A system for insuring proper human hydration comprises an oral-suction-activated
flow meter (202) which measures and displays (292) the volume of
fluid (255) withdrawn from a reservoir (258) through tubing (270).
An optional check valve (280) prevents return flow of fluid (255)
from the user's mouth (205) to the reservoir (258). Mode and control
buttons (294) control operation of a microprocessor (300) and a
display (292). Both alphanumeric (292) and graphical (730 850)
displays show the volume withdrawn as a function of time or other
events. Drink reminder alarms are provided through a display (292)
or loudspeaker (520) to alert the user when it is time for a drink
to ensure proper hydration.
1. A method of enabling the monitoring and controlling of either
an individual's or an animal's proper hydration, comprising:
providing a liquid consumption meter for indicating the cumulative
quantity of liquid passing through said meter, said meter having
proximal and distal open ends for discharging and receiving liquid,
communicating said proximal open end with a user and said distal
open end with a liquid in a liquid reservoir carried with said user,
imbibing a quantity of said liquid at arbitrary times within a
predetermined time period by said user from said proximal end of
said consumption meter from said reservoir through said consumption
meter so that said consumption meter indicates a cumulative value
of said quantities of liquid consumed by said user, and
monitoring said cumulative value of said liquid over said predetermined
time period by said user so that proper hydration is insured.
2. The method of claim 1 wherein said consumption meter is integral
with said reservoir.
3. The method of claim 1 wherein said consumption meter has a digital
4. The method of claim 1 further including a tube connecting said
distal end of said consumption meter to said reservoir.
5. The method of claim 1 wherein said proximal end of said consumption
meter comprises a suction tube.
6. The method of claim 1 further including a tube for connecting
said distal end of said consumption meter to said reservoir, and
wherein said proximal end of said consumption meter comprises a
7. The method of claim 1 wherein said consumption meter further
provides a sensible indication when the quantity of liquid imbibed
by said user within a predetermined time interval fails to reach
a predetermined value, whereby a user will be reminded to consume
an adequate quantity of liquid.
8. The device of claim 7 wherein said sensible indication is an
audible alarm, whereby said user will be audibly alerted when said
user has not imbibed said predetermined value of said adequate quantity
of liquid within said predetermined time interval.
9. A liquid-consumption device for enabling the monitoring and
controlling of either an individual's or an animal's proper hydration
a portable liquid reservoir for holding a quantity of liquid, said
reservoir being carried by a user,
a liquid consumption meter having a passage therethrough for indicating
a quantity of liquid each time said liquid moves through said passage,
said reservoir including means for transferring liquid from said
reservoir via said passage in said meter into said user, such that
the cumulative quantity of liquid imbibed by said user from said
reservoir being indicated by said meter to thereby insure proper
10. The device of claim 9 wherein said means comprises a tube for
communicating said meter with said user.
11. The device of claim 9 wherein said means comprises a first
tube for communicating said meter with said user and a second tube
for connecting said reservoir to said meter.
12. The device of claim 9 wherein said consumption meter is integral
with said reservoir.
13. The device of claim 9 wherein said consumption meter has a
digital readout for indicating a quantity of liquid consumed.
14. The device of claim 9 wherein said consumption meter includes
a plurality of vanes rotatably responsive to the flow of liquid
therethrough, and means for counting the number of rotations of
15. The device of claim 14 wherein said means for counting comprises
a magnet arranged to move with said vanes and a coil positioned
to generate pulses in response to rotation of said magnet.
16. The device of claim 9 wherein said consumption meter has a
mechanical component responsive to the flow of liquid therethrough
for providing an electrical output indicative of the amount of liquid
flowing therethrough, and an electrical component responsive to
said electrical output for indicating the quantity of liquid flow
17. The device of claim 16 wherein said mechanical component and
said electronic component are integral.
18. The device of claim 9 wherein said consumption meter provides
a sensible indication when the quantity of liquid imbibed by said
user within a predetermined time interval fails to reach a predetermined
value, whereby a user will be reminded to consume an adequate quantity
of liquid within said predetermined time interval.
19. The device of claim 18 wherein said sensible indication is
an audible alarm, whereby said user will be audibly alerted when
said user has not imbibed said adequate quantity of liquid.
1. Field of Invention
This invention relates to the measurement of liquid flow, particularly
to metering fluid intake for proper human hydration.
2. Prior-Art--Hydration Systems
Physicians generally agree that for optimum health and proper nutrition,
each person should drink at least eight 240 ml (8-oz) glasses of
water a day under normal conditions. This is because fluids are
continually lost from the body at varying rates throughout the day,
the rate of loss increasing during exertion. Serious consequences
result if this water is not replaced in the proper amount and at
the proper time. These consequences include fatigue, nausea, loss
of consciousness, and, potentially, death. This problem is compounded
because thirst is not a reliable indicator of the need for hydration
(water); one can be in severe need of hydration, yet not feel thirsty.
In all athletic endeavors, it is vital to maintain a proper level
of hydration in one's body. It is well-known that proper body hydration
is essential before, during, and after strenuous exercise. See,
for example, "Exercise and Fluid Replacement", V. A. Convertino,
et al., Medicine and Science in Sports and Exercise, Vol. 28 No.
1 pages i-vii, 1996. While ad libitum fluid ingestion is useful,
and even required, it does not generally provide sufficient hydration.
A survey of 3003 Americans, released on May 11 1998 by the Nutrition
Information Center at The New York Hospital-Cornell Medical Center
and the International Bottled Water Association, found that most
Americans are probably only getting about a third of the valuable
hydration benefits they need." says Barbara Levin, R. D., Ph.D.,
director of the Center. "The vast majority aren't drinking
enough water to begin with, and, to make matters worse, many don't
realize that beverages containing alcohol and caffeine actually
rob the body of water."
In hospitals it is frequently vital to maintain the rate of hydration
of a patient. In some cases the rate of hydration is partially known
by the rate of delivery of intravenously supplied fluids. According
to the study, "Intravenous vs. Oral Rehydration: Effects on
Subsequent Exercise-Heat Stress", J. Appl. Physiol. 82(3):
799-806 1997 research suggests that after exercise-induced dehydration,
intravenous and oral deliveries were equally effective as rehydration
treatments. However, intravenous delivery of fluids is invasive
and subject to complications. Intravenous delivery is also not a
practical means for preventative hydration. In the past, the patient's
total oral consumption of fluid has been monitored and maintained
by guesswork. Patient care is often deficient, however, because
there is no accurate measure of the patient's rate or quantity of
hydration. This results in patient upsets and increases time and
effort required by the medical staff.
According to the March, 1994 issue of the Canadian Medical Journal,
studies have shown that an increase in water intake can actually
reduce fat deposits. Drinking enough water is the best treatment
for water retention. Since water is the key to fat metabolism, it
follows that the overweight person needs to drink more water. Although,
as stated, on the average, a person should drink eight eight-ounce
glasses every day, the overweight person needs one additional glass
for every 25 pounds of excess weight.
According to the Journal of the American Dietetic Association,
Vol. 99 No. 2 February, 1999 in the article titled: "Water:
An Essential but Overlooked Nutrient", "New research indicates
that fluid consumption in general and water consumption in particular
can have an effect on the risk of urinary stone disease; cancers
of the breast, colon, and urinary tract; childhood and adolescent
obesity; mitral valve prolapse; salivary gland function; and overall
health in the elderly. Dietitians should be encouraged to promote
and monitor fluid and water intake among all of their clients and
patients through education and to help them design a fluid intake
Various liquid containers for supplying drinking water are commercially
available. They range from a simple bottle to a sports-oriented
backpack reservoir with a delivery tube. Several models of a backpack
reservoir system are sold by FasTrak Systems, Inc., P O Box 1029
Weatherford, Tex. 76086-1029 under the mark CamelBak. The HydroBak.TM.
model comprises an insulated fluid reservoir which holds 1.5 liters
(50 oz). After filling, the reservoir is placed in a sack-like container.
