U.S. patent number 3,762,879 [Application Number 05/155,153] was granted by the patent office on 1973-10-02 for loop conveyor for automatic chemical testing apparatus.
This patent grant is currently assigned to Hycel, Inc.. Invention is credited to John J. Moran.
United States Patent |
3,762,879 |
Moran |
October 2, 1973 |
LOOP CONVEYOR FOR AUTOMATIC CHEMICAL TESTING APPARATUS
Abstract
A loop conveyor for automatic chemical testing apparatus having
a plurality of rigid slats for carrying a row of reaction tubes
intermediate their ends with the open ends extending upwardly above
the conveyor and the lower closed ends extending beneath the upper
portion of the loop whereby chemical tests may be performed in the
tube as the conveyor is indexed along the various positions.
Heating means positioned inside the conveyor and movable upward for
heating the bottom of some of the tubes and movable downwardly for
allowing the conveyor to rotate. Power means for rotating the
conveyor and lowering and raising the heating means and moving
drying means into and out of the tubes and having a lost motion
connection between the power means and the conveyor for allowing
the heating means to be lowered and the drying means to be
retracted away from the tubes before the conveyor is rotated. A
second lost motion connection for allowing the conveyor to be
rotated before the heating means is raised and the drying means is
moved into the tubes. An indexing pawl engaging the conveyor for
allowing the conveyor to index only a predetermined distance, and a
locking means for holding the conveyor in a fixed position after
each indexing movement.
Inventors: |
Moran; John J. (Houston,
TX) |
Assignee: |
Hycel, Inc. (Houston,
TX)
|
Family
ID: |
26852049 |
Appl.
No.: |
05/155,153 |
Filed: |
June 21, 1971 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
737065 |
Jun 14, 1968 |
3622279 |
|
|
|
Current U.S.
Class: |
422/65;
422/67 |
Current CPC
Class: |
G01N
35/021 (20130101) |
Current International
Class: |
G01N
35/02 (20060101); G01n 001/14 (); G01n
001/18 () |
Field of
Search: |
;23/253,259,292
;134/15,32 ;119/36 ;165/120 ;198/116 ;141/130 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Wolk; Morris O.
Assistant Examiner: Serwin; R. E.
Parent Case Text
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is a divisional application of co-pending
application Ser. No. 737,065, filed June 14, 1968, entitled
Automatic Chemical Testing Apparatus, now U.S. Pat. No. 3,622,279.
Claims
What is claimed is:
1. In an automatic chemical testing apparatus in which a plurality
of reaction containers are indexed through various positions while
test samples are dispersed into the containers and chemical tests
are performed therein, the improvement in a conveyor for carrying
the reaction containers comprising,
said conveyor being an endless loop including a plurality of
substantially rigid sections connected together,
each section including at least one opening for receiving an
elongate reaction container,
an elongate reaction container positioned in each of the openings
having a top opening above the top of the conveyor and having a
lower closed end extending beneath the opening whereby chemical
tests may be performed as the loop is rotated and where the
containers will be inverted, the contents emptied and the
containers recycled,
a temperature controlled liquid heating bath positioned inside said
loop and movable upwardly for heating the bottom of at least some
of said containers positioned on the upper portion of the loop and
movable downwardly for allowing the conveyor to rotate, and
power means connected to the loop for lowering and raising said
heating bath for rotating said conveyor a predetermined amount.
2. The apparatus of claim 1 wherein the liquid heating bath
includes water.
3. The apparatus of claim 2 wherein the conveyor including a
plurality of sprocket wheels and further including means engaging
one of the wheels for allowing the conveyor to index only a
predetermined distance comprising,
a shaft rotated by the power means,
a supporting arm connected to and movable by said shaft,
an indexing pawl rotatably carried by the arm, and positioned to
engage the sprockets on one of said wheels when the shaft is
rotated, and
stop means for limiting the amount of travel of said pawl and thus
the limit of travel of said conveyor when the pawl is in engagement
with the sprocket.
4. The apparatus of claim 3 including sprocket locking means
connected to and rotatable with said shaft, said locking means
being moved into engagement with a sprocket when the shaft is
rotated in one direction, and being moved out of engagement with
the sprockets when the shaft is rotated in a second direction.
5. The apparatus of claim 2 including,
a threaded pin for each opening positioned in the slats and
extending to the openings for holding and aligning a tube in place
in the slat opening, and
a resilient protector positioned between each pin and a tube.
6. The apparatus of claim 2 wherein the power means include,
a power means for rotating said conveyor and for lowering and
raising the heating means,
a lost motion connection between the power means and the conveyor
for allowing the heating means to be lowered and retracted away
from the tubes before the conveyor is rotated, and
a lost motion connection between the power means and the heating
means for allowing the conveyor to be rotated before the heating
means is raised toward the tubes.
7. The apparatus of claim 1 wherein the power means periodically
indexes the loop.
8. In a chemical testing apparatus in which a plurality of reaction
tubes are indexed through various positions where test samples are
dispensed into the reaction tubes and chemical tests are performed
therein, the improvement in a loop conveyor means for carrying the
reaction tubes comprising,
a loop conveyor having a plurality of sprocket wheels supported on
axles and including a plurality of rows of reaction tubes having an
open end and secured to and supported intermediate their ends from
the conveyor with the open ends extending upwardly above the top of
the upper portions of the loop and the lower ends extending beneath
the upper portion of the loop,
heating means positioned inside said loop and movable toward the
bottom of at least some of said tubes positioned on the upper
portion of the loop and movable away from said tubes for allowing
the conveyor to rotate,
piston and power cylinder means for providing the power for
rotating said conveyor and moving the heating means,
a conveyor moving power lever connected to a sprocket wheel through
a one-way clutch and connected to said power means,
an actuating lever connected to said power means and said heating
means for moving said heating means toward and away from the bottom
of the reaction tubes,
a lost motion connection between the power means and the conveyor
for allowing the heating means to be moved away from the tubes
before the conveyor is rotated, and
a lost motion connection between the power means and the actuating
lever for allowing the conveyor to be rotated before the heating
means is moved toward the tubes.
9. The invention of claim 8 including an indexing means for
allowing the conveyor to rotate only a predetermined amount
including,
shaft means adjacent one of the sprockets and actuated by the power
means,
a supporting arm connected to and movable by said shaft means,
an indexing pawl rotatably carried by the arm, and positioned to
engage the sprockets on one of said wheels when the shaft means is
rotated, and
stop means for limiting the amount of travel of said pawl and thus
limiting the travel of said conveyor when the pawl is in engagement
with the sprockets.
10. The apparatus of claim 9 including sprocket locking means
connected to and rotatable with said shaft means, said locking
means being moved into engagement with a sprocket when the shaft
means is rotated in one direction, and being moved out of
engagement with the sprockets when the shaft is rotated in a second
direction.
11. In a chemical testing apparatus in which a plurality of
reaction tubes are indexed to various positions, test samples are
dispensed into the reaction tubes at one position, and chemical
tests are performed at other positions, the improvement in a loop
conveyor means for supporting and indexing the reaction tubes
comprising,
axle supported sprocket wheels, two chains, each chain engaging two
of the wheels, a plurality of transversely positioned rigid slats,
one end of which engages one of the chains, each slat including a
plurality of openings, a reaction tube supported in each opening,
said reaction tubes having open ends extending upwardly above the
top the the upper portion of the loop and having lower closed ends
extending beneath the upper portion of the loop whereby chemical
tests may be performed in the tubes as they are moved along to
various positions as the loop is rotated and where the tubes will
be inverted and the contents thereafter emptied out,
heating means positioned inside said loop and movable upwardly for
heating the bottom of at least some of said tubes positioned on the
upper portion of said loop and movable downwardly for allowing the
conveyor to rotate,
spraying means positioned outside said conveyor for spraying and
cleaning the tubes which are disposed upside down in the lower
portion of the loop,
tube drying means positioned outside the conveyor for drying the
tubes,
piston and cylinder power means for providing the power for
rotating said conveyor and for lowering and raising the heating
means,
shaft means,
heating means support means supporting said heating means and
connected to said shaft means, said support means being lowered
when the shaft is rotated in a first direction and said support
means being raised when the shaft is rotated in a second
direction,
a conveyor moving power lever connected to a sprocket wheel axle
through a one-way clutch and connected to said power means,
an actuating lever connected to said power means for actuating said
shaft means,
a lost motion connection between the power means and the conveyor
for allowing the heating means to be lowered and retracted away
from the tubes before the conveyor is rotated,
a lost motion connection between the power means and the actuating
lever for allowing the conveyor to be rotated before the heating
means is raised,
a supporting arm connected to and movable by said shaft means,
an indexing pawl rotatably carried by the supporting arm, and
positioned to engage the sprockets on one of said wheels and the
shaft means is rotated,
stop means for limiting the amount of travel of said pawl and thus
limit the travel of said conveyor when the pawl is in engagement
with the sprockets, and
locking means connected to and rotatable with said shaft means,
said locking means being moved into engagement with the sprockets
when the shaft means is rotated in said second direction, and being
moved out of engagement with the sprockets when the shaft means is
rotated in said one direction.
12. The apparatus of claim 11 including,
a threaded pin for each opening positioned in the slots and
extending to the opening for holding a tube in place in the slot
opening, and
a resilient protector positioned between each pin and tube.
13. The apparatus of claim 11 wherein the heating means includes a
temperature controlled water bath.
