U.S. patent application number 09/567510 was filed with the patent office on 2001-10-04 for apparatus for flow detection, measurement and control and method for use of same in a fire sprinkler system.
Invention is credited to Young, Richard.
Application Number | 20010026225 09/567510 |
Document ID | / |
Family ID | 44484843 |
Filed Date | 2001-10-04 |
United States Patent
Application |
20010026225 |
Kind Code |
A1 |
Young, Richard |
October 4, 2001 |
Apparatus for flow detection, measurement and control and method
for use of same in a fire sprinkler system
Abstract
An apparatus for flow detection, measurement and control and
method for use of same in a piping and/or fire sprinkler system.
The apparatus combines a flow sensor for creating an electrical
output proportional to flow through therethrough with a bypass
means for allowing flow through an alternate flow path where a
primary flow path is insufficient to supply the demand. The
apparatus includes a moving orifice plate, which is displaced by
flow through the sensor and creates an electronic output by the
interaction of a moving magnet moving in tandem with the orifice
plate with a normally closed Reed switch on an exterior surface of
the sensor, which is opened when the magnet is displaced into
sufficiently close proximity to the Reed switch. The apparatus can
also be adapted to serve as a double check valve. A moving check is
added with a sealing means thereon for providing one check, and
sealing means on the orifice plate are provided to serve as a
second check. A method of using said apparatus in a piping and/or
fire protection system is disclosed. The method allows a bypass of
flow restrictions such as a water softener. The method also
provides for re-circulation of heated water through a fire
protection system to prevent stagnation and freezing of water in
the system. The method can be used with a multipurpose piping
system having both fire sprinklers and domestic uses supplied
thereby.
Inventors: |
Young, Richard; (Edmond,
OK) |
Correspondence
Address: |
Edward L White P C
50 Penn Place 4th Floor
1900 N W Expressway
Oklahoma City
OK
73118-1803
US
|
Family ID: |
44484843 |
Appl. No.: |
09/567510 |
Filed: |
May 8, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09567510 |
May 8, 2000 |
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09483999 |
Jan 18, 2000 |
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6239708 |
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09483999 |
Jan 18, 2000 |
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09098976 |
Jun 17, 1998 |
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6081196 |
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Current U.S.
Class: |
340/606 ;
340/609; 340/611 |
Current CPC
Class: |
G01M 3/2815 20130101;
G08B 17/04 20130101; G08B 21/18 20130101; G01F 1/363 20130101; G01F
1/42 20130101; G01F 1/38 20130101 |
Class at
Publication: |
340/606 ;
340/609; 340/611 |
International
Class: |
G08B 021/00 |
Claims
What I claim is:
1. A piping system comprising: a. a water supply; b. a means for
heating water; c. common piping means for receiving water from the
supply and delivering it to at least one use; d. pipe circulation
means for circulating water through the common piping back to the
heating means to maintain a minimum specified temperature in the
common piping, whereby the danger of freezing water in the piping
is eliminated.
2. The piping system of claim 1, for use as a fire protection
system having at least one fire protection sprinkler supplied by
the common piping.
3. The piping system of claim 2 supplying, in addition, at least
one non-fire protection use.
4. The system of claim 3, where a bypass means for diverting water
around the heating means is provided for situations where water
demands exceed the flow capacity of the heating means.
5. The system of claim 4, where the bypass means is a flow sensor
comprising: a. an annular housing to be installed in the flow path
of the common piping; b. a moving orifice plate defining an opening
therein; c. a magnet adapted to a abut the face of the orifice
plate and move in cooperation therewith; d. a biasing means for
urging the moving orifice plate away from an outlet end of the
annular housing; e. at least one Reed switch disposed on a outer
surface of the annular housing for creating an electronic signal
related to the position of the magnet within the annular housing,
the Reed switch being attached so as to be easily movable in
relation to the annular housing, whereby, as fluid flows to the
annular housing the orifice plate is urged towards the outlet end
of the annular housing causing a change in the electronic signal
created by the Reed switch; and f. a bullet rod axially disposed
within the annular housing so as to be closely received within the
orifice plate opening, blocking flow through the opening until a
specified differential pressure is reached when the orifice plate
is displaced past the bullet rod allowing flow through the
opening.
6. The system of claim 5, where two Reed switches are incorporated
on the annular housing, first a Reed switch for enunciating a
trouble alarm, and a second Reed switch for enunciating a fire
alarm.
7. The system of claim 6, where a third Reed switch is incorporated
on the housing for closing a valve, preventing flow to a lawn
sprinkler system.
8. The system of claim 4, where the bypass means comprises: a. a
flow sensor; b. a normally closed valve; and c. a controller in
communication with the flow sensor and controlling the position of
the valve for opening the valve when the demand for water exceeds
the capacity of a flow impediment so as to bypass the flow
impediment.
9. The system of claim 3, incorporating a device between the
heating means and the water supply and further including a bypass
means for diverting water around the device when the demand for
water exceeds the flow capacity of the device.
10. The system of claim 9, further including a second bypass means
for diverting water around the heating means when the demand for
water exceeds the flow capacity of the heating means.
11. The system of claim 3, where a circulation means comprises a
pump controlled by a controller in communication with a temperature
measurement means for determining when the temperature of water in
the piping drops below the minimum specified temperature, the
controller engaging the pump which re-circulates the water in a
piping through the heating means to maintain the minimum specified
temperature.
12. The system of claim 9, where a circulation means comprises a
pump controlled by a controller in communication with a temperature
measurement means for determining when the temperature of water in
the piping drops below the minimum specified temperature, the
controller engaging the pump which re-circulates the water in a
piping through the heating means to maintain the minimum specified
temperature.
13. The system of claim 3, where at least one domestic use is also
supplied with hot water by the common piping.
14. The system of claim 9, where at least one domestic use is also
supplied with hot water by the common piping.
15. The system of claim 3, where a short circuit means is provided
for suppling more water to the common piping near the circulation
means where water demands exceed the capacity of the common
piping.
16. The system of claim 9, where a short circuit means is provided
for suppling more water to the common piping near the circulation
means where water demands exceed the capacity of the common
piping.
17. The system of claim 15, where the short circuit means
comprises: a. an annular housing to be installed in the flow path;
b. a moving orifice plate defining an opening therein; c. a biasing
means for urging the moving orifice plate away from an outlet into
the annular housing; d. a bullet rod actually disposed within the
annular housing so as to be received within the orifice plate
opening, blocking flow through the opening until a specified
differential pressure is reached when the orifice plate is
displaced past the bullet rod allowing flow through the
opening.
18. The system of claim 16, where the short circuit means
comprises: a. an annular housing to be installed in the flow path;
b. a moving orifice plate defining an opening therein; c. a biasing
means for urging the moving orifice plate away from an outlet into
the annular housing; d. a bullet rod actually disposed within the
annular housing so as to be received within the orifice plate
opening, blocking flow through the opening until a specified
differential pressure is reached when the orifice plate is
displaced past the bullet rod allowing flow through the
opening.
19. A system for providing circulation of water in piping supplying
fire protection sprinklers, the system comprising: a. common piping
carrying water, which was is caused to flow at periodic intervals;
b. a head fitting receiving a fire protection sprinkler therein and
further defining a chamber therein in communication with the
sprinklers; c. supply and return lines for supplying water to and
returning water from the head fitting, the lines being in
communication with the common piping; and d. a pump means for using
the velocity head created by the water flowing through the common
piping to pump water to the head fitting causing circulation there
through as a result of flow in the common piping.
20. The system of claim 3, each fire protection sprinkler
including: a. a head fitting receiving a fire protection sprinkler
therein and further defining a chamber therein in communication
with the sprinkler via a reverse-J fitting to insulate the
sprinkler head from hot water supplied to the head fitting; b.
supply and return lines for supplying water to and returning water
from the head fitting, the lines being in communication with the
common piping; c. a pump means for using the velocity head created
by the water flowing through the common piping to pump water to the
head fitting causing circulation there through as a result of flow
in the common piping.
21. The system of claim 3 further comprising: a. a normally closed
actuated valve disposed between the bypass means and the heating
means; and b. a controller for controlling the valve such that in a
first state, the valve is opened in repose to a water demand from
the common piping and in a second state, the actuated valve remains
closed, and an alarm signal is sent to the controller in response
to a significant water demand from the common piping, whereby, when
a structure is unoccupied and the controller is in the second
state, an alarm condition is created when a water demand beyond
minimal domestic uses is detected.
22. The system of claim 3 further comprising: a. a normally closed
actuated valve disposed between the bypass means and the water
softener; and b. a controller for controlling the valve such that
in a first state, the valve is opened in repose to a water demand
from the common piping and in a second state, the actuated valve
remains closed, and an alarm signal is sent to the controller in
response to a significant water demand from the common piping,
whereby, when a structure is unoccupied and the controller is in
the second state, an alarm condition is created when a water demand
beyond minimal domestic uses is detected.
23. The system of claim 8, where three alarm levels are provided: a
first level which opens the valve; a second level which sounds a
trouble alarm; and a third level which enunciates a fire alarm.
24. An apparatus for use as a flow sensor comprising: a. an annular
housing to be installed in the flow path of a fluid, the annular
housing defining a chamber therein which has a fixed interior
diameter in at least one section and a main inlet and outlet; b. a
moving orifice plate defining an opening therein where the orifice
plate has an outer diameter which is smaller than the diameter of
the fixed section of the annular housing, but is sized so as to
allow minimal flow of water around its edges and between the
diameter of the annular housing; c. a magnet adapted to abut and
move with the orifice plate; d. a biasing means for urging the
moving orifice plate and magnet away from the outlet; and e. at
least one Reed switch disposed on an outer surface of the annular
housing for creating an electronic signal related to the position
of the orifice plate magnet within the annular housing, the Reed
switch being attached so as to be easily movable in relation to and
annular housing, whereby as fluid flows through the annular housing
the orifice plate is urged towards to outlet end of the annular
housing causing a change in the electronic signal created by the
Reed switch.
