser is secured to an appropriate
member in a cage of the mice or rats, and water is supplied into
the chamber 3 within the water supplying reservoir 2. In this state,
the flowing down of the water is stopped by the poppet valve member
7 with the lower surface 11 of the poppet valve member 7 engaging
the upper planar surface of the elastic valve seat member 13.
When the lower end of the water feed tube 6 is touched by small
animals such as mice and rats, the water feed tube 6 is thereby
inclined as shown in FIG. 3 against the resilient force of the elastic
valve seat member 13. The cap-like portion 7a of the poppet valve
member 7 at the upper end of the water feed tube 6 is thereby inclined
relative to the upper planar surface of the valve seat member 13
thus forming a narrow gap on one side thereof between the lower
surface 11 of the cap-like portion 7a and the upper surface of the
valve seat member 13. Water in the chamber 3 is thus passed through
the narrow gap into the annular space 15b formed within the cylindrical
portion 7b of the valve seat member 13. The water is then passed
through the apertures 12 to the interior of the water feed tube
6 and thereafter toward the lower end of the water feed tube 6.
Since the lower end wall 16 of the cylindrical portion 15 of the
valve seat member 13 engages the circumferential wall of the water
feed tube 6 in an water-tight manner, any leakage of water through
this part is completely eliminated. Furthermore, the sizes of the
poppet valve 7 apertures 12 and the inner diameter of the water
feed tube 6 are so selected that the flowrate of the water flowing
through the water feed tube 6 at the time when the lower end thereof
is touched by a mouse or rat becomes suitable for normal drinking
of the water by the mouse or rat. In this manner, the possibility
of the water being spilled onto the cage bed can be substantially
eliminated.
When the animal ceases to nudge the lower end of the water feed
tube 6 the poppet valve instantaneously stops the water flow. In
this case, however, the water filling the interior of the water
feed tube or at least the space formed in the cylindrical portion
15 of the valve seat member 13 is retained even after the closure
of the valve means. A mouse or rat that desires to drink water senses
the water vapor coming from the lower end of the water feed tube
6 and nudge the end as described above.
The guard tube 9 protects the water feed tube 6 from any mechanical
damage, and limits lateral movements of the water feed tube 6. When
it is desired to readjust the contact pressure between the cap-like
portion 7a of the valve member 7 and the valve seat member 13 the
water feed tube 6 can be slightly pushed into or pulled out of the
cylindrical portion 15 of the valve seat member 13.
In another embodiment of this invention as illustrated in FIGS.
7 through 11 the water dispenser is adapted for use in a substantially
horizontal state with its valve mechanism disposed outside a vertical
wall 31 of a cage or pen housing one or more small animals and with
its water-dispensing end disposed inside the vertical wall 31. In
actual use, the water dispenser is mounted with a slight inclination
as indicated by a small angle .alpha., that is, the axis of the
dispenser is downwardly sloped from the water-dispensing end toward
the valve mechanism. The purpose of this inclination is described
hereinafter.
This water dispenser has a casing (or a supporting member) 19 of
the shape of a cylindrical cup or screw socket comprising a cylindrical
wall part 19a with a tapped inner surface and an end wall part 19b
with a central tapped hole. A nipple-like screw fitting 18 having
a recessed cavity 18a at its inner end and a central through hole
18b communicating with the cavity 18a and the open inner end of
the fitting 18 is screwed into the cylindrical wall part 19a of
the casing 19. When this screw fitting 18 is thus fully screwed
into the casing, its inner end abuts against an annular elastic
washer 20 coaxially contacting the flange part 22 of an elastic
valve seat member 21 which is in contact on its opposite side with
the above mentioned end wall part 19b of the casing 19. The washer
20 and the flange part 22 of the valve seat member 21 are thereby
clamped between the screw fitting 18 and the casing 19.