A pair of straps holds the sack against the user's back. In an alternative
design, the reservoir is strapped to a waist-pack on the user's
waist in a similar fashion. A flexible tube, of length approximately
38 cm (15 in), and diameter of approximately 0.95 cm (3/8 in) connects
to the reservoir. A valve-mouthpiece is secured to the distal end
of the tube. Some prior-art valves are opened by a biting action;
others are opened by forcing the valve open with the user's mouth
parts. To obtain water (or another fluid) from the reservoir, the
user simply opens the valve and creates a suction with her or his
mouth. In response to this suction, fluid leaves the reservoir and
is delivered to the user's mouth for swallowing. This system provides
ad-libitum hydration only. It does not accurately indicate the volume
of fluid consumed, or the rate at which the fluid has been consumed.
Nor does it provide a reminder for users who may be dehydrated but
A similar sport hydration system is taught by Boxer et al. in U.S.
Pat. No. 4526298 (1985). In this system, the user wears a back-mounted,
liquid-filled reservoir. A flexible tube, similar to the above,
connects the reservoir to a hand-held, hand-operated pump. When
the pump handle is squeezed, the pump delivers either a stream or
a spray of water, depending upon the adjustment of a nozzle attached
to the pump's output orifice. The user can thus spray a stream of
liquid into her or his mouth to be swallowed, or optionally douse
her or his face or other body areas with a cooling mist.
Operation of Boxer's pump handle requires the user to have one
band free. This is not always possible when the user is riding a
bicycle, climbing a mountain, or skiing. More importantly, although
the spray produces a feeling of comfort, it does not contribute
to the user's level of hydration. Further, Boxer's system does not
measure the volume of fluid delivered over a predetermined period
of time. While dousing one's body with a cooling mist may feel good,
it does nothing to maintain proper hydration.
A liquid dispenser meter is taught by Griffiths et al., in U.S.
Pat. No. 4350265 (1982). This meter is mounted on a bottle which
contains an alcoholic beverage. To dispense the alcohol, the bottle
is inverted, causing the alcohol to fill a measuring chamber. Pressing
on a plunger causes (a) a predetermined volume of liquid in the
chamber to be dispensed, and (b) a counter to be advanced by one
count. Thus by knowing the volume dispensed each time the plunger
is pushed, and the volume of liquid in the measuring chamber, the
total volume of liquid dispensed through the meter is known. While
it provides information about liquid volume dispensed, this system
does not display the volume dispensed as a function of time. Further,
the bottle must be inverted in order to dispense liquid, the flow
being urged by gravity. A user such as a bicyclist would not use
this system because it dispenses an alcoholic beverage, which, as
stated, actually decreases hydration. Also the bicyclist cannot
conveniently get water from the inverted bottle and cannot use oral
suction to dispense liquid from the bottle. The rate of consumption
is not indicated and there is nothing to remind the user to drink.
Thus, even if this system could be used by inverting the bottle,
Griffiths' system provides only ad-libitum consumption of liquids
and cannot ensure that the user maintains proper hydration.
Sigdell et al., in U.S. Pat. No. 3919455 (1975) teach an apparatus
which measures the volume and flow rate of liquids. This system
uses a siphon-suction principle in which a container is filled by
suction, then when a predetermined level is reached, a siphon causes
the container to drain. Electrical sensors detect the evacuation
of the container and signal that the container is ready for another
fill-and-drain cycle. While this system provides information about
liquid volume dispensed, it does not display the volume dispensed
as a function of time. Further, suction is used only to fill the
chamber. If the siphon action is not allowed, the chamber will not
drain and the chamber will remain full. Even if repeated siphon
and suction cycles were employed, this system would not be practical
in human hydration applications. The entire contents of the container
are drained in each siphon cycle. Thus, the user would be required
to swallow the entire volume of the container. Because of the container's
fixed size, it would not be possible for the user to withdraw a
single sip of liquid at one time, and at a later time withdraw a
mouth-full from the same container. Because of these limitations,
this system is not applicable to maintenance of hydration.
None of the prior-art fluid supply systems accurately reports the
rate of fluid consumption. Further, none of the prior-art fluid
supply systems indicates, in advance of the user's thirst, that
it is time to consume more fluid. By the time a user is thirsty,
she or he is already partially dehydrated.
3. Prior-Art--Flow Meters
Many prior-art liquid flow meters are known. In general, they comprise
the following types: differential pressure, positive displacement,
velocity, and mass meters. In differential pressure meters, flow
is inferred from the pressure differential which arises from flow
in a predetermined geometry. These include orifice, Pitot, venturi,
and other well-known types. In positive displacement meters, flow
is related to the movement of a member within the meter. These include
rotary vane, gear, and piston types, among others. Velocity types
measure the velocity of the liquid through a region of known cross-section.
These include turbine, sonic, and ultrasonic types, among others.
Mass flow types measure the actual passage of mass through the meter.
These include thermal, optical, coriolis, and other types.
U.S. Pat. No. 4489616 (1984) to Priddy teaches a "Digital
Fluid Flow Meter". In this meter, fluid impinges on the vanes
of a rotary impeller, forcing it to turn. FIG. 1 shows the principal
elements of this meter. Liquid enters the meter through external
connection 32. It flows through channel 34 and exits into the chamber
bounded by circular opening 18. The fluid flow impinges on radial
vanes 26 of impeller assembly 20 which is free to rotate on bearings
(not shown). Fluid fills the spaces 28 between vanes 26. Fluid leaves
the region surrounding the impeller through an outflow channel (not
shown) along flow lines 54. The fluid finally exits the flow meter
through orifice 50 and exit fitting 52. The rate of rotation of
impeller 20 is proportional to the rate of flow of the fluid passing
through the meter. The driving force for fluid motion is generally
derived from elevated pressure applied to the fluid entering at
A magnet 60 is secured in one of the vanes 26 of impeller 20. An
external coil is placed in the vicinity of the impeller. As the
impeller turns, the motion of the magnet induces a voltage in the
coil. This voltage creates a current generally in the form of transient
pulses which have a rising edge as the magnet approaches the coil,
and a falling edge as the magnet retreats. These pulses are counted
using conventional digital electronic circuitry. The pulse rate
frequency is equal to the rate of rotation of impeller 20 and thus
is directly proportional to the rate of flow of liquid through the
meter assembly. With appropriately tight tolerances, Priddy's meter
can be made to approximate a positive displacement flow meter.
While Priddy can accurately measure flow volume and rate, his system
does not solve the aforementioned hydration problems.
OBJECTS AND ADVANTAGES
Accordingly, several objects and advantages of the present invention
are to provide a method and apparatus to accurately meter and report
the rate of consumption of fluids. A further object is to provide
a display which indicates to the user when it is time to consume
fluid, in advance of the user's thirst craving. Another object is
to provide a fluid metering, reporting, and alarming system which
is compact, inexpensive, rugged, portable, orally activated, and
simple to use and understand. Still another object is to provide
a fluid metering system which enhances both normal and athletic
performance and protects health, promotes patient compliance, and
ensures proper maintenance of body hydration.
