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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to medical system for sampling and analyzing
blood or any components of the blood for specific readings as to qualities
of the blood. One specific use of the present invention is for sensing the
accumulation of blood glucose for diabetics. The system is a portable,
pocket-size, battery operated, diagnostic system for detection and
measurement of blood qualities.
2. Description of the Prior Art
Prior art blood glucose devices have operated on the principle of taking
blood from an individual by a variety of methods, such as by needle or
lance. An individual then had to coat a paper strip carrying chemistry
with the blood, and insert the blood-coated strip into a blood glucose
meter or visual comparison against a color standard. There are numerous
blood glucose meters on the market, but are instruments which consume
space and are not pocketable. The instruments usually have to be carried
in a large handbag, or an individual's briefcase, or left at home such as
in the bathroom or the bedroom.
Further, the prior art medical apparatus for sensing blood glucose required
that an individual have separately available a needle or lance for
extracting blood from the individual, strips carrying blood chemistry for
creating a chemical reaction with respect to the blood glucose and
changing color, and a blood glucose meter for reading the change in color
indicating the blood glucose level. The level of blood glucose, when
measured by glucometer, is read from a strip carrying the blood chemistry
through the well-known process of reflectometers for glucose oxidation.
Monitor/reagent strip systems that are now available on the market have
multiple sequential steps that the patient must follow at exact time
intervals. Each step is subject to error by the patient. As in most
monitors, it is the patient's responsibility to periodically calibrate the
monitor against known color standards; validate the efficacy of their
reagent strips and technique by immersing the strips in a control solution
of known glucose content; and, then comparing the color change visually
against the color standard or by using a calibrated monitor.
In the prior art, the procedure for obtaining accurate results from the
time a drop of blood is placed on a reagent strip pad to the time the pad
color change is read in the monitor is as follows. The patient must stick
himself/herself with a lancet. A drop of blood must be squeezed to the
surface of the skin. The drop of blood must then be carefully placed on
the reagent pad, making sure to cover the pad completely and the pad must
never be touched by the finger of the patient to prevent contamination.
Once the sample has been applied to the surface of the reagent pad, the
patient must press a timer on the monitor. At the end of the timing, the
patient must wipe, blot or wash the strip off, using a careful technique.
And for most strips, the patient must place the reacted reagent strip into
the monitor, and press a test button or close a hatch to obtain results.
Prior art commercially available comparable reagent strips or monitors
require operator intervention in a prescribed sequence at exact time
intervals. The prior art is subject to operator error, sequence, timing,
and technique errors. The prior art reagent strips are also subject to
contamination which will affect accuracy of measurement.
The present invention overcomes the disadvantages of the prior art by
providing a hand-held pocketable medical system which includes an
attachable disposable probe package carrying a chemical reagent chemistry
for extracting blood from an individual, delivering the blood to the blood
sensing reagent, or vice versa, in the disposable needle package, and
resulting in a read-out of a level such as blood glucose. The system
includes a microcomputer which is software controlled by an internal
program and, of course, provisions can be provided for external
programming of the microcomputer. The computer controls all timing
functions thereby eliminating human error.
SUMMARY OF THE INVENTION
One general purpose of the present invention is a portable,
shirt-pocket-size, battery-operated diagnostic device/system for use by
health professionals and/or lay patients for the detection and measurement
of certain selected chemical agents or substances for the purpose of
diagnosis and/or treatment of disease. The application is not restricted
to use with human beings. It may also be extended to veterinary medicine
animals. One first application is for insulin dependent and non-insulin
dependent diabetics for the measurement of glucose in serum, plasma,
and/or whole blood.
Another purpose of the present invention is to provide a hand-held
pocketable medical system including an engaging disposable needle or lance
probe carrying the blood sensing reagent for sensing readings of the
blood, such as blood glucose level. The medical system is cost effective
and simple to operate by an individual. The reading, such as an
individual's glucose level, is displayed on an LCD display on the side of
a tubular like pen barrel of the medical system which approximates the
size of an ordinary ink pen which can be carried in an individual's shirt
pocket. The disposable needle probe packages can be carried in a
corresponding hollow tubular pencil carrying a plurality of disposable
probe packages for use as needed. The tubular structure resembling a pen
contains the hand-held pocketable medical system, and the tubular
structure resembling a pencil carries the extra supply of disposable
needles. The pen-and-pencil design provides for the utmost peace of mind
for the individual.