14. In a chemical testing apparatus in which a plurality of
reaction tubes are indexed through various positions where test
samples are dispensed into the reaction tubes and chemical tests
are performed therein, the improvement in a loop conveyor for
supporting and indexing the reaction tubes comprising,
a loop conveyor including a plurality of rows of reaction tubes
having an open end and secured to and supported intermediate their
ends from the conveyor with the open ends extending upwardly above
the top of the upper portion of the loop and the lower ends
extending beneath the upper portion of the loop,
heating means positioned inside said loop and movable upwardly for
heating the bottom of at least some of said tubes positioned on the
upper portion of the loop and movable downwardly for allowing the
conveyor to rotate,
piston and cylinder power means for rotating said conveyor and
lowering and raising the heating means,
a lost motion connection between the power means and the conveyor
for allowing the heating means to be lowered and retracted away
from the tubes before the conveyor is rotated, and
a lost motion connection between the power means and the heating
means for allowing the conveyor to be rotated before the heating
means is raised toward the tubes.
15. The invention of claim 14 including,
cleaning means positioned outside said conveyor for cleaning tubes
disposed in the lower portion of the loop, and
tube drying means positioned outside the conveyor for drying the
tubes.
16. In an automatic chemical testing apparatus in which a plurality
of reaction tubes are indexed through various positions where test
samples are dispersed into the tubes and chemical tests are
performed therein, the improvement in a loop conveyor for carrying
the reaction tubes comprising,
two chains,
a drive wheel engaging at least one of the chains,
a plurality of substantially rigid sections secured to the chains
to form a loop conveyor having upper and lower portions,
each section including at least one opening for receiving a
reaction tube,
a reaction tube positioned in each of the openings having a top
opening above the upper portion of the cnoveyor and having a lower
closed end extending beneath the opening whereby chemical tests may
be performed as the tubes are moved along various positions as the
loop is rotated and where the tubes will be inverted, the contents
emptied, and the tubes recycled,
a temperature controlled water heating bath positioned inside said
loop and movable upwardly for heating the bottom of at least some
of the tubes on the upper portion and movable downwardly for
allowing the conveyor to rotate,
power means for lowering and raising said heating bath and indexing
said loop a predetermined amount, and
means engaging said conveyor for allowing the conveyor to index
only a predetermined distance.
17. The apparatus of claim 16 including,
cleaning means positioned outside said conveyor for cleaning tubes
disposed in the lower portion of the loop, and
tube drying means positioned outside the conveyor for drying the
tubes.
18. In an automatic chemical testing apparatus in which a plurality
of reaction containers are indexed through various positions while
test samples are dispersed into the containers and chemical tests
are performed therein, the improvement in a conveyor for carrying
the reaction containers comprising,
said conveyor being an endless loop including a plurality of
substantially rigid sections connected together,
each section including at least one opening for receiving an
elongate reaction container,
an elongate reaction container positioned in each of the openings
having a top opening above the top of the conveyor and having a
lower closed end extending beneath the opening whereby chemical
tests may be performed as the loop is rotated and where the
containers will be inverted, the contents emptied and the
containers recycled,
a temperature controlled liquid heating bath positioned inside said
loop for heating the bottom of at least some of said containers
positioned on the upper portion of the loop on relative movement of
the bath and the upper portion of the loop towards each other,
and
power means for rotating said conveyor a predetermined amount.
Description
BACKGROUND OF THE INVENTION
The present invention relates to improvements in an automated
chemical testing apparatus which provides automation of routine
chemistry procedures to provide more uniform procedures, greater
efficiency, accuracy and at a lower unit cost than can be performed
manually as well as providing discretionary selectively of the
tests to be performed on each sample. The present apparatus can
generally automate most laboratory tests than can be performed in a
single reaction tube by automatically and selectively picking up
the test samples and dispensing the proper amounts in the
programmed reaction tube, applying the necessary reagents at the
appropriate position, heating the desired tubes to the proper
temperatures, optically analyzing the results of the chemical
tests, and washing and drying the tubes in preparation for the next
tests.
SUMMARY
The present invention is directed to various improvements in an
automated chemical testing apparatus in which a conveyor is
provided for carrying and recycling a plurality of rows of reaction
tubes from one position to the other in which a program control
board is provided for selecting all or any combinations of various
tests on each sample, which tests are automatically performed, the
results recorded, and the components are recycled for continuous
operation.
One improvement in the present apparatus is the provision of a loop
conveyor including a plurality of substantially rigid slats
transversely positioned and each slat including openings for
securely supporting a row of reaction tubes intermediate their ends
from the conveyor with the open tube ends extending upwardly above
the top of the portion of the conveyor and the lower closed tube
ends extending beneath the upper portion of the loop whereby
chemical tests may be performed in the inverted and the contents
thereafter emptied as the conveyor is rotated whereby the tubes
will be in an upside-down position for cleaning.
A still further object of the present invention is the provision of
a tube heating means positioned inside the loop and movable
upwardly for heating the bottom of at least some of said tubes
positioned on the upper portion of the loop, and movable downwardly
for allowing the conveyor to rotate, and tube drying means
positioned outside the conveyor and movable into the tubes for
drying the tubes and movable out of the tubes for allowing the
conveyor to rotate, and the provision of the mechanical linkage
which automatically synchronizes the indexing conveyor movement
with the lowering and raising of the tube heating means and
retracting and extending of the tube drying means, and further
includes means engaging the conveyor for allowing the conveyor to
index only a predetermined distance, and locking means engaging the
conveyor for locking the conveyor in position between indexing
movements.
A further object of the present invention is to provide an improved
means for dispensing test samples into the tubes which includes a
rotary sample table supporting the test samples, a pick up and
dispensing conduit connected to a water filled line with a cylinder
and piston assembly connected to the line for aspiration of a
sample from the sample table and for dispensing portions of the
sample into programmed tubes with a threaded screw actuating the
assembly for accurately controlling the amount of sample picked up
or dispensed, and including an air interface piston and cylinder
connected to the line for creating air interfaces in the line for
reducing any dilution effects or contamination effects on the
dispensed samples, and further including cleaning means for
flushing cleaning media through the conduit and line for reducing
the possibility of contamination between test samples.
Still another feature of the present invention is the provision of
metered means for injecting reagents into the reaction tubes which
include a cylinder and piston positioned between two one-way check
valves, which check valves include flat ground glass valves for
providing a positive seal and which are inert to the reagents and
in which the outlet lines from the dispensing means is directed
into the reagents at an angle to the axis of the reaction tubes to
create a desired mixing action between the reagent and the contents
of the tubes, and in which driving means are loosely connected to
the piston in a transverse direction to avoid misalignment of the
piston in the cylinder.
A still further object of the present invention is the provision of
optical readout means wherein a plurality of cuvettes having
elongated passageways may be lowered into and the contents of the
reaction tubes aspirated into the cuvettes and wherein the optical
readout sequentially scans the cuvettes and the results of the
tests are suitably recorded, and in which the aspiration is
provided by a cylinder and piston wherein the cuvettes are drained
after the tests and are additionally cleaned by a sharp burst of
air to provide a low residual surface factor which reduces
carryover to chemical insignificant levels, and a serpentine
passageway is provided in the cuvette to prevent aspiration of the
samples out of the cuvettes.
Another feature is the provision of an optical readout system in
which a lens having phosphate glass is utilized to reduce the
admissibility of heat from the light source from adversely
affecting the results of the readout, and a filter is positioned
between the cuvette and the light measuring device thereby spacing
the filter from the light source and reducing the adverse effect of
heat on the filter.
Yet a still further feature of the present invention is the
provision of a computerized programming control system for
providing a discretionary and selective control of the tests to be
run on each sample which includes a programmed selection control
board having an actuating switch for each tube for selectively
programming the chemical tests to be conducted on each sample and
in which the computer includes a first contact board electrically
connected to the control board and a second contact board movably
indexed relative to the first contact board in synchronization with
the conveyor and electrically connected to and controlling the
sample dispensing means, the reagent injection means and the
readout means as the second board indexes relative to the first
board and the actuating switches of the first board are
electrically connected to the second board, and further including a
reagent selection board having a plurality of position receptacles
corresponding to each possible position for injecting reagents into
the tubes, and electrical connections for selectively connecting
each of the position receptacles to the desired reagent injecting
means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective overall view of a preferred apparatus of
the present invention,
FIG. 2 is a front skeleton elevational view of the apparatus of
FIG. 1,
FIG. 3 is a rear skeleton elevational view of the apparatus of FIG.