Additional objects and advantages will become apparent from a consideration
of the drawings and ensuing descriptions thereof.
In accordance with the present invention, a fluid measurement system
and method uses a flow meter to measure volume and volume rate of
fluid flow obtained by the user through oral suction. Standard fluid
reservoirs and tubing are used in novel combination with a flow
meter which maintains a record of fluid that the user has drawn
into the mouth. The flow meter optionally provides auditory, visual,
or tactile stimuli to signal the user to sip fluids at predetermined
or calculated times. Through proper management of fluid dispensation,
the user experiences increased athletic performance, and improved
maintenance of health.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a prior-art flow meter.
FIG. 2 shows the preferred embodiment of a flow meter hydration
system according to the present invention.
FIG. 3 is a block diagram showing the principal components of a
preferred embodiment of the system.
FIGS. 4A and 4B are two views of the flow sensor component of the
FIG. 5 is an electronic schematic diagram of the preferred embodiment.
FIGS. 6A through 6G are flow charts showing operation of the preferred
FIG. 7 shows the preferred embodiment inserted in line with a drinking
FIGS. 8A and 8B show the preferred embodiment incorporated with
a drinking bottle.
FIG. 9 shows the preferred embodiment in use with a backpack or
FIG. 10 shows the preferred embodiment with the flow sensor attached
to the electronics section.
FIG. 11 shows the preferred embodiment with the flow sensor detached
from the electronics section.
FIGS. 12A through 12D are four graphical presentations according
to the present invention.
DRAWING FIGURE REFERENCE NUMERALS
18 Circular opening
26 Radial vanes
32 External connection
52 Exit fitting
54 Flow lines
200 Oral suction
202 Flow meter and indicator
240 Exit tube
250 Flow metering device or transducer
270 Entrance tube
285 Alternative check-valve position
290 Display and Control Unit
294 Control buttons
202 Preferred embodiment
250 Flow transducer
290 Display and Control Unit
294 Function controls
300 Microprocessor control unit
FIGS. 4A and 4B
400 Impeller assembly
410 Angled vanes
470 Bearing mounts
500 Magnetic field lines
560 Power source
FIGS. 6A through 6G
202 Flow meter assembly
551 Recessed switch
710 Drinking straw
FIGS. 8A and 8B
202 Flow meter assembly
250 Flow transducer
290 Display and control unit
830 Optional tube
850 Bar graph
202 Flow meter
FIGS. 10 and 11
250 Flow transducer
280 Optional check valve
FIGS. 12A through 12D
1205 Consumption rate goal line
1215 Fluid consumption vs. time
1218 Volume goal line
1230 Volume remaining vs. time
1240 Bar chart
1250 Fluid consumed
1245 Fluid remaining
1260 Pie chart
1270 Fluid consumed
1265 Fluid remaining
PREFERRED EMBODIMENT--FIG. 2--Description
FIG. 2 is a block diagram showing the various components of a flow
meter hydration system of the present invention, in use by a user
205. The main components or elements of FIG. 2 are a suction-activated
flow meter and indicator 202 a water or liquid reservoir 258 and
tubings 220 and 270 to connect the reservoir to the meter and the
meter to the user.
Specially, suction indicated by arrow 200 is provided within the
mouth of user 205. The user's lips 210 form a tight seal around
tubing 220 which is attached to hollow barbed fitting 230. Although
a barbed fitting is shown, fitting 230 can be a friction-fit fitting,
a glued junction, or other suitable attachment method. Fitting 230
communicates with exit tube 240 of meter and indicator 202.
In meter and indicator 202 is a flow metering device or "transducer"
250. Device 250 may be similar to that of Priddy, described above
and shown in FIG. 1 or it may be of the type described in more
detail below. In any case, a positive-displacement-type flow metering
device is desirable.
Fluid 255 from external reservoir 258 which is a container such
as a bottle or bladder, enters hollow barbed fitting 260 at the
input of meter and indicator 202 and flows to metering device 250
through entrance tube 270. From there, it flows through exit tube
240 barbed fitting 230 and tubing 220 to the user's mouth.
An optional, one-way check valve 280 is shown in exit tube 240.
Valve 280 permits the flow of fluids in one direction only, in this
case from right-to-left. This action prevents return flow of the
fluid into the container. Such reverse flow can result in an incorrect
volume reading if it is not taken into account. Reverse flow will
result in reverse rotation of impeller assembly 400 (FIG. 4). If
check valve 280 is not used, a means for detecting and counting
reverse rotation, well-known to those skilled in the art of fluid
flow measurement, may be used. The reverse fluid volume can be subtracted
from the total measured volume.
Valve 280 also helps prevent contaminants in the user's mouth from
entering the flow metering device 250 or fluid reservoir 258. An
alternative check valve position is shown at 285.
Display and control unit 290 contains means for detecting and analyzing
the flow of fluid 255 through metering device 250. Display 292 provides
alphanumeric indications of flow rates, time, alarms, and the like.
It can also provide graphical indications such as fluid consumed
vs. time, and the like. Control buttons 294 enable setting of the
internal operating parameters of unit 290. Unit 290 can optionally
emit visible, audible, or tactile signals which can be perceived
by the user. This is discussed in greater detail below.
The preferred embodiment of meter and indicator 202 can be very
compact. A realistic size is 4 cm wide, 2 cm high, and 1 cm deep.
Block Diagram--FIG. 3
Meter and indicator assembly 202 is shown in block diagram form
in FIG. 3. Display and control unit 290 preferably comprises a microprocessor
control unit 300 one or more function controls 294 and display
292. The output of flow transducer 250 is connected to microprocessor
control unit 300. The entire system is typically powered by a known
battery or other power source (not shown).
Microprocessor 300 may be of the type PIC15C924PLCC, manufactured
by Microchip Corporation, 2355 W. Chandler Blvd, Chandler, Ariz.
85224 USA. Display 292 generally comprises an alphanumeric display
of the type LCD-4312 manufactured by Lumex, Inc., 290 E Helen Rd.,
Palatine, Ill. 60067 USA. It may also comprise an audio transducer
of the type EFB-AA14D001 manufactured by Matsushita Electric Corporation
of Japan under the mark Panasonic-ECG, or a tactile stimulator such
as those manufactured by Telesensory Corporation, 520 Almanor Ave.,
Sunnyvale, Calif. 94086 USA.
Flow Sensor--FIG. 4
Flow metering device 250 (FIG. 2) comprises an impeller assembly
or turbine 400 (FIG. 4A) with four angled vanes or blades 410 terminating
in a supporting ring 401. Ring 401 is a solid annulus and is attached
to the outer ends of vanes 410 so that it rotates with the vanes.
It has a thickness (radial) of about 1 mm and a length (from left
to right in FIG. 4B) of about 0.5 cm. A magnet 490 is mounted in
a hole in ring 401 parallel to the axis of shaft 430 with north
and south poles at the distal ends, as indicated in FIG. 4B. A coil
510 is mounted on the outside of housing 480. The axis of coil 510
is also parallel to the axis of shaft 430. The orientation of magnet
490 can be reversed, if desired, with the only effect being a reversal
of the polarity of the pulse created in coil 510 i.e., negative-then-positive
vs. positive-then-negative. Either polarity can be counted by microprocessor
300 (FIG. 3). Magnet 490 is typically a cylindrical bar magnet,
with diameter and length of 0.5 mm and 1.5 mm, respectively. If
necessary, magnet 490 can be counterbalanced by a second magnet,
or a non-magnetic weight located in a hole at the opposite side
of ring 401. Coil 510 is located in display and control unit 290
(FIG. 2). Wires 494 connect coil 510 to microprocessor 300 (FIG.