According to one embodiment of the present invention, there is provided a
hand-held pocketable medical system including mechanical or
electromechanical pen like structure for actuating a needle in a
disposable needle or lance probe package, and for enabling a blood sample
inside a finger or on the finger surface to be transferred to blood
sensing reagent chemistry, or the blood sensing chemistry to be
transferred to the blood. The mechanical structure can assume a variety of
spring actuated configurations and can further create a vacuum for drawing
the blood outside of the finger. The disposable needle probe package
frictionally engages onto a socket at the bottome of the tubular hand-held
pocketable medical system such as by snapping, threading, or the like, in
place, and is easily releasable and disposable after a single use. The
hand-held tubular medical system includes photosensing electronics
connected to a microcomputer or custom integrated circuit not only for
analyzing the properties of the blood sensing chemistry in the disposable
probe package, but also for displaying a readout and storing previous
readouts. The electronics includes a verification sequence verifying
operability of the electronics including sensing of a low battery
condition, verifying the condition of an unused disposable needle package,
verifying the presence of a blood sample and subsequently providing
multiple readings to provide for an averaging of results. The result will
not be displayed until the qualification sequence has been successfully
sequenced through verification.
One significant aspect and feature of the present invention is a hand-held
pocketable medical system referred to as a "Med Pen" or a "Med Pen
Mosquito" which is used to extract a blood sample from the body, subject
the sample to chemical analysis, and display the results to the
individual. A disposable needle package, referred to as a "Med-Point"
carries the blood sensing chemistry consisting of a reagent strip, as well
as the needle either for delivering blood to the reagent or for causing
the reagent to be delivered to the blood. Additional disposable needle
packages can be carried in a corresponding structure similar to that of
the medical apparatus referred to as a "Med Pencil."
Another significant aspect and feature of the present invention is a pen
like structure which is mechanical, and actuates upon a predetermined
amount of pressure being exerted on the skin of an individual's finger.
Upon this pressure being sensed, the needle will be actuated down through
an individual's skin for the subsequent result of enabling a blood sample
to be taken from within the finger or blood sample to occur on the surface
of the finger. In an alternative, a button can be pushed actuating the
probe into the skin.
A further significant aspect and feature of the present invention is a
hand-held pocketable medical system referred to as "Med-Pen Mosquito"
which will provide blood glucose readings where the disposable needle
probe package carries glucose-oxidase or like chemical reagent, whereby
once the blood undergoes a colorometric or potentiometric action
proportional to the blood glucose concentration, electronics through the
reflectance colorimeter provide for subsequent processing of the
photosensing of the blood chemistry for displaying of the results on an
LCD display.
A further significant aspect and feature of the present invention is a
hand-held pocketable medical system which can be utilized by an individual
and only requires the engagement of a disposable needle probe package,
subsequent actuation of the apparatus causing a subsequent display on a
visual readout for the desired measurement.
Having thus described embodiments of the present invention, it is a
principal object hereof to provide a pocketable medical system, including
disposable needle packages, which carries blood sensing reagent which
engage thereto providing a subsequent readout on a visual display of a
quality of the blood.
One object of the present invention is to provide a hand-held pocketable
medical diagnostic system denoted as a Med-Pen Mosquito, disposable
medical probe as needle packages referred to as Med-Points or Med-Probes
which engage onto the Med-Pen, and a hollow tubular pencil referred to as
a Med-Pencil for carrying extra disposable needle Med-Point packages. The
disposable needle packages carry blood sensing chemistry or chemistry for
sensing components of the blood for qualities such as glucose level. Other
qualities of any substance can also include urea nitrogen, hemoglobin,
alcohol, protein or other qualities of the blood.
Another object of the present invention is a Med-Pen which is a reuseable
device containing the electronics and software programming, mechanical
apparatus, battery(s), sensor(s), and related circuitry that cause the
functional operation to be performed. The Med-Point or Med-Probe is a
disposable device containing a needle/lance to obtain a blood sample,
typically from a person's finger or toe, and a chemical reagent that
reacts with the presence of blood as a function of the amount of glucose
present in blood. The chemical reagent is sealed inside the Med-Point
probe housing or inside a specific housing for the chemical reagent
obviating the effects of contamination (from fingers), moisture, and
light, thus improving accuracy and precision of measurement by stabilizing
the oxidation reduction or chemical reaction of the reagent prior to use.