25. The apparatus of claim 24 further including a bullet rod
axially disposed within the annular housing so as to be received
within the orifice plate opening, blocking flow through the opening
until a specified differential pressure is reached when the orifice
plate is displaced past the bullet rod allowing flow through the
opening.
26. The apparatus of claim 24 further including a device outlet
port on the inlet side of the moving orifice plate for delivering
water to an external device and a device inlet port on the outlet
side of the moving orifice plate for returning water from the
device, whereby the apparatus serves as a bypass mechanism which
typically diverts flow through the external device, but allows
bypass flow through the moving orifice plate when flow demand
exceeds a flow capacity of the external device.
27. The apparatus of claim 24 further comprising: 1. the bullet rod
further defining a bullet cylinder therein; 2. the inlet port
defining a check shoulder seat; 3. a moving check having a check
piston slidingly received in the cylinder, a leading edge bearing a
first seal means for sealing engagement with the check shoulder
seat, and a piston end; 4. a biasing means disposed in the bullet
cylinder for biasing the moving check toward the inlet port; 5.
second seal means disposed on the moving orifice plate for sealing
engagement with the bullet port, whereby, when fluid flows
therethrough from the inlet to the outlet, the moving check is
biased away from the inlet port allowing flow through the
apparatus, and moving orifice plate in proportion to the flow rate,
but fluid flow is prevented from flowing from the outlet to the
inlet by a first seal formed between the first seal means and the
bullet port and a second seal formed between the second seal means
and the check shoulder seat preventing flow in the undesired
direction.
28. The apparatus of claim 27 where the first and second seal means
are o-rings adapted to engage sealing surfaces.
29. The apparatus of claim 27 where the magnet and the orifice are
combined into a single piece.
30. The apparatus of claim 27 where the combined orifice
plate/magnet is coated with a material for allowing it to form a
seal directly with the bullet port.
31. The apparatus of claim 4 further comprising: a. a main control
valve disposed on the supply side of the bypass means with a Reid
switch on the valve for sending an alarm signal if the valve is
closed; b. the bypass means having, i. a flow sensor means for
measuring the flow therethrough and creating a first output when
the measured flow exceeds capacity of the heating means, a second
trouble alarm output and a third fire alarm output, ii. an actuated
valve providing an alternate flow path when opened, and iii. a
controller for receiving a signal from the main control valve and
enunciating an alarm if it is close, and for receiving a signal
from the flow sensor and for sending a signal to open the valve
when flow demand exceeds the capacity of the heating means,
enunciating a trouble alarm when the flow exceeds a second level,
and enunciating a fire alarm when the flow exceeds a third
level.
32. The apparatus of claim 9 further comprising: a. a main control
valve disposed on the supply side of the bypass means with a Reed
switch on the valve for sending an alarm signal if the valve is
closed; b. the bypass means having, i. a flow sensor means for
measuring the flow therethrough and creating a first output when
the measured flow exceeds capacity of the water softener, a second
trouble alarm output and a third fire alarm output, ii. an actuated
valve providing an alternate flow path when opened, and iii. a
controller for receiving a signal from the main control valve and
enunciating an alarm if it is close, and for receiving a signal
from the flow sensor and for sending a signal to open the valve
when flow demand exceeds the capacity of the heating means,
enunciating a trouble alarm when the flow exceeds a second level,
and enunciating a fire alarm when the flow exceeds a third level.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of Ser. No.
09/483,999 filed Jan. 18, 2000, which was a continuation-in-part of
Ser. No. 09/098,976 filed Jun. 1, 1998 (hereinafter collectively
referred to as the "Parent Applications").
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to the fields of flow detection,
measurement and control. The invention also relates to fire
suppression systems. In particular, the invention relates to
multi-purpose piping systems for fire protection in structures and
flow elements related thereto. The invention relates to systems for
ensuring adequate circulation to fire protection sprinklers to
minimize stagnation and/or freezing.
[0004] 2. Description of the Prior Art
[0005] Practically any system where fluid flows in a conduit can
use flow measurement devices. There are any many different kinds of
flow measurement devices as there are systems where fluids flow in
a conduit (such as a typical pipe). For example, it is well known
that there is a pressure drop across an orifice plate, and that
this pressure drop can be used to determine the fluid flow through
the pipe. The pressure drop is proportional to the velocity of the
fluid in the pipe. As another example, a positive displacement
device may be placed in a conduit, which directly measures the
volume of fluid flowing therethrough. From the known volume
measured by the positive displacement device, the velocity of the
fluid in the pipe can be determined. An example of this type device
is a paddle flow switch commonly used in fire protection systems.
Each type of flow measurement device has its strengths and
weaknesses, and may be applicable to one system, while not being
suitable for another.
[0006] Check valves (single and double acting) are also widely used
in systems where fluids flow in conduits. The purpose of a check
valve is to allow flow in one desired direction, but prevent flow
in the opposite undesired direction. Existing check valves often
use a moving seat, which is forced open by fluid flowing in the
desired direction, but which moving seat is sealingly forced
against an annular shoulder, preventing flow in the undesired,
opposite direction.
[0007] It is well known to use electronic sensor means to transmit
a signal generated by a flow measurement device to a read out or
alarm means. The electronic output may be generated in response to
a pressure transducer or the like. There are a myriad of ways to
generate an electronic signal proportional to flow of a fluid in a
conduit. As with our orifice plate noted above, the differential
pressure is proportional to the flow in the conduit. Therefore, a
differential pressure transducer exposed to the up stream and down
stream fluids would produce an output electrical signal
proportional to the flow of fluid through the conduit. In the
paddle flow switch, the volume between the paddles is known, and a
signal is generated indicating the number of revolutions per unit
time of the paddle, thus allowing calculation of the flow velocity.
Vane-type paddle flow switches are typically used in the fire
protection industry.
[0008] It is also well known to provide a bypass means for allowing
fluid flow around a restriction, in certain circumstances. For
example, for use in a multi-purpose piping system, it made be
desirable to divert flow around a water softener where the demand
for water in the residence for fire protection is greater than is
able to flow through the water softener. As another example, in a
chemical process, chemicals may be passed through a reactor unit.
However, should the reactor become plugged or otherwise unduly
restrict the flow, it may be desirable to bypass the reactor so as
to prevent damage to the reactor vessel and/or a process upset. In
these circumstances, it is necessary to have a bypass means which
can divert flow around the flow element causing the pressure drop
in certain circumstances.
[0009] In most fluid flow systems, each of the above noted flow
elements (flow measurement, check valve, bypass means) is a
separate fitting which must be placed in the fluid system. It is
often desirable to combine as many of the above noted functions
into one device as possible. The combination of multiple devices,
for example the flow meter, check valve, and means for converting a
fluid flow to an electronic out put signal, are obvious. A reduced
number of devices reduces complexity, cost, and difficulty of
installation of a fluid flow system.
[0010] It is also well known to provide a means for enunciating an
alarm when water flows through a fire protection system. Typical
commercial fire protection systems do not have significant water
flow therethrough unless a sprinkler head is activated by a fire.
Thus, the typical commercial system need only to detect whether or
not flow is present, and if so, an alarm must be enunciated.
[0011] In application Ser. No. 09/098,976 filed on Jun. 1, 1998,
for an Apparatus And Method For Multi-purpose Residential Water
Flow Fire Alarm, a method was disclosed which allows the same
piping to be used for both domestic and fire protection needs. The
method provided for a flow detection and measurement means which is
capable of distinguishing typical domestic flow from fire
protection flow caused by the operation of one or more sprinkler
heads.
[0012] The National Fire Protection Association ("NFPA") has
established standards for the design and operation of multi-purpose
residential fire sprinkler systems. The standard is known as NFPA
13D, 1999 Ed. It defines a multi-purpose piping system ("MPS") as
"[a] piping system within dwellings and manufactured homes intended
to serve both domestic and fire protection needs."
[0013] Typical commercial fire sprinkler systems utilize a water
flow detector to provide an alarm means. When a flow of sufficient,
minimal, volume is detected, typical commercial systems indicate an
alarm condition. The only reason that water typically flows in
commercial systems is activation of a sprinkler head. Therefore, in
a typical commercial system an alarm means need only determine
whether or not water is flowing. Paddle flow switches are commonly
used to determine when flow occurs in commercial systems. As noted
above, these are typically vane-type paddle flow switches.
[0014] In the MPS water regularly flows through the common piping.
Flows occur to supply domestic needs within the residence. Whenever
a sink, shower or toilet valve open, water flows in the MPS.
Therefore, the alarm system used on typical commercial applications
will not work for the MPS because simply taking a shower might
cause a typical commercial flow detector to alarm when used with
the MPS.
[0015] In light of this problem, typical residential applications
have two completely different piping systems: (1) a fire sprinkler
piping system, and (2) a domestic piping system. This basically
doubles the number of pipes and the amount of plumbing work which
has to be performed in a typical residential application. The same
set of piping could not previously be used for both systems because
the flow alarm could send false signals when domestic water was
turned on. Alternatively, a residential application could use a
fire detection system (i.e., smoke detector system). However, a
smoke detection system does not alarm when water flows. Therefore,
with a smoke detection system and no flow alarm, the fire
sprinklers could run for days, causing extensive water damage,
while the home owner is away on vacation and no alarm would sound.
Also, smoke detection systems are expensive.
[0016] As noted above, U.S. patent application Ser. No. 09/098,976
filed Jun. 1, 1998, disclosed an Apparatus And Method For
Multi-Purpose Residential Water Flow Fire Alarm. The apparatus for
use as a multi-purpose residential fire suppression water flow
alarm system disclosed in that application was comprised of a
supply side for delivering water under pressure; a multi-purpose
piping system having a system side with common piping for
delivering water from the supply side to a fire suppression side
with one or more sprinkler heads and a domestic side for one or
more domestic uses; a detecting means for detecting fire protection
flow and for distinguishing that flow from a maximum domestic flow,
the detecting means being disposed between the supply side and the
system side; a drain test connection; and an alarm means. The
method of utilizing the apparatus described above was also
disclosed. One of the dependent claims from the above-noted
application, claimed a detecting means comprised of an orifice
plate through which water flows causing a differential pressure
measured by a differential pressure switch so that the flow rate to
the orifice plate is proportional to the differential pressure
allowing a determination of flow rate based on the differential
pressure measured.
