U.S. patent number 3,856,206 [Application Number 05/382,734] was granted by the patent office on 1974-12-24 for thermosensitive flow control device.
This patent grant is currently assigned to American Standard Inc.. Invention is credited to Edward H. Bell, John R. Bell.
United States Patent |
3,856,206 |
Bell , et al. |
December 24, 1974 |
THERMOSENSITIVE FLOW CONTROL DEVICE
Abstract
A thermosensitive flow control device, which can advantageously
be used in a water spray head, includes a bimetallic snap disc
flexurally movable relative to flow port means in the spray head.
Normally, the snap disc is flexed away from the port means so that
water discharges from the head as a spray; however, when the water
temperature rises above a predetermined magnitude, the snap disc is
flexed toward the port means to retard and diminish, but not
eliminate, the flow therethrough. The water thus discharges from
the head as a dribble until the temperature drops to a
predetermined level, whereupon the disc automatically flexes away
from the port means and the water once again discharges from the
head as a spray.
Inventors: |
Bell; Edward H. (Monogahela,
PA), Bell; John R. (Monogahela, PA) |
Assignee: |
American Standard Inc. (New
York, NY)
|
Family
ID: |
23510187 |
Appl.
No.: |
05/382,734 |
Filed: |
July 26, 1973 |
Current U.S.
Class: |
239/75;
137/468 |
Current CPC
Class: |
B05B
12/10 (20130101); E03C 1/041 (20130101); F16K
31/002 (20130101); F16K 31/003 (20130101); Y10T
137/7737 (20150401) |
Current International
Class: |
B05B
12/08 (20060101); B05B 12/10 (20060101); A62c
037/00 (); A62c 037/34 () |
Field of
Search: |
;239/67,75,456,460
;137/468 ;236/93 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: King; Lloyd L.
Attorney, Agent or Firm: Salerno, Jr.; James J. Crooks;
Robert G.
Claims
What is claimed is:
1. A flow control device which retards flow of a liquid stream when
the stream temperature exceeds a predetermined first temperature
and which restores full flow when the stream temperature drops to
or below a predetermined second and lower temperature, said device
comprising:
a flow head connected to said liquid stream;
flow port means in said head through which said liquid stream
flows;
a temperature responsive disc connected to said flow port means and
positioned a preselected distance therefrom when said stream
temperature is less than said predetermined first temperature, to
permit full stream flow through said flow port means;
said disc having at least a portion thereof free for flexural
movement toward and away from said flow port means with such
flexural movement occurring in response to temperature variations
in said liquid stream;
said disc arranged and constructed to be flexed toward said flow
port means when said stream temperature exceeds said predetermined
first temperature, to partially close said flow port means to
provide a controlled reduced stream flow through said flow port
means;
said disc portion arranged and constructed to be flexed away from
said flow port means and returned to its predetermined spacing at
said preselected distance from said flow port means when said
stream temperature drops to or below said predetermined second and
lower temperature, whereupon full stream flow through said port
means is restored.
2. A flow control device as defined in claim 1 wherein said flow
head is a shower head and wherein said liquid stream is water.
3. A flow control device as defined in claim 2 wherein said flow
port means includes a plurality of individual flow ports spaced
from each other.
4. A flow control device as defined in claim 3 wherein said portion
of said disc which is free for flexural movement comprises the
peripheral margin thereof and wherein said peripheral margin, when
flexed toward said flow port means, partially covers said
individual flow ports.
5. A flow control device as defined in claim 2 wherein said
temperature responsive metallic disc is a unitary bimetallic snap
disc.
6. An improvement as defined in claim 1 wherein said disc includes
a central portion and a peripheral margin portion and wherein
mounting means connect with said disc central portion to position
said disc within said spray head.
7. An improvement as defined in claim 1 wherein said flow port
means includes a plurality of post members, each of which has a
bore formed therein for passage of water, and wherein said
peripheral margin portion abuts against said post members when said
flexural displacement occurs.