5). Impeller assembly 400 (FIG. 4) is mounted on a shaft 430. Journals
440 at the ends of shaft 430 insert into simple bearings 450. Bearings
450 comprise holes 460 in bearing mounts 470 which are secured
to housing 480. The diameter of holes 460 is only slightly larger
than that of journals 440. Thus impeller assembly 400 is free to
rotate within housing 480 while otherwise positionally constrained
by holes 460 in mounts 470. The diameter of impeller assembly 400
is preferably about one centimeter (0.5 in). Other components shown
in FIGS. 4A and 4B are roughly to scale with respect to one-another.
The diameter of journals 440 is typically 0.75 mm (0.03 in), and
the axial length of impeller assembly is approximately 0.5 cm (0.25
in). Housing 480 is preferably made of a durable plastic such as
polycarbonate. Alternatively, it can be made of a non-metallic metal
such as aluminum. Ring 401 and vanes 410 are preferably made of
polycarbonate or polyester or another rigid plastic material. Shaft
430 and bearing mounts 470 are preferably made of stainless steel,
although in some applications a rigid plastic material such as polycarbonate
or polyester may be used.
Flow Meter Assembly Circuit Diagram--FIG. 5
A schematic circuit diagram of one preferred embodiment is shown
in FIG. 5. The proximity of magnet 490 is detected as it moves past
coil 510 (FIG. 4). At position 1 the coil output voltage is a positive-going
peak as the magnet approaches the coil. At position 2 the sensor
output voltage is zero when the magnet is at the middle of the coil.
At position 3 the sensor output voltage is a negative-going peak
when the magnet leaves the coil. When a single magnet 490 is used,
each zero-positive-negative-zero transition, or pulse, is counted
by microprocessor 300 as one rotation of impeller assembly 400.
If a second magnet is used, each pulse is counted as one-half rotation
of impeller assembly 400.
During a typical suction-induced flow of fluid through flow sensor
250 (FIG. 2), impeller assembly 400 rotates at a rate of 10 revolutions
per second (RPS). Since one magnet is used in this embodiment, the
frequency of the output voltage pulses of coil 510 is 10 Hz. More
suction increases this frequency; less decreases it. The volume
consumed is proportional to the number of pulses. Thus the total
volume consumed is determined by counting the number of pulses and
storing this count in the memory of microprocessor 300. The rate
of consumption is determined by dividing the volume consumed by
a convenient time period, preferably one hour, although another
time period can be used. An algorithm (formula) which determines
the volume and rate of consumption is described below in connection
with FIG. 6G.
If desired, the volume consumed in each sip can be measured using
another algorithm which counts groups of pulses which are separated
by periods of no pulse activity. The volume of each sip is thus
proportional to the number of pulses in the group representative
of that sip.
Loudspeaker or another type of audio transducer, e.g., a piezoelectric
disc, 520 is driven by microprocessor 300 and is used to alert the
user to various alarm conditions, such as low reservoir, drink reminder,
and time alarm.
Switches 530 540 and 550 are used to set various internal parameters
and to select among various modes of operation. For example, pressing
mode switch 550 grounds the mode terminal of microprocessor 300
which causes microprocessor 300 to enter various modes of operation
which are programmed into its memory. The various modes are described
below in connection with FIG. 6B.
The system can reset individual functions through use of mode switch
550. An additional reset switch can be located in an accessible
but less prominent area of the device for complete reset of all
functions, including the real time clock.
Momentary closing of master reset switch 551 resets all functions
and initializes all counters contained in microprocessor 300 as
described below in connection with (block 603) of FIG. 6A. Switch
551 is typically recessed in the body of electronics assembly 202
(FIG. 7) to prevent accidental actuation. It may be actuated by
the tip of a pencil, for example.
Operation of the Preferred Embodiment--FIGS. 4-11
In response to suction 200 (FIG. 2) in mouth of user 205 fluid
255 flows axially through metering device 250. Fluid impinging on
angled vanes 410 causes impeller assembly 400 to turn. As impeller
assembly 400 turns, magnet 490 mounted near the perimeter of impeller
assembly 400 in ring 401 creates a periodically changing magnetic
field near the outside surface of housing 480 which is made of
a non-magnetic material.
The rate of rotation of impeller assembly 400 is determined by
the rate of flow of fluid 255. The number of rotations of impeller
assembly 400 is thus proportional to the volume of fluid 255 which
flows through it. Careful design of impeller assembly 400 vanes
410 housing 480 journals 440 and bearing mounts 470 in accordance
with well-known techniques in the fluid metering art, results in
a metering device which is accurate for a wide range of flow rates.
Magnetic field lines 500 (FIG. 4B) from magnet 490 are shown extending
outside housing 480. At any given location on housing 480 magnetic
field 500 varies in strength as impeller assembly 400 turns and
magnet 490 approaches then retreats from that location. These variations
are detected by coil 510 located on the outer surface of housing
480. As magnet 490 moves in the vicinity of coil 510 a current
is induced in coil 510 in well-known fashion. Wires 494 connect
coil 510 to microprocessor 300 as shown in FIG. 5.
In the present embodiment, there is one magnet 490 in ring 401
of impeller assembly 400. Thus with each rotation of impeller assembly
400 sensor 510 will see one rise and one fall in magnetic field
strength, as shown by the waveform above microprocessor 300. The
output of coil 510 thus experiences one positive-going pulse and
one negative-going pulse with each rotation of impeller assembly
400. The resultant waveform is shown in FIG. 5. In lieu of a single
magnet, two, three, or four magnets can be mounted in symmetrical
positions around ring 401. In lieu of ring 401 vanes 410 can be
extended to the position of the outer radius of ring 401. In this
case, magnet 490 or multiple magnets can be mounted in or on one
or more of vanes 410.
Flow Charts--FIGS. 6A through 6G
These flow charts show the algorithmic steps required to calibrate
the monitoring system, select display graph styles, update displays,
detect switch closures, detect a sip, and determine the volume swallowed
by the user over a given period of time. If the volume consumed
in a given time period is not sufficient, an audible alarm is sounded.
FIG. 6A--Reset Functions and Interrupt Handler
The above-mentioned algorithmic steps begin with start block 600
in FIG. 6A. When power is first applied to microprocessor 300 (FIG.
5), a program sequence (not shown) performs a well-known "power-up
reset" (block 601). This function resets and initializes all
counters and various functions, including a real-time clock (block
602) which is contained in microprocessor 300.
Further programming in block 603 contained in the memory (not
shown) of microprocessor 300 resets all the functions and values
used in the instant system. After the system is reset, microprocessor
300 waits (block 604) for an "interrupt", well-known in
the art of programming.
Switch closures and flow pulses are detected as "interrupts"
by the internal circuitry of microprocessor 300. The algorithms
which are used to interpret interrupts are referred to as "interrupt
handlers". This concept is well-known to those skilled in the
arts of computer and microprocessor programming. When a pulse is
detected in coil 510 (FIG. 5), or one of switches 530 540 550
551 is closed, microprocessor 300 detects an interrupt.