The sensor(s) in the Med-Pen/Point system measure/detect via colorometric
and/or potentiometric analysis of the amount of glucose present. This
analog data is converted to a digital readout display quantifying glucose
in miligrams per deciliter (mg/dl) or MMOL/L.
An additional object of the present invention is a self-contained automatic
system. Once the Med-Pen/Point is depressed against the finger (or other
area), no further operator intervention may be required depending upon the
specific embodiment. All operations and performance of the system are
performed automatically and mechanically/electronically in the proper
sequence. Accuracy and precision of the measurement is enhanced because
errors due to operator interpretation, operator technique, timing of
events, and are thereby removed from operator control and influence due to
automatic operation. Pressure of the system against a skin surface of a
predetermined amount based on spring constants or other predetermined
conditions automatically starts the system and sequences the operations
dependent upon the specific embodiment.
Still another object of the present invention is a medical system which is
software based and software intelligent. The system is self-calibrating
through control commands by the software.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Other objects and many of the attendant advantages of the present invention
will be readily appreciated as the same becomes better understood by
reference to the following detailed description when considered in
connection with the accompanying drawings, in which like reference
numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 illustrates a plan view of a hand-held pocketable medical system;
FIG. 2 illustrates an obverse view of FIG. 1;
FIG. 3 illustrates a plan view of the system operation;
FIG. 4 illustrates a cross-sectional view of a first embodiment;
FIG. 5 illustrates an electrical schematic block diagram;
FIG. 6 illustrates a cross-sectional view of a second embodiment;
FIG. 7 illustrates a cross-sectional view of a third embodiment;
FIG. 8 illustrates a cross-sectional view of a fourth embodiment;
FIG. 9 illustrates a cross-sectional view of a fifth embodiment, a
capillary action medical system;
FIG. 10 illustrates a sectional view of a first medical point embodiment;
FIGS. 11-12 illustrate sectional views of a second medical point
embodiment;
FIG. 13 illustrates a sectional view of a third medical point embodiment;
FIGS. 14-15 illustrate a sectional views of a fourth medical point
embodiment;
FIG. 16 illustrates a plan view of a system self-calibrating medical point;
FIG. 17 illustrates a sectional view of a medical probe with self-contained
optical sensors; and,
FIG. 18 is a flow chart of blood transfer to the reagent strip.
FIG. 1 illustrates a plan view of a hand-held pocketable medical system 10
and a disposable medical probe 12 with a needle or lance or the like
carrying blood sensing reagent strip chemistry, all of the present
invention. The hand-held pocketable medical system 10 includes a tubular
cylindrical pen like member 14 and a clip 16 affixed to the top of the
tubular member 14. The disposable medical probe 12 is a narrowing
cylinder, and fits into a socket or similar coupling the cylindrical
member as later described in detail. A visual electronic readout 18, such
as an LCD or the like, including a plurality of digits displays numerical
qualities of the blood, as later described in detail.
FIG. 2 illustrates an obverse plan view of FIG. 1 including an instruction
panel 20 which can be affixed to the cylindrical tubular member 14 of the
system 10.
FIG. 3 illustrates a plan view in perspective of the hand-held pocketable
medical system 10, and a disposable medical probe 12 disengaged prior to
use and after use. Extra disposable medical probes 12 can be stored in a
hollow tubular pencil like cylindrical member 21 which would resemble a
pencil like structure.