8. A flow valve for use in a water distribution system to diminish
but not eliminate water flow when the water temperature rises about
a predetermined magnitude, said flow valve comprising:
a plate member having a first surface adapted to be disposed in the
upstream direction and an opposed second surface adapted to be
disposed in the downstream direction;
a plurality of post members projecting outwardly from said first
surface of said plate member;
means forming a plurality of bores, one extending through each of
the post members and through said plate member to form a plurality
of flow ports by which water from said upstream direction can flow
through said posts and said plate member to pass to said downstream
direction;
a thermosensitive bimetallic snap disc;
means connecting the center of said snap disc with said first
surface of said plate member;
said snap disc being flexural in response to temperature variations
and hence movable from a first or full flow permitting position to
a second or flow diminishing position;
said snap disc having a peripheral margin spaced from said post
members in said first position and abutted against said post
members in said second position;
said snap disc normally being disposed in said first position to
permit full flow around said disc and through said bores;
said snap disc being flexed when said water temperature rises above
said predetermined magnitude to said disc to move to said second
position and to cause said peripheral margin to abut against said
post members to diminish flow through said bores;
said snap disc being flexed back to its first position when the
water temperature drops by a sufficient amount, whereupon full flow
through said bores can resume.
9. A flow valve as defined in claim 8 wherein said snap disc is
circular and wherein said post members and hence said bores are
arranged in a circular pattern.
10. A flow valve as defined in claim 9 wherein the diameter of said
snap disc exceeds the diameter of said circular arrangement of post
members whereby said peripheral margin abuts against the outermost
edge of said post members.
11. A flow valve as defined in claim 8 wherein said plate member is
circular and wherein the diameter of said plate member exceeds that
of said snap disc to permit water flow around the exterior edge of
said snap disc in either snap disc position.
12. A flow valve as defined in claim 11 wherein said means
connecting said center of said snap disc with said first surface of
said plate member includes a central projection extending in an
upstream direction from the center of said plate member and a
fastener projecting through an aperture in the center of said snap
disc.
13. An improved shower head comprising:
a body means having an inlet end adapted to be connected to a water
supply and having an opposed discharge end;
said body means having an internal chamber into which water flows
from said inlet end;
said body means having a shaped opening at the discharge end
thereof;
a water spreader disposed within said shaped opening to spread the
water outwardly and along the walls defining said shaped opening,
so the water discharges from said body means as a spray;
a plate member extending across said internal chamber;
said plate member having a plurality of flow ports
therethrough;
a thermosensitive snap disc centrally connected with said plate
member on the side thereof closest to said inlet end;
said snap disc having at least its peripheral margin portion
flexurally movable between a first position flexed away from said
plate member and a second position flexed toward said plate
member;
said snap disc peripheral margin portion normally being disposed in
said first position whereby water from said inlet flows into said
internal chamber, around said snap disc, through said flow ports,
to impinge upon said water spreader and discharge as a spray;
said snap disc peripheral margin portion being displaced to said
second position when the temperature of said water exceeds a
predetermined magnitude, said peripheral margin portion in said
second position partially blocking said flow ports whereby the
quantity of water passing through said flow ports and impinging
upon said water spreader is materially reduced, so the water
discharges from said body means as a dribble;
said snap disc peripheral margin portion being returned to said
first position when the water temperature in said internal chamber
is reduced to a preselected value whereupon the water will again
discharge from said body means as a spray.
14. An improved shower head as defined in claim 13 wherein said
plate member includes a plurality of post members extending toward
said inlet end and wherein said flow ports are bores passing
through said post members and said plate member, said snap disc
peripheral margin portion abutting atainst said post members when
said peripheral margin is displaced to said second position.
15. An improved shower head as defined in claim 13 wherein said
snap disc is fabricated of a bimetallic alloy.