When an interrupt is detected, microprocessor 300 determines the
source of the interrupt. If closure of reset switch 551 is detected
(block 605), the interrupt handler program returns program execution
to the top of block 603 resetting all user functions and setting
a mode "pointer", described below, to its first position,
a reset function. Pointers are well-known to those skilled in the
art of computer programming. When a pointer is set to a location
in a computer program, execution of the program continues from that
If a button switch (530 540 or 550 in FIG. 5) closure is detected
(block 606), then the algorithm branches to the switch routines
in FIGS. 6B through 6F (block 607).
If a fluid flow pulse is detected (block 608), then the algorithm
branches to the flow routines in FIG. 6G, block 609.
FIGS. 6B through 6F--Switch Routines
The switch routines begin at block 610. If plus switch 530 or minus
switch 540 is pressed at this point in the program, this closure
is ignored since its purpose is indeterminate.
Reset All--FIG. 6B
If either plus switch 530 or minus switch 540 is pressed at this
point in the program the desired action would be unknown; therefore
no action is taken (block 612).
If mode switch 550 is pressed (block 611), then display 292 (FIG.
2) shows the text: "Reset All?", block 613. At this point,
the user can accept or reject this command. If the user presses
plus switch 530 then program control returns to block 603 (FIG.
6A), resetting all functions, except the time of day, and setting
the mode pointer to the reset function.
If the user presses minus switch 540 (block 616), indicating a
negative response, no action is taken (block 617) and program control
continues to block 618.
If mode switch 550 is pressed a second time (block 618), then program
control advances to the next mode of operation (block 619).
If no switch is pressed, then a timeout function (block 620) is
initiated. The program waits a predetermined amount of time, typically
5 seconds. Then display 292 redisplays the most recent data and
program control returns to block 604 (FIG. 6A), and waits for another
Select Units--FIG. 6B
Display 292 now shows the text "Select Units" (block
622). If plus switch 530 is pressed (block 623), all volumetric
units subsequently shown on display 292 will be displayed as English
units, i.e., ounces and quarts (block 624). English units will be
shown in all data shown in display 292 (block 624) until another
selection is made. Upon receiving the command "Reset All"
(block 603), English units are the default choice. Alternatively,
the default choice can be metric.
If minus switch 540 is pressed instead (block 625), then metric
units, i.e. milliliters and liters, will be displayed (block 626).
If mode switch 550 is pressed (block 627), then in block 628 the
program saves a parameter in the memory of microprocessor 300 which
represents the current English or metric selection and advances
to the next function, "Enter Reservoir Volume".
If no switch is pressed, then the timeout function (block 629)
is initiated and in block 630 program control saves the current
selection and returns to block 604 as above.
Enter Reservoir Volume--FIG. 6C
Display 292 now shows the text "Enter Reservoir Volume, 60
ounces", assuming English units are selected (block 631). Alternatively,
the word "Enter" or "Enter Reservoir Volume"
can be omitted and display 292 can read "Res. Vol.: 60 oz"
or "VB 60 oz" or just "60 oz". If metric units
were selected the display would instead show "Enter Reservoir
Volume, 1.77 liters". The foregoing volumes contained in the
program of microprocessor 300 are default values. Default values
assist the user in setting the actual volume contained in the fluid
reservoir 258 (FIG. 2). Due to the small size of the display, suitable
abbreviations can be used for the foregoing and all other messages.
If plus switch 530 is pressed (block 632), the volume of fluid
in reservoir 258 is incremented (block 633) by a convenient amount,
preferably one ounce for each pressing of switch 530. After the
first pressing of switch 530 the text on display 292 reads: "Enter
Reservoir Volume, 61 ounces". After the second pressing, the
text on display 292 reads: "Enter Reservoir Volume, 62 ounces",
and so forth.
If minus switch 540 is pressed (block 634), then the volume of
fluid in reservoir 258 is decremented (block 635) and display 292
is updated accordingly.
If instead mode switch 550 is pressed again (block 636), then the
current reservoir volume value is stored in the memory of microprocessor
300 and program control advances to the next successive mode selection
If no switch is pressed, the timeout function (block 638) stores
the current reservoir volume value in the memory of microprocessor
300 and returns program control to block 604 as above (block 639).
Enter Consumption Rate Goal--FIG. 6C
Display 292 now shows the text "Enter Consumption Rate Goal,
8 Ounces/Hour", assuming, as above, that English units are
selected (block 640). The goal of 8 ounces per hour is stored in
the program of microprocessor 300 as a default value. If plus switch
530 is pressed (block 641), then the volume rate is incremented
(block 642) by a convenient amount, preferably one-half ounce for
each pressing of switch 530. After the first pressing of switch
530 the text on display 292 reads: "Enter Consumption Rate
Goal, 8.5 Ounces/Hour". After the second pressing of switch
530 the text on display 292 reads: "Enter Consumption Rate
Goal, 9.0 Ounces/Hour", and so forth.
If minus switch 540 is pressed (block 643), then the consumption
rate goal is decremented (block 644) and display 292 is updated
If instead mode switch 550 is pressed again (block 645), then the
current consumption rate value is saved in the memory of microprocessor
300 and program control advances to the next successive mode selection
If no switch is pressed, the timeout function (block 647) saves
the current consumption rate value in the memory of microprocessor
300 and returns program control to block 604 as above (block 648).
Enter Volume Goal--FIG. 6D
Display 292 now displays the text: "Enter Volume Goal, 64
Ounces" (block 649), again assuming that English units are
selected. The volume goal of 64 ounces is stored in the program
of microprocessor 300 as a default value. If plus switch 530 is
pressed (block 650), then the volume goal is incremented (block
651) by a convenient amount, such as one ounce for each pressing
of switch 530. After the first pressing of switch 530 the text
on display 292 reads: "Enter Volume Goal, 65 Ounces",
the second pressing causes the display to indicate 66 ounces, and
If minus switch 540 is pressed (block 652), then the volume goal
is decremented (block 653) and display 292 is updated accordingly.
If instead mode switch 550 is pressed again (block 654), then the
current volume goal value is stored in the memory of microprocessor
300 and program control advances to the next successive mode selection
If no switch is pressed, the timeout function (block 656) saves
the current volume goal value in the memory of microprocessor 300
and returns program control to block 604 as above (block 657).
Select Graph--FIG. 6E
Display 292 now displays the text: "Select Graph" (block
658). Multiple actuations of plus switch 530 (block 659) cause the
program to successively display volume consumed as a function of
time, volume remaining in reservoir 258 as a function of time, a
bar or pie chart showing total volume consumed, a bar or pie chart
showing total volume remaining in reservoir 258 and the like (block
Multiple actuations of minus switch 540 (block 661) cause the program
to successively display graph types in reverse order (block 662).
Thus if the user inadvertently presses switch 530 too many times,
he or she can return to a previously displayed graph type by pressing
If mode switch 550 is pressed (block 663), then the current graph
type is saved in the memory of microprocessor 300 and program control
proceeds to the next mode selection (block 664).
If no switch is pressed, the timeout function (block 665) saves
the current graph type in the memory of microprocessor control and
returns program control (block 666) to block 604 (FIG. 6A), as above.
Set Time of Day--FIG. 6E
Display 292 now displays the text: "Set Time of Day, 12:00
PM" (block 667). If plus switch 530 is pressed (block 668),
the time shown on display 292 is incremented from the presently
stored value and the internal time-of-day clock in microprocessor
300 is set to the new value (block 669). As above, the default value
12:00 PM is presented to the user after a system reset, such as
would occur when a battery is replaced or master reset switch 551
(FIG. 5) is momentarily closed.