[0017] It was disclosed that the flow detection means could utilize
any number of well known flow measurement technologies, such as
U.S. Pat. No. 5,288,469 to Otten et al. The Otten device
incorporates both an orifice plate and a cone-shaped plug around
which the water flows. U.S. Pat. No. 5,419,203 to Carmichael
discloses a device similar to the device disclosed by Otten. Otten
utilizes the Hall effect to measure the displacement of a
displacement piston having incorporated therein a magnet.
Carmichael utilizes strain sensors to measure the strain caused by
displacement of a cone-shaped plug biased by a spring member. As
the flow increases, the cone-shaped plug displaces backwardly in
reaction to the flow putting greater pressure on the spring and
consequently, greater pressure on the pressure sensors incorporated
in the device. The Otten and Carmichael devices have several common
features, namely a chamber having an orifice plate and a
plug-shaped device adapted to be deflected away from the orifice
plate in proportion to the flow rate through the chamber. The flow
measurement means must be simple in both operation and concept so
that it will be inexpensive to build and can be easily programed
and calibrated in the field. The problem with Otten and Carmichael
is that their devices allow flow therethrough the instant pressure
is applied across the orifice plate. As disclosed, they are not
capable of serving as a bypass means for allowing flow only when
the differential pressure exceeds some preset level.
[0018] Critics of the MPS have also noted that it is common for
residential systems to incorporate a water softener or similar
devices (such as filters, chlorination systems, UV purifiers and
the like). Water softeners and similar devices can create
substantial drops in system pressure such that the water supply
flowing through a typical residential system may not be sufficient
for fire protection needs. Therefore, there is a need for a bypass
mechanism which will allow sufficient flow in fire protection
situations to bypass the water softener to supply the fire
protection needs.
[0019] Prior art systems also suffered from problems with freezing.
Where lines were in locations that could reach temperatures below
freezing, it was a common problem to face freezing in the pipes,
which could crack sprinkler heads and/or piping systems. Prior art
systems addressed this problem in a number of ways, including dry
pipe systems, which do not have any water in the piping until fire
is sensed, by placing pipes in locations where they were not
exposed to cold temperatures (for example, by placing insulation
wrap over piping systems in favor of heated spaced below) and the
like.
[0020] In prior art systems, typically, city water or other supply
means are connected to a supply system leading into a structure.
Water typically first flows through an outside gate valve. The gate
valve is typically integrally connected with a water meter, though
the two parts may be completely separate. After flowing through the
gate valve and meter the water passes an exterior wall of the
structure. A main control valve is provided in case it becomes
necessary to shut off all the water in the structure. Though shown
inside the structure the main control valve may also be outside. A
pressure gauge may be provided to monitor water pressure in the
system.
[0021] Where there are both domestic uses and a fire sprinkler
system, a flow splitter divides the water supply into two distinct
streams: (a) a fire side, and (b) a domestic side. Following the
flow splitter a flow detection means is provided on the fire side.
The flow detection means is coupled to an alarm means. Upon
detection of flow by the flow detection means, a signal is sent to
the alarm means, which creates an alarm condition therein. Piping
leads away from the flow detection means to a drain/test
connection. The drain/test connection serves two purposes: it
allows the fire side to be drained, and it allows for simulation of
the flow rate created by the operation of a sprinkler head. Piping
also leads away from the flow detection means to at least one
sprinkler head. A separate set of piping, the domestic side, leads
to one or more domestic uses.
[0022] It is known that domestic uses of water can have a high
enough flow rate to detract from fire protection needs. Therefore,
the prior art also discloses a domestic water supply shut-off
valve, which is effectively incorporated into the flow splitter for
shutting off water supply to the domestic side. Such a shut-off
valve is illustrated by U.S. Pat. No. 5,236,002 to Martin, et
al.
[0023] A typical National Fire Protection Association ("NFPA 13D")
system requires two complete sets of piping, both fire side piping
and domestic piping to be run throughout the structure. These two
pipes running side by side require substantial increased material
and labor costs to install. Further, for an existing structure, it
may be extremely expensive or even impossible to install the second
set of piping required for a fire sprinkler system.
[0024] The NFPA allowed the MPS because, in their estimation, the
cost savings associated with single systems instead of duplicate
systems, would cause the MPS to be installed in more homes, thus
saving more lives. However, the NFPA provides no means for alarming
upon a water flow condition in the MPS, which is a system where
both domestic and fire protection systems use common piping.
[0025] With the MPS, again, a city or other domestic water supply
is provided. The water flows through the outside gate valve and
water meter through the outer wall of the structure. Thence the
water flows through the main control valve. A pressure gauge is
typically provided to monitor water pressure in the system. No flow
splitter is required for the MPS. There is no flow detection means
with the MPS. As noted above, typical flow detection means alarm
upon detection of a minimum flow. Therefore, given the common
piping system in the MPS, typical domestic uses could cause the
prior art flow detection means to send an alarm signal to the alarm
means. NFPA provided for installation of a non-water-flow-based
smoke detection and alarm system for use with the MPS. These
non-water-flow-based smoke detection and alarm systems are
expensive, and they are not capable of detecting flow through one
or more fire protection sprinklers. The inability of a smoke
detection system to detect and enunciate a water flow alarm could
result in extensive water damage to the property.
Parent Applications
[0026] The Parent Applications (Ser. Nos. 09/483,999 and
09/098,976) disclosed the MPS with a water flow alarm. Since they
envisioned the MPS, common piping carried water throughout the
system. After passing through the main control valve, water passed
by a pressure gauge, then through a flow detection means. In
combination the flow detection means and the pressure gauge allowed
for determination of whether the water supply is sufficient for
fire protection needs. The flow detection means was connected to an
alarm means which activated upon the detection of a flow rate
greater than maximum domestic flow. Methods of detecting and
measuring flow and alarming upon excessive flow are illustrated,
for example, in Otten, et al., U.S. Pat. No. 5,228,469. Disposed
after the detection means was a drain test connection. This drain
test connection served the same purpose as it did in the prior art.
The drain test connection also preferably included an orifice plate
with interchangeable orifice plates for simulating different flow
regimes. For example, one orifice plate could simulate the
operation of a single fire sprinkler while another orifice plate
simulated the domestic usage. These interchangeable orifice plates
could then be used to calibrate the operation of the alarm means.
Common piping carried water throughout the system to both domestic
and fire protection uses. Rather than having distinct fire sides
and domestic sides, the Parent Applications disclosed short
sections of pipe split off from the common piping which were
designated as either fire side or domestic side.
[0027] The Parent Applications also disclosed a flow sensor
incorporating a combination orifice flow meter/displacement
magnetic flow sensor in an annular housing. The annular housing was
preferably be composed of a non-magnetic, metallic material, such
as aluminum. Alternatively, the annular housing could be comprised
of a polymer such as CPVC or similar materials. The material of
construction was not critical so long as it did not interfere with
the magnetic activation of the Reed switch. The annular housing had
two ends, and at each end a bushing or reducer adapted to be
threadedly (or by a socket) attached thereto to allow connection of
an inlet pipe at an inlet end of the annular housing and an outlet
pipe at an outlet end of the annular housing. A moving orifice
plate, having a front face and a back face, was adapted to be
received within the annular housing. The annular housing had at
least one section with a continuous diameter defined therein for
receiving the moving orifice plate. The moving orifice plate had a
diameter which was slightly smaller than that of the continuous
diameter section of the annular housing, allowing a sliding motion
therein, but preventing excess fluid to flow around a periphery of
the moving orifice plate. A moving plate opening was defined at or
near the center of the moving orifice plate. An orifice plate
magnet flange having a diameter larger than that of the moving
plate opening was disposed on a back face. Disposed substantially
around and outside the flange was a circular orifice plate magnet.
The moving orifice plate was biased away from the outlet end by a
orifice plate spring. The orifice plate spring was contained
between an interior flange shoulder near the outlet end, and the
orifice plate magnet. Mounted on an exterior portion of the annular
housing was a Reed switch. The Reed switch was attached to the
annular housing by an adjustable attachment means. Adjustment
screws held the adjustable attachment means in place and allowed it
to be loosened for movement of the Reed switch for calibration of
the device.
[0028] The Parent Applications also disclosed another related
embodiment of the combination orifice flow meter/displacement
magnetic flow sensor. This embodiment was adapted to be used in
systems where a water softener or similar pressure drop causing
device is present. The outlet to the water softener was on the
supply side of the sensor, and the inlet from the water softener
was on the system side of the sensor. A "bullet rod" was held in
place by a bullet port within the annular housing. The bullet port
was comprised of an outer annular ring held in place between an
annular shoulder and a bushing, support legs projecting inwardly
from the annular ring, and an inner support ring. An open port area
was defined between each of the support legs. Preferably, the sum
of the open port areas was at least as large as the cross sectional
area of the inlet pipe connected to the sensor, thus, the pressure
drop through the device was minimized. A bullet rod having a head
portion with a leading end and a threaded male end adapted to be
received through the inner support ring was provided. A tail
portion had a threaded female end adapted to threadedly engage the
male end, so that the tail portion is held in place against the
inner support ring. The tail portion also had a tapered end. The
tapered end faced the outlet end of the sensor. The moving orifice
plate opening was sized to receive the tail portion so as to allow
sliding motion of the moving orifice place and also to minimize
flow between the tail and the orifice plate. Thus, as the moving
orifice plate was displaced toward the outlet end by differential
pressure, substantially all of the flow was diverted through the
water softener until the differential pressure displaced the
orifice plate past the tapered end, at which point water flowed
through the orifice in the orifice plate. As discussed below,
preferably two Reed switches were provided, the first for a trouble
alarm, and the second for enunciating the alarm means.