1,
FIG. 4 is an elevational view of one example of a plurality of
reaction tubes showing the position of a sample entry station, the
reagent stations, the heating stations, the readout stations, and
indicating possible types of tests that can be performed,
FIG. 5 is a diagramatic elevational view of the conveyor of the
present apparatus carrying the reaction tubes, and also indicating
possible tube wash and dry stations,
FIG. 6 is an electrical schematic showing the power supply to the
various components of the apparatus,
FIG. 6A is a view of the circuit breaker board,
FIG. 7 is a fragmentary elevational view, partly in section,
illustrating the sample pick up and dispensing components of the
present invention,
FIG. 8 is a view taken along the line 8--8 of FIG. 7,
FIG. 9 is a view taken along the line 9--9 of FIG. 7,
FIG. 10 is a view taken along the line 10--10 of FIG. 9,
FIG. 11 is a view taken along the line 11--11 of FIG. 9,
FIG. 12 is a diagramatic perspective view of the operation of the
carriage and car pick-up arm shown in a dispensing position,
FIG. 13 is a view similar to FIG. 12 showing the carriage car and
arm in a sample pick-up position,
FIG. 14 is a schematic and perspective view, partly in cross
section, illustrating the hydraulic sample pick up and dispensing
assembly,
FIG. 15 is a view taken along the line 15--15 of FIG. 14,
FIG. 16 is a schematic view of the operation and control of the
pick up and dispensing assembly of the present apparatus,
FIG. 17 is a fragmentary elevational view of the endless conveyor
assembly supporting and carrying the reaction tubes,
FIG. 18 is a view taken along the line 18--18 of FIG. 17,
FIG. 19 is a view taken along the line 19--19 of FIG. 17,
FIG. 20 is a view taken along line 20--20 of FIG. 19,
FIG. 21 is a perspective view of the actuating linkages actuating
the endless conveyor, the heating baths and the tube drying means
of the present apparatus,
FIG. 22 is an elevational view, partly in cross section, of the
actuating linkages for indexing the conveyor raising and lowering
the heater baths, and extending and retracting the tube drying
means, and showing the linkages in their first and second
positions,
FIG. 23 is a view similar to FIG. 22 showing the actuating linkages
in their fourth and fifth positions,
FIG. 24 is an enlarged fragmentary elevational view, partly in
cross section, illustrating the operation of an indexing pawl
engaging the sprocket wheel of the conveyor and shown in its first
and second positions,
FIG. 25 is a view similar to FIG. 24 illustrating the position of
the indexing pawl in its third, fifth and sixth positions,
FIG. 26 is an enlarged fragmentary perspective view, partly in
cross section, of the indexing pawl of the FIGS. 24 and 25,
FIG. 27 is an enlarged elevational view of a portion of the
conveyor illustrating details of construction,
FIG. 28 is an enlarged fragmentary perspective view illustrating a
method of securing the reaction tubes to the slats of the
conveyor,
FIG. 29 is a fragmentary cross-sectional view of the conveyor of
the present apparatus illustrating the position of the heating
baths relative to the reaction tubes,
FIG. 30 is a view taken along the line 30--30 of FIG. 29,
FIG. 31 is a diagramatic view of the water connections to the water
heating baths,
FIG. 32 is an enlarged elevational view, taken in cross section, of
a portion of the conveyor illustrating the tube and slat wash
assemblies,
FIG. 33 is a perspective view of the electrical tube heating
assembly of the apparatus,
FIG. 34 is a schematic view of the control system of the end wash
assembly,
FIG. 35 is an enlarged fragmentary elevational view, partly in
cross section, illustrating schematically the connections of the
reagent dispensing assembly,
FIG. 36 is an enlarged elevational view, in cross section,
illustrating the lower portion of one of the reagent metering
assemblies,
FIG. 37 is an enlarged elevational view in cross section of the
upper portion of the reagent metering dispensing assembly of FIG.
36,
FIG. 38 is an enlarged fragmentary perspective of the connection of
the supports for the outlet line of the reagent dispensing assembly
at a position above the reagent tubes,
FIG. 39 is an enlarged fragmentary elevational view, in cross
section, showing the position of the outlet line of the reagent
dispensing assembly relative to a reaction tube,
FIG. 40 is an enlarged elevational view of the readout
assembly,
FIG. 41 is a view taken along the line 41--41 of FIG. 40,
FIG. 42 is a view taken along the line 42--42 of FIG. 40,
FIG. 43 is a view taken along the line 43--43 of FIG. 41 shown in
position for aspirating the contents of the tubes into the
cuvettes,
FIG. 44 is an enlarged fragmentary elevation view, in cross
section, of the fill and expel cylinder and piston assembly,
FIG. 45 is a view similar to FIG. 43 illustrating the movement of
the cylinder relative to the piston for draining the cuvettes,
FIG. 46 is a view similar to FIG. 44 showing the relationship of
the cylinder and drain port relative to the piston for draining the
cuvettes,
FIG. 47 is a view taken along the line 47--47 of FIG. 40,
FIG. 48 is a view taken along the line 48--48 of FIG. 47,
FIG. 49 is a view taken along the line 49--49 of FIG. 47,
FIG. 50 is a view taken along the line 50--50 of FIG. 47,
FIG. 51 is a view taken along the line 51--51 of FIG. 47,
FIG. 52 is an exploded perspective view of the covers above the
exciter lamp in the photocell readout block assembly,
FIG. 53 is an electrical and mechanical schematic of the readout
system,
FIG. 54 is a mechanical and electrical schematic of the mechanical
operation of the testing assembly,
FIG. 55 is a mechanical and electrical schematic of the optical
readout system of the present apparatus,
FIG. 56 is an enlarged fragmentary elevational view, partly in
cross section, illustrating the two-way clutch assembly used in the
present apparatus,
FIG. 57 is a view taken along the line 57--57 of FIG. 56,
FIG. 58 is a view taken along the line 58--58 of FIG. 56,
FIG. 59 is a view taken along the line 59--59 of FIG. 58,
FIG. 60 is a fragmentary view of the program control board of the
present apparatus,
FIG. 61 is an enlarged fragmentary view of the program control
board illustrating the actuating switches and indicating
lights,
FIG. 62 is a cross-sectional view taken along the line 62--62 of
FIG. 61,
FIG. 63 is an electrical block diagram of the control system of the
present invention,
FIG. 64 is an enlarged fragmentary elevational view, partly in
cross section, showing the mechanical structure of the computer of
the present apparatus,
FIG. 65 is a cross sectional view of the sweep and fixed boards of
the computer of the present invention showing the mode of indexing
of one relative to the other,
FIG. 66 is an enlarged cross-sectional view taken along the line
66--66 of FIG. 65, and
FIG. 67 is an electrical schematic of the synchronization circuit
of the present apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and particularly to FIGS. 1 through
5, the automatic chemical testing apparatus or discretionary
sequential multiple analysis apparatus of the present invention is
generally indicated by the reference numeral 20 and generally
includes (1) a loop conveyor or endless belt 22 which carries a
plurality of rows of open topped containers or reaction tubes 24 in
which the various separate longitudinal rows 26 indicate different
chemical tests which may be performed while each separate
transverse row 28 is provided to receive a single individual sample
on which the various tests may be performed as the conveyor 22 is
sequentially indexed carrying the reaction tubes 24 along various
stations at which various steps in the chemical testing are
performed, (2) a sample dispensing assembly 30 which may include a
rotary indexing table 32 for holding the samples to be tested and a
pick up and dispensing apparatus 34 for picking up the required
amount of sample from the indexing table 32 and dispensing each
sample in a single transverse row 28 of tubes 24 in the required
amounts and for the tests programmed, (3) a reagent dispensing
assembly 36 which may include a plurality of containers of reagents
38 connected to metered dispensing units 40 which in turn are
connected to outlets positioned above the reaction tubes 24 at the
desired position or station on the conveyor 22 for dispensing
reagents in the proper sequence and at the proper station in the
tests being performed, (4) suitable heating means 42 which are
positioned for heating the reaction tubes 24 at the desired
stations as the tubes 24 are indexed along the conveyor 22 as
required by the chemical tests being performed, (5) a readout or
testing assembly 44 for analyzing the results of the chemical tests
being performed, (6) cleaning means for cleaning the tubes 24 after
the tests in a particular transverse row 28 has been concluded, (7)
tube drying means for drying the tubes in preparation for reuse and
recycling, and (8) suitable control means for selectively
controlling the sequential multiple analysis and synchronization of
the above mentioned components.
By way of example, the apparatus 20 will be described in use in
running a multiple number of tests on blood serum although, of
course, the present apparatus can be used for a variety of
discretionary sequential multiple analysis chemistry that can be
performed in a single reaction tube. For example only, and
referring to FIGS. 4 and 5 a plurality of 10 longitudinal rows 26
of 60 tubes 24 each are supported and sequentially indexed by the
conveyor 22. As will be more fully described hereinafter, a test
sample will be dispensed into one or more of the 10 tubes in a
single transverse row 28 and as the transverse row 28 is indexed,
will become positioned at the various reaction positions or
stations where the desired chemistry for the different tests
performed in the individual longitudinal rows 26 will be performed
such as heating, mixing, and adding of reagents to perform the
desired chemical analysis, such as by example only, as listed in
conjunction with the individual longitudinal rows 26 in FIG. 4,
after which the transverse rows will reach the readout station
which will analyze and record the measured values. After the end of
the readout, as best seen in FIG. 5, the tubes 24 are inverted,
draining the contents and pass through one or more wash stations
and at least one drying station where they are again returned to
the sample entry position or station for recycling.
Referring now to FIGS. 7 through 16, the sample dispensing assembly
30 includes a pick up and dispensing apparatus 34 which performs
the function of moving towards the rotary indexing table 32 and
picking up a sample to be tested and moves over one of the
transverse rows 28 of reaction tubes 24 and injects a measured
amount of sample into each of the tubes 24 therein for which a test
has been programmed. The rotary indexing table 32 is best seen in
FIGS. 7, 8, 9 and 16, and includes a plurality of sample containers
46 which may be inserted into a plurality of openings 48 which are
circularly and evenly spaced on the indexing table 32. A water
cooling jacket 50 may be positioned beneath the indexing table 32,
as best seen in FIGS. 7, 8, and 9, having an inlet 54 and an outlet
56 to provide a temperature controlled environment for the test
samples in the containers 46 in order that they are not adversely
affected by temperature and particularly the heat generated by the
components of the apparatus 20. A rotary table indexing motor 52
drives the table 32 through a gear box 58 at periodic intervals to
incrementally index the sample containers 46 individually to a
pick-up position in response to a control system which will be more
fully described hereinafter.