Description
This invention relates to a thermosensitive flow control device and
in particular it relates to a flow control device which retards or
diminishes flow of a liquid stream when the stream temperature
exceeds a predetermined first temperature and which restores full
flow when the stream temperature drops to or below a predetermined
second and lower temperature.
The present invention finds particular utility when used in
connection with a water distribution system wherein a mix of cold
water and heated water is delivered and dispensed through a spray
head, such as a shower head. A serious problem exists if the water
temperature of a shower spray should, for any reason, exceed the
scalding temperature. In such an event, the occupant of the shower
might receive a burn from the scalding water, or at the least, will
experience serious discomfort. Moreover, there is the potential
hazard which could occur if the shower occupant falls and injures
himself while trying to avoid a flow of excessively hot water. In
institutions, such as hospitals, there is the possibility that a
shower occupant could experience cardiac problems due to the shock
of excessively hot water from a shower.
There are various ways in which the water temperature in a water
distribution system, such as a shower, might suddenly change from a
proper temperature to an excessively hot or scalding temperature.
In institutional facilities such as hospitals or in buildings such
as hotels, motels and the like, it is a common practise to use a
piping arrangement wherein several different rooms are connected to
the same flow lines. Thus, it is not an uncommon occurrence for the
water temperature in a shower being operated in one room to sharply
increase, in a sudden manner, when a toilet is flushed in an
adjoining room or when cold water is turned on in the sink or
shower of an adjoining room. In such event, the occupant standing
in the shower might suddenly and unexpectedly be subjected to a
sudden water temperature change wherein the shower spray suddenly
becomes excessively hot or scalding.
There are other situations in which the water temperature in a
shower might suddenly increase, thus causing a danger to the
occupant of the shower. There is the possibility that the occupant
of a shower might inadvertently bump against the water control
knobs and turn off the cold water supply. This is particularly true
in instances where a single lever control is used with the position
of the lever determining the water temperature. Another possibility
for sudden change in water temperature could be through mere
horseplay of children in their own shower or in a camp shower,
through mischief of students in dormitories, and the like.
There have in the past been certain proposals for preventing injury
in the event of a sudden water temperature increase in a water
distribution system for showers or the like, but these proposals
have not been altogether satisfactory or practical. For example, it
has been proposed to attach a shield or deflector to a shower head
so that if the water temperature at the shower head becomes
excessive, the shield will swing across the front of the shower to
interrupt the spray from the shower head. An arrangement of this
type would present an unsightly and unattractive appearance for the
shower head, and additionally, would require various swinging arms
and moving members to be exposed where they might possibly be bent
or otherwise misaligned so that the deflector might not operate
properly when needed. Another proposal has been to provide a
thermostatically controlled valve in the shower system to close off
all flow through the shower head when the water temperature becomes
excessively hot. However, in such an arrangement, it then becomes
necessary to entirely shut off both the hot and the cold water in
order to let the valve reset and to then start the shower again
with the water properly adjusted. Naturally, an arrangement of this
type would be undesirable since, in the event the shower is being
used in a motel or like institution, the occupant of the shower
might have to turn the water on and off two or three times in order
to complete a single bathing in the shower.
Under these circumstances, it is an object of the present invention
to provide a temperature sensitive arrangement for use in a water
distribution system, such as a shower, wherein the water flow will
be diminished or retarded in the event that the temperature thereof
becomes too hot, and wherein the water flow will automatically
resume once the water temperature returns to its preset
conditions.
Another object of the present invention is to provide an improved
form of flow valve which can advantageously be used in a water
distribution system such as a shower to prevent scalding of the
occupant of the shower in the event that the water temperature
should suddenly increase, but which does not require any resetting
or other manual control by the occupant of the shower.
Another object of the present invention is to provide an anti-scald
spray head, particularly useful for showers to prevent the occupant
of the shower from becoming scalded or otherwise injured through a
sudden temperature increase in the shower water.