[0029] To reiterate, the problem to be solved by the Parent
Application was provision of a water-flow-based means of alarming
the MPS. In the past, such systems had to utilize two completely
different piping systems: one for domestic uses and one for fire
sprinkler system uses. Previous alarms used in these systems were
designed to create an alarm condition upon the detection of a flow
(commonly 8-10 gpm). Typical domestic flows could have caused an
alarm in a prior art system. Alternatively, prior art systems used
a smoke detection and alarm system which did not have a flow
detector. These systems without a flow detector risked substantial
water damage to the structure if a sprinkler head activated while
no one was in the home.
[0030] The Parent Applications used the principle that domestic
flow rates are much lower than flow rates needed for fire
protection. Using a flow detection means, it was possible to create
an alarm condition only upon detection of flows which are such as
created by fire protection needs. Thus, an alarm condition was not
created when typical domestic uses only were detected.
[0031] Preferably, the Parent Applications also incorporated a
tamper detection means on the main control valve. The tamper
protection means determined whether the main control valve was
closed, and if so, enunciating a trouble alarm. A pressure gauge
was also preferably provided in the system.
[0032] The combination orifice flow meter/displacement magnetic
flow sensor disclosed in the Parent Applications preferably had two
normally open Reed switches disposed thereon for detecting flow as
indicating by displacement of the moving orifice plate. The first
Reed switch was the same as previously disclosed, and enunciates a
fire alarm via the fire alarm means. Preferably, the first Reed
switch also activated a system which contacts emergency response
personnel, such as fire departments. In addition to the fire alarm
Reed switch, a second Reed switch may be provided. The second Reed
switch enunciated a first stage "trouble alarm". Preferably, the
first stage trouble alarm only enunciated within the structure
(i.e., emergency response personnel were not contacted). The
trouble alarm was created if the domestic usage was excessive.
Where the system was used with the MPS, the first stage alarm would
naturally cause anyone in the residence to instinctively shut off
water, for example a shower they may be taking. As another example,
if a resident heard a first stage alarm, and they were washing
dishes, they would most likely shut off the sink faucet. This
natural reaction to the first stage alarm may reduce the water flow
demand below the level where the first stage alarm enunciates,
eliminating the alarm condition. The first stage Reed switch is
displaced a slight distance toward the inlet of the flow sensor
relative to the fire alarm Reed switch. Thus, as the moving orifice
plate is displaced towards the outlet end of the flow sensor, it
will first activate the first stage Reed switch, enunciating the
internal first stage trouble alarm. As the orifice plate continues
to be displaced towards the outlet end, it will next activate the
fire alarm Reed switch, which enunciates the alarm means,
preferably notifying emergency response personnel. The relative
linear displacement of the fire alarm Reed switch and the trouble
Reed switch was to be set in the field so that there was sufficient
differential in the flow which activates the first stage alarm and
the fire alarm to give residents or occupants of the structures
sufficient time to shut off domestic demands before a fire alarm is
created. This two-stage system also serve as a safety back up,
because if one of the alarm stages fail, the other still alerted
residents to the potential alarm condition.
[0033] Tamper detection means on the main control valve preferably
incorporated Reed switches as well. As the handle was turned, a
magnet on the handle activated a normally open Reed switch, causing
it to close, enunciating an alarm notifying the occupants of the
structure that the main control valve had been closed, and the fire
protection system was not being supplied with water. Again, this is
an important safety consideration in residential systems where
small children, unknowing homeowners, and the like can easily turn
off the system without realizing they are shutting off their fire
protection system as well.
[0034] Though the Parent Applications described the inventions
therein with reference to a multipurpose piping system, it should
be understood that the system could be used with any flow-based
system. Further, the flow detection means disclosed herein could be
used with any flow system, not just fire protection systems. That
is, the flow detection means are capable of detecting the flow of
any fluid through a piping system. The piping system could carry
hydrocarbons, solvents, or any other liquid or potentially gaseous
materials for that matter.
[0035] In operation the apparatus disclosed in the Parent
Applications functioned as both a domestic water supply system and
a smoke detection and alarm system. Under normal conditions, the
water flow rate through the flow detection means did not reach the
fire suppression flow rates. When one or more sprinkler heads
activated, the flow detection means detected the increased flow and
sent an alarm to the alarm means. The alarm means enunciated a
visible and/or audible alarm indicating the alarm condition. It is
well known in the prior art to activate a telephone modem-based
system for calling, for example, the fire department, upon
detection of an alarm condition. See, e.g., Otten, U.S. Pat. No.
5,139,044. It was preferable to incorporate such a modem-based
component in the present invention to notify the fire department
and other emergency contacts should a fire alarm condition be
detected. If one or more domestic cutoff valves were included in
the apparatus, the flow detection means also sent a signal to
activate the domestic cutoff valves, shutting off water to one or
more domestic uses and providing more water for the fire
sprinklers.
[0036] When the two-stage alarm system was provided, it was
necessary to calibrate both the first stage trouble alarm and the
first stage Reed switch. The preferred method was to first
calibrate the fire alarm Reed switch. The calibration was very
simple. First, the drain test connection is opened to simulate fire
protection needs, the connection means for the Reed switch were
loosened, and it was moved towards the inlet end of the sensor
until an alarm condition was created. The first stage Reed switch
was then moved a slight distance further towards the inlet end. A
typical domestic demand was then created by using the drain test
connection or flowing water from some number of plumbing fixtures.
As the flow through the drain test connection exceeds the high end
of the expected domestic demand, the first stage Reed switch should
be activated, activating a first stage trouble alarm. If the alarm
is not activated, the first stage Reed switch is moved further
towards the inlet end of the sensor.
Shortcomings of the Prior Art
[0037] In prior systems it was often necessary to provide both a
double check valve element and a flow detection/measurement/control
sensor. Both of the elements increased the cost of this system and
increased the pressure drop through the system. There was a need
for a flow sensor that could both serve as a double check and as a
flow detection or measurement means.
[0038] In multi-purpose piping systems, as well as stand-alone fire
protection systems, there was the problem of stagnation (where
water was to be used for human consumption) of water in the piping
as well as the problem of freezing, where piping was exposed to
temperatures lower than 32.degree. Fahrenheit. Freezing presented
itself as a problem where piping was installed, for example, in an
attic of a residence. There was therefor a need for a system which
provides for the warming of pipes to prevent freezing, as well as
circulation through the pipes to prevent stagnation.
[0039] Another problem that plagued prior art systems was the issue
of retrofitting existing structures for fire protection systems.
Retrofitting for a fire protection system in a typical structure
would be very expensive because, where the freezing issue is a
problem, piping would have to be installed in conduits below the
ceiling of the structure (or at least under insulation) to prevent
the danger of freezing.
SUMMARY OF THE INVENTION
[0040] It is therefore an object of the invention to provide an
apparatus for flow detection and measurement. It is also an object
to provide a method for using the disclosed apparatus in
multipurpose piping water flow fire alarm systems. The apparatus
and method overcome one or more of the disadvantages of the prior
systems.
[0041] It is an object of the present invention to provide an
apparatus for flow detection and measurement. The apparatus for
flow detection and measurement can incorporate a bypass means for
allowing additional flow to pass through the flow measurement
device as needed. When water is allowed to flow through the bypass
means, an alarm may be enunciated should the flow reach a specified
level. The objects of the apparatus are accomplished by providing a
moving orifice plate with a magnet moving in cooperation therewith.
The magnet activates a Reed switch on an external surface of the
flow sensor when the moving orifice plate is displaced a sufficient
distance by the flow passing through the sensor. When the water
demand exceeds that which can flow through the primary path, the
moving orifice plate is displaced beyond bullet rod allowing flow
through the orifice.
[0042] It is a further object of the invention to provide a flow
sensor which can serve as a double check valve. This object of the
invention is achieved by providing a moving seat, in cooperation
with the moving orifice plate, for providing two back flow
prevention means. When water moves through the flow sensor in the
desired direction, the moving seat allows water to pass thereby,
and when sufficient water flows through the sensor, the moving
orifice plate is displaced so that water can pass through the
orifice therein. When water flows in the undesired direction, the
moving seat is biased to cause a sealing action of a check o-ring
against a check shoulder seat. Similarly, the moving orifice plate
is biased so as to create a seal between an outer seat and an outer
orifice o-ring, as well as between an inner seat and an inner
orifice o-ring. Thus, in combination, the moving seat and the
orifice plate provide a double check. Incorporating the double
check technology, a single flow sensor can serve as a flow
measurement device, a double check valve, a bypass means, as well
as creating an electronic output signal for enunciating an alarm or
the like.
[0043] It is an object of the present invention to provide a fire
protection piping system having a water supply, a means for heating
water, at least one fire protection sprinkler, a common piping
means for receiving water from the supply, passing it through the
heating means and delivering it to at least one fire protection
sprinkler, and circulating means for circulating water through the
common piping back to the heating means to maintain a specified
minimum temperature in the common piping. By providing these
elements, the danger of water freezing in the common piping is
eliminated. In one embodiment, the circulation means comprises a
pump controlled by a temperature measurement means for determining
when the temperature of water in the piping drops below the minimum
temperature specified. The controller engaging the pump which
re-circulates the water in the piping through the heating means
once the temperature drops below the desired level. At the same
time, the recirculating of hot water through the system also
eliminates the problem of stagnation.
[0044] It is also an object of the present invention to provide the
foregoing advantages in a system where at least one domestic uses
is also supplied with hot water by the common piping. When the
present system is used in a multi-purpose piping system, homeowners
have the added benefit of instant hot water from a faucet or the
like.
[0045] It is an object of the present invention as well to provide
a flow sensor which incorporates at least a single stage means for
enunciating an alarm. The flow sensor may incorporate as many as
three or more levels of alarm for the taking of various actions by
the system upon the detection of the specified level of flow
required to enunciate the alarm.