The pick up and dispensing apparatus 34 includes a pick up and
dispensing conduit such as needle 62 which is carried by a carriage
car 64 which in turn is movable on and is supported by a carriage
arm 66 which in turn is supported for a swinging movement about one
end, as best seen in FIGS. 7, 8, 9, 10, 13 and 16, whereby the pick
up and dispensing conduit or needle 62 may be moved over the sample
container 46 on the indexing table 32 in the pick-up position, as
best seen in the dotted outline in FIG. 7, to pick up a sample to
be tested after which the carriage arm 66 is returned to the full
line position shown in FIG. 7, over a transverse row 28 of tubes 24
for injecting portions of the sample into the individual tubes 24
for which the programmed tests are to be performed.
As best seen in FIGS. 7, 9, 12, 13 and 16, an air piston and
cylinder 68 is connected to an arm 70, which in turn is connected
to the carriage arm 66 for rotating the arm 66 and thus the
carriage car 64 outwardly over the rotary indexing table 32 and,
after a sample has been picked up, again retracting the carriage
arm 66 into a position over a transverse row 28 of reaction tubes
24. The air supply for actuation and retraction of the piston and
cylinder assembly 68 and thus the carriage arm 66 is supplied
through an air valve 70 (FIG. 16).
The longitudinal movement of the carriage car 64 along the carriage
arm 66 is best seen from FIGS. 12, 13 and 16 in which a carriage
meter 72 drives a pulley 74 through a reversing clutch 76 which in
turn extends, retracts and controls the position of the car 64
along the arm 66 through a control cable 78 which passes around
idler pulleys 81, 83, 85, 87 and 89 and is secured to block 91 on
the car 64 whereby the position of the car 64 along the arm 66 may
be controlled by connecting, disconnecting and reversing the clutch
76.
An overall view of the pick up and dispensing apparatus 34 is best
seen in FIG. 14 which includes a waste and wash cup 80 (FIGS. 9,
11, 7, 14 and 16) in which the cup 80 has an outlet 82 for disposal
of excess sample fluid and a wash cup 84 is provided with a
cleaning media or water wash inlet 86 for admission of a cleaning
media such as water which overflows the wash cup 84 into the waste
cup 80 and out the outlet 82. As best seen in FIGS. 7 and 9, the
waste and wash cup 80 is positioned in line with a transverse row
28 of tubes at the inner end of the arm 66. Since a single sample
which is to be picked up from the indexing table 32 is to be
dispensed into the tubes 24 in a single transverse row in
accordance with the tests programmed, after which any excess sample
32 and dispersed and a new sample is to be picked up from the table
32 and dispersed into a different transverse row 28 of tubes, it is
important that there be no undesired contamination or mixing from
one sample to another sample, and additionally it is desirable that
the dispersement of a single sample into the various tubes in a
transverse row be under the same conditions to avoid variations in
the samples dispensed in the various tubes, such as by example
might be caused by dilution. Thus it is preferred, as best seen in
FIG. 10, to provide a line 88 connected to the pick up and
dispensing conduit or needle 62 which forms a portion of the pick
up and dispensing apparatus 34 and is generally a closed water
system such as water 90 followed by an air interface 92, a second
interface 94 comprising a portion of the sample to be tested, a
second air interface 96 followed by an extra sample aliquot and
then the main sample 98 to be dispensed. By way of example only,
assuming that each of the tests to be performed requires a sample
amount of 0.1 cc, the sample 94 may be 0.1 cc and the main sample
98 may have a volume equal to the number of tests to be programmed
times 0.1 cc plus an additional 0.2 cc amount. Thus, while the air
interfaces 92 and 96 serve the function of preventing mixing
between the water 90 and the main sample 98, the additional sample
94 and the extra sample aliquot picked up from the indexing table
32 prior to dispensing the samples into the tubes 24 will wash the
interior of the line 88 with the same type of material to be
dispensed, thereby reducing any tendency of the previously washed
tube 88 to have, for example, a dilution effect on the main sample
98.
In order to provide the desired pick up of the sample to be tested
and dispensed in the tubes 24, the pick up and dispensing apparatus
34, as best seen in FIG. 14, includes a sample pick up and
dispensing cylinder and piston 100, a water wash piston and
cylinder assembly 102, a needle raising and lowering air piston and
cylinder assembly 104, and an air piston and cylinder assembly 106
for creating air interfaces in the line 88.
As shown in FIG. 14 the needle 62 is in the down position, having
been actuated to the down position by piston and cylinder assembly
104. When the needle 62 is lowered, the water wash piston and
cylinder 102 is actuated back and forth by wash motor 108 through a
rotating arm 110 to suck water into the needle 62 and line 88 and
expel it therefrom, thereby cleaning the line 88 and needle 62 as
fresh water flows through the water inlet 86 into the wash cup 84
and out the drain outlet 32. After the needle 62 and line 88 are
washed, the wash motor 108 is stopped, the piston and cylinder
assembly 104 is actuated to raise the needle 62 and the pick up and
dispensing apparatus 34 is then ready to move into sample pick-up
position over the indexing table 32. When the pick-up position is
reached (FIGS. 7 and 13) the piston and cylinder assembly 104 is
actuated to cause the needle to move downwardly, carrying and
moving the piston 107 in cylinder 106 therewith causing an air
interface 92 (FIG. 10) to be sucked in the line 88 and into the
sample container 46 which has been indexed at the pick-up position
by the table 32. Assembly 100 aspirates a sample 94 into line 88 by
the rotation of worm gear 116 by the motor 112 which moves the
cylinder 118 relative to piston 117. Piston and cylinder 104 is
again actuated to raise needle 62. Assembly 100 and assembly 104 is
actuated to lower needle 62 to aspirate another air interface 96
into the line 88. The aspiration and dispensing motor 112 operating
through reversing clutch 114 rotates worm gear 116 and thus the
cylinder 118 of the aspiration and dispensing piston and cylinder
assembly 100 to aspirate the programmed amount of test sample 98
into the needle 62 and the line 88. When the programmed amount of
sample is picked up from a sample container 46, the motor 112
stops, the piston assembly 104 is actuated to raise the needle 62,
the motor 112 is reversed, thereby reversing worm gear 116 to
retract the cylinder 118 to dispense a segment of the sample 98
back into sample cup 46 to insure that the status for dispensing of
the sample into the tubes 24 will all be similar. The carriage arm
66 is moved back over the transverse row 28 of reaction tubes 24
and the control system actuates the carriage car 64 to place the
needle 62 over the first reaction tube 24 which has been programmed
for testing. The reversing clutch 114 is actuated and a measured
amount of sample is dispensed into a reaction tube 24. The
reversing clutch 114 is deactuated, the carriage 64 is then moved
along to the next tube 24 in the transverse row which has been
programmed for a test, the reversing clutch 114 is again actuated
and a measured amount of sample is dispensed in that reaction tube
24. The process of dispensing a measured amount of sample fluid
into each of the reaction tubes 24 in a transverse row is continued
until all of the programmed tests have received a sample. After the
last programmed test receives a sample, the carriage 64 moves to
the waste cup 30 and the extra sample aliquot is dispensed into the
waste cup 80, the needle 62 is lowered and the wash cycle is again
performed.
Referring now to FIG. 16, the sequence of operation and control of
the pick up and dispensing apparatus 34 is best seen. Information
is received in a sample selection control 115 from the control
system, which will be more fully discussed hereinafter, as to which
tests will be performed and therefore into which longitudinal rows
26 of tubes 24 the sample to be tested will be dispensed. Upon
signals from the sample selection control 115, air valve 71 is
actuated to in turn actuate air piston and cylinder 68 to swing the
carriage arm 66 towards the sample table 32 and at the same time a
signal is sent to the carriage control 119 and aspiration timer 121
and the carriage motor 72 is actuated through its clutch 76 and
pulley 74 to move the carriage car 64 towards the sample table 32.
The carriage motor clutch 76 reverses and stops over the pick-up
position on the table 32 and air valve 120 is actuated and in turn
actuates the piston and cylinder assembly 104 to lower the needle
into the sample container 46 on the table 32. After the air
interface 92, sample 94 and air interface 96 has been obtained, the
aspiration and dispensing motor 112 is actuated and picks up the
programmed amount of sample, the dispenser motor 112 is then
reversed, air valve 120 is de-energized allowing cylinder assembly
104 to raise the needle 62. One segment of the sample is dispensed
back into the sample cup and the arm 66 is moved back over the
reaction tubes 24. The aspiration timer 121 starts the dispensing
timer 123 when the carriage 64 stops over a programmed reaction
tube 24. Dispenser clutch 114 is actuated and a measured sample is
dispensed in the proper tube 24. The carriage clutch 76 is actuated
and the carriage 64 moves to the next programmed test tube where
another sample is dispensed. The dispensing process continues until
all of the programmed tests have received a sample. The carriage 64
then moves to the waste and wash cup 80. At this time the wash
control 108 starts and the needle 62 and line 88 are washed and
filled with fresh water in preparation for the next cycle.