Further objects of the present invention include the provision of a
flow control device to temporarily interrupt the flow of water in a
water distribution system until the temperature thereof drops below
a predetermined level, which device is simple yet efficient in
operation, which is corrosion resistant and which does not clog or
otherwise interfere with the flow of water in the system, which is
quiet in operation, which responds quickly to changes in water
temperature, which is relatively inexpensive to produce and
install, and which can be installed in existing plumbing
configurations and fixtures without the need for breaking out
walls, changing piping arrangements, or the like.
Other objects, advantages and salient features of the present
invention will become apparent from the following detailed
description which, taken in conjunction with the annexed drawings,
discloses a preferred embodiment thereof.
The foregoing objects are attained generally by providing a flow
control device which includes a bimetallic snap disc mounted in
juxtaposition to a plate member having a series of flow ports
therein. The snap disc and the plate member can be advantageously
mounted within a spray head, such as a shower head, with the snap
disc being oriented in the upstream direction. Ordinarily, the snap
disc is flexed away from the port means in the plate member so that
the flow of water through the spray head will traverse around the
snap disc and through the port means and will discharge from the
head in the form of a spray. However, when the water temperature
reaches a predetermined magnitude, the snap disc automatically and
rapidly flexes in the opposite direction and toward the port means
to retard and diminish, but not eliminate the water flow through
the port means. The water flow from the shower head will at this
point be reduced to a dribble which would not ordinarily contact
against the body of an occupant of the shower. The excessively hot
water can continue to dribble from the shower head until the
temperature of the water reaching the snap disc drops to a
predetermined second and lower temperature, whereupon the snap disc
will automatically flex away from the port means and the water will
once again discharge from the shower head as a spray.
Referring now to the drawings, which form a part of this original
disclosure:
FIG. 1 is a longitudinal sectional view of a spray head
incorporating a thermosensitive flow control device in accordance
with the principles of the present invention, with such flow
control device being in its normal open position to permit the
water to discharge from the head in the form of a spray;
FIG. 2 is a longitudinal sectional view, similar to FIG. 1, but
with the thermosensitive flow control device being positioned to
retard and diminish flow because the water temperature being
delivered through the head is excessive, and in the arrangement
shown in FIG. 2, the water is discharged from the head in the form
of a dribble;
FIG. 3 is an exploded perspective view showing the details of the
flow control device or valve;
FIG. 4 is an enlarged fragmentary sectional view showing the manner
in which the flow is diminished or retarded when the parts are in
the position of FIG. 2;
FIG. 5 is a diagrammatic view showing the manner in which the water
discharges in the form of a spray when the flow control device is
in the configuration shown in FIG. 1; and
FIG. 6 is a diagrammatic view showing the manner in which the water
discharges as a dribble when the flow control device is in the
position shown in FIG. 2.
Since the device of the present invention finds particular utility
when used in connection with a shower head, the following detailed
description will be directed to a shower head with a
thermosensitive flow control device therein. It will, however, be
understood that the principles of the present invention are by no
means limited to the control of water flow through a shower head,
and indeed, the liquid stream controlled by the flow control device
need not even be water and the flow head need not be a shower head.
The terms "thermosensitive" and "temperature responsive" and
"thermally responsive" may be used interchangeably hereinafter for
the purpose of indicating that the flow control device of the
present invention operates in response to changes in temperature of
the liquid stream passing across the flow control device.
Referring now to the present invention in further detail, attention
is directed to FIGS. 1 and 2 wherein there is disclosed a flow head
or spray head generally designated 10 having therein a
thermosensitive flow control device generally designated 12. The
flow head 10 is, as aforementioned, advantageously a shower head,
but it can also be a faucet, a sprinkler head or the like. As such,
the flow head 10 includes a body means generally designated 14
which is adapted to be connected to a liquid stream, such as a
water supply, by means of a connector generally designated 16.