[0046] It is also an object of the present invention to provide a
means to compensate for pressure drops in a typical MPS. More
particularly, typical pressure drops include, but are not limited
to, a water softener which may be placed in line in the system.
Water softeners are typically used in multi-purpose systems to
improve the quality of water for domestic use in the residence. In
addition to water softeners, pressure drops may include filters, UV
treatment of water, and the like. There are many reasons why people
want to treat water coming into their homes for domestic purposes.
Many of these treatment means will reduce the pressure of the water
through the MPS system. Thus, there may be a need for fire
protection flows to bypass these pressure drops in the system, or
to at least compensate for them. The present invention takes these
types of pressure drops into account by providing a bypass means.
In typical domestic flow situations, the entire flow of the water
supply goes through the treatment method in question, such as a
water softener. However, when the system side pressure drops below
a set level, a relief allows additional flows through a lower
pressure drop path.
[0047] By the same token, devices previously available for the
measurement of flow caused another pressure drop. As noted above,
pressure drops in the MPS can prevent sufficient flow from being
available to satisfy fire protection needs. Therefore, it is also
an object of the present invention to provide a volume flow
detection and measurement means for use in the MPS which have
minimal pressure drops. The flow detection means discussed are very
simple in operation and easy to calibrate in the field. They may be
used to provide a read out of the flow, or may simply provide an
alarm when fire protection flows are detected.
[0048] It is also an object of the present invention to provide a
flow measurement device with a higher capacity still for use in
standard wet pipe systems. Under some circumstances, it may be
desirable to use an expanded chamber system along with the orifice
plate. In these systems, as the orifice plate is deflected
backwardly by the water pressure, it moves into an area of expanded
cross-section where the water can flow not only through the center
of the orifice plate, but around the edges thereof. This expanded
area minimizes the pressure drop through the flow sensor at high
demands, such as is the case where multiple sprinkler heads may
have activated.
[0049] It is an object of the invention to provide a system which
can incorporate both a water softener and use of heated water from
the hot water heater in the structure. As noted above, the bypass
means may be the flow sensor as described herein. Alternatively,
the bypass means may comprise a flow sensor for measuring fluid
flowing through the common piping, a normally closed valve, and a
controller in communication with the flow sensor and in a
controlling position of the valve for opening the valve when demand
for water exceeds the capacity of flow through either the heating
means and/or the water softener. This valve-based bypass system
requires mechanical intervention, so it is not as simple as the
system incorporating the valve and the flow sensor with integral
bypass means. However, it may be desirable in some
applications.
[0050] A system for providing circulation of water around fire
protection sprinklers, the system comprising, common piping
carrying water, which water is caused to flow at periodic
intervals; a head fitting receiving a fire protection sprinkler
therein and further defining a chamber therein in communication
with the sprinkler; supply and return lines for supplying water to
and returning water from the head fitting; and a pump means for
using the velocity head created by water flowing through the common
piping to pump water to the head fitting causing circulation there
through as a result of and in cooperation with flow through the
common piping, is disclosed. As disclosed, the circulation systems
does not require any mechanical input. That is, no pumps or motors
are required for the pumping system. However, it is anticipated
that in some cases it may be desirable to use a mechanical pump
based on either electrical, air, or similar power means. In those
cases, the pump will not rely on the velocity head of water flowing
through the common piping.
[0051] It is also an object of the invention to provide a
integrated system incorporating the above-noted elements of the
invention and having a two-stage alarm for enunciating a pre-alarm,
as well as a full-blown fire alarm. The integrated system has two
sensors on the flow detection device, the first sensor enunciating
a trouble alarm when a specified flow is created, and if the flow
further increases, a second sensor enunciating a fire alarm, which
also preferably calls emergency response personnel. The first
trouble alarm is audible only in the residence or structure where
the system is deployed. Preferably, as noted, the second fire alarm
will contact emergency personnel, possibly via a telephone
modem-type connection. The integrated system also preferably
incorporates a tamper switch on a valve incorporated in the system
to shut off the flow thereto. The tamper switch will enunciate if
water flow to the fire protection system is shut off.
[0052] Finally, it is an object of the present invention to provide
a shut off valve to automatically prevent water from flowing to a
lawn sprinkler should a trouble or fire alarm be enunciated. The
shut off valve would be activated by a controller or directly by
the signal sent from the flow sensor, indicating that there was
either a trouble alarm or a fire alarm condition. Where this shut
off valve is incorporated into the present system, it may be
preferable to have a normally closed Reed switch along with the
other Reed switches, as shown on the flow sensor in FIG. 1, to
close the normally closed shut off valve when a magnet is displaces
sufficiently far to activate either the trouble alarm or the fire
alarm.
[0053] There have thus been outlined, rather broadly, the more
important features of the invention in order that the detailed
description thereof that follows may be better understood, and in
order that the present contribution to the art may be better
appreciated. There are, of course, additional features of the
invention that will be described hereinafter and which will form
the subject matter of the claims appended hereto.
[0054] In this respect, before explaining at least one embodiment
of the invention in detail, it is to be understood that the
invention is not limited in this application to the details of
construction and to the arrangements of the components set forth in
the following description or illustrated in the drawings. The
invention is capable of other embodiments and of being practiced
and carried out in various ways. Also, it is to be understood that
the phraseology and terminology employed herein are for the purpose
of description and should not be regarded as limiting. As such,
those skilled in the art will appreciate that the conception, upon
which this disclosure is based, may readily be utilized as a basis
for the designing of other structures, methods and systems for
carrying out the several purposes of the present invention.
Additional benefits and advantages of the present invention will
become apparent in those skilled in the art to which the present
invention relates from the subsequent description of the preferred
embodiment and the appended claims, taken in conjunction with the
accompanying drawings. It is important, therefore, that the claims
be regarded as including such equivalent constructions insofar as
they do not depart from the spirit and scope of the present
invention.
[0055] Further, the purpose of the foregoing abstract is to enable
the U.S. Patent and Trademark Office and the public generally, and
especially the scientist, engineers and practitioners in the art
who are not familiar with patent or legal terms or phraseology, to
determine quickly from a cursory inspection the nature and essence
of the technical disclosure of the application. The abstract is
neither intended to define the invention of the application which
is measured by the claims, nor is it intended to be limiting as to
the scope of the invention in any way.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] In the drawings:
[0057] FIG. 1 is a schematic diagram of one embodiment of the
present invention.
[0058] FIG. 2 is a detailed cross-sectional drawing of a passive
pump for use in the present invention to circulate water around and
to sprinkler heads.
[0059] FIG. 3 is a detailed cross-sectional view of the head
fitting to which the sprinkler head is attached to allow
circulation thereto.
[0060] FIG. 4 is a detailed cross-sectional view of a flow sensor
having an integral bypass means therein.
[0061] FIG. 5 is a detailed cross-sectional view of a flow sensor,
which allows flow therethrough when the pressure drop across the
flow sensor exceeds a preset limit.
[0062] FIG. 6 is a front view of the orifice plate used in the flow
sensors shown in FIGS. 4 and 5.
[0063] FIG. 7 is a back view of the orifice plate shown in FIGS. 4
and 5.
[0064] FIG. 8 is a front view (as well as a back view since the
front and back views are identical) of a bullet port used in the
flow sensor shown in FIGS. 4 and 5 of the present invention.
[0065] FIG. 9 is a schematic of an alternative configuration of the
present invention. FIG. 10 is a schematic of still another
alternative configuration of the present invention.
[0066] FIG. 11 is a cross-sectional view of a flow sensor
incorporating a double check valve.
[0067] FIG. 12 is a detail side view of the moving seat for use
with a double check valve.
[0068] FIG. 13 is a detail front view of the moving seat for use
with a double check valve.
[0069] FIG. 14 is a detail back view of the moving seat for use
with a double check valve.
[0070] FIG. 15 is a detail side view of the moving orifice plate
for use with a double check valve.
[0071] FIG. 16 is a detail front view of a moving orifice plate for
use with a double check valve.
[0072] FIG. 17 is a detail back view of a moving orifice plate for
use with a double check valve.
[0073] FIG. 18 is a detail side view of the bullet port for use
with a double check valve.
[0074] FIG. 19 is a detail front view of the bullet port for use
with a double check valve.
[0075] FIG. 20 is a detail back view of the bullet port for use
with a double check valve.
[0076] FIG. 21 is a cross-sectional view of another embodiment of a
flow sensor incorporating a double check valve.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0077] A flow sensor, from which the flow sensor disclosed herein
was described in U. S. patent application Ser. No. 09/483,999,
filed Jan. 18, 2000. That application disclosed a flow sensor,
which could be used with a multi-purpose piping system for a fire
suppression system/domestic water supply system in a structure. The
device was disclosed as being used in a fire protection system, but
it was noted that the sensor could be used in any flow measurement
situation as well as in situations where a bypass means was
desirable. The device disclosed more fully hereinafter, is intended
to, and certainly can, be used in any appropriate flow measurement
situation. It need not be a fire protection system, and the fluid
need not be water. For example, in a petrochemical facility, a
petrochemical may be passed through a reactor unit to cause a
chance in its chemical structure. However, should the reactor
become plugged, it may become desirable to have a bypass mechanism
which allows the petrochemical to be vented to an emergency flare
system, rather than causing a rupture or other failure of the
reactor vessel. Such an application would be an appropriate use for
the present flow sensor. The operation of the flow sensor described
in the Parent Application is more fully described in the sections
below.
[0078] One embodiment of a fire protection system incorporating the
apparatus is illustrated in FIG. 1. The water from the water supply
100 first flows through a flow sensor 101a passing through an inlet
softener line 104 to a water softener 102 or similar water
treatment or processing device and thence through the outlet
softener line 106 back through the flow sensor 101a. The operation
of the flow sensor 101a will be more fully described hereinafter,
but for the present time it is sufficient to say that the flow
sensor 101a typically directs water through the inlet softener line
104 through the water softener 102 and then back through the sensor
to a first pipe section 108. However, whether there is an excessive
water demand in the system, for example such as one caused by the
operation of a fire protection sprinkler, there is a mechanism
incorporated in the flow sensor 101a which allows water to bypass
the water softener 102 increasing the flow rate through the system.