If minus switch 540 is pressed (block 670), then the time of day
is decremented on display 292 and in the clock of microprocessor
300 (block 671).
If mode switch 550 is pressed (block 672), program control proceeds
to the next mode selection (block 674).
If no switch is pressed, the timeout function (block 675) returns
program control (block 676) to block 604 as above.
Audible Alarm--FIG. 6F
Display 292 (FIG. 2) now displays the text: "Audible Alarm
On" (block 677). If Plus switch 530 is pressed (block 678),
the audible alarm function which sounds through loudspeaker 520
(FIG. 5) is enabled (block 679).
If minus switch 540 is pressed (block 680), then the audible alarm
function is disabled (block 681).
If mode switch 550 is pressed (block 682), then the state of the
audible alarm function is saved in the memory of microprocessor
300 and program control proceeds to the next mode selection (block
If no switch is pressed, then the timeout function (block 684)
saves the state of the audible alarm function in the memory of microprocessor
300 and returns program control (block 685) to block 604 as above.
Begin Monitoring--FIG. 6F
Display 292 now displays the text: "Begin Monitoring"
(block 686). If plus switch 530 is pressed (block 687), then the
monitoring functions which have been established above, are enabled
(block 688) and revolutions of impeller assembly 400 will be counted
and fluid consumption monitored, as described below.
If minus switch 540 is pressed (block 689), then the monitoring
functions are disabled (block 690).
If mode switch 550 is pressed (block 691), then program control
proceeds to the next mode selection (block 692). In the absence
of further selectable modes, the next mode selection is "Reset
All" (block 613).
If no switch is pressed, then the timeout function (block 693)
returns program control (block 694) to block 604 (FIG. 6A), as above.
FIG. 6G--Flow Routines
When a flow pulse interrupt is detected by coil 510 and microprocessor
300 (FIG. 5), program control is directed (block 609--FIG. 6A) to
the flow routine (block 1600). Upon detection of a flow pulse (block
1602), the flow routine interrupt handler tests to see if monitoring
functions have been enabled (block 1604). If not, no action is taken
(block 1606) and microprocessor 300 waits for another interrupt
If monitoring functions are enabled (block 1604), then the program
memory location in microprocessor 300 which counts flow pulses is
incremented (block 1608). The newly-incremented value is multiplied
(block 1610) by a flow calibration factor which is stored in the
memory of microprocessor 300. The flow calibration factor is determined
at the time of manufacture of flow transducer 250 (FIG. 3).
The time interval since the most recent flow pulse and the present
flow pulse is determined (block 1612). The new increase in volume
determined above in block 1610 is divided by the current time interval
to yield the volume consumed in this time interval (block 1614).
The new volume is added to the existing volume in the memory of
microprocessor 300 (block 1616), along with the time of day (block
In block 1620 the volume consumed in the current time interval
is compared with the consumption rate set by the user (block 640--FIG.
6C). If this rate is greater than or equal to the pre-set rate (volume/time),
then no alarm action is taken (block 1622).
If, however, the rate of consumption is less than the pre-set rate
(block 1620) and the audible alarm function is enabled (block 1624),
then an audible alarm is activated (block 1628). If the audible
alarm function is disabled, then no alarm action is taken (block
If the volume consumed display is selected (block 1630), then the
volume consumed is calculated in either English or metric units
(block 1632) and displayed on display 292 in either graphical or
numeric form (block 1634).
If the volume remaining display is selected (block 1636), then
the volume remaining is calculated by subtracting the volume consumed
(block 1632) from the reservoir volume (blocks 633 and 635--FIG.
6C). The English or metric equivalent of this value is then calculated
(block 1638) and displayed in either graphical or numeric form (block
If the consumption rate display is selected (block 1642), then
the rate of consumption is calculated in either English or metric
units (block 1646) and displayed in either graphical or numeric
form (block 1648).
If the consumption rate display is not selected, then it is not
displayed (block 1644).
The calculated volume and flow rates (blocks 1634 and 1648) are
presented on display 292. For example, one indication on display
292 reads: "1.5 liters, 0.25 liter/hr". A typical volume
remaining display (block 1640) reads "23 ounces".
Summary of Modes of Operation
The following is a summary of the above modes of operation and
can serve as an instruction label for the system.
To reset all functions, press reset switch 551 momentarily.
To reset the meter, except time of day, press mode switch 550 once,
then press plus switch 530 once.
To select English or metric units, press mode switch 550 twice,
then press plus switch 530 to select English, or minus switch 540
to select metric.
To enter reservoir volume, press mode switch 550 again, then press
plus switch 530 or minus switch 540 to select the desired value.
To enter the consumption rate goal, press mode switch 550 again,
then press plus switch 530 or minus switch 540 to select the desired
consumption rate goal value.
To enter the volume goal, press mode switch 550 again, then press
plus switch 530 or minus switch 540 to select the desired volume
To select the graph type, press mode switch 550 again, then press
plus switch 530 or minus switch 540 until the desired graph type
To set the time of day, press mode switch 550 again, then press
plus switch 530 to increment the time, or minus switch 540 to decrement
To enable the audible alarm, press mode switch 550 again, then
press plus switch 530 to enable the audible alarm feature, or minus
switch 540 to disable it.
To begin monitoring, press mode switch 550 again, then press plus
To accept the current value of any selected feature, press mode
switch 550 again, or simply wait for the timeout function to return
execution to the start of the program.
Drinking Straw Application--FIG. 7
Various arrangements of the flow meter and display system can be
used. In the embodiment of FIG. 7 the flow meter and electronics
250 and 290 (FIG. 2) are incorporated in a drinking straw 710. Display
292 additionally contains a graph 730 which displays the total volume
of fluid, V, consumed as a function of time, t. Optional filter
740 is shown at the entrance of straw 710. An optional clip 750
attaches the flow meter and straw combination to the side of a glass
or other container, providing mechanical stability. Straw 710 is
typically made of a disposable, semi-rigid plastic, such as polyethylene,
or a composite paper material. Straw 710 is supplied in two pieces
which slide over the ends of tubing pieces 240 and 270 (FIG. 2),
forming a leak-proof coupling. Straw pieces 240 and 270 are later
removed and discarded, and flow meter and electronics 250 and 290
are sterilized for re-use. Alternatively the straw sections can
be made of a "permanent" material, such as plastic and
"permanently" attached to the meter.
In use, all the fluids consumed throughout a given time period
pass through the straw-and-flow meter assembly. Thus the user can
re-fill the same container, or move the straw from a glass to a
bottle, and to any other vessel throughout the time period, providing
a cumulative indication of the volume and rate of consumption of
Drinking Bottle Application--FIGS. 8A and 8B
FIG. 8A shows a side view and FIG. 8B shows a top view of a drinking
bottle 800 with an integral or included flow meter and indicator
display 290. The meter and display assembly is located on the top
lid 810 on bottle 800 near cap 820. Display and control unit 290
is held in contact with assembly 250 and lid 810 by clips 815. Alternatively
the bottle sections can be made of a "permanent" material,
such as plastic and "permanently" attached to the meter.
Optional filter 860 is shown at the bottom of tube 830. Display
292 incorporates a bar-graph 850 to indicate fluid consumption or
other variables as a function of time or other events.
The user opens cap 820 and provides oral suction to withdraw fluid
255 from bottle 800. Tube 830 is optional. If it is not present,
the user must tip bottle 800 to cause liquid 255 to reach the top,
inner surface of lid 800. The user then provides oral suction through
open cap 820 in order to withdraw liquid 255 from bottle 800.