Referring now to FIGS. 17-28, the construction, operation and
function of a preferred form of the loop conveyor or endless belt
22 is best seen. Preferably, the conveyor 22 comprises a plurality
of individual rigid slats 122, each of which hold a transverse row
28 of reaction tubes 24, the slats 122 being secured at each end to
a chain 124 by screws 126 (FIG. 27), and the chains are in turn
carried by sprocket wheels 128, 130, 132 and 134 which are carried
on axles 136 and 138 respectively. The rigid slats 122 are
advantageous in that while allowing the conveyor to rotate around
the wheels, they securely hold the tubes in fixed positions.
Referring now to FIG. 28, the method of inserting and accurately
aligning the tubes 24 in the individual slats 122 before the slats
122 are connected to the chains 124 is best seen. The slats 122
have a plurality of openings 140 sized to receive the tubes 24 and
are placed on a holder 142 having a base 144 and the tubes 24 are
inserted in the holes 140. Holes 146 are drilled in the slats 122
extending to the openings 140. A holding pin 148 is threaded into
the holes 146 against a resilient protector 150 which protects the
tubes 24 from being broken as the pin 148 is secured. Thus, the
tubes 24 are all held in the identical vertical positions relative
to the slats 122 and are securely fastened to prevent them from
later slipping relative to the slats 122 and becoming
misaligned.
The conveyor 22 is periodically indexed a predetermined distance,
such as one transverse tube row, to move the tubes 24 from one
position or station to the next so that the appropriate chemical
steps may be performed upon the programmed samples at the proper
station, time and sequence. Therefore, suitable means are provided
for periodically indexing the conveyor 22 a predetermined distance.
However, since some of the other functions to be performed on the
tubes 24 require a close coaction with the tubes, these functions
may require synchronization with the movement of the conveyor 22.
For instance, during the chemical testing process being performed
in the tubes 24 heat may be required, and the preferred embodiment
provides heating means 42 which may include one or more heating
baths or heaters to satisfy the heating requirements of the
chemical analysis. In addition suitable drying means 152 is
provided which may include a plurality of individual electric
heaters 154 connected to drying heater mount 186 for insertion into
the tubes 24 for drying them after they have been washed. Since
these components during their functional operation coact with the
tubes 24 in such a way as to prevent indexing of the conveyor 22,
these components are synchronized with the conveyor movement 22 for
allowing movement of the tubes 24 from station to station.
Thus, referring to FIGS. 17-26, a power air and piston assembly 156
is provided to supply the power for retracting the tube heating
means 42 and the tube drying means 152, indexing the conveyor 22 a
predetermined amount, and again extending the tube heating means 42
and the tube drying means 152 into their functional position.
Referring to FIGS. 20-23, a heating bath supporting structure 158
is provided with generally includes supports 160, 162, 164 and 166
connected together by linkages 168, 170 and 172 and supported on
shafts 174 and 176.
Drying means actuating linkages 178, 180 are connected to linkages
182 and 184 respectively which are in turn connected to the drying
heater mount 186. The linkages 178 and 180 are connected by pin 175
to linkage 177 which extends and retracts the drying heating mount
186. Linkage 177 is connected by pin 179 to and actuated by lost
motion actuating lever 204.
A stop lug 188 is connected to an arm 190 which is connected to the
shaft 176 so that the stop 188 may release sprocket wheel 132 to
allow movement of the conveyor 22 and may again re-engage the
sprocket wheel 132 to hold conveyor 22 locked in position after the
conveyor has been indexed.
A drive pin 192 is connected to the power air and piston assembly
156 for delivering the power from assembly 156. An arm 194 provides
support for the pin 192. A power lever 196 is connected to the axle
136 connecting the sprocket wheels 128 and 130 to provide the
forwarding indexing movement of the conveyor 22 as the lever 196 is
moved counterclockwise. A lost motion arm 198 is provided connected
between the drive rod 192 and the power lever 196 and includes a
notch 200 which when retracted will engage a pin 202 on the lever
196 so that on the power stroke the lever 196 will move
counterclockwise thereby indexing the conveyor 22. However, before
the conveyor 22 may be indexed in the preferred embodiment, the
heating baths and the dryer heater mount 186 must be retracted away
from tubes 24 so as not to interfere with their movement. A lost
motion lever 204 having a lost motion slot 206 therein is connected
to shaft 174 and receives the drive rod 192 in the slot 206. Thus
the lever 204 will not move with the drive rod 192 until the drive
rod 192 engages one end or the other of the lost motion slot 206.
However, the lost motion of slot 206 is less than the lost motion
of arm 198 so that on the retraction stroke assembly 156 the rod
192 engages the back end 207 of slot 206 retracting arm 204 and
rotating shaft 174 and also retracting arm 177. Rotation of shaft
174 is a clockwise direction lowers the heating bath supports
160-166 and thus the heater baths are moved out of engagement with
tubes 24. Retraction of arm 177 moves linkages 178-184 and retracts
the drying heater mount 186 away from tubes 24.
On the power stroke of assembly 156, the rod 192 and lever 198 move
lever 196, thereby indexing the belt 22. However, the drive rod 192
is allowed to move in the lost motion slot 206 so that the heating
baths supports 160-166 and the individual heater drying elements
154 will not be moved into the proximity of the tubes 24 until
after the conveyor has been indexed, after which time the drive rod
192 will engage the front end 209 of the lost motion slot 206 to
move the actuating lever 204 counterclockwise rotating the shaft
174, thereby raising the heater baths supports 160-166 and pushing
linkage 177, thereby extending the individual drying heaters 154
into a row of tubes 24.
While, of course, the power stroke movement of the piston and
cylinder assembly 156 through the rod 192, the arm 198 and acting
through power lever 196 may be utilized for controlling the limit
of travel of the conveyor 22, a more positive engaging pawl 208 may
be rotatably supported on shaft 176 and arranged to engage the
teeth on sprocket wheel 134.
Pawl 208 is rotatable about a pin 210 on arm 212 which is in turn
fixedly secured to shaft 176. In the waiting position (first
position) the pawl 208 is kept out of engagement with the teeth of
sprocket wheel 134 by spring 214 between the pawl 108 and the arm
212 causing the pawl 208 to engage a stop pin 216 positioned on
linkage 212. However, when the power cylinder 156 retracts thereby
lowering the heating baths and retracting the drying heaters, shaft
176 is rotated bringing the end of the pawl 208 into engagement
with the sprocket teeth of wheel 134 (FIG. 24). Further rotation of
the shaft 176 causes the end of the pawl to become fully engaged
with the sprocket teeth (FIG. 25, third position). As the power
cylinder 156 moves on the power stroke and indexes the belt 22, the
sprocket 134 will rotate the pawl to the fifth position as best
seen in FIG. 25 at which time the pawl 208 will engage a stop pin
215 on the arm 212 thereby preventing further rotation of the
sprocket wheel 134 and the conveyor 22.
Referrring now to FIG. 23, stoppage of the rotation of the sprocket
wheels and the conveyor 22 by the pawl lock 208 causes the lost
motion arm 298 to become released from power lever 196 as the notch
200 by virtue of its rounded back edge 201 will move off of the pin
202 and return to the first edge 201 will move off of the pin 202
and return to the first position (FIG. 22).
After the conveyor 22 is stopped and thus indexed in a new
position, further movement of the power stroke of the power
assembly 156 causes the drive rod 192 which is by then moved
through the lost motion slot 206 to engage the end 209 of the slot
206 and move lost motion lever 204 to rotate shaft 174 causing the
heating baths supports 160-166 to move upwardly, moving the heating
baths into engagement with the tubes 24 which are in the newly
indexed position. Movement of lever 204 simultaneously moves arm
177 and linkages 178 and 180 which in turn move linkages 182 and
184 to move the drying heater block towards the new row of tubes 24
in the drying position whereby the individual heaters 154 are
inserted into the tubes to perform the drying function. Rotation of
shaft 176 also rotates arm 190 and stop pin 188 into engagement
with the sprockets on wheel 132 thus holding the conveyor 22 in a
locked position. Also, rotation of shaft 176 in moving linkage 178,
as best seen in FIG. 25, moves the locking pawl 208 out of positive
five and into position six or its original waiting position one
(FIG. 24).
While the form of the heating means 42 for heating the reaction
tubes 24 to the temperatures necessary for performing the chemical
analysis will of course depend upon the chemical tests performed,
one form is shown in FIGS. 29, 30, 31, 33 and 34 for satisfying the
heating requirements of the tests listed as programmed in FIG. 4.
Thus a heater tray 217 is provided for supporting a P.B.I. electric
heater 218 for providing a temperature of about 230.degree. C. at
stations 4-8 in the longitudinal row in which the P.B.I. test is
performed (FIG. 4), a water bath 220 is provided for a temperature
environment of 37.degree. C., and a water bath 222 is provided for
creating a temperature environment of 80.degree. C. The heater tray
217 is supported by the heating bath supporting structure 158 (FIG.
21) which are slidably engaged on shafts 174 and 176 by slidable
guides 224 and 226, and are engaged and are raised and lowered on
supports 160-164 as previously indicated.
Referring now to FIG. 33, the P.B.I. heater 218 may be an electric
heater having a plurality of openings 228 for enclosing the
reaction tubes 24 when the heater 218 is raised and includes
suitable electrical connections 230 for supplying the necessary
electrical power for heating.