FIG. 4 illustrates a cross-sectional view of a first embodiment 30 of the
medical system 10 prior to finger engagement. The embodiment 30 includes a
casing member 32 which is a pen like tubular cylindrical member, and a
core portion 34 disposed therein. A button member 36 includes two
downwardly extending members 38 and 40 although the button action could be
side actuated. An outer spring 42 is disposed between members 38 and 34,
and an inner spring 44 is disposed between members 34 and 40. The outer
spring 42 is held in position by members 68 and 70. The internal actuating
spring 44 is held in position by the lower member 70 and the top of the
button 36. Member 74 further limits travel of the button 36 in an upward
manner and member 75 limits travel downwardly of button 36. Latch 76a and
76b provide for securing of the diaphragm housing core 46. Latches 47a and
47b are disposed at the lower portion of the downwardly extending member
40. A diaphragm housing core 46 positions in notches 48a and 48b in core
part 34. A diaphragm 49 fits over the diaphragm housing core 46. An
optical measurement means includes a light source such as LED 50 and a
light sensor such as phototransistor 52 mounted in an adjacent and opposed
relationship with respect to each other on the walls of the diaphragm
housing core 46. The LED 50 and phototransistor 52 connect to an
electronics unit 54, as later described in detail. The electronics unit 54
is powered by a battery 56 held in position in battery housing 58 by
battery lid 60. A visual display, such as a LCD display 62, positions in a
LCD housing 64 and is held therein by a clear viewing lens 66. The
disposable probe package 12 includes a needle 90, a probe like supporting
structure 92, and a reagent strip 94. The strip 94, while shown in a
horizontal configuration, can be in other configurations such as vertical,
etc. Release tube 96 which provides means for releasing actuator spring
44, positions in the lower portion of casing 32 and engages the inner
surfaces of latches 76a and 76b.
FIG. 5 illustrates an electrical schematic block diagram 100 of the
electrical circuitry for the electromechanical structure of FIG. 4. A
microcomputer 102 or custom integrated circuit controls operation. A
crystal 104 provides the clock signal to the microcomputer 102. A start
switch 106 is actuated upon the pressure of the disposable needle 12
against the skin through pressure. An operational amplifier 108 takes an
analog signal through to an A/D converter 110. A controller 112 controls
power to the op amp 108 and the A/D convertor 110. A piezo electric
chiming transducer 98 is connected to an internal clock of the
microcomputer for chiming at preset times for medical readings. Switches
98a and 98b set the time. A personal computer 114 can connect by a cable
116 to a plug 118 for outputting stored readings. A recall switch 120
recalls each previous reading as the switch is depressed. A voice
synthesizer 122 can also state the reading, the time, and the day. The
microcomputer stores software to verify the electronics, verify the
calibration procedural steps, and controls the measuring of the qualities
as predetermined by the software commands. A power wake up switch or
photoswitch 124 turns on the electronics when a probe 12 is inserted into
the pen 10.
MODE OF OPERATION
The operation of the hand-held portable medical diagnostic system 10 will
now be described in detail, particularly with later reference to sensing
of glucose for an insulin type of diabetic individual. This is by way of
example and for purposes of illustration only and not to be construed as
limiting of the structure or mode of operation of the present invention.
Pushing button 36 loads inner actuator spring 44. The push button 36 locks
in place by latch 47a and 47b and holds spring 44 in the compressed state
as shown in FIG. 4. Diaphragm 49 is thereby compressed by diaphragm
tensioner 51 which is a small projection on the central portion of core
34. By pushing the release tube 96 upward with an individual's finger,
from which blood sample is to be taken, latches 76a and 76b are opened,
and core 34 is forced downwardly by action of the inner actuator spring
44. Downward movement of core 34 drives the diaphragm housing core 46 with
the probe 12 and needle 90 downwardly and simultaneously begins to load
outer spring 42. Needle 90 punctures the finger. Downward motion of core
34 opens latches 47a and 47b so that push button 36 can return to its
neutral position by being forced upward by further expansion of inner
spring 44. Outer spring 42, coaxial to inner spring 44, then can push core
34 upwardly which releases the diaphragm 49, and creates a vacuum in
diaphragm housing core 46. The vacuum draws blood up from ruptured
capillaries in the finger through the needle 90 into the probe 92
whereupon the blood wets the reagent strip 94. Further upward movement of
core part 34 pulls the diaphragm housing core 46 upward so that probe 92
and needle 90 retract from the finger. The diaphragm housing core 46 is
then locked in place by the latch 76a and 76b, all mechanical action ends,
and all elements are in a neutral position. The blood sample on reagent
strip 94 is processed by chemical reaction inside reagent strip 94, and
color change of strip is read from the opposite side of reagent strip 94
by reflection of light from LED 50 to the phototransistor 52. The signal
is processed in electronics of FIG. 5 as later described in detail, and
converted into a numeric value subsequently displayed on LCD 62 which
reflects the glucose level of the blood sample. The disposable probe 12 is
removed from the device by pulling of the probe causing the skirt of
casing member 32 to expand, freeing the probe from the socket.