Bottle 800 can be re-filled at any time with any drinkable liquid
255. The volume and rate of consumption of fluid 255 are reported
by the flow meter assembly.
Backpack, Waist-Pack Or Other Fluid Reservoir--FIG. 9
FIG. 9 shows a meter-display assembly in combination with a backpack
or waist-pack fluid reservoir. Flow meter 202 is inserted in tubing
270 attached to backpack or waist-pack fluid reservoir 900. Using
suction 200 the user withdraws liquid from reservoir 900. Meter
and display 202 show the volume and rate of fluid consumption. To
obtain fluid, the user applies oral suction to tubing 270 drawing
the fluid out of reservoir 900. Reservoir 900 can be re-filled at
any time with any drinkable liquid. Again, the volume consumed and
rate of consumption, as well as the alarm functions, are reported
by flow meter 202. A clip, similar to clip 702 (FIG. 7), can be
used to hold meter 202 on the user's lapel or shoulder strap or
other convenient location for easy viewing.
Separable Embodiment--FIGS. 10 and 11
FIGS. 10 and 11 show a separable version in which the electronics
display unit 290 (FIG. 2) is detachable from the impeller section
250. This concept is shown schematically in FIG. 2. Normally the
two sections are held together by clips 815 or similar devices.
The ability to detach the two sections permits sterilization or
replacement of one or both sections. For example, the impeller section
may be a disposable, pre-packaged, sterile unit while the electronics
section is sterilized or replaced between uses, if necessary. Detachment
also permits prior installation of the impeller section within a
In this embodiment, flow progresses from left to right. Fluid enters
connector 816 passes through impeller section 250 and exits through
connector 817. Reverse flow is prevented by optional check valve
Connector 816 is inserted into lower tube 270 (FIGS. 2 and 9),
the lower end of straw 710 (FIG. 7), or tube 830 (FIG. 8). Connector
817 is inserted into one end of tube 220 (FIGS. 2 and 9), the upper
half of straw 710 (FIG. 7), or cap 820 (FIG. 8). Connector 817 can
also be replaced with a smooth pipe section which would contact
the user's lips for direct ingestion of fluid 255 (FIG. 2).
Typical Graphical Displays--FIGS. 12A through 12D
Volume Consumed as a Function of Time--Consumption Rate Goal--FIG.
FIG. 12A shows a graph of desired and actual volume, V, of fluid
over time, T. Dashed line 1205 shows the desired and pre-set rate
of consumption, or consumption rate goal. Region 1210 of the graph
which lies below line 1205 indicates lower-than-desired consumption
of fluids for a period of time. When this occurs, an audible alarm
will sound if that function is enabled. When consumption lies above
line 1205 more fluids are consumed than required, and no alarm
Solid line 1218 represents the total volume goal, i.e. the total
volume which is to be consumed during the present time period.
The graphical formats (well-known program objects) are stored within
the memory (not shown) of microprocessor 300. When a graph type
is selected, microprocessor 300 causes a graph of that type (e.g.,
bar graph, line graph, pie chart) to be displayed on display 292.
As data are available, they are added to the graphical presentation.
Volume Remaining as a Function of Time--FIG. 12B
FIG. 12B shows a graph 1230 of the volume, V, remaining in reservoir
258 (FIG. 2) as a function of time, T. This remaining indication
is useful and is selected when the user desires to know (without
visual inspection of the reservoir) how much fluid is left and how
their consumption rate has progressed.
Volume to be Consumed--FIG. 12C
FIG. 12C shows a bar chart 1240 of volume to be consumed, or total
volume goal. Shaded portion 1245 indicates fluid remaining. Clear
portion 1250 indicates fluid consumed. The same quantity is indicated
at 1218 in FIG. 12A. This is useful when the user desires a graphic,
shaded/unshaded representation of the fluid consumed and remaining.
Volume Remaining--FIG. 12D
FIG. 12D shows a pie chart 1260. The volume of fluid remaining
in the reservoir is indicated by clear area 1265. The volume of
fluid consumed is indicated by shaded area 1270. This chart has
the same utility as the bar chart FIG. 12C, but uses the pie format
which is preferred by some users.
Typical Usage of the Preferred Embodiment
To illustrate the operation and substantial advantages of the present
flow meter, I will describe a typical usage. Assume that a user
plans a day hike and using the backpack-style hydration system of
FIG. 9. The user fills reservoir 900 dons the backpack, and then
prepares the system as follows. All actions on the system of the
preferred embodiment are accomplished by pressing mode switch 550
(FIG. 3), and plus and minus switches 530 and 540 respectively.
First, the hiker resets the system to clear all graphs and counters
by pressing mode switch 550 once, causing "Reset All?"
to appear in display 292 then pressing plus switch 530 once to
accept the reset command. Next, the hiker fills backpack reservoir
900 (FIG. 9) to full capacity. Assume that reservoir 900 holds 2
liters (68 ounces). Then he or she enters the volume of the reservoir
by pressing mode switch 550 until display 292 reads: "Enter
Reservoir Volume, 60 Ounces". The user then presses plus switch
530 eight times until display 292 reads: "Enter Reservoir Volume,
68 Ounces". The user can then press mode switch 550 again to
enter the next mode of operation and cause the current reservoir
volume value to be stored in the memory (not shown) of microprocessor
300. Or the user can simply wait for the timeout function to re-display
the most recent graph and data, at which time the volume of reservoir
900 is automatically stored in the memory of microprocessor 300.
Next, the hiker sets the system to issue an audible reminder, through
loudspeaker 520 to drink fluid or check consumption level at predetermined
intervals. Mode switch 550 is pressed until display 292 reads: "Audible
Alarm ON". The user then presses plus switch 530 thus enabling
of the audible alarm function. Desired consumption rates and levels
are then entered into the memory of microprocessor 300. This is
done by pressing mode switch 550 until "Enter Consumption Rate
Goal, 8 Ounces/Hour" appears on display 292. Plus switch 530
and minus switch 540 are used to increment and decrement the displayed
consumption rate goal. The user then either presses mode switch
550 to save the data and proceed to the next mode of operation,
or simply waits for a timeout which will save the data and return
program control to block 604 FIG. 6A. After the consumption rate
goal has been entered, another pressing of mode switch 550 causes
display 292 to read: "Enter Volume Goal, 64 Ounces". Plus
switch 530 and minus switch 540 are used to increment and decrement
the displayed volume goal. When the desired value is reached, the
user either presses mode switch 550 to move to the next mode of
operation, or waits for the timeout function to return program control
to block 604 FIG. 6A.
At the start of the hike, the hiker activates the hydration system
by pressing mode switch 550 until display 292 reads "Begin
Monitoring". Then the hiker presses plus switch 530 to enable
the monitoring functions. Liquid consumption is monitored by microprocessor
300. If the user hydrates at the proper rate, no alarm will be issued
by speaker 520. If, however, the user lags behind the proper, preset
rate of hydration (see section 1210 in FIG. 12A), speaker 520 will
sound, reminding the user to take a drink.
A further alarm is provided when reservoir 900 reaches a predetermined,
low level, (e.g., 0.5 liter). This alerts the user to refill the
Throughout the day, the user can monitor hydration progress on
display 292. Progress preferably is indicated with line graph 730
(FIG. 7), or alternatively by bar graph 850 (FIG. 8B). Or it can
be simply indicated by numbers, such as shown in FIG. 2. All options
are selectable using mode switch 550 and plus and minus switches
530 and 540 respectively, as described above.