Water in baths 220 and 222 is circulated by means of pumps 246 and
248 respectively through suitable heaters 242 and 244 located in
tanks 243 and 245 respectively. By suitable means of heater control
the temperature in the baths 220 and 222 is controlled. Water to
baths 220 and 222 is provided through line 232, branch lines 234
and 236 and controlled by valves 238 and 240 respectively. Excess
water in baths 220 and 222 flows into overflows 250 and 252
respectively and drains into sump 254 which has an outlet 256
through which drain water is disposed.
Referring to FIG. 5, it has been previously indicated that as the
conveyor is indexed, and after the conclusion of the chemical
analysis, the tubes 24 are inverted, thereby draining the contents
therefrom, and are then washed in preparation for recycling.
Referring now to FIG. 32, wash pipes 258, 260 and 262 are provided
having spray nozzles 264, 266 and 268, respectively for directing a
spray of cleaning water at various stations into the tubes 24 and
onto the slats 122 for washing and cleaning the tubes and conveyor.
The contents of the tubes 24 and the spray water are received in a
drain sump 254 for disposal.
Referring now to FIG. 34, a master timer 272 is provided as part of
the control circuit which will be more fully described hereinafter,
which after the tests have been programmed controls the rotary
indexing table 32 as well as controlling air valve 274 which in
turn controls the power air piston assembly 156 which drives the
conveyor 22. After the last programmed test is completed the master
timer 272 is deactuated and at that time actuates the end wash
timer 276 which will continue to index and actuate the power
assembly 156 to index the conveyor 22 for a predetermined number of
cycles to insure that all of the tubes 24 are washed and
cleaned.
Referring now to FIGS. 35-39, the reagent dispensing assembly 36 is
best seen in which the various reagents required for the various
chemical tests are provided in reagent containers 38 and are drawn
therefrom by metered dispensing units 40 and dispensed into the
reaction tubes 24 at the proper positions or stations and in the
proper amounts for performing the desired programmed tests.
Preferably, the metered dispensing units 40 include a glass
cylinder 278, a Teflon piston 280 therein for drawing in a metered
amount of reagent from the connected container 38 through a first
check valve 282 and dispensing the metered amount of reagent
through a second check valve 284 to a tube 24. It is desirable that
the components of the reagent dispensing assembly 36 be of glass,
Teflon or other inert material which will withstand and hold up in
extended use with the chemical reagents used. The check valve 282
is connected through a fluid passageway 286 to one of the reagent
containers 38 and generally includes a compartment 288 having a
polished glass valve seat 290 in communication with the passageway
286 and a glass valve element 292 preferably in the form of a
cylindrical element. A second fluid passageway 294 leads from the
compartment 288 into the interior of the cylinder 278 for drawing
reagent from a container 38 into the cylinder 278 on the suction
stroke of the piston 280. A bypass notch or passageway 296 is
provided at the outlet edge of compartment 288 having a length
longer than the width of element 292 to insure that passageway 294
remains open on the suction stroke of the piston 280 so that the
reagent may be drawn through passage 286, through compartment 288,
and into passageway 294 and the cylinder 278. However, when the
piston 280 is on the dispensing stroke, valve element 292 is forced
into contact with the polished glass seat 290 providing a positive
seal for sealing off any return of the reagent back through
passageway 286 to container 38 and instead forces it out of a
passageway 298 and through the check valve 284 to a reaction tube
24. The structure of check valve 284 is similar to that of check
valve 282. Thus on the suction stroke of the piston 280, a metered
amount of fluid flows through the first check valve 282 while the
second check valve 284 is closed. On the dispensing stroke of the
piston 280 the first check valve 282 is closed and the second check
valve 284 opens allowing fluid to be dispensed through fluid
passageway 298 to a reaction tube 24.
The Teflon piston 280 includes first and second flanges 300 and
302, which maintain a seal with the glass cylinder 278. Collar 303
serves to align piston 280 and the piston rod 304 in the cylinder
278. As best seen in FIG. 37 a T slot 306 is provided in the end of
piston rod 304 for connection to an actuating assembly and is
adapted to engage a T head 308 (FIG. 36). The T slot 306 thus
provides a loose fitting connection with the T head 308 in a
transverse direction so that in the event the T head 308 is not
accurately aligned with the piston rod 304 there will be sufficient
transverse play in the connection so that the piston 280 will
remain axially aligned in the cylinder 278 and not bind in the
cylinder 278 or break the glass cylinder 278 because of
misalignment as the piston is reciprocated therein.
Referring now to FIG. 36, the power source for reciprocating the
piston 280 in the cylinder 278 for dispensing the reagent may be an
air piston and cylinder assembly 310 in which an air inlet 312
directs air to one side of a piston 314 to move stem 316 and thus
the T head 308 connected to the piston rod 304. A spring 318 is
provided acting between a stop 320 and piston 314 for moving the
piston 314 in a suction direction. An orifice outlet 322 is
provided to limit the rate of outlet air on the suction stroke in
order to limit the rate of suction speed for the meter dispensing
unit 40 in order not to have an adverse effect on the reagent or
damage the unit. An electrical operated valve 324 is provided for
actuation of the dispensing unit 40 by admission of air to the
lower side of piston 314. The distance that the stem 316 and thus
the piston 280 (FIG. 37) moves on the dispensing stroke can be
adjusted by a sleeve 328 which is locked in adjusted position by a
nut 330 to limit the amount of fluid drawn into and dispensed from
the cylinder 278. Thus, by suitably adjusting the sleeve 328 the
stroke of the piston 280 and thus the amount of metered reagent may
be accurately controlled.
Referring now to FIG. 35, an outlet line 332 is connected to each
of the reagent metered dispensing units 40 for receiving the
metered amount of reagent and dispensing it into a reaction tube
24. Referring to FIGS. 38 and 39, dispensing line holding bar 334
is supported by adjustable support 336 for positioning of the bar
334 over a transverse line 28 of reaction tubes 24. The bar 334
includes a plurality of openings 338, each of which is directed
into the top of a reaction tube 24 positioned thereunder, for
supporting the outlet end of dispensing line 332. As best seen in
FIG. 39 it is preferred that the openings 338 be at an angle to the
longitudinal axis of the tubes 24 so that the incoming reagent will
be directed into a tube 24 at an angle thereto adjacent the top of
the curved bottom of the tube 24 to create a swirling action as the
reagent is dispensed therein to provide sufficient agitation and
swirling of the mixture to thoroughly mix the reagent with the
sample therein thereby eliminating the requirement of additional
shaking or stirring of the mixture to secure the desired chemical
reaction. Of course, a plurality of the support bars 334 are
provided along the top of the transverse rows of the reaction tubes
24 depending upon the number and stations at which the reagents are
to be dispensed which depends upon the chemical tests being
performed by the apparatus.
As indicated in FIGS. 4 and 5, after the sample has been dispensed
into the tubes 24, the reagents added at the proper stations during
the test and properly heated, the tubes are indexed to a readout
station in which the results of the test are analyzed such as by a
readout assembly 44 such as an optical readout. Referring now to
FIGS. 40-55, the readout assembly 44 is best seen, and in
particular FIGS. 40-42 in which a plurality of cuvettes 340,
preferably optically matched, are provided, one each for each of
the longitudinal rows 26, which are positioned over the reaction
tubes 24 at the readout station and which are transversely aligned
and supported by a movable support or readout block 342 which is in
turn supported by guides 344 at each end which is connected to a
piston rod 346 (FIGS. 40 and 42) which is connected to an air
piston and cylinder assembly 348 for raising and lowering the
readout block 342 for lowering the cuvettes 340 into the tubes 24
whereby the fluid in the tubes 24 may be aspirated into the
cuvettes, optically analyzed and drained again into the tubes 24
after which the piston and cylinder assembly 348 raises the readout
support block 342 out of the tubes 24 so that the conveyor 22 may
be indexed and another set of tubes 24 brought to the readout
station and analyzed.
After the air piston and cylinder assembly 348 lowers the readout
block or support 342 downwardly and the lower end of the cuvettes
340 which preferably includes an elongated passageway 341 are
inserted into the tubes 24 a fill and expel air piston and power
assembly 349 (FIGS. 41, 43, 45 and 54) is actuated and is connected
to a movable bar 350 by piston rod 352 which is supported at each
end by slidable rods 354 and 356. The actuating bar 350 is
connected to a plurality of individual arranged syringe pistons
358, one for each cuvette 340, which is slidable in a cylinder 360
with a line 362 connecting each cylinder 360 to one of the cuvettes
340. Thus on actuation of the fill and expel piston and cylinder
assembly 349 on the suction stroke the actuating bars and all of
the piston rods 352 are retracted drawing back all of the pistons
358 creating a suction in the lines 362 and in each of the cuvettes
340 to suck up the liquid from the tubes 24 into the cuvettes. A
serpentine passageway 343 is provided between the passageway 341
and the body of the cuvettes 340 for slowing the flow of fluid into
chamber and preventing aspirating the fluid into line 362.
Referring now to FIG. 44, it is noted that when the syringe piston
258 is retracted in the syringe cylinder 360 the piston seal is not
moved past an air drain port 364 provided in the cylinder wall.
While all of the pistons 358 are connected to the actuating bar
350, all of the syringe cylinders 360 are connected to a drain bar
366, which is connected to a piston rod 368 which is in turn
connected to a drain piston and cylinder assembly 370. The drain
bar 360 is supported on movable support rods 372 for slidable
movement thereon.