Further operation of the system is now described. A user attaches a
Med-Point probe 12 to the Med-Pen system 10 which accomplishes two
functions. The first is the Med-Pen and Med-Point are engaged and made
ready for use. The second is the sensor(s) can sense predefined color
bands/areas located inside Med-Point as the pen and point are mated, thus
automatically calibrating through an algorithm in the software. This self
calibration ensures accuracy of measurement before each use; eliminates
the need for operator intervention and operator induced error; verifies
that the chemical reagent inside Med-Point is the correct color, i.e.,
unreacted; and, causes the Med-Pen to provide a visual and/or audible
alarm if the calibration "acceptance criteria" in the software is not
satisfied.
The user places Med-Pen/Point on one's finger or other area from which
blood sample is to be taken. The user pushes down one end of Med-Pen and
holds down until a tactile response indicates Med-Pen/Point may be
removed. The tactile response may be in various forms such as mechanical
click from detent action or even an audible beep.
Med-Pen/Point performs all operations in the proper sequence and does not
require user intervention. A blood sample is transported by vacuum and/or
capillary action to the chemical reagent, and/or chemical reagent is
transported to the blood sample on surface/within finger or other areas.
The vacuum is created by the mechanical action/design of components in the
Med-Pen probe. The capillary action is created by the physical dimensional
design of the Med-Point probe as later described. An internal clock/timer
in the computer is initiated on pressure being exerted in the system. The
chemical reagent reacts with blood/glucose. The electronic sensor(s) can
detect colorimetrically and/or photoimetrically the amount of glucose
present in the blood sample by measuring the change in color of the
chemical reagent and/or the conductivity/impedance of the chemical
reagent, respectively. The chemical reaction between the reagent and the
blood/glucose is time dependent. Multiple measurements are made at
specified time intervals as dictated by an internal clock, thus achieving
three results. There is improved accuracy due to the resolution of the
measurements over shorter time intervals rather than a single measurement
at (x) seconds as in the prior art. There is improved accuracy because
multiple measurements can be averaged optionally throughout the high/low
readings, etc. for linear or non-linear reactions and/or equations. There
is faster response time for operator use; i.e., one doesn't have to wait
30-60 seconds for a reading. The system takes early readings and
extrapolates. The Med-Pen system electronics converts the analog data to
digital format, and displays a quantitative digital readout of glucose in
whole blood expressed in mg/dl or MMOL/L.
The accuracy and precision of measurements is further enhanced because the
chemical reaction of the chemical reagent is stabilized. The Med-Point
housing or self-contained housing for the reagent chemistry can provide a
barrier that insulates the chemical reagent from those parameters that
accelerate the reaction; i.e., light, moisture, contaminants from
fingertips such as salt, fluoride, etc.
The electronics operates on the reflectance colorometer principal where the
blood on the reagent strip undergoes a colorometric or potentiometric
reaction proportional to the blood glucose concentration. The electronics
provides verification of the system, the chemistry of a reagent of an
unused strip, the presence of a blood sample, and provides multiple
readings to average the results. Several readings can be taken at specific
intervals shortly after the blood reacts with the reagent strip. Once two
measurements are made at two distinct time periods, the slope of the
reaction of the chemistry can be calculated towards determining an actual
final glucose value. In the alternative, the software of the microcomputer
can control predetermined samplings at predetermined time intervals and
average the result to determine the final glucose reading after a
predetermined time period, such as 60 seconds. This improves the accuracy
of the final reading. The readings can also be stored and either recalled
by a switch on the side of the pen, or recalled by connecting the pen
through an interconnecting cable to a personal computer for outputting the
readings for specific times on specific days to a video display or stored
for subsequent display or printout.
DESCRIPTION OF ALTERNATIVE EMBODIMENTS
FIG. 6 illustrates a cross-sectional view of a second embodiment of a
medical pen 130. The medical pen 130 includes a housing 131, a button
structure 132 including a spring seat 134, a central core 136 including a
detent 137, a spring seat 138 and a rolling diaphragm 140 connected
between points 142 and 144 of the core 136. Vertically linerally aligned
upper actuator spring 146 and lower spring 148 are between spring seats
134 and 138, respectively, and 138 and 150. Upper latch 152 and lower
latch 154 engage at point 156. A latch 158 is part of housing 131. A push
button extension 160 extends downwardly from the push button 132. The
electronics include a battery 164, a battery cover 166, and the
microcomputer assembly 168. An LCD display 170 mounts to the internal
portion of a battery cover 166 and includes a clear lens 171. A combined
optical sensor 172 provides for illumination, as well as detection, of the
color of the chemical change. A release tube 174 includes catches 176 and
178. A probe structure 180 includes a needle 182 and a reagent strip 184
and a probe housing 186.