Thus the user will be reminded and hence will be properly hydrated
throughout the day, thereby avoiding dehydration. At the end of
the hike, the user will easily be able to see the level of hydration
that he or she attained. The graph values remain on display 292
until the system is reset in preparation for monitoring another
In addition to use by a hiker, the system can be used by athletes
in various sports, office or factory workers, travelers, people
at leisure, sick persons, or anyone desiring proper hydration.
Summary, Ramifications, and Scope
It is thus seen that the present system combines a method for withdrawing
fluid from a reservoir by orally-applied suction, and measurement
of the volume and rate of withdrawal of the fluid. Any fluid can
be used, including water, electrolyte-replacement liquids, refreshing
liquids, and the like. The rate of consumption of fluid is accurately
reported. If the rate is too low, the system will sound an alarm
to alert the user to drink more for proper hydration. The period
over which the fluid is consumed and the amount of fluid are retained
in the memory of the system and reported on the system's display.
As stated, the present system can be used by all individuals, not
just athletes. The present system is suitable for monitoring and
insuring that anyone has a proper and adequate water or fluid intake.
It can also be used for non-human animals by a pet owner, veterinarian,
zookeeper, or the like to ensure proper hydration of any animal.
Also, the automatic reminder feature can be used to remind a trained
animal to drink if necessary.
Although the above description contains many specificities, these
should not be construed as limiting the scope of the invention,
but merely as providing illustrations of some of the presently preferred
embodiments. Many variations and ramifications are possible.
An "auto-scan" function can be added which automatically
displays each mode of operation for a period of time. This function
can be started and stopped by pressing one or another of the buttons
on the unit.
The monitoring period can be extended from a single event or day
to more events and longer times. With additional programming, different
rates of hydration can be entered for requirements at differing
rates of exertion over predetermined time intervals. Conversely,
the monitoring period can be reduced to encompass hydration over
only part of an event.
Instead of measuring consumption rate in terms of volume consumed
per hour, another time period can be used, such as volume consumed
per 15 minutes or volume consumed per two hours.
In a children's version, the graphical display can incorporate
simple, pictorial representations of fluid consumption.
A 12 or 24-hour hour time display can be used.
The audible alarm can be set to check consumption and alert the
user at predetermined intervals such as 15 30 45 or 60 minutes.
Other computational capabilities can be included in the microprocessor's
algorithms. For example, the user enters her or his weight and the
contemplated duration of exercise. The unit then calculates and
displays the optimal quantity of fluid which should be consumed
during this period.
A communications link can be provided to an external computer,
permitting downloading or uploading of information and data.
The unit is typically waterproof, shockproof, and vibration-resistant.
A key-chain and clip or loop can be attached to the unit.
The unit can be subdivided into two separately operating sections.
The first section is used to measure flow, and the second section
is used to indicate flow and other computationally-derived information.
A communications link can be provided between the two halves. Thus
an embodiment can be made to transmit data from a reservoir to a
An altimeter function can be included to provide added information
for input to the algorithms used to calculate fluid requirements.
While the preferred embodiment is an electromechanical assembly
with a Liquid Crystal Display (LCD) readout, the system can comprise
an entirely mechanical system. This system can comprise a magnetic
link to an impeller assembly and a readout with one or more hands,
similar to a watch, which is geared to move proportionally with
the volume of fluid consumed.
The LCD readout can be back-lit for use in low-light environments.
Alternatively, a light-emitting-diode (LED) readout can be used.
Instead of displaying one graph and a set of numbers at a time,
multiple graphs and multiple rows of numbers can be displayed.
While the drawing figure of the preferred embodiment indicates
a battery power source, other sources can be used. These include
solar photo-voltaic cells, fuel cells, external power supplies,
and the like.
An automatic "sleep", or shut-down, function can be incorporated.
When the unit is not used for an extended period of time, the microprocessor
can enter a low-power, sleep state. It can be re-awakened by signals
resulting from impeller assembly rotation which indicate fluid flow.
An additional graphical indication showing battery reserve can
With the addition of a temperature sensor, the system can adjust
the user's consumption according to the demands of temperature in
a particular environment. A low-battery condition can also cause
an alarm. Alarms caused by low reservoir and drink reminder can
be enabled separately.
The system's display can present data in either English or metric
format. More or fewer buttons can be provided according to the requirements
of a particular design. The system can be mounted on the user's
body, in a straw, in a piece of tubing, in or on a bottle, and so
The system can be separated into its flow sensor and electronic
components. This facilitates sterilization or replacement of all
parts. It also facilitates mounting of the two halves of the system
in their respective locations. The two halves are then held in proximity
by a clamp or clip or other means.
Instead of being separable, the two components can be rigidly attached
within a rugged case.
The components of the system can be made of freeze-resistant materials
to prevent freezing at low temperatures.
Thermal insulation can be incorporated with the fluid reservoir
and delivery tube to provide additional protection against ambient
A purification device can be incorporated into the system to remove
undesirable impurities which may be harmful or bad-tasting to the
The clock can include month, day, year, and day of week displays.
Multiple colors, textures, words, and symbols can be used in the
The display can include a cumulative fluid counter, similar to
an odometer used in vehicles.
A reverse-flow counter can be used to measure the volume of fluid
flowing from the user end of the system into the reservoir. This
enables filling of the reservoir from the user end of the system.
The volume added to the reservoir in this way is automatically added
to the reservoir volume in the microprocessor's memory.
A start-stop function can be employed to permit pausing the data-taking
A stop-watch function can be included.
User preset profile preferences can be employed to customize various
mode settings to a particular user. Once customized, the user would
not have to re-enter a particular value. Also, profiles can be saved
for different users. When a previous user identifies herself or
himself to the system, that person's settings are automatically
entered into each preset value.
In the case of a drinking straw unit, the flow sensor can be integrated
with the upper and lower sections of the straw in one unit.
Different shapes, sizes, and colors of the individual components
can be used to meet various requirements. Other impeller assembly
designs can be used. More or fewer vanes, different angles, and
different numbers of magnets can be used. The vanes can be larger
or smaller, longer or shorter than shown above. Instead of a simple
impeller assembly, a gear- or vane-type rotary metering devices
can be used. Instead of magnetic detection, other rotation-detection
means can be used. Instead of a coil, a Hall-effect device, well
known to those skilled in electronics, can be used.
Instead of incrementing or decrementing with each pressing of the
mode, plus, or minus switches, an automatic increment/decrement
feature can be used. With this feature, simply pressing and holding
a switch causes the current selection to increase or decrease.
With proper calibration, viscous, non-viscous, Newtonian, and thixotropic
fluids can be accommodated, in addition to water and soft drinks.
In the case of a bottle reservoir, the user can manually squeeze
the bottle while applying oral suction. The bottle can have a different
style closure such as a flip-top spout or cap. The bottle can also
have a loop-top to prevent lost lids. The bottle can also have a
hydroporous vent, which permits air to enter the bottle for easy
drinking, but won't allow water to leak when the bottle is tipped.
Additionally, a straw cap can be grommeted to prevent leakage around
the straw. Side measurement markings in English or metric units
or both on the bottle can show the volume of fluid remaining. The
bottle can be made of polycarbonate material, making it virtually
indestructible, or a non-leaching, high-density polyethylene plastic
which will not impart a taste to the fluid.
Accordingly the scope of this invention should be determined, not
by the embodiments illustrated, but by the appended claims and their