The water, which is passed through the water softener 102, is next
split, some of it passing into the cold water piping 110, and the
rest of it passing into a second pipe section 112.
[0079] The water from the second pipe section 112 next passes
through a second flow sensor 101b. A check valve 148 may also be
incorporated in the second pipe section 112. The check valve 148
prevents back flow of water, which potentially could be stagnate
from the fire protection system, to the cold water piping and/or
the water softener. The second flow sensor 101b passes water down
through a water heater 114 via an inlet heater line 116, and back
to the sensor via an outlet heater line 118. Again, the second flow
sensor 101b incorporates a bypass means which allows water to
bypass the water heater where there is an excessive demand. After
being heated, the water passes into a multi-purpose pipe section
120. Attached to the multi-purpose pipe section 120 are typical
domestic uses such as a shower head 122 and a faucet 134. Other
uses, such as toilets, dishwashers, washing machines, and the like
may also be attached to the multi-purpose pipe section 120. Also in
communication with the multi-purpose pipe section 120 are one or
more sprinkler heads 128. As shown in FIG. 1, sprinkler heads are
in communication via a passive pump 124 and a head fitting 126 with
a multi-purpose pipe section 120. The operation of the passive pump
124 in cooperation with the head fitting 126 and the sprinkler
heads 128 will be more fully described hereinafter. However, the
purpose of the passive pump is to utilize the velocity head of
water flowing through the multi-purpose pipe section 120 to
circulate water to and around the sprinkler heads 128 to minimize
stagnation thereat.
[0080] As shown in FIG. 1, two flow sensors are incorporated into
the multi-purpose piping system. If there is no water softener,
there will not be a need for the flow sensor 101a. The only flow
sensor 101b will be on the hot water heater. Alternatively, it may
be desirable to have only one flow sensor present at the water
softener. In such a case, the flow sensor at the water softener
will also measure the cold water flow, potentially contributing to
more false alarms in the multi-purpose alarm system. However, this
may be desirable where the risk of false alarms is not substantial,
and the cost savings is sufficient enough to justify a single
sensor at the water softener only. It is not believed that the hot
water heater will cause a significant pressure drop in the flow
therethrough. Therefore, the bypass means at the hot water heater
is not believed to be necessary to ensure that adequate flow is
available for fire protection needs. Rather, as shown, the
advantages that the flow sensor placed on the hot water heater only
measures the flow through the hot water domestic uses, as well as
the flow to the fire protection sprinklers. Thus, the chance of a
false alarm is minimized.
[0081] From the passive pump 124, water is passed to a head fitting
126. The water passes to the head fitting 126 from the
multi-purpose pipe section 120 via the head supply line 130. It is
returned to the multi-purpose pipe section 120 via the head return
line 132. A reverse-j fitting 164 supplies water from the head
fitting 126 to the sprinkler head 128. The purpose of the reverse-j
fitting 164 is to cool the water supplied to the sprinkler head 128
to insure that the sprinkler head is not activated by the
temperature of the water supplied thereto. Most sprinkler heads are
set to activate at a temperature of 155.degree. Fahrenheit. While
it is not anticipated that hot water flowing through the
multi-purpose piping system will exceed that temperature, the
reverse-j fitting 164 helps to insure that just in case the water
does exceed that temperature, the fire sprinkler is not
inadvertently activated by water passing thereto.
[0082] As shown, a thermocouple 136 in communication with the pump
controller 138 and control wiring 140 operates to ensure that a
minimum desired temperature is maintained in the common piping 120.
The thermocouple 136 measures the temperature of water in the
common piping 120. If the temperature of the water drops below a
preselected level (preferably at least 40.degree. Fahrenheit), the
pump controller 138 initiates the action of a pump 144. The pump
144 draws water from the common piping via a pump inlet pipe 142. A
pump outlet pipe 146 directs water through a check valve and a
return pipe 150 so that it is recycled through the water heater
114. The return pipe 150 connects to the inlet heater line 116 to
complete the circuit. Thus, water moved by the pump 144 through the
water heater 114 is reheated to maintain a minimum temperature in
the multi-purpose pipe section 120.
[0083] An alternative embodiment is also shown in FIG. 1. The
alternative embodiment includes a return leg supply pipe 152 and a
return leg flow sensor 154. The return leg supply pipe 152 may be
in communication with the first pipe section 108. The return leg
flow sensor 154 normally prevents any water from flowing directly
from the first pipe section 108 through the return leg supply pipe
152 into the multi-purpose pipe section 120. However, when an
excessive water demand is made on the multi-purpose pipe section
120, the pressure may drop low enough so that the return leg flow
sensor 154 allows water to pass there through directly from the
first pipe section 108, bypassing the flow sensor 101b and the
other elements of the water heater system. Alternatively, the
return leg flow sensor 154 may draw water from the multi-purpose
pipe section 120 at a point adjacent to the outlet from the flow
sensor 101b.
[0084] As used herein, the multi-purpose pipe section 120 will
often be referred to as "common piping." The "common piping" may
include the second pipe section 112, the inlet heater line 116, the
outlet heater line 118, the multi-purpose pipe section 120, the
pump inlet pipe 142, the pump outlet pipe 146, as well as the flow
sensor 101b. Further, in the embodiment shown in FIG. 1, the common
piping includes all piping elements excluding the cold water
system, and also excluding piping related to the water softener
system. As noted above, in some circumstances it may be desirable
to have the flow sensor with the fire alarm enunciation means
located at the water softener. Where the flow sensor with the fire
alarm enunciation means is located at the water softener, the term
"common piping" will include the cold water piping, as well as the
piping related to the water softener.
[0085] The flow sensor 101b incorporates a trouble Reed switch 156
and a fire Reed switch 158. An alarm annunciator is in electronic
communication with the trouble alarm 160 and a fire alarm 162.
Preferably, the fire alarm 162 will also have a remote notification
feature, which could advise the fire department, for example, that
a fire alarm condition exists in the structure. As shown, as a
differential in the linear placement of the fire Reed switch 158
compared to the trouble Reed switch 156. This linear placement can
be more clearly seen in FIG. 4. The remote notification feature
will incorporate the use of a modem or other electronic dialing
means to notify the police and play, for example, a pre-recorded
message notifying the police and/or fire department of the fire
alarm condition in the structure.
[0086] The operation of the passive pump 124 is illustrated in FIG.
2. The passive pump 124 is connected in-line in the multi-purpose
pipe section 120. The passive pump 124 includes a body 200 defining
a chamber 202 therein. The chamber 202 has an inlet 204 for
receiving water from the multi-purpose pipe section 120 and an
outlet 206 for passing on water to continue on through the
multi-purpose pipe section 120. Also in communication with the
chamber 202 is a head supply line 130 and a head return line 132.
These lines are connected to the head outlet 208 and head return
210, respectively, in communication with the chamber 202. As shown,
the head outlet 208 is simply a hole passing through a wall of the
chamber 202 in communication with the head supply line 130. The
head return 210, however, extends inwardly into the chamber 202.
The opening 212 is thus directed toward the outlet 206 from the
chamber 202. The head return 210 this has the appearance of a
"Pitot tube." In cooperation, the head outlet 208 and the head
return 210 work as a passive pump 124 using the velocity of fluid
passing through the multi-purpose pipe section 120 to circulate
water through the head supply line 130 and the head return line
132. Alternatively, the head outlet 208 could be formed as a Pitot
tube facing the inlet 204 so that the velocity head pushes the
water through the head outlet 210 and around the sprinkler head.
There are certainly other ways that the velocity head of water
passing through the multi-purpose pipe section 120 could be used to
pump water around the sprinklers. Such ways as are commonly known
to use a velocity head to cause water movement are intended to be
incorporated in the spirit of this invention.
[0087] FIG. 3 shows the head fitting 126 with a reverse-j fitting
164 and a sprinkler head 128 attached thereto. The head fitting 126
is comprised of a fitting body 300. The fitting body 300 defines
therein a fitting chamber 302 with a fitting inlet 304 and a
fitting return 306. The head supply line 130 feeds the fitting
inlet 304, and the head return line 132 carries water from the
fitting return 306 back to the passive pump 124. The reverse-j
fitting 164 extends upwardly from the body 300, then depends
downwardly therefrom. The sprinkler head 128 is attached to the
distal end 308 of the reverse-j fitting 164. As noted above, the
reverse-j fitting 164 prevents activation of the sprinkler head 128
by hot water.
[0088] FIG. 4 is a cross-sectional view of a flow sensor 101b. The
flow sensor 101b is comprised of an annular housing 402, for which,
as shown, is comprised of a first housing portion 440 and a second
housing portion 442. The first and second housing portions, 440 and
442, are connected at a flange 444, via flange bolts 446. The
annular housing 402 has a main inlet port 404 for receiving water
from a supply source. The annular housing 402 also has a main
outlet port 406 for delivering water to downstream needs. Disposed
on sides of the annular housing 402 are a device outlet port 408
and a device inlet port 410. The annular housing 402 also has a
first gauge port 412 and a second gauge port 414 for attachment of
pressure gauges, flow gauges, or such other gauges as may be
desirable to attach to monitor the operation of the flow sensor
101. Defined within the annular housing 402 is a chamber 416. A
bullet port 418 is seated on a annular seat 424 at the flange 444.
The bullet port 418 is illustrated in FIG. 8, below. Attached to
the bullet port 418, using a bullet rod bolt 422 is a bullet rod
420. A magnet 426 and orifice plate 428 are biased against the
bullet port 418 by a spring 432, which rests on a spring seat 448.
The orifice pate 428, which is shown generally in FIGS. 6 and 7,
has defined thereon a magnet seat 430 for maintaining communication
with the magnet 426.