MODE OF OPERATION
Pushing the button 132 downwardly loads spring 146 and locks button 132 in
place by action of latch 158 in detent 137. Air inside button 132 is
pushed out through core 136, the porous reagent strip 184, probe 186, and
the needle 182. The finger from which blood sample is to be taken pushes
the release tube 174 upwards, latch 158 is opened so that loaded actuator
spring 146 can drive the core 136 down which loads spring 148 and drives
needle 182 of probe 186 into finger. Needle 182 ruptures capillaries in
finger. When the core 136 has moved all the way down, latch 154 clips into
a detent 151 and releases the latch 152 from engagement at point 156. This
releases button 132 which is forced back to the neutral position by spring
146. Upward movement of the button 132 creates a vacuum inside button 132
and the core 136 by action of rolling diaphragm 140, that vacuum then
reaches probe 186 and needle 182 through porous reagent strip 184, thus
sucking blood from capillaries in the finger into the needle 182 through
the probe 186 so as to wet the reagent strip 184. Extension 160 of button
132 retracts latch 154 from detent 151 after a mechanical delay and finite
time delay defined by distance between latch 158 and extension 160, thus
releasing core 136 which is forced upwards by spring 148 which is then
locked in place by latch 158. This action retracts probe 186 with needle
182 from finger.
The blood sample on the reagent strip 184 reacts with the reagents in the
reagent strip 184 and the resulting color change is read from the opposite
side by optical sensor 172, whose signals are converted by electronics
into a numerical readout on display which reflects the glucose level of
the blood sample. Disposable probe unit 180 is then removed from device.
DESCRIPTION OF ALTERNATIVE EMBODIMENT
FIG. 7 illustrates a cross-sectional view of a third embodiment 200. The
medical pen 200, an alternative embodiment, includes a casing 202, a
spring tensioner 204, a spring 206, a diaphragm tensioner 208, a diaphragm
plunger 210, a diaphragm 212, all positioned about a diaphragm housing
core 214. This embodiment operates with a single spring 206, which secures
between the spring tensioner 204 and the diaphragm tensioner 208. A slide
button 216 secures to the diaphragm tensioner 208. The spring tensioner
204 includes an extension 218 extending downwardly therefrom. The
diaphragm tensioner 208 includes upper latches 220a and 220b and lower
latches 222a and 222b. A release tube 224 secures at points 226a and 226b
to the latches 222a and 222b and at junctions 228a and 228b. The probe 234
includes a needle 236 and a reagent strip 238. The electronics include an
optical sensor 240, electronic circuitry 242, a battery 244 with a battery
cover 246, and an LCD display 248 with a clear lens 250.
MODE OF OPERATION
The probe 234, needle 236, release tube 224, and reagent strip 238 are a
single disposable unit which is inserted into the socket in the pen 200.
Upward thrust of extension 218 at release tube 224 during insertion pushes
spring tensioner 204 upward which loads spring 206. The disposable unit
234 locks into place by action of latch 222a and 222b. Upward thrust of a
finger from which blood sample is to be taken opens junction 228a and 228b
between release tube 224 and probe 234 because probe 234 stops at the
fixed diaphragm housing core 214. Sudden release of the release tube 224
drives the needle 236 into the finger where it ruptures capillaries. At
its upper stop, release tube 224 opens latch 220a and 222b on diaphragm
tensioner 208 which is forced upward pulling the diaphragm plunger 210 and
the diaphragm 212 upward, thus creating a vacuum inside fixed diaphragm
housing core 214. The vacuum reaches needle 236 through diaphragm housing
core 214 and draws blood from the finger through the needle 236 which wets
the reagent strip 238.
The pen 200 has to be manually removed from the finger and reset by means
of the slide button 216. The color change of reagent strip 238 is read
from the opposite side by the optical sensor 240, and the electronics unit
242 converts the color change into a numerical readout on the display 248.