The body means 14 includes a first body member 18 having an inlet
end with an opening or socket 20 formed therein and a threaded neck
22 forming a projection. The connector 16 includes a ball head 24
adapted to fit within the socket 20 and to abut against a washer 26
therein. A collar 28 is threaded on to the neck 22 of the body
portion 18 and the collar includes an inwardly directed flange 30
which abuts against the ball 24 to maintain the same in the socket
20. In this manner, the body means is mounted to and universally
movable with respect to the ball head 24. The connector 16 also
includes an extending tubular portion 32 which projects beyond the
ball head 24 and beyond the collar 28 for attachment to a water
supply pipe by means of internal screw threads 34.
The body member 18 includes a second or forward portion 36 which is
provided with a shaped discharge opening defined by curved walls 38
which provide the opening with a generally frusto-hemispherical or
frusto-ogival configuration.
The body portion 18 has at its forward end, a reduced diameter
externally threaded neck 40 which terminates in a flat forward
surface 42. The body portion 36 is provided at its rear end with a
flat internal shoulder 44 and with an internally threaded
projecting portion 46 extending beyond the shoulder to thread on to
the neck 40 of the body portion 18. The thermosensitive flow
control device 12 is clamped between the surfaces 42 and 44 in a
manner to be described herinafter.
In order to provide the flow head 10 with an attractive and
streamlined appearance, the external surfaces of the collar 28, the
body portion 18 and at least a part of the body portion 36 are
formed so that such surfaces are generally coincident, having an
outwardly and forwardly tapering relationship to provide the head
10 with a generally frusto-conical configuration.
A central bore or flow passage 48 extends through the connector 16
to permit water to be introduced into the interior of the flow head
10 through its inlet end. It will, of course, be understood that
the piping system by which the water is delivered contains a cold
water pipe and a hot water pipe, each of which is provided with a
flow control valve which can be manually operated to adjust the
temperature of the water. The cold water and the hot water are
mixied together and are delivered through a common pipe to the
connector 16 and hence into the flow head 10. An internal chamber
50 is provided in the body means 14 with such chamber being defined
and circumscribed by a frusto-conical wall portion 52 which
enlarges forwardly from the inlet end and which merges into a
cylindrical wall portion 54. The body portion 36 includes a
continuing cylindrical sidewall portion 56, which can be coincident
with the sidewall portion 54 in the body portion 18, and the
internal chamber 50 terminates in a forward wall 58. A series of
flow passages 60 extend longitudinally forward from the wall 58 to
provide flow passages for the water to discharge from the internal
chamber 50 to the discharge opening 38. A series of shaped grooves
or vanes 62 are formed along the walls of the opening 38 to cause
the water to be discharged in a series of separate streams. A water
spreader 64 is centrally positioned within the shaped discharge
opening 38 and is connected to the central portion between the flow
passages 60 by means of an elongated threaded stud 66. The water
spreader 64 includes a flat surface 68 positioned immediately
adjacent the separate flow passages 60 so that the water
discharging from such flow passages impinges upon the surface 68
and is spread outwardly to pass along the shaped grooves or vanes
62 in the walls of the shaped surface 38 and to discharge forwardly
therefrom in the form of a spray. Adjustment of the water spreader
64 can move the surface 68 toward or away from the flow passages 60
to cause a concomitant adjustment in the flow characteristics of
the spray.
That portion of the spray head thus far described can be considered
generally conventional and does not form any part of the present
invention, except as an environment into which the thermosensitive
flow control device 12 can be installed and attached. For a
consideration of the details of the thermosensitive flow control
device 12, attention is directed to FIG. 3 wherein it can be seen
that the flow control device 12 includes a plate member 70 having a
first surface 72 intended to be disposed in an upstream direction
and an opposed and parallel second surface 74 intended to be
disposed in a downstream direction. The plate member 70 is provided
with a series of forwardly extending post members 76, each of which
is perpendicular to the plate surfaces 72 and 74. The post members
76 are arranged in a generally circular pattern, and although eight
such post members are shown in FIG. 3, the number of such post
members is not considered critical so long as a plurality of post
members are provided. The circular series of post members are set
inwardly a sufficient distance from the marginal edge of the plate
member 70 to permit such marginal edge to be clamped between the
flat surface 42 of the body portion 18 and the flat shoulder 44 of
the body portion 36, as shown in FIGS. 1 and 2. Naturally, a
suitable sealing medium, such as one or more O-rings, can be
utilized to prevent any water leakage from occurring around the
plate member 70. Also, the posst members 76 are set inwardly a
sufficient distance from the side walls 54 and 56 which form the
sides at the forward portion of the internal chamber 50 in the body
means.