After the optical readout of the liquids in the cuvettes 340 is
completed, the air piston and cylinder assembly is actuated to
raise the readout block 342 from the reaction tubes to its original
position shown in FIGS. 40 and 41. It is then desired to drain the
cuvettes 340 of the liquid therein, and the drain piston and air
assembly 370 is actuated, as best seen in FIG. 45 thereby moving
the drain bar 366 away from the syringe pistons 358 and thus moving
the syringe cylinders 360 in such a manner to move the air port 364
past the piston 358. The air port 364 is moved, as best seen in
FIG. 46, past the piston 358 to the dotted position thereby
allowing air to enter the syringe cylinder 360 relieving the
suction in the lines 362 and allowing the liquid in the cuvettes
340 to drain back into the reaction tubes 24.
In order to further drain the cuvettes 340 the fill and expel air
piston and cylinder piston assembly 349 is actuated to move the
actuating bar 350 and thus the pistons 358 back into the syringe
cylinders 350 providing an air impulse through the lines 362 and
the cuvettes 340 as the piston 358 passes the air port 364 to
assist in further draining the readout tubes 340. In addition, a
further air blast may be provided to further drain the cuvettes as
the drain piston and air assembly 370 is actuated to return the
drain bar 366 to its original position thereby causing the syringe
cylinders 360 to move towards the syringe piston 358 creating an
additional air blast.
As best seen in FIG. 54 a readout timer 374 is provided connected
to air valves 375, 377 and 379, respectively for suitably actuating
and reversing the air piston and cylinder assemblies 348, 349, and
the drain assembly 370 to sequentially lower the cuvettes 340 into
the reaction tubes 24, to aspirate the sample into the cuvettes 340
and after the readout has been accomplished, to raise the readout
cuvettes 340, drain the fluid therefrom, and expel the remainder of
the fluid therein by air blasts so that the readout assembly is in
condition for the next cycle.
As previously mentioned, it is preferable to perform the readout
tests optically and such a system is shown schematically in FIG. 55
wherein a light source such as an exciter lamp 376 is provided to
direct light through a lens 378, through the sample in a cuvette
340, through a filter 380, and to a light measuring means such as
photovoltaic cell 382, wherein the value of light intensity
measured by the photoelectric cell 382 which is a measure of the
property being tested, is transmitted through electrical
calibration control circuit 384 to a readout device such as a
recorder 386. The physical structure of the readout block 342 is
best seen in FIGS. 47-52 wherein the exciter lamp 376 provides a
light source through the lens 378 which is preferably phosphate
glass which performs the function of not only collimating or
directing the rays of light from the lamps 376 into parallel rays
but also absorbs heat to prevent the heat from the lamps from
affecting the optical testing of the sample. Chrome reflectors 388
are also provided behind the exciter lamp 376 to direct the light
through the lenses 378 and through a window 390 through the readout
cuvette 340 which preferably include a window 392 with the
remainder of the cuvette being amber colored to cut out stray
light. After the light passes through the sample in the cuvettes
340 it passes through the filter 380 which filters out undesired
light and allows only the spectrum of light being measured to pass
through to the photocell. It is preferable that the filter 380 be
positioned between the cuvette 340 and the photocell 382 in order
to prevent the heat from the lamp 376 from adversely affecting the
filter 380.
However, as previously mentioned, it is further desirable to
control the heat environment in which the readout tests are
performed and as the exciter lamps 376 radiate a great amount of
heat, the readout block 342, as indicated in FIGS. 47, 48, 49, 50
and 51 include water passageways 393 so that water may be passed
therethrough for cooling the block 342. In addition, in order to
provide additional cooling for the exciter lamps 376, the readout
block 342 may include air partitions 394 and 396 (FIGS. 47 and 52),
each of which includes a plurality of air vents 399 for allowing
the heat to escape from the lamps 376. However, the vents 399 on
the member 394 are out of vertical alignment with the vents 399 on
member 396, thus allowing heat to escape, but reducing the
admissibility of stray light into the lamp compartment.
Referring now to FIG. 53, an electrical schematic of the readout
system which includes portions of the control systems of FIGS. 54
and 55 is best seen. As will be more fully described in detail, a
push button program panel 398 is provided in which the various
tests desired to be performed by the apparatus are programmed, with
the information being transmitted to a computer 400. An actuating
operate button 402 is depressed to actuate and start the master
timer 272 controlling the various functions in synchronism. At the
proper point in the operating cycle the readout timer 374 (FIG. 54)
actuates the readout block air cylinders 348 to place the cuvettes
340 into the reaction tubes 24. The test samples are then aspirated
into the readout tubes 340 by the air piston assembly 349. During
the readout cycle each of the exciter lamps 376 directs a light
beam through a cuvette 340 to a photocell 382 for each longitudinal
row of tubes 24. Each exciter lamp 376 has a lamp failure relay 404
which is connected to an alarm system 406 to provide an audible
sound in the event that one of the exciter lamps 376 fails.
The recorder timer switch 410 is then actuated to begin its
sequential scan through each of the tests programmed by the
apparatus by sequentially connecting the output of each photocell
to the recording pen on the recorder 386, the output signal is
clamped, the chart paper advances registering the signal on the
chart paper in such a manner as to indicate the concentration of
the unknown in the solution undergoing the analysis. During the
process of scanning, lamps 458 are illuminated indicating the test
being registered, counters 459 pulsed sequentially counting each
test being registered, and the re-setting of the programmed relays
461. Just prior to the completion of the scanning cycle, a pulse is
sent to the readout timer 374 to enable it to complete its final
phase of the readout cycle, suitably actuating the controls in FIG.
54 to drain the tested sample from the cuvettes 340 and retract
them from the tubes 24 in preparation for the next cycle.
In addition, a plurality of electrical calibration control circuits
384, each connected to a photocell 382 are provided. As a part of
each electrical control circuit 384, a "blank" potentiometer 385
and "reference" potentiometer 387 may be provided to control and
calibrate the output from each photocell 382 in accordance with a
known sample being tested. Used in conjunction with each other,
these potentiometers 385 and 387 make it possible for the
information transmitted to a readout device such as recorder 386
read directly in the desired measured units in spite of any
individual differences in cuvettes, photocells, filters, etc.
Referring to FIGS. 14 and 15 a clutch 114 is connected to motor 112
to provide a two-way drive for the pick up and dispensing apparatus
34. Referring now to FIGS. 56-59, a more detailed description of
the structure and operation of the clutch 114 may be best seen. The
clutch 114 is for providing a two-way clutch between the drive
shaft 422 and the driven shaft 420. In a conventional clutch the
driven shaft 420 is connected in housing 421 to a cam member 424
having cam surfaces 426 thereon which are adapted to engage clutch
bearings 428 and cause them to engage a driving member housing 430
which is connected to the driving shaft 422. However, this
conventional clutch will only operate in a single rotation
direction of the drive shaft 422 and the direction is determined by
the direction the springs 432 are connected between the driven
housing 421 and the cam member 424. A forward indexing pin 442 is
provided on housing 421.
Added to the conventional clutch is a reversing pawl 434 which is
spring loaded rotatably mounted on pin 440, housing 430 and
yieldably urged against a stop pin 436, and a reverse pin 438.
When the driving shaft 422 is turned in a counterclockwise
direction 423, the driven shaft 420 turns conventionally as the
springs contract and engage the internal bearings 428 in the clutch
until an external stop means such as a solenoid switch 444 having
an actuating lever 446 which, when actuated into position, stops
the driven shaft by engaging forward indexing pin 442 thus
expanding the springs 432 and releasing the internal bearings 428.
The drive shaft 422 continues to turn and the spring loaded pawl
434 springs past the reversing pin 438 and thus the driven shaft
420 is disconnected and will only turn when the forward indexing
pin 442 is released by the solenoid switch 444 and lever 446.
Whenever the drive shaft 422 is driven in a clockwise direction
425, the driven shaft 420 begins to turn clockwise as soon as the
pawl 434 engages reverse pin 438. Thus, the two-way clutch 114 may
be simply actuated in either direction of rotation of the drive
shaft.
Referring now to FIGS. 6 and 6A, the electrical power supply
circuit and circuit breaker switch board are best seen. The circuit
breaker board 445, also seen in FIG. 1, has various individual
circuit breakers labeled as indicated with the corresponding
numeral in the enclosed circle shown in position in FIG. 6. The
circular enclosed figures are push button circuit breakers which
pop out when an overload occurs, thereby causing an audible alarm
whereby the operator may quickly check the control board to locate
faults. Thus, a power input is provided at 447 and to a
conventional magnetic contactor 448. Circuit 1 is the power supply
to the various control circuits with branch circuit 2 being a 115
volt ac circuit, circuit 3 being a 48 volt dc supply circuit,
circuit 4 being the power supply to the air compressor 450 (FIGS. 2
and 3) which provides the air supply for various machine functions,
circuit 5 is to the various bath heaters 218, 242 and 244, circuit
6 is to the drying heaters 154, circuit 7 is to the computer 400,
circuit 8 is to the endless belt or conveyor 22, circuit 9 is to
the sample dispensing assembly 30, circuit 10 is to the tube wash
and wash valves, circuit 11 is to the drain timer and drain motor
(now shown), circuit 12 is to the reagent dispensing solenoids 324,
circuit 13 is to the readout 44 and photocells 382, circuit 14 is
to the recorder 386, and circuit 15 is to the 12 volt dc power
supply for lamp failure relays 404 and the exciter lamps 376.