[0089] In a preferred embodiment, two Reed switches are disposed on
the outside of the annular housing 402. The Reed switches are
attached to the housing using Reed switch clips 438. The Reed
switch clips 438 are simply unshaped components which snugly
receive the generally round Reed switches, and which are attached
to the annular housing 402 with screws. Loosening the screws on the
Reed switch clips 438 allows for the Reed switches to slide closer
to or farther away from the main inlet port 404 of the annular
housing 402. Note there is a linear displacement between the
trouble Reed switch 156 and the fire Reed switch 158. Thus, as the
moving orifice plate 428 is displaced towards the outlet end by
increased flow, the magnet in cooperation therewith first
enunciates the trouble alarm, then, as the flow continues to
increase, it later enunciates a fire alarm.
[0090] As will be more fully described in the Operation section
below, water flows into the flows sensor 101 through the main inlet
port 404. In typical operation, it is directed out through the
device outlet port 408 through a flow device, such as a hot water
heater or a water softener. Once the water has passed through the
device, it is returned to the flow sensor 101 through the device
inlet port 410. It then continues out of the flow sensor 101
through the main outlet port 406. However, when the downstream
water demand exceeds the capability of water to flow through the
device, the orifice plate 428 begins to be biased towards the
outlet end by the differential pressure. Once the differential
pressure becomes large enough, the orifice plate is displaced past
the end of the bullet rod 420, allowing water to flow through the
orifice, to increase the flow passing through the flow sensor
101.
[0091] FIG. 5 illustrates a return leg flow sensor 154, which is
somewhat like the flow sensors 101a and 101b. The primary
difference in the configuration shown is that the flow sensor has
the magnet on the inlet side of the orifice plate, while the return
leg flow sensor 154 has the magnet on the outlet side of the
orifice plate. In addition, the main difference is that the return
leg flow sensor 154 does not have device inlet and outlet ports,
410 and 412, respectively. The sole purpose of the return leg flow
sensor 154 is to allow additional water to flow through the orifice
when the pressure at the outlet drops below some specified level.
As noted, it could draw water from a different part of the system,
as may be desirable in a given application.
[0092] The return leg flow sensor 154 is comprised of a first
housing portion 500 and a second housing portion 502. It
incorporates an inlet 504 and an outlet 506. Disposed within the
sensor is a bullet port 508 having an outer annular ring 510, and
to which is attached a bullet rod 512. The bullet rod 512 has a
head portion 514 and a tail portion 516, and is secured to the
bullet port 508 by a bullet rod bolt 518. As shown, the bullet rod
bolt 518 screws into the tail portion 516 using bullet rod threads
520 defined in the tail portion 516. Again, the orifice plate 524
with a magnet 526 adjacent thereto is biased against the bullet
port 508 by a spring 528.
[0093] FIGS. 6, 7, and 8 illustrate in detail, the construction of
the orifice plate 428 and the bullet port 418. The orifice plage
428 incorporates a magnet seat 430 on a first face 602. Of court,
the orifice plate 428 also incorporates an orifice 600, which is
simply a hole passing there through. Preferably, the orifice 600
will have a diameter equal to the inside diameter of the
multi-purpose piping 120, though a smaller orifice may be
functional. A circular magnet is adapted to fittingly engage the
magnet seat 430 and rest against the first face 602. The second
face 700 of the orifice plate 428 is illustrated in FIG. 7. The
magnet seat 430 is shown in outline in this view.
[0094] FIG. 8 illustrates the bullet port 418. The bullet port 418
is comprised of an outer annular ring 800, and support legs 804
extending inwardly and attach to an inner support ring 802, which
defines a bullet bolt hole 806 therein. Flow holes 808 are therefor
defined in the bullet port 418, which allow water to pass there
through. As shown, the support legs 804, both have a wide profile.
However, it is preferable that the support legs 804 have a thin
cross-section facing the flow of fluid entering the bullet port
418. That is, instead of having the thicker portion of the support
legs face the fluid flow towards the support legs, they could be
turned so that the thinner cross section of the support legs faces
the flow and the wider section is perpendicular to the direction of
the flow. This would minimize the pressure drop through the bullet
port.
[0095] An alternative feature for the present invention is
illustrated in FIG. 9. As shown, the invention is incorporated in
the water softener portion of the system. However, should a system
be built without a water softener, the present invention could be
incorporated on the water heater portion of the system, to-wit:
instead of the valve being disposed in the inlet water softener
line 104 it would be disposed in the inlet heater line 116.
However, as shown, the water supply enters the sensor 101a. The
inlet softener line 104 carries the water from the sensor 101a to
the water softener 102. An actuated value 900 is disposed in the
inlet softener line 104. An actuated valve 900 is controlled by a
controller 902. The controller has at least two settings: first, a
setting for when the structure is occupied; an second, a setting
for when the structure is unoccupied. In a preferred embodiment,
the controller is a security system, commonly installed in
residences and the like. When the controller 902 is a security
system, it will preferably have three settings: first, a security
setting for use at night primarily where the residents want to be
alerted if there is a security breach of the residence, but it is
necessary to allow flow through the multi-purpose piping systems;
second, a disarm setting where the residents do not want the
security system to alert them of any security breaches, and the
residents want to allow flow through the multi-purpose system; and
third, a setting where minimal flow is desired, and the residents
want to be alerted of any security breaches. The third setting
would typically be used when the residents have left the structure
during the day for work or for extended periods, such as for a
vacation. In the first and second settings, the controller 902
operates the actuated valve so as to allow flow therethrough when
there is a water demand in the structure. In the third setting, a
demand for flow in the structure, above some minimal flow allowed,
for example, for refilling toilets and supplying an ice maker,
instead of activating the actuated valve, instead activates as
alarm means. The alarm may either be solely within the structure or
it may alert external authorities, such as the fire department. In
this mode, it is presumed that any significant flow through the
multi-purpose piping system is either caused by a fire or by a
piping leak in the structure. The leak could be, for example, the
breaking of a supply line for a clothes washer.
[0096] FIG. 10 illustrates still another potential embodiment of
the present invention. Again, the device is shown where a water
softener is provided, but if the water softener is not present, the
analogous components of the water heater will be substituted for
the water softener. The water supply 100 passes through a main
control valve with Reed switch 1008. The main control valve with
tamper Reed switch 1008 is in communication with a controller 1010.
From there, it passes through a flow sensor 1000. The flow sensor
1000 incorporates a valve Reed switch 1002, a trouble Reed switch
1004, and a fire Reed switch 1006. When the flow through the flow
sensor 1000 exceeds the level, which can be anticipated to be met
by the water softener 102, the valve Reed switch 1002 sends a
signal to the controller 1010 to open a bypass valve 1012. The
bypass valve 1012 serves the same function of as the flow sensor
101b in FIG. 1, to-wit: when the demand for water exceeds the
ability of the water softener to produce it, the valve allows
additional flow, for example for fire protection needs. If the
demand becomes still greater, a trouble Reed switch 1004 is
activated enunciating a trouble alarm 1114. Finally, if the flow
continues to increase, the fire Reed switch 1006 is activated
enunciating a fire alarm 1116, which may preferably notify external
authorities such as the fire department. The three-stage Reed
switch would not be useful with the flow sensor shown in FIG. 4
because the third Reed switch is provided to activate a valve. No
valve actuation is required for the operation of the flow sensor
101b, rather it is operated mechanically by selecting an
appropriate spring tension to allow the system to operate at the
desired pressure. However, the Reed switch on the main valve 1008
is desirable to notify occupants that the valve supplying the fire
suppression system is closed.
[0097] FIG. 11 illustrates a double check configuration of a flow
sensor. The double check flow sensor 1100 is generally shown in
FIG. 11. It is comprised of substantially a first housing portion
1102 and a second housing portion 1104. At an end of the first
housing portion 1102 is a main inlet port 1106, and a main outlet
port 1108 is disposed at an end of the second housing portion 1104.
In cooperation, the first housing portion 1102 and second housing
portion 1104 define a chamber 1110 therein. Disposed in the chamber
1110 is a bullet port 1112 integrally connected to a bullet rod
1114. The bullet rod 1114 defines therein a cylinder 1116. A moving
check 1118 has a check piston 1122 which is slidingly received
within the bullet cylinder 1116. A check o-ring 1120 is disposed on
the moving check 1118 for sealing against the check shoulder seat
1136. A check spring 1124 disposed in the bullet cylinder 1116
biases the moving check 1118 towards the check shoulder seat 1136.
Disposed between the bullet port 1112 and the main outlet port 1108
is a moving orifice plate 1130. On the moving orifice plate 1130
are an outer orifice o-ring 1132 and an inner orifice o-ring 1134.
An orifice spring 1138 biases the orifice plate 1130 in cooperating
a magnet 1140 towards the main inlet port 1106, and away from the
main outlet port 1108.
[0098] The moving check 1118 is generally shown in FIGS. 12 through
14. FIG. 12 is a cross-sectional view of the moving check 1118. It
incorporates a leading edge 1200, as well as a piston end 1202
opposite from the leading edge 1200. A shoulder 1204 is also
defined. A periphery 1206 extends around the terminal portion of
the leading edge 1200. The check piston 1122 is sized to be
slidingly received within the bullet cylinder 1116. The check
o-ring 1120 is sized so as to sealingly seat against the check
shoulder seat 1136. FIG. 13 is a front view of the moving check
1118 showing the leading edge 1200 and the check o-ring 1120. FIG.
14 is a rear view of the moving check 1118 showing a shoulder 1204
and the piston end 1202.
[0099] FIGS. 15 through 17 illustrate the moving orifice plate
1130. FIG. 15 is a detailed cross sectional view of the moving
orifice plate 1130. The first face 1500 faces the main inlet port
1106. Disposed thereon are an outer orifice o-ring 1132 and an
inner orifice o-ring 1134. A second face 1502 is opposite the first
face 1500. An orifice 1504 passes from the first face 1500 to the
second face 1502, defining a hole therethrough. The orifice 1504 is
sized to slidingly receive the bullet rod 1114 therein.