A bore 78 extends through each of the post members 76 and through
the plate member 70, as best illustrated in FIGS. 1 and 2. As a
result, it can be seen that eight separate bores 78 are provided
and the water passing through the internal chamber 50 of the body
means must pass through these eight separate bores and then through
the flow passages 60 to discharge from the body means at the
forward or dispensing end thereof.
The plate member 70 also includes a central projection 80 having a
threaded aperture 82 formed therein. A threaded bolt 86 is provided
for the purpose of attaching a thermosensitive bimetallic snap disc
88 to the plate member by passing through an aperture 90 in the
snap disc and threading into the threaded bore 82 in the projection
80. The snap disc 88 has a slightly dished configuration, making it
slightly convex on one side and slightly concave on the other. The
disc can be formed of any suitable bimetallic alloy and the disc is
adapted to snap or flex over center when the temperature reaches a
particular predetermined magnitude. Thus, if the disc ordinarily
has a convex configuration, it will when subjected to temperature
of a predetermined magnitude snap over center to achieve a concave
configuration. Stated another way, if the disc is ordinarily dished
forwardly, it will, when subject to temperature of a predetermined
magnitude, snap over center to be dished rearwardly. The diameter
of the thermosensitive snap disc 88 is somewhat greater than the
diameter of the circle formed by the post members 76, but is
somewhat less than the diameter of the plate member 70 or of the
internal diameter defined by the walls 54 of the internal
chamber.
While the temperatures at which the disc 88 operates or snaps can
be varied as desires, through a control of the material from which
the disc is fabricated, the thickness of the disc and like
engineering parametere an advantageous disc construction for a
shower is one which will snap over when the temperature reaches
130.degree.F and which will snap back when the temperature of the
surrounding water drops to 120.degree.F.
Referring again to FIG. 1, the disc 88 is shown in its normal
position where it is dished toward the inlet end of the body means
and away from the discharge end thereof. Stated another way, in
FIG. 1, the snap disc 88 is concave on its upstream side and convex
on its downstream side. In such an arrangement, the water will
enter through the flow passage 48 into the internal chamber 50,
will flow around the disc 88, through the bores or flow ports 78
through the flow passages 60 and will discharge along grooves or
vanes 62 along the dispensing wall 38 in the form of a spray, as
designated S in FIG. 5. So long as the water temperature remains
below the preselected value, which, as aforementioned, can
advantageously be 130.degree.F, the snap disc 88 will remain in the
orientation shown in FIG. 1 and the water will be discharged in the
form of the spray S. However, as soon as the water temperature
exceeds the maximum predetermined magnitude, which as
aforementioned can be 130.degree.F, the disc 88 will snap over from
its position of FIG. 1 to its position of FIG. 2. In such position,
the disc is dished away from the inlet end and toward the outlet
end of the flow head. Stated another way, the disc is convex on its
upstream side and concave on its downstream side. The entire disc
88 need not be uniformly dished, and instead, it can be formed in
the nature of a cymbal where the peripheral margin portion is
somewhat flatter than the central portion.
Even though the central portion of the disc 88 is retained by
mounting the same against the projection 80 from the plate member,
such a mounting arrangement will not prevent the disc from snapping
from its position of FIG. 1 to its position of FIG. 2. In any
event, it will be apparent that at least the peripheral margin
portion of the disc is free for flexural movement between its FIG.