The push button panel 398 (FIG. 1) is best seen in FIGS. 60-62, and
includes a plurality of vertical rows 452 of indicating lights and
buttons, each row corresponding to each transverse row 28 of tubes
24, and assuming that there are 10 longitudinal rows 26 of 60
tubes, each vertical row 452 of push buttons will include 10
buttons, one for each row which when pushed indicates that the test
in that longitudinal row is programmed for a particular sample. In
addition to the 10 individual selected discretionary program
buttons each row includes a button 454 labeled P indicating that a
profile or the entire 10 tests are to be run on that sample, and
also includes a release button 456 for disengaging all of the
buttons pushed in that particular row 452 in the event of error or
in the event that it is desired to change the tests being
programmed. In addition, station numbering lights 460 and
indicating lights 458 for indicating the status of the tests on
that particular vertical row 452 are provided. The push buttons on
the panel 398 are connected to a fixed section or stationary board
462 of the computer 400. The panel 398, in the example shown, has
60 buttons in horizontal rows whereby sixty samples may be
programmed for the various tests programmed into the apparatus.
The computer 400 is best seen in FIGS. 64-66 and includes a sweep
section 464 connected to a worm gear drive 466 which is in turn
connected to a sweep board clutch 468 driven by motor 470 for
controlling the relative position of the movable section 464 to a
fixed section 462. The sweep board motor 470 actuates and indexes
the sweep board 464 in synchronism relative with the indexing of
the belt 22 so that the information programmed on the programmer
398 is suitably transmitted to the proper function controls whereby
the sweep board then transmits the information such as which tests
are to be performed, which readout is to be actuated which also
depends upon which test is to be performed, how much sample
material the pick up and dispensing apparatus 34 is to pick up
which also depends upon the number of tests to be performed on each
sample, and dispenses the proper reagents which also depends upon
which tests have been programmed. For example, the stationary board
462 corresponds to and is electrically connected to the panel 398.
That is, board 462 will include 10 rows of 60 terminals or pin 463
connected to corresponding buttons on panel 398. However, the sweep
board 464 will require terminals 465 corresponding to the number of
tube reaction stations on the conveyor, in the example given 20, at
which discretionary functions may be programmed and performed. Thus
as the sweep board 464 indexes past the stationary board 462 its
pins 465, which are preferably spring loaded as shown in FIG. 66,
move against pins 463 and pick up the programmed information and
transmit it to the various systems which perform the various steps
in the chemical tests at the twenty work stations (FIG. 4). Since
the sample being tested travels through 20 possible work stations
on the belt 22 from sample delivery to sample readout, the sweep
board 464 signals the various systems that a function is to be
performed in a particular cycle. As previously indicated the
information sent from the sweep board includes: whether further
samples are programmed, in which longitudinal rows samples are to
be dispensed, what reagents are to be added at a given station,
operate indicator lights on the program board 398 to indicate which
samples are in progress, which tests are to readout, and when the
readout function is to be performed. Thus the computer 400 will
repeat every machine cycle until it detects no further programming.
At this time the sweep board 464 will return to the zero position,
the master time 272 will stop running and the apparatus will be
placed under the control of the end wash timer 276 as discussed in
connection with FIG. 34.
However, in addition to the 60 rows of contacts 463, the stationary
board 462, because the apparatus 20 is a continuous cycling
apparatus and because the boards are physically constructed
linearly, the stationary board 462 will include an additional 20
rows of contacts 463 which are electrically jumpered to the first
20 rows of contacts on the stationary board 462 whereby the linear
board may function as a rotary switch, although of course a rotary
board may be used in place of boards 462 and 464, by picking up the
information programmed on the first 20 rows of buttons 463 as the
sweep board 464 passes the first contacts. During operation of the
first position on sweep board, 464 will index from zero position to
position 80 on the stationary board, then the sweep board reverse
416 will actuate to return the sweep board to position number 21 on
the stationary board and will continue to index between position 80
and position 21 until programming ceases. Then sweep board 464 will
return to zero position. The reagent selection board 113 is shown
in FIG. 64 wherein jump cables are provided to actuate the various
reagent solenoids 324 at the proper station on the belt. In
addition, the sweep board transmits information to the readout
timer for controlling the readout and recording functions. The
reagent selection board 113 includes rows 127 of receptacles
connected to the electrical solenoids 324, which for the tests
being programmed on the apparatus in FIG. 2, requires 16 reagents
and solenoids thereby requiring 16 receptacles in rows 127. In
addition, since there are provided 17 possible tube stations for
each test at which reagents may be dispensed, the reagent selection
board 113 includes 17 rows 129 of ten receptacles which are
connected to the re-agent dispensing pins on the sweep board 464.
Therefore, in order to set the apparatus up, various jump cables
125, all of which are not shown, are connected from the reagent
solenoid receptacles in rows 127 to the proper reagent station
receptacle in rows 129 so that when that particular station is
reached by the sweep board 464, the proper reagent solenoid will be
actuated to dispense that reagent into the proper reaction tube
24.
Referring again to FIG. 6, buttons 472, 474 and 402 are provided to
start and stop apparatus 20. Button 472 is an off button for
stopping the entire apparatus. Button 474 is a standby button which
is actuated prior to starting the operate button 402. The standby
button 474 when actuated actuates the magnetic contactor 448 which
provides power to circuits 1-15 and makes apparatus ready for
operation so that actuating the operate button 402 actuates the
master timer 272 which starts the automatic chemical analysis.
Referring now to FIG. 63, an electrical block schematic diagram is
shown of the functional controls of the present invention. As has
previously been indicated the desired tests which are to be
performed are programmed on the push button program board 398,
thereby providing a discretionary control on what chemical tests
are to be performed on each sample. Also, the samples have been
sorted on the sample table 32 in the sample containers 46 and the
standby button 474 (FIG. 6) is actuated to bring the various
heating baths up to their proper temperature. Actuation of the
operate button 402 (FIG. 6) actuates the master timer 272 which
transmits a signal to the programmed board 398 and the computer
which includes stationary board 462 and the movable sweep board
464.
From the sweep board 464 information is sent to the sample
selection control 115 for storage. Selection control 115 transmits
a signal to the carriage arm valve 70 and actuates the aspiration
timer 118 through the carriage control 116. In addition, the sample
selection control 115 transmits signals to the dispenser control
111, the dispenser timer 122, the aspiration timer 118 and the
carriage control 116. A signal is sent from the carriage control
116 to the carriage clutch 76 to actuate the carriage and motor 72
(FIG. 16) to move the pick up and dispensing needle 62 over the
pickup station on the sample table 32. As more fully described in
connection with FIG. 16 the needle 62 moves into the cup 46 and
aspirates the programmed amount of sample, the dispenser timer 123
reverses the dispenser clutch 114, the needle is raised, a segment
of sample is dispensed back into the sample cup 46, the carriage
arm 66 moves back over the row of reaction tubes 24 and the
dispensing timer 123 stops at each of the programmed longitudinal
rows 26 of tubes and dispenses a sample of serum.
In addition, the sweep board 464 transmits information to the
reagent selection board 113 to actuate the reagent solenoid valves
324 to provide a measured amount of the correct reagent at the
proper station in the cycle.
The sweep board 464, which rreceives the programmed information
from the stationary board 462, actuates the readout timer 374,
which controls the raising and lowering of the readout block 342,
for aspirating the fill and expel assembly 349 therein and
expelling it again after the conclusion of the readout tests. The
readout timer 374 also controls the recorder timer 410 which in
turn scans each of the programmed tests and records them on the
recorder 386.
During each cycle the master timer 272 signals the conveyor belt 22
which is indexed, provides the signals for the transmission of
programmed information to the function circuits and commencement of
the functions, signals the deprogramming of the control buttons
upon completion of each individually programmed sample, actuates
the advance control 414 to advance the sweep board to the
programmed signals for the next row of programmed tests, signals
the tube wash assembly 277 to wash the drained tubes, and in
addition, signals the sample table 32 which is indexed.
Of course, it is important that the belt 22, the sample rotary
indexing table 32, and the sweep board 464 be synchronized in
relative position at all times to insure that the correct sample on
the sample indexing table is picked up and dispensed in the
corresponding transverse row of tubes on the belt 22 and the
operating functions are synchronized.
Thus, referring to FIG. 67, a synchronization switch 479 may be
positioned to measure the indexed position of the belt 22 such as
being driven by a belt drive 481 connected to one of the belt 22
sprockets. Thus, as the belt is indexed one tube row, the
synchronization switch 479 is rotated to indicate the position of
the belt 22. Similarly, another synchronization switch 480 (a
double layer wafer switch) is positioned connected to the rotary
table 32 to measure the rotational position of the table. And the
synchronization switches 479 and 480 are connected in series
through the computer 400 comprising the sweep board 464 to insure
that the indexing table 32, the belt 22, and stationary board 462
and the sweep board 464 are in synchronization before proceeding
with the next sequence of tests.
The present invention therefore is well adapted to carry out the
objects and attain the ends and advantages mentioned as well as
others inherent therein. While a presently preferred embodiment of
the invention is given for the purpose of disclosure, numerous
changes in the details of construction, and arrangement of parts
will readily suggest themselves to those skilled in the art and
which are encompassed within the spirit of the invention and the
scope of the appended claims.
* * * * *