[0100] FIGS. 18 through 20 generally illustrate the bullet port
1112. FIG. 18 is a detailed cross sectional view of the bullet port
1112. An outer annular ring 1800 and an inner support ring 1802 are
generally shown. Extending away from the inner support ring 1802 is
the bullet rod 1114. The outer annular ring 1800 defines an outer
seat 1804, and the inner support ring 1802 defines an inner seat
1806. The outer orifice o-ring 1132, and the inner orifice o-ring
1134 are designed to sealingly engage the outer and inner seats
1804 and 1806, respectively. At a terminal portion of the bullet
rod 1114, a rod end 1808 is defined. It is anticipated that the rod
end 1808 will be closed, though there may be a hole therethrough to
allow the check piston 1122 to freely move within the bullet
cylinder 1116 without creating a vacuum. FIG. 19 is a front view of
the bullet port 1112 showing the support legs 1900, and the flow
holes 1902 defined by void spaces surrounded by the support legs
1900, the outer annular ring 1800 and the inner support ring 1802.
FIG. 20 is a back view of the bullet port 1112, again showing the
same features, as well as showing the rod end 1808.
[0101] FIG. 21 illustrates an alternative embodiment of a double
check flow sensor. As shown in FIG. 21, a nylon-coated magnet
serves both as the source of the magnetic field and as the moving
orifice plate--a combination orifice plate/magnet 2130. The flow
sensor 2100 is comprised of a first housing portion 2102 and a
second housing portion 2104. Defined within the two housing
portions is a chamber 2110 with a main inlet port 2106 and a main
outlet port 2108. A bullet port 2112 is fixed at a juncture between
the first and second portions 2102 and 2104. The bullet port 2112
incorporates a bullet rod 2114 extending outwardly therefrom.
Defined within the bullet rod is a bullet cylinder 2116 for
slidingly receiving the check piston 2122 portion of a moving check
2118. A check o-ring 2120 is disposed on the moving check for
sealing engagement with a check shoulder seat 2136. An
orifice/magnet spring 2138 is disposed within the chamber 2110 for
biasing the orifice plate/magnet 2130 toward the main inlet port
2106 and away from the main outlet port 2108. Similarly, a check
spring 2124 is disposed in the bullet cylinder 2116 for biasing the
moving check 2118 toward the main inlet port 2106 and away from the
main outlet port 2108. A Reed switch 2140 is shown disposed on an
outer wall of the second housing portion 2104.
Operation
[0102] In operation, water flows into the system from a water
supply 100 to a flow sensor 101a. Typically, a flow sensor 101a
diverts water through an inlet softener line 104 to the water
softener for treatment, however, when a demand exceeds the ability
of water to flow through the water softener, a bypass mechanism
incorporated in the flow sensor 101a allows water to short circuit,
and not pass primarily through the water softener, but flow through
to the first pipe section 108. Similarly, the flow sensor 101b
receives water from the second pipe section 112. Typically, water
is diverted downward through the inlet heater line 116 through a
water heater for heating, back up through the outlet heater line
118, and then on to the multi-purpose pipe section 120. However,
when the demand for water exceeds the ability of water to flow
through the water heater, a bypass mechanism allows water to flow
from a second pipe section 112 through the flow sensor 101 to the
multi-purpose pipe section 120.
[0103] This bypass mechanism is allowed to occur by the operation
of a flow sensor 101, the design of which is shown generally in
FIG. 4. The bypass mechanism of the flow sensor 101 operates
without the need for any electronics or any external sensors.
Rather, an orifice plate 428 has an orifice 600, which is adapted
to closely receive a bullet rod 420. Once the orifice 600 has
received the bullet rod 420, water cannot pass there through. A
spring 432 is adapted to bias the orifice plate 428 towards a
bullet port 418. Therefore, in a no-flow condition, the orifice
plate 428 is held against the bullet port 418 by the spring 432.
However, as water begins to flow around the bypass mechanism
through a device, a pressure drop caused by a restriction is
developed between the main inlet 404 and the main outlet 406, which
forces the orifice plate 428 to compress the spring 432 backwardly
towards the main outlet 406. If the pressure difference becomes
large enough, the orifice plate 428 is displaced backwardly far
enough so that the orifice plate 428 clears the bullet rod 420 and
water can flow through the orifice 600.
[0104] A magnet 426 is received against the orifice and seated on a
magnet seat 430. As shown in FIG. 4, the magnet 426 is on the inlet
side of the orifice 600, but it may also be on the outlet side as
shown in FIG. 5. The magnet 426 moves in cooperation with the
orifice plate 428. The magnetic field created thereby will operate
a trouble Reed switch 156 when it becomes in a close enough
proximity thereto, and subsequently a fire Reed switch 158 as it
continues to move backwardly. By the time the magnet 426 approaches
the fire Reed switch 158 close enough to activate it, it has
cleared the bullet rod 420, and water is flowing through the bypass
means.
[0105] Normally, open Reed switches complete a circuit to send a
signal as they are activated. The trouble Reed switch 156
preferably activates an alarm, which only sounds in the structure
where the system is located. This alerts the residents that the
water usage is approaching the fire protection level, and that if
they want to avoid a fire alarm they need to reduce their water
usage. The fire Reed switch 158 preferably activates a system with
remote notification. That is, when the fire Reed switch 158 is
activated, a call is made to a fire department or other monitoring
authority, so that they can respond to the fire condition which has
apparently been created in the structure. The flow required to
activate the fire Reed switch 158 should not occur except in
circumstances where a fire sprinkler has activated in response to a
fire. The Parent Applications discuss the different flow regimes
between typical domestic uses and flow regimes required for fire
protection. It is important to calibrate the location of the Reed
switches, which can slide either toward the outlet or away from the
outlet by loosening the Reed switch clips 438. The calibration of
this system is described in the Parent Applications.
[0106] A passive pump 124 only operates when water flows to the
multi-purpose pipe section 120. Since this is a multi-purpose pipe
section, water will flow through the multi-purpose pipe section 120
on a regular basis to supply, for example, shower heads 122 or
faucets 134. In addition, where a pump 144 is provided to maintain
re-circulation to maintain a minimum temperature, the pump 144 will
also provide flow through the multi-purpose pipe section 120. When
there is flow through the multi-purpose pipe section 120 there will
be velocity head associated therewith. The passive pump 124 takes
advantage of this velocity head. As water passes into the chamber
202, a differential pressure is created by the configuration of the
inlet 204 and the outlet 206 such that water is drawn into the
inlet 204 and pulled out of the outlet opening 212. A vacuum of
sort is created by facing the outlet opening 212 away from the
inlet 204. Thus, the velocity head is used to create a flow through
the supply and return lines, 130 and 132, respectively.
[0107] However, when a fire sprinkler head 128 activates, the water
demand will be so great that water will be supplied to the head
fitting through both the head supply and head return lines 130 and
132, respectively. That is, both lines operate as supply lines when
a fire sprinkler operates. It has the advantage of allowing small
supply lines to be used than would be required if only one line
were in place. In addition, there is a redundancy because even if a
plug were to develop in one of the lines, the other line would
probably not be plugged and would still provide water to the
sprinkler head.
[0108] The operation of the return leg flow sensor 154 will be
illustrated with reference to FIGS. 1 and 5. In many respects, the
return leg flow sensor 154 is like the flow sensor 101. However, it
does not have the inlet or outlet ports for devices such as water
softeners nor need to have an alarm output. The only purpose of the
return leg flow sensor 154 is to allow flow there through when the
differential pressure from the inlet 504 to the outlet 506
increases to an extent indicating that additional water flow needs
to be allowed. Again, when the differential pressure rises to that
level, the orifice plate 524 is displaced to pass the end of the
bullet rod 512 allowing flow through the orifice 600. Internally,
the flow sensor 101 is attached both to the first pipe section 108
and to the tail end of the multi-purpose pipe section 120. It is
conceivable that where there are multiple sprinkler heads attached
to the multi-purpose pipe section 120, during a fire, there may
less than sufficient water to feed the sprinkler heads toward the
end of the multi-purpose pipe section 120. Therefore, additional
water would be allowed to pass through the return leg flow sensor
154 feeding these sprinklers at or near the end of the
multi-purpose pipe section 120. This additional water supply would
assist these sprinklers in doing their job of suppressing a
fire.
[0109] The double check valve in operation generally operates like
the flow sensor shown in either FIG. 4 or FIG. 5. However, it has
the added feature of the moving check, as well as o-rings disposed
on the moving orifice plate for sealing engagement with the bullet
port. The flow passes through the double check flow sensor 1100 in
the desired direction, that is, entering the main inlet port 1106
and passing out the main outlet port 1108 and passing therethrough,
the check valves are not activated. However, where there is a
pressure gradient which would force flow from the main outlet port
1108 backwards through the main inlet port 1106, the orifice plate
1130 is biased, both by the pressure gradient and by the check
spring 1124 towards the inlet port 1106. This causes the outer
orifice o-ring 1132 and the inner orifice o-ring 1134 to sealingly
seat against the outer seat 1804 and inner seat 1806 of the bullet
port 1112. Similarly, both the check spring 1124 and the pressuring
gradient bias the moving check 1118 towards the inlet port 1106.
Thus, the check o-ring 1120 sealingly seats against the check
shoulder seat 1136. Thus, the flow sensor having all of the
characteristics of the flow sensors shown in FIGS. 4 and 5 is
provided, but having the additional benefit of serving as a double
check valve. The operation of the double check flow sensor shown in
FIG. 21 is the same. However, the flow sensor shown in FIG. 21
incorporates a combination orifice plate/magnet 2130 for fewer
parts and lower cost.
[0110] While the invention has been shown, illustrated, described
and disclosed in terms of specific embodiments or modifications,
the scope of the invention should not be deemed to be limited by
the precise embodiment or modification therein shown, illustrated,
described or disclosed. Such other embodiments or modifications are
intended to be reserved especially as they fall within the scope of
the claims herein appended.
* * * * *