1 position and its FIG. 2 position. Moreover, when the disc 88
snaps over from its FIG. 1 position to its FIG. 2 position, it
abuts against the post members 76. This can be most clearly seen
from the enlarged illustration in FIG. 4 wherein the post member 76
is shown as having a flat forward surface 92 which is parallel to
the surfaces 72 and 74 of the plate member 70. The peripheral
margin portion of the snap disc 88 is designated 94 and at some
point along the underside of this peripheral margin portion, the
disc member 88 will contact and abut against the sharp corner
formed by the intersection of the side walls of the post members 76
and the forward walls 92 thereof. When this occurs, it will be
apparent that the disc member partially but not entirely covers the
flow ports formed by the posts 76 and their bores 78. Flow of water
through the device will thus be retarded or diminished or impeded.
This occurs because the water is no longer free to flow directly
through the open bores 78, but instead, must flow between the post
members, around the edges of the snap disc 88 and between the
underside of the peripheral margin portion 94 of the snap disc and
the forward wall 92 of the post members. Because of this partial
blocking of the individual flow ports through the post member 76,
the quantity of water discharging from the flow head will be
diminished and the water will no longer discharge as a spray, but
instead, will discharge in the form of a dribble as shown in FIG. 6
where it is designated D.
It is important to note that in its FIG. 2 position, the snap disc
does not eliminate or totally block the water flow through the
spray head, and there are two reasons for this. First, if the flow
were entirely blocked, the hot water would be unable to discharge
from the head. It is often the case that the excessively hot or
scalding water is a mere slug of water which passes in a few
seconds, and accordingly, this slug of hot water is able to
discharge from the spray head in the form of a dribble D which
should not contact the occupant of the shower. Second, and of equal
importance, if the snap disc were to completely block flow through
the device, then the buildup of the water pressure on the upstream
side of the snap disc could be great enough to cause an excessive
buildup of pressure in the upstream piping of the shower system.
This excessive pressure could cause leaks in the shower wall. Also,
completely closing the shower head rapidly could cause severe water
hammer problems that could lead to broken pipes and mounts.
Therefore, by using the arrangement described herein wherein the
water flow is diminished but not stopped, the water pressure on
opposed sides of the snap disc 88 will remain about the same and
the disc will be able to snap back to its original position of FIG.
1 after the water temperature has dropped by a predetermined amount
to a second and lower temperature which, as aforementioned, can
advantageously be 120.degree.F.
The occupant of the shower is shown in phantom lines in FIGS. 5 and
6 and is designated O. Ordinarily, this occupant is standing in the
shower in a position where the spray S will contact against his or
her body for bathing purposes. If for any reason the temperature of
the water discharging from the flow head 10 should suddenly rise
above the predetermined maximum of 130.degree.F or whatever other
maximum temperature is selected, the disc 88 will snap or flex from
its position shown in FIG. 1 to its position of FIG. 2 in a rapid
manner. Once the disc 88 reaches the position of FIG. 2, the water
discharging from the flow head 10 will change to the dribble D as
shown in FIG. 6 which will not contact the occupant and which will
not cause any injury to him or her. This excessively hot water will
continue to discharge from the flow head in the form of the dribble
D until the water temperature within the internal chamber 50
surrounding the snap disc 88 drops to a second and lower
temperature, which can be the 120.degree.F previously mentioned, or
whatever other low end temperature is selected. At that point in
time, the disc 88 will rapidly snap back from its FIG. 2 position
to its FIG. 1 position and the water will then discharge once again
in the form of spray S. Thus, the occupant of the shower need not
touch or adjust any of the temperature controls for the shower nor
need he do anything except wait for a few moments until the
excessively hot water discharges from the flow head in the form of
the dribble D.
While one advantageous form of the present invention has been
described herein, it will be apparent to those of ordinary skill in
the art that various changes and modifications may be made, and
that the invention may be adapted for other purposes, without
departing from the spirit and scope of the inventive concept as set
forth in the appended claims.
* * * * *