The outer threaded end of a guard tube 30 is screwed into the above
mentioned central tapped hole of the end wall part 19b of the casing
19. A nut 26 is also screw engaged with the threaded end of the
guard tube 30 to lock the screw engagement between guard tube 30
and the casing 19. A semicylindrical cutout 30a is formed at the
inner or downstream end of the guard tube 30 so as to expose the
inner or downstream end of a feed tube 27 to nudging action by a
small animal. The extreme inner end 30b of the guard tube 30 which
is not thus cut out extends inward beyond the inner end of the feed
tube 27 and thus protects the feed tube. This extreme inner end
30b also serves as a drip pan to catch excess or unused water dripping
from the inner end of the feed tube 27.
The elastic valve seat member 21 comprising the flange part 22
a cylindrical stem part 23 and an end wall part 24 as shown in
FIG. 10 is similar to the valve seat member 13 in the preceding
embodiment of the invention. A coil spring 29 also similar to the
coil spring 17 in the preceding example is provided around the stem
part 23 and the end wall part 24. Detailed description relating
to the valve seat member 21 and the coil spring 29 will be omitted
because of the above mentioned similarities.
A valve 25 of conical shape is provided to function similarly as
the valve 7 in the preceding example but is fixed directly to the
outer or upstream end of a water feed tube 27 which is similar
to the water feed tube 6 of the preceding example and functions
as a valve stem. This water feed tube 27 is provided therein with
a feed control rod 28 as shown in FIGS. 8 and 9 which has a function
similar to that of a so-called feed in a fountain pen for flow control.
That is, this water dispenser is supplied with water from a source
32 of water, such as tap-water supply, by way of a pressure reducing
valve 33 as indicated in FIG. 7 and, although the source water
pressure is reduced somewhat by the valve 33 the water is apt to
rush through the feed tube 27 and gush out wastefully into cage
and onto the cage bed when the valve 25 is opened unless its flow
is controlled by means such as the feed control rod 28.
This feed control rod 28 is of a diameter such that the space formed
between it and the inner wall surface of the feed tube 27 is of
suitable capillary dimension. Three or more discontinuous grooves
28a are formed in this feed control rod 28 in the longitudinal direction
thereof. These grooves 28a, which may be omitted if desired, have
been found to add to the effectiveness of the feed control. The
rod 28 can be retained in the feed tube 27 by any of various means.
A very simple measure for this purpose, as indicated in FIG. 10
is to bend the rod 28 slightly before inserting it into the feed
tube 27 thereby to cause it to be retained in the feed tube by friction.
In certain cases, the water supplied from the water source 32 may
contain impurities, which would impair the operation of water dispenser.
Accordingly, a filtering device 35 is provided at the inlet to the
cavity 18a of the screw fitting 18 and is held in place by a spacer
36. A pressure relief valve (not shown) may be provided in the water
supply line at a point upstream from this filter device 35 in order
to prevent excessive pressure buildup on the filter device in the
event that it should become clogged with impurities. This precaution
may be unnecessary since the water dispenser is ordinarily cleaned
and sterilized quite frequently.
The operation of the water dispenser of the above described construction
is similar to that of the preceding embodiment of this invention.
That is, when a small animal in the cage to the left of the wall
31 in FIG. 7 nudges the inner end of the rod 28 and/or the feed
tube 27 the moment exerted on the feed tube 27 causes the valve
25 to tilt relative to the valve seat surface of the valve seat
member 21 whereby water supplied into the cavity 18a passes through
the resulting gaping gap between the valve 25 and its seat into
the space between the feed tube 27 and the feed control rod 28 and
travels to the inner end of the feed tube 27.
Any excess or unused portion of the water thus fed drops downward
from the inner end of the feed tube 27 onto the lower part of the
interior of the guard tube 30 at its extreme inner end 30b. The
water thus caught by the guard tube 30 and prevented from dripping
onto the bed or floor of the cage flows outward along the bottom
part of the guard tube 30 as indicated by arrows, because of the
aforedescribed inclination of the water dispenser, and flows out
of the guard tube 30 through a drain hole 30c at a point outside
of the cage.
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