DESCRIPTION OF ALTERNATIVE EMBODIMENT
FIG. 8 illustrates a cross-sectional view of a fourth embodiment of a pen
250. The pen 250 includes a casing 252, a diaphragm plunger 254, a
diaphragm tensioner 256, and a diaphragm 258. The diaphragm housing core
260 supports the diaphragm 258. Upper latch 262 and lower latches 264a and
264b secure to the diaphragm tensioner 256. A slide button 266 also mounts
on the diaphragm tensioner. Internal to the casing 252 are the electronics
268, a battery 270, a screw-on battery cover 272, a display 274, such as
an LCD display, and a clear plastic lens 276 inside the casing. Optical
sensors 278 connect to the electronics 268. A disposable probe 280
including a needle 282 and a release tube 284 having latch detents 286a
and 286b secured to latches 264a and 264b at junctions 288a and 288b. A
reagent strip 290 mounts in the probe housing 292.
MODE OF OPERATION
FIG. 8 illustrates the diaphragm tensioner 256 being pushed downward, thus
depressing diaphragm 258. Diaphragm tensioner 256 locks into place by the
latches 262a and 262b. Probe 280 with the needle 282 and release tube 284
are then inserted and held in place by latches 264a and 264b. Upward
thrust of the finger breaks the junction 288 between the probe 280 and the
release tube 284 which exposes the needle 282. The needle 282 punctures
the finger rupturing the capillaries. At its upper stop, the release tube
284 opens the latches 262a and 262b on the diaphragm tensioner 256 so that
by action of the elastic diaphragm 258, the diaphragm tensioner 256 is
pushed back. This creates a vacuum in the diaphragm housing core 260 which
sucks blood from finger through needle 282 into the probe 280 where the
blood wets reagent strip 290. The pen 250 is then manually removed and
reset by means of the slide button 266 before the next use. The blood is
chemically processed on the reagent strip 290 whose color change is
optically read from the opposite side and converted in the electronics
unit 268 into a visual readout on display 274. Probe 280 with release tube
284 and needle 282 are held by frictional engagement until removed and
disposed of.
DESCRIPTION OF ALTERNATIVE EMBODIMENT
FIG. 9 illustrates a cross-sectional view of a fifth embodiment, a
capillary action medical system 300. The capillary action medical system
300 includes a case 302 with a top 304, a knob 306 with a shaft 308, and a
plunger 310 fits through a hole 312 in the top 304. A button 314 pivots
about a point 316 and includes a latch 318. A lance holder 320 includes a
lance 330 therein. An upper spring 332 fits between the top 304 and the
top of the plunger 310. A lower spring 334 engages between the bottom of
the lance holder 320 and surface 336. A probe 340 includes a capillary
duct 342 and a reagent strip 344 therein. Optical sensor 346,
microprocessor electronics 348 and an LCD display 350 mount on a board
352. A clear lens 354 fits into the case 302. Likewise, a battery 356
applies power to the electronics unit 348 and includes a battery cover
358.
MODE OF OPERATION
Pulling upwardly on knob 306 loads actuator spring 332, and the plunger 310
then locks in place by latch 318. Disposable unit 340 consisting of the
lance 330, probe 340 and reagent strip 344 insert into the system 300. The
top end of lance 330 is held by lance holders 320. Pushing the button 314
releases the latch 318. The plunger 310 is forced down, hitting lance
holder 320. The lance 330 punctures the finger and ruptures capillary
blood vessels. By action of the spring 334, the lance holder 320 returns
immediately to its neutral position, retracting the lance 330. Blood
starts accumulating in the wound channel, and forms a drop on the skin's
surface which is drawn into capillary duct 342 by capillary action. Blood
rests on the reagent strip 344 and starts the chemical reaction. Color
change is then read from the opposite side by the optical sensors 346
connected to the electronics unit 348. The electronics unit converts
signals to a digital readout on display 350.
ALTERNATIVE EMBODIMENTS OF MED POINT
FIG. 10 illustrates a sectional view of a first embodiment of a medical
point 400. A release tube 402 triggers a mechanism in the system 10 which
drives a needle 404 into the finger thereby rupturing capillary blood
vessels. The blood which accumulates in the wound channel is drawn through
the needle 404 into a probe 406 by a vacuum generated in the system, and
subsequently onto a reagent strip 408 which can be porous.
FIGS. 11-12 illustrate a sectional view of embodiments of a